Wood Street Clinic Blog

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New heart failure therapy projected to increase life expectancy

Heart failure, the leading cause of hospitalization for Americans over the age of 65, accounts for more than one million hospitalizations in the US each year. Nearly six million Americans have heart failure, about half of whom have the reduced ejection fraction form, a reduced capability to pump blood from the heart. Heart failure patients with a reduced capability to pump blood from the heart have a marked increased risk for further cardiac events and death.

New research from Brigham and Women's Hospital finds that heart failure patients with reduced ejection fraction who are treated with sacubitril-valsartan have a projected increased life expectancy of one and a half to two years, as compared to those treated with enalapril, the current standard of care in heart failure. These findings are published in the December 3 issue of the New England Journal of Medicine.

"These results help both patients and their physicians understand the impact of switching from the standard of care to sacubitril-valsartan, in terms of a benefit that they can easily understand," said Scott D. Solomon, MD, senior author and director of Non-Invasive Cardiology at Brigham and Women's Hospital (BWH) and Professor of Medicine at Harvard Medical School. "Patients want to know how much longer they are going to live, rather than how much their risk will be reduced."

In this new analysis, researchers examined data from 8,399 patients in the PARADIGM-HF study, the largest clinical trial ever conducted in heart failure, and used actuarial methods that are typically used by the insurance industry, to measure the estimated lifetime benefits of treatment with sacubitril-valsartan as determined by age-specific cardiovascular events. Researchers derived expected survival times using data from the beginning of the study and the age at the time of a cardiovascular event. An average duration of event-free survival was estimated using long-term follow up data from the clinical trial.

Assuming that the protective effects of sacubitril-valsartan remain consistent with long-term use, researchers estimated that the benefits were similar across a wide range of ages. Specifically, patients 45-75 years old using sacubitril-valsartan had a projected extended benefit of one to two years of increased life expectancy, free from heart failure hospitalization, when compared to patients of the same age who were treated with enalapril.

The PARADIGM-HF trial was supported by Novartis. Novartis manufactures sacubitril-valsartan under the brand name, Entresto ™.

About PARADIGM-HF

The PARADIGM-HF trial previously showed that sacubitril-valsartan was superior to enalapril in reducing the rates of hospitalization for heart failure, death from cardiovascular causes, and death from any cause among heart failure patients with a reduced capability to pump blood from the heart (ejection fraction). Sacubitril-valsartan was shown in PARADIGM-HF to reduce cardiovascular death or heart failure hospitalization by 20 percent, and also improved overall survival by 16 percent, versus enalapril. The study was stopped early by the Data Monitoring Committee overseeing the study because of overwhelming benefit in patients treated with sacubitril-valsartan. The primary results of the PARADIGM-HF trial were published in The New England Journal of Medicine in 2014.

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Biophysicists develop a model for arterial thrombus formation

A group of biophysicists, including representatives from MIPT, has developed a mathematical model of arterial thrombus formation, which is the main cause of heart attacks and strokes. The scientists described the process of platelet aggregation as being similar to the popular video game Tetris and derived equations that allowed them to reproduce the wave process of platelet aggregate formation in a blood vessel.

Researchers from the Dmitry Rogachev Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology (FRCC PHOI), the Center for Theoretical Problems of Physico-Chemical Pharmacology, MIPT, Moscow State University, the Institute for Problems of Mechanical Engineering (St Petersburg), and the Free University of Berlin described the new model in the journal PLOS ONE. When discussing the development of the model and the members of the research team, Mikhail Panteleev, one of the authors of the publication, said: "Fazly Ataullakhanov and I formulated the problem and derived the equation, and Evgenia Babushkina (now a graduate student in Berlin), under the guidance of her mentor Nikolay Bessonov, developed solution methods for the two-dimensional case taking into account the changing hydrodynamics of the flow in which the thrombus is formed. She also performed all the simulations and analyses. Fazly and I are professors of the Department of Translational and Regenerative Medicine of MIPT's Faculty of Biological and Medical Physics, which is based at FRCC PHOI".

Develpoment of a continuous adsorption equation under assumption that thrombus formation occurs in the same way as the tiles become stacked up in the classic video game Tetris is a key aspect of the new model. In Tetris, the tiles either drop down onto a flat surface, or become attached to parts sticking out from the rest of the block. The only difference between thrombus formation and the game is that when a layer is complete, it does not disappear, therefore as time passes a thrombus is capable of obstructing the space it is in. In addition, the falling shapes are always the same: the model describes the aggregation of platelets, specialized blood cells.

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Coal burning emissions 'five times worse' for health

As the United Nations Conference on Climate Change kicks off in Paris, new research into the effects of coal burning pollution on heart health is timely.
[Coal burning power station]
A study finds that particles from burning coal are far worse for the health than other pollution sources.

The negative health consequences of pollution are well documented, but as additional evidence is collected, the overall picture becomes increasingly grim.

The present study shows, for the first time, the full impact of coal-based pollution on global heart health; the results are worrying.

Researchers at the NYU Langone Medical Center used data from 100 US cities to estimate the health impact of various types of airborne particulate matter.

The current study investigates not only the size of the particulate matter, but also the differing effects of particles from various sources.

The impact of air pollution

According to the World Health Organization (WHO), ambient air pollution was the cause of 3.7 million premature deaths in 2012.

Previous research has shown that smaller particulate matter, under 2.5 µm in diameter (PM2.5), is significantly worse for health than larger particles of 10 µm in diameter or more.

This difference is due to a smaller particle's ability to enter deeper into the lungs and successfully maneuver within the blood system. Containing substances such as arsenic, mercury and selenium, once inside the human body, they are free to wreak havoc.

Numerous studies have linked airborne particulate matter to a variety of health consequences, including:

Premature death in people with existing lung and cardiac disease Nonfatal heart attacks Aggravated asthma Irregular heartbeat Decreased lung function General respiratory problems.

A review in Circulation found that exposure to PM2.5 particles over just a few hours or weeks can trigger cardiovascular disease-related mortality and other negative health events. Longer exposure times - a year or more - increases the likelihood of cardiovascular mortality even further.

The current study is the first of its kind to split pollution by type, as well as size. Rather than simply looking at the diameter of particles, the researchers investigated the source of the pollution, for instance, coal burning, traffic fumes or wood burning.

Investigation lead Dr. George Thurston says:

"Past studies of this kind have essentially assumed that all PM2.5 particles have the same toxicity, irrespective of their source."

Thurston, professor of Population Health and Environmental Medicine at NYU Langone, delved into the records of 45,000 American patients between 1982 and 2004. He and his team estimated the size, type and amount of pollution each individual would have encountered.

The team used trace element "fingerprints" to estimate the contributions from each of the types of PM2.5. For instance:

Coal-burning: contains traces of selenium and arsenic Traffic emissions: contain elemental carbon Oil combustion: contains vanadium and nickel Soil particles: contain calcium and silicon Wood-burning particles: contain potassium.

Coal's worrying implications

The results are, to a certain extent, what one might expect - inhaling coal pollution is bad for the health. But the strength of the result certainly is rather surprising.

The research found that, pound-for-pound, particles from coal-burning were five times worse than other particle types of the same size.

Also, particles from burning fossil fuels were associated with an increased risk of death from ischemic heart disease.

Interestingly, the team found that PM2.5 from wind-blown soil and the burning of biomass, like wood, were "non-significant contributors" to mortality risk.

The study's authors recommend that, on the basis of these findings, the main thrust of air pollution control should focus specifically on coal burning.

On a similar note, Medical News Today recently covered research concluding that pollution increases health risks for diabetic women.

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Negative statin stories add to heart health risk

People are risking their health by acting on negative news stories about statins, according to a study published in The European Heart Journal, which shows that discontinuation of treatment is leading to an increase in heart attacks and early death.
[cholesterol]
Statins are a safe and useful drug for combatting cholesterol, say researchers.

Statins are considered some of the safest drugs. Prof. Børge Nordestgaard, co-author of the current study and chief physician at Copenhagen University Hospital in Denmark, describes statins as "a success story in modern medicine, and currently [...] the most effective way to prevent cardiovascular disease."

However, side effects can occur, particularly within the first 6 months, including muscle aches and, very rarely, rhabdomyolysis, when skeletal muscle is broken down. These side effects, or fear of them, can cause patients to discontinue their medication in the early stages.

Prof. Nordestgaard and his colleague Dr. Sune Nielsen, a senior scientist at Copenhagen University Hospital, wanted to know how negative news stories about statins affect patients' decisions about whether to continue their medication or not.

The study focused on 674,900 people aged 40 and older, across the entire Danish population, who were using statins between January 1995 and December 2010. The researchers tracked them until the end of 2011.

The team also identified 1,931 statin-related news stories from January 1995 onward in the Danish media and graded them as negative (110 stories), neutral (1,090 stories) and positive (731 stories).

In addition, they analyzed relationships between use of statins and having cardiovascular disease or diabetes when usage began, the passing of years, statin dose, being male, living in cities and being of non-Danish ethnicity.

From 1995-2010, the proportion of people using statins increased from less than 1% to 11%, while early statin discontinuation increased from 6% to 18%.

The number of all statin-related news stories (positive, neutral and negative) increased from 30 per year in 1995 to 400 in 2009, and for every negative nationwide news story about the cholesterol-lowering group of medicines, there was a 9% increased risk of people deciding to stop taking statins within 6 months of first being prescribed the drug.

The risk of abandoning the therapy early was also higher with every passing calendar year (4%), increased daily dose (4%), being male (5%), living in cities (13%) and for being of non-Danish ethnicity (67%).

In contrast, the risk of discontinuation fell after exposure to positive news stories (8%), having cardiovascular disease at the time the statins were first prescribed (27%) or having diabetes at that time (9%).

Prof. Nordestgaard says:

"We found that exposure to negative news stories about statins was linked to stopping statins early and explained 2% of all heart attacks and 1% of all deaths from cardiovascular disease associated with early discontinuation of statins. People who stop statins early have a 26% increased risk of a heart attack and an 18% increased risk of dying from cardiovascular disease when compared to people who continue to use them."

Although it is not certain that negative news stories cause people to stop taking statins, the findings suggest that this is likely; and the indication that early discontinuation leads to unnecessary heart attacks and deaths is of concern.

The authors stress the need to adhere to the drugs or face cardiovascular health problems, and they call for ways to encourage continuation.

Prof. Nordestgaard says ways must be developed to ensure that people stick to the therapy, especially in the first 6 months.

Positive news stories tend to be evidence-based, explaining how statins can prevent heart disease and early death. In contrast, negative news stories tend to focus on relatively rare and moderate side effects.

If there were no negative statin-related news stories, 1.3% of the population would continue to take their medications, the authors conclude.

Medical News Today recently reported that statins can reduce the effectiveness of the flu vaccine.

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New diaphragms grown from stem cells offer hope of a cure for common birth defect

An international collaboration between scientists in Sweden, Russia, and the United States has resulted in the successful engineering of new diaphragm tissue in rats using a mixture of stem cells and a 3D scaffold. When transplanted, it has regrown with the same complex mechanical properties of diaphragm muscle. The study is published in the journal Biomaterials, and offers hope of a cure for a common birth defect and possible future heart muscle repairs.

The multidisciplinary team behind the current study includes world-renowned researchers in the field of regenerative medicine and tissue engineering; Paolo Macchiarini, MD, PhD, Director of the Advanced Center for Regenerative Medicine and senior scientist at Karolinska Institutet; Doris Taylor, PhD, Regenerative Medicine Research Director at the Texas Heart Institute; and Mark Holterman, MD, PhD, Professor of Surgery and Pediatrics at the University of Illinois College of Medicine in Peoria, working in collaboration with a research team at the Kuban State Medical University in Russia.

The diaphragm is a sheet of muscle that has to contract and relax constantly to allow breathing. It is also important in swallowing, and acts as a barrier between the chest cavity and the abdomen. Malformations or holes in the diaphragm are found in 1 in 2,500 babies and can cause extreme, often fatal, symptoms.

At the moment, surgical repair of large defects like these involves using an artificial patch, which will not grow with the infant and does not provide any contraction to assist with breathing. The new technique presented in Biomaterials could instead allow such replacements to be grown especially for babies from their own cells, which would provide all the function of diaphragm tissue and would grow with them.

The success of this study also offers hope for the possibility of regenerating heart tissue, which undergoes similar pressure as it contracts and relaxes with every beat.

"So far, attempts to grow and transplant such new tissues have been conducted in the relatively simple organs of the bladder, windpipe and esophagus. The diaphragm, with its need for constant muscle contraction and relaxation puts complex demands on any 3D scaffold; until now, no one knew whether it would be possible to engineer," said Dr. Doris Taylor.

Dr. Paolo Macchiarini adds, "This bioengineered muscle tissue is a truly exciting step in our journey towards regenerating whole and complex organs. You can see the muscle contracting and doing its job as well as any naturally-grown tissue - there can be no argument that these replacements are truly regenerated, and the possibilities that this opens up for the future are enormous."

The field of tissue engineering involves 'growing' new tissues or organs from stem cells on three dimensional 'scaffolds,' which give both structural support and shape to the new tissue and guide the differentiation and proliferation of the stem cells. Engineered new tissues can not only help patients avoid the need for an organ donation, but also the need for the recipient to take immunosuppressant drugs.

In the current study, the researchers took diaphragm tissue from donor rats and removed all the living cells from it using a series of chemical treatments. This process removes anything that might cause an immune response in the recipient animals, while keeping all the connective tissue - or extracellular matrix - which gives tissues their structure and mechanical properties. When tested in vitro, these diaphragm scaffolds at first appeared to have lost their important rubber-like ability to be continually stretched and contracted for long periods of time. However, once seeded with bone marrow derived alloegenic stem cells and then transplanted into the animals, the diaphragm scaffolds began to function as well as undamaged organs.

The method must now be tested on larger animals before it can be tried in humans, but the hope is that tissue-engineered repairs for congenital diaphragm malformations will be at least as effective as current surgical options with the added benefit of growing with children throughout their lives.

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MRI reveals heart changes during apnea in elite divers

Athletes who engage in the extreme sport of free diving, descending hundreds of feet below the surface of the ocean while holding their breath, undergo significant cardiovascular changes, according to a new study presented at the annual meeting of the Radiological Society of North America (RSNA). These changes can pose potential dangers, particularly to inexperienced or cardiac untrained divers.

Apnea is the temporary suspension of breathing. The ancient practice of free or apnea diving has experienced immense growth worldwide over the past decade, due to coverage in the media and increased competition and training opportunities for elite and recreational divers. The sport can be dangerous, because divers must hold their breath for prolonged periods while undergoing massive water pressure and physiological changes.

Recreational divers are at greatest risk because of lack of conditioning, but even elite divers have suffered lasting or fatal effects resulting from free diving. Most recently, champion diver Natalia Molchanova was reported missing and presumed dead off the coast of Spain during a dive in August 2015.

Researchers at the University of Bonn in Bonn, Germany, used MRI to study the simulated effects of free diving on the cardiovascular systems of 17 elite free divers from Germany and Austria (age range 23 to 58). To study the effects of a lack of oxygen on heart function and blood flow, respectively, the divers underwent cardiac MRI and MRI of the carotid arteries before, during and after a maximum breath hold.

"We wanted to look at the changes that occur in the heart during apnea in real time," explained study author Jonas Dörner, M.D., who is now a radiology resident at the University Hospital of Cologne.

The average apnea was 299 seconds (just under five minutes) and 279 seconds or about four and a half minutes for the first and second MRI exams, respectively. The maximum breath hold (or apnea) during the exams was eight minutes and three seconds.

"These athletes train to be able to hold their breath for long periods," Dr. Dörner said. "When they get into the water, they are able to hold their breath even longer due to the diving reflex."

When submerged underwater without access to oxygen, the body responds with what is called "diving reflex," which includes a decreased heart rate, a constriction of blood vessels in the extremities, and a shift in blood flow from the extremities to the brain. These changes also occur - to a lesser degree - during prolonged breath holding without being submerged. As oxygenated blood is diverted from the rest of the body to the brain, blood pressure increases.

The MRI exams allowed the researchers to observe the cardiovascular changes involved in the diving reflex in real time. During apnea, the amount of blood flowing to the brain through the carotid arteries increased and then leveled off.

"At the beginning of the apnea period, the heart pumped more strongly than when the heart was at rest," Dr. Dörner said. "Over time, the heart dilated and began to struggle."

By the end of the apnea period, Dr. Dörner said the divers' heart function began to fail.

"At that point, not enough blood is being pumped to the brain," he said. "The heart is unable to pump against the high resistance of the blood vessels."

Although the changes in the divers' systolic heart function during apnea are similar to those in patients with systolic heart failure, Dr. Dörner said that the condition was transient in the divers.

"The divers' heart function recovered within minutes of breathing again," said Claas Nähle, M.D., head of this cardiac magnetic resonance research group. "It appears that elite divers develop compensatory mechanisms that help them adapt to the cardiovascular changes that occur during apnea."

However, for individuals with less training, free diving may be problematic.

"As a recreational activity, free diving could be harmful for someone who has heart or other medical conditions and is not well trained for the activity," said one of the study's leaders, Lars Eichhorn, M.D., from the Department of Anesthesiology and Intensive Care Medicine at the University Hospital of Bonn.

Dr. Eichhorn added that deaths among highly trained divers are mostly seen in the discipline called deep diving, a special type of apnea diving that combines the risk of prolonged apnea with changes of ambient pressure.

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Biophysicists develop a model for arterial thrombus formation

A group of biophysicists, including representatives from MIPT, have developed a mathematical model of arterial thrombus formation, which is the main cause of heart attacks and strokes. The scientists described the process of platelet aggregation as being similar to the popular video game Tetris and derived equations that allowed them to reproduce the wave process of platelet aggregate formation in a blood vessel.

Activated Thrombocyte
This is an activated thrombocyte on a slide with immobilized fibrinogen, one of the proteins found in the blood. Scanning electron microscopy.
Credit: Photograph courtesy of Sergey Obydenny / Wikimedia

Researchers from the Dmitry Rogachev Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology (FRCC PHOI), the Center for Theoretical Problems of Physico-Chemical Pharmacology, MIPT, Moscow State University, the Institute for Problems of Mechanical Engineering (St Petersburg), and the Free University of Berlin described the new model in the journal PLOS ONE. When discussing the development of the model and the members of the research team, Mikhail Panteleev, one of the authors of the publication, said:

"Fazly Ataullakhanov and I formulated the problem and established the equation, and Evgenia Babushkina, under the guidance of her teacher Nikolay Bessonov, developed solution methods in the two-dimensional case taking into account the hydrodynamics of the flow in which the thrombus is formed. She performed all the calculations herself; Fazly and I are professors of the Department of Translational and Regenerative Medicine of MIPT's Faculty of Biological and Medical Physics, which is based at FRCC PHOI (we work in a lot of different places...)".

Looking at thrombus formation in the same way as the tiles become stacked up in the classic video game Tetris is a key aspect of the new model. In Tetris, the tiles either drop down onto a flat surface, or become attached to parts sticking out from the rest of the block. The only difference between thrombus formation and the game is that when a layer is complete, it does not disappear, therefore as time passes a thrombus is capable of obstructing the space it is in. In addition, the falling shapes are always the same: the model describes the aggregation of thrombocytes, specialized blood cells.

Having described the mathematical process of how vacant areas on the surface of a growing thrombus are filled, the scientists were able to build first a one-dimensional model (as in Tetris), and then a two-dimensional model (thrombocytes are deposited in a dimensional plane). And at one point, the scientists began to consider certain thrombocytes as being dimensionless, and the thrombus itself as being continuous; in other words, the scientists went from a discrete model to a continuous model.

Discrete model: the system under study consists of individual particles, and the behaviour of each particle can be tracked individually. This makes it possible to simulate, for example, gas molecules in the problem of Brownian motion - representing each molecule as a particle colliding with a larger particle.

Continuous model: the system under study consists of solid objects that can freely change their size or any other characteristic. This can be used to model temperature increase in a functioning boiler for example - the output will be the temperature field in the volume under study.

The sequential solution of the equations obtained enabled the researchers to reproduce the dynamics of the growth of a real thrombus and study its behaviour under various conditions - in the case of damage to the vascular wall for example.

Active media and autowaves

In their paper, the researchers emphasize that the process of thrombus formation resembles a travelling wave, and this similarity is by no means accidental. They previously demonstrated that the thrombus formation process is like an autowave - the blood, which carries blood platelets and a number of special proteins for blood coagulation, is an active medium. At that time the conclusion drawn by the researchers was concerned with blood coagulation as a result of a cascade of biochemical reactions involving proteins, but it is also possible to talk of an active medium in the case of adhered platelets.

The term "active medium" plays a key role in non-linear dynamics - the science of mathematical modelling of a whole range of systems, from mixtures of interacting chemicals and lasers to forest fires and even social networks. The easiest way to describe an active medium is to use the example of a forest fire: every dry tree is not simply a passive object such as a molecule, but a potential source of thermal energy. If there is a fire near a dry tree, it too will start to burn and provide more heat, which can then ignite other trees. The ability of elements in the system to release energy is a key feature of an active medium.

In active media, a local event (lightning striking a tree for example) can initiate a transition process in a system from one state to another (in this case a dry tree becomes a burning tree). This process spreads like a wave in space and the specific physical nature of the system is not so important; the same equation can be used to describe entirely different cases. The term "autowave" means that wave propagation process is not passive, as in the case of seismic waves travelling from an earthquake's epicentre, but active - at each point the wave receives more energy. In the case of thrombus formation, instead of dry and burning trees, we need to think of platelets flowing in blood plasma. These platelets can go from a free-flowing state to a deposited state.

Thrombi: essential, but also dangerous

Thrombocytes (blood platelets) play an important role in forming thrombi, which block the blood vessels of clots. Under normal circumstances, they flow freely in the bloodstream, but if the vascular wall becomes damaged, they start to adhere to one another and to the vascular wall; in addition to this, the blood also contains many proteins required for thrombus formation. Even if there are no platelets, reactions with these proteins are able to help form a clot to block a damaged vessel and these reactions also occur in the form of autowaves. Normally, thrombi prevent blood loss in the human body when a blood vessel has become damaged. Sometimes, however, thrombus formation occurs not as a result of an injury with damage to a blood vessel, but as a result of a reaction to a pathological process, such as the build-up of fatty plaque within an artery in cases of atherosclerosis. This type of thrombus formation can block a vessel completely and cut off the blood supply to tissues and organs: this in turn can lead to myocardial infarction (blockage of the arteries to the heart), stroke (blockage of the arteries supplying blood to the brain), or gangrene of the extremities. The new model correctly describes arterial thrombus formation - these particular thrombi consist mainly of platelets; blood proteins play a relatively small role in the process.

Prospects

Mikhail Panteleev also told MIPT's press service about the prospects of studying thrombi and why the researchers chose to look at arteries, rather than venous thrombi or the blood clotting process in the capillaries: We are working on various issues in the field of hemostasis - the "physiological" process of wound clotting, as well as venous and arterial blood clots. Arterial blood clots in particular are very interesting. And also social importance (heart attacks and ischemic strokes), and complex mechanisms (blood proteins also play a key role here that is not fully understood). However, we have always had difficulty working with arterial blood clots in particular, in terms of developing and implementing computer models, because the subject involves a very difficult combination of mechanics (cell attachments), hydrodynamics with variable geometry, and biochemistry. There is no standard software program that can adequately address the problem.

In our paper in PLOS ONE, we tried to use the most primitive description of a thrombus as a continuous medium, rather than discrete particles. This approximation is rough in many respects and it limits the scope of the research, but it is able to give us some common patterns. On the one hand, we plan to continue to apply it to specific tasks, as far as is possible, and on the other hand, we are developing more sophisticated and advanced models with three-dimensional blood cells, the full mechanics of their interaction, and the proper biochemistry. This will be done only on supercomputers of course. Another aspect is the "inside" of a thrombocyte, modelling intracellular signalling, calcium oscillations, and the collapse of mitochondria in thrombocytes. This topic has been addressed in a number of papers that have already been published, including a very recent paper in Molecular BioSystems. Over time, I hope that all these projects will merge together into full multi-scale model of thrombus formation.

In order to understand the social importance of the problem described by Mikhail Panteleev, it should be noted that every day around 1000 people in Russia suffer a stroke and of those who survive, 2 in 3 are left with a disability. Contrary to popular belief, strokes not only affect the elderly, but also people under the age of 45 - in approximately 1 in 8 cases. Signs of a stroke include partial paralysis and a sudden onset of weakness. In a number of cases, the symptoms, which include slurred speech and a staggering gait, may make it appear as if the sufferer is under the influence of alcohol: this error of judgement could cost the lives of victims of an acute cerebrovascular accident.

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First outcomes report from novel heart surgery registry shows excellent results for TAVR

Four years after its approval in the United States, transcatheter aortic valve replacement (TAVR) continues to evolve and demonstrate positive outcomes for patients with aortic stenosis, a common heart problem, according to a report published online by The Annals of Thoracic Surgery and the Journal of the American College of Cardiology.

Shortly after the Food and Drug Administration (FDA) approved the first heart valve for TAVR, the US Centers for Medicare & Medicaid Services (CMS) required all hospitals performing TAVR to capture clinical information in The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry (STS/ACC TVT Registry™) as a requirement for Medicare coverage. With collaboration from the FDA, CMS, the National Institutes of Health, and Duke Clinical Research Institute, the development and deployment of the STS/ACC TVT Registry represented the first time that such a diverse group came together to support the safe introduction and rational dispersion of a new medical device in the US.

In the report, David R. Holmes Jr., MD, from Mayo Clinic in Rochester, Minn., Frederick L. Grover, MD, from University of Colorado in Denver, and colleagues provided an overview of trends and analyzed outcomes of patients having TAVR procedures. The report also described the future of the TVT Registry.

"The most important takeaway is the fact that the TAVR procedure continues to change since its initial approval by the FDA in 2011," said Dr. Holmes. "Patients undergoing TAVR remain primarily elderly and high-risk for surgical replacement, but the predicted risk of mortality has declined over the course of time. This is the result of changes in regulatory instructions for use and approval of alternative access points."

The report included information on 26,414 TAVR procedures performed from January 1, 2012, through December 31, 2014, and recorded in the TVT Registry. The researchers compared outcomes in patients who underwent TAVR in 2012-2013 with the outcomes of patients who underwent the procedure in 2014. When TAVR was first approved, it required cardiothoracic surgeons and cardiologists to use transfemoral access (via the groin), but later expanded to include transapical (via the heart muscle), transaortic (via the aorta), and transcarotid (via the right common carotid artery) access.

The researchers found that TAVR patients in 2012-2013 and 2014 were elderly (average age 82 years), had multiple health conditions, were often frail, and had poor self-reported health status.

Results following the procedures also showed that risk for mortality, myocardial infarction (heart attack), kidney injury, and neurologic complications were low and appeared to be clinically consistent in both groups. The most common complications were vascular and bleeding requiring transfusion, but vascular complications decreased between 2012-2013 and 2014 (5.6% vs. 4.2%) and site-reported stroke rates remained stable at 2.2%.

"For patients, particularly those who are frail or elderly and have multiple health conditions, the outcomes reported thus far should provide reassurance that TAVR is safe and effective for the relief of symptoms in the short term," said Dr. Grover. "This patient population is more often concerned with quality of life than long-term results, and our report shows that TAVR is a good option for them."

In addition, the researchers found that more heart teams are now using moderate sedation instead of general anesthesia, which allows for quicker recovery after surgery and shorter procedure durations. It also has the potential to reduce the patient's length of stay in the hospital, which can reduce overall hospital costs.

Importance for Patients

As less invasive procedures become more available to patients, the TVT Registry will continue to play an important role in tracking both short- and long-term outcomes, as well as providing surveillance of medical devices once they are approved by the FDA.

"This Registry presents an incredible opportunity for physicians and their heart teams to be part of a novel post-market surveillance process, enabling STS and ACC to work very closely with regulatory agencies and industry," said Dr. Grover. "We believe that our work will help the FDA to approve important life-saving devices earlier, knowing that our Registry will be used to carefully monitor patients following device implantation."

Device Tracking Ability

In addition to tracking patient outcomes, this first report from the TVT Registry also allowed researchers to track trends in device utilization over the course of the study period. "For example, one important finding we noticed in this report was that TAVR is currently underutilized in black patients (less than 5% of TAVR patients were black)," said Dr. Holmes. "Information like this would have been unknown to us before, but because the Registry data were published, we know about the issue and can more easily address it in clinical practice."

Future of the Registry

In an accompanying editorial, Michael J. Reardon, MD and Neal S. Kleiman, MD, from Houston Methodist DeBakey Heart & Vascular Center in Houston, discussed the impact that the TVT Registry has had to date and where they see it heading in the future. "The STS/ACC TVT Registry represents an unprecedented collaboration between the national cardiology and cardiothoracic surgery societies," said Dr. Reardon. "This multidisciplinary approach has shown tremendous benefit in other areas, such as oncology. I firmly believe that this 'team' approach will allow patients to benefit greatly from the best of both specialties."

He added that as TAVR enters the mainstream of clinical practice, the Registry will need to embrace new challenges and provide new opportunities, "Namely, the Registry will become more useful in showing the relationships between surgeon experience, institutional volume, and the likelihood of achieving favorable patient outcomes."

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Registry review shows positive results for novel heart surgery procedure

A new report published in the Annals of Thoracic Surgery and the Journal of the American College of Cardiology reveals how, 4 years after its approval in the US, a minimally invasive form of heart surgery has helped improve outcomes for patients with one of the most common and severe heart valve conditions.
[An older lady in hospital]
Researchers say their review should reassure elderly patients with aortic stenosis that they will benefit from TAVR.

Transcatheter aortic valve replacement (TAVR) was approved by the US Food and Drug Administration (FDA) in November 2011 for the treatment of aortic stenosis - a condition in which the aortic valve opening narrows, restricting blood flow from the heart to the rest of the body.

Aortic stenosis can be life-threatening; the heart has to work harder in an attempt to pump enough blood through the narrowed valve, causing it to weaken, which can lead to chest pain, arrhythmia, heart failure and cardiac arrest.

Open-heart surgery involving aortic valve replacement remains the primary treatment for aortic stenosis, but TAVR offers a less invasive option for individuals who are too high risk to receive the standard procedure.

TAVR involves replacing the aortic valve with a prosthetic one. When the procedure was first approved, it could only be completed by insertion of a catheter through the femoral artery in the groin (transfemoral). It has since expanded so the procedure can be done via the left ventriclular apex of the heart (transcapial), the aorta (transaortic) or the right common carotid artery (transcarotid).

Soon after TAVR was given the green light, the US Centers for Medicare & Medicaid Services (CMS) required that all hospitals performing the procedure report clinical outcomes via The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry (STS/ACC TVT Registry) - a requirement for Medicare coverage.

The STS/ACC TVT Registry was set up by the FDA, CMS, the National Institutes of Health and Duke Clinical Research Institute.

Now, Dr. David R. Holmes, from Mayo Clinic in Rochester, MN, and colleagues have reviewed this data for the first time, providing an overview of the evolution of TAVR since its approval and the clinical outcomes from the procedure.

Findings 'should reassure patients TAVR is safe and effective'

The Registry included 26,414 patients who underwent TAVR between January 1, 2012, and December 31, 2014.

Dr. Holmes and colleagues compared the outcomes of patients who underwent the procedure in 2012-13 with those who had the procedure in 2014, enabling them to determine whether clinical outcomes have changed over time alongside procedural changes.

The team found that the average age of patients who underwent TAVR in 2012-13 and 2014 was 82, and most were frail, had poor self-reported health status and multiple health conditions.

On assessing clinical outcomes, the researchers found that the risks for neurological complications, heart attack, kidney injury and mortality were similarly low for both groups.

Vascular problems and bleeding requiring transfusion were the most common complications from TAVR, though the researchers note the rate of vascular complications fell between 2012-13 and 2014, from 5.6% to 4.2%. In addition, site-reported stroke rates stayed the same, at 2.2%.

Additionally, the team found that the use of moderate sedation rather than general anesthesia is on the rise, which may speed up the procedure and patients' recovery and, in turn, reduce the length of hospital stays.

Report coauthor Dr. Frederick L. Grover, from the University of Colorado, believes these results should give elderly patients with aortic stenosis the confidence that the TAVR procedure will help them:

"For patients, particularly those who are frail or elderly and have multiple health conditions, the outcomes reported thus far should provide reassurance that TAVR is safe and effective for the relief of symptoms in the short term.

This patient population is more often concerned with quality of life than long-term results, and our report shows that TAVR is a good option for them."

Patients will continue to benefit from Registry data

The Registry data also enabled the researchers to identify some shortfalls when it comes to the use of TAVR. For example, they found the procedure is underutilized among certain race/ethnic groups, with only 5% of black aortic stenosis patients undergoing TAVR.

"Information like this would have been unknown to us before, but because the Registry data were published, we know about the issue and can more easily address it in clinical practice," notes Dr. Holmes.

In an editorial linked to the study, Drs. Michael J. Reardon and Neal S. Kleiman, from Houston Methodist DeBakey Heart & Vascular Center in Texas, note the importance of the STS/ACC TVT Registry for providing ongoing data on the use and clinical outcomes of TAVR.

"This multidisciplinary approach has shown tremendous benefit in other areas, such as oncology," says Dr. Reardon. "I firmly believe that this 'team' approach will allow patients to benefit greatly from the best of both specialties." 

Last year, Medical News Today reported on a study published in the Journal of Thoracic and Cardiovascular Surgery, in which researchers detailed the first completely endoscopic aortic valve replacement conducted on two patients in France.

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Poor fitness in early adulthood linked to future death, cardiovascular risks

Though the headline may sound like an obvious conclusion - we all know better physical fitness leads to better health outcomes - a new study published in JAMA Internal Medicine examines the role of cardiorespiratory fitness and its changes in young adulthood on long-term cardiovascular outcomes; previous research has only investigated this link in older adults.
Woman running at a gym
Better fitness in early adulthood is linked to long-term cardiovascular benefits, according to the latest study.

"Most large studies of CRF [cardiorespiratory fitness] focus on middle-aged and older adults, demonstrating that fitness at a single point in time is associated with risk," write the authors, who are led by Dr. Joao A.C. Lima, of Johns Hopkins Medical School in Baltimore, MD.

As such, Dr. Lima and colleagues wanted to investigate baseline CRF and changes in young adults in relation to future cardiovascular disease (CVD).

They did this by assessing participants from the Coronary Artery Risk Development in Young Adults (CARDIA) study, which included 4,872 adults in the US aged 18-30 years.

Every 43 seconds in the US, someone has a heart attack, and every minute, someone dies from a heart disease-related event. Because heart disease is the leading cause of death for both men and women in the US, mitigating cardiovascular risks is a major public health priority.

Fitness reductions linked to 21% increased risk of death

As part of the study, participants underwent treadmill exercise testing at baseline, which was from March 1985-June 1986. Then, 7 years later, a further 2,472 participants had a second treadmill test.

The median follow-up time was 27 years, at which point, the participants were assessed for obesity, left ventricular heart mass and strain - which is a measure of heart muscle contraction strength - coronary artery calcification (CAC) and CVD.

Of the 4,872 participants, 5.6% died during follow-up, and 4% experienced CVD events. Of the 273 deaths, 200 were not cardiovascular related, and 22.5% of the deaths were related to cancer.

Additionally, out of 3,067 of the participants, 28.3% had any CAC by year 25, and out of 3,001 participants, 10.8% had a thickening of the heart muscle.

The treadmill tests in the study involved as many as nine 2-minute tests of gradually increasing difficulty, and the researchers say their results show that each additional minute of baseline treadmill test duration was linked with a 15% lower risk of death and a 12% lower CVD risk.

Furthermore, each 1-minute increase was linked with reduced left ventricular mass and better strain.

When the researchers conducted a second treadmill assessment at 7 years, they found that a 1-minute reduction in fitness by year 7 was linked with a 21% increased risk of death and a 20% increased risk of CVD.

The team also found that each 1-minute reduction was linked with worsening strain. However, test duration or change in fitness was not associated with CAC.

Commenting on this finding, the researchers write:

"The finding that fitness is related to development of subclinical changes in myocardial structure and function, but not CAC, sheds light on potential mechanistic benefits of exercise in youth not captured by CAC."

They add that they "were surprised to find that fitness (or its change over time) was not associated with the extent or the presence of CAC in long-term follow-up."

Reducing obesity 'not the only benefit of early adulthood fitness'

As a result of their findings, the researchers say that efforts to improve early adulthood fitness "may affect long-term health at the earliest stages in CVD pathogenesis."

In a linked commentary, Drs. David E. Chiriboga and Ira S. Ockene, of the University of Massachusetts Medical School in Worcester, write:


"The present report draws attention to the substantive and independent value of physical activity and CRF in CVD prevention regardless of age, race or sex, highlighting its significance as a tool for individuals and population-based intervention.


Policies directed at promotion of physical activity in the population will have a significant effect on CVD morbidity and mortality."

The study authors note that their findings could not be explained entirely by body mass index (BMI), weight changes or cardiometabolic disease, which suggests that reducing obesity - and its ill effects - "may not be the only mechanism of benefit of being fit early in adulthood."

Medical News Today recently reported on a study that suggested there are some cases where vigorous exercise can actually be bad for the heart.

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Overweight, obesity in early adulthood raises risk for sudden cardiac death

Another study has added to the overwhelming evidence of the negative health outcomes caused by excess weight, finding that overweight and obesity in early adulthood raises the risk for sudden cardiac death later in life. What is more, this risk may not be offset by later weight loss.
Image of an obese woman with a heart problem.
Being overweight or obese in early to mid-adulthood may increase sudden cardiac death risk.

Lead author Stephanie Chiuve, assistant professor of medicine at Harvard Medical School in Boston, MA, says the findings - published in the journal JACC: Clinical Electrophysiology - highlight the importance of maintaining a healthy weight throughout adulthood.

Overweight and obesity are a growing health concern in the US, affecting almost 70% of adults and putting them at greater risk for stroke, heart disease, diabetes and some forms of cancer.

In this latest study, Chiuve and colleagues set out to gain a better understanding about how overweight and obesity throughout adulthood impact the risk for sudden cardiac death - unexpected death due to loss of heart function - non-fatal heart attack and fatal coronary heart disease (CHD).

To do so, the team analyzed data of 72,484 women who were part of the Nurses' Health Study, following them between 1980-2012.

Information about participants' weight and height at study baseline and at the age of 18 was collected and used to calculate their body mass index (BMI). Such information was also collected through questionnaires completed every 2 years throughout the duration of the study.

Over the 32-year study period, there were 2,272 cases of non-fatal heart attack, 1,286 cases of fatal CHD and 445 cases of sudden cardiac death.

The researchers found that women who were overweight - defined as a BMI of 25-30 - were 1.5 times more likely to experience sudden cardiac death in the subsequent 2 years than those with a healthy weight (BMI of 21-23), while women who were obese were at twice the risk for sudden cardiac death.

Women who were overweight or obese at study baseline or who were obese at the age of 18 had an increased risk of sudden cardiac death throughout the entire 32-year study, according to the results, and this risk was not completely overturned by later weight loss.

The team also found that the risk of sudden cardiac death was higher for women who gained weight in early to mid-adulthood; those who gained at least 44 pounds during this period were at twice the risk of sudden cardiac death, regardless of their BMI at the age of 18.

The researchers also uncovered a weaker association between higher BMI and greater risk for fatal CHD and non-fatal heart attack.

Commenting on their findings, Chiuve says:

"We found that it is important to maintain a healthy weight throughout adulthood as a way to minimize the risk of sudden cardiac death.

Nearly three quarters of all sudden cardiac deaths occur in patients not considered to be high-risk based on current guidelines. We must seek broader prevention strategies to reduce the burden of sudden cardiac death in the general population."

The team admits there are some limitations to their findings. For example, because the study participants were primarily white women, they may not apply to other ethnic groups. "Further research is needed to determine whether overweight and obesity are risk factors in multiethnic populations," they note.

Medical News Today recently reported on a study that claimed to shed light on why people who are overweight find weight loss more challenging.

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Exercise is not always the best thing for your heart

Exercise and its benefits on heart health are, of course, well documented. But there are some cases where vigorous exercise can actually be deadly.
[ECG machine]
New research investigates instances where extreme activity can be detrimental to the heart.

Normally, maintaining fitness through exercise helps keep a multitude of diseases at bay.

The proven benefits of exercise include a reduction in the risk of developing type 2 diabetes, hypertension, osteoporosis and colon cancer.

Added to that list are more obvious benefits: reduction in weight, lowered blood pressure and a drop in low-density lipoprotein (LDL), or "bad," cholesterol.

The effect of a single exercise program on any one of the above risk factors might be small, but when the effect is taken as a whole and combined with good nutrition, the positive implications on general health are vast.

However, Dr. Jeffrey Towbin and his team at the Cincinnati Children's Hospital Medical Center have recently been investigating situations when endurance exercise can have severe consequences.

The study, published in the American Journal of Physiology - Heart and Circulatory Physiology, investigated the effects of endurance exercise on arrhythmogenic ventricular cardiomyopathy.

Arrhythmogenic ventricular cardiomyopathy

Arrhythmogenic ventricular cardiomyopathy (AVC) is a rare disorder, but also the most common condition to cause sudden cardiac death during a bout of intense exercise. Most worryingly, it can be asymptomatic until the point of a major cardiac collapse.

AVC is a genetic disorder that affects the structural integrity of the heart wall.

Cells within the heart wall are linked together by proteins called desmosomes. When under duress - during intense exercise, for instance - the heart wall can become overstretched. The desmosome links are responsible for keeping the structure of the heart wall intact.

Desmosomes consist of various protein building blocks. In AVC, there are defects in one or more of these desmosome proteins. The faulty components prevent desmosomes from successfully holding the heart wall together.

In an AVC patient, during exercise, the heart cell links give way allowing gaps to form between cells. Scar tissue, in turn, forms between the cells. This scar tissue further weakens the heart's ability to hold up under fire.

The role of desmoplakin

One of the vital constituents of desmosomes is the protein, desmoplakin. Previous studies using mice with mutated forms of desmoplakin have shown the mice develop similar symptoms to human AVC.

In the present study, Dr. Towbin's team investigated the effect of vigorous exercise on these particular mice. The team found that endurance exercise brought on a significantly earlier onset of AVC symptoms.

Interestingly, the team managed to measure the desmosomes faults quite early on via biological markers. They noticed early signs of AVC before any cardiac symptoms presented. This is important because AVC is notoriously difficult to diagnose in its early phase; this particular finding could, therefore, be clinically useful in the future.

The changes in the heart wall in AVC are often patchy to begin with, making it difficult to detect via ECG. AVC patients' ECG readouts do not necessarily show any changes in the early phase, or they produce readings that could signal a number of different conditions.

Early outward symptoms of AVC are equally difficult to place - for instance, palpitations or light-headedness are early signs of AVC but could also be the fault of any number of disorders.

A biological marker that could act as an early warning could save lives.

A potential role for Wnt-beta-catenin

Dr Towbin's investigations threw out another intriguing finding. During exercise, the team noticed significant changes in the Wnt-beta-catenin pathway.

The Wnt-beta-catenin pathway is involved in promoting the growth of new cells and preventing the deposition of fat. This offers a potential mechanism of the increase in AVC's development seen during intense exercise.

Although the Wnt-beta-catenin pathway finding is only tentative, it gives researchers a new angle from which to approach research into AVC.

It seems AVC may be slowly letting down its guard. Future research now looks set to discover the mechanisms at play and potentially design new tests for its early detection.

Medical News Today recently discussed the potential of a pill that offers the same benefits as exercise.

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Fewer heart attacks with mind-body medicine

Mind-body medicine (MBM) is a holistic approach that has the potential to ward off more heart attacks than conventional prevention programs. That is the conclusion reached by Holger Cramer and colleagues in a systematic review and meta-analysis presented in the latest issue of Deutsches Ärzteblatt International. They show that MBM in cardiac patients has a positive effect on coronary events, atherosclerosis, and high blood pressure.

Three of the most important risk factors for coronary heart disease - lack of exercise, overweight, and stress - are amenable to intervention. While conventional preventive measures concentrate on exercise and advice on nutrition, MBM also embraces relaxation methods and psychological motivation techniques. In the studies analyzed by Cramer et al., coronary events occurred in 68 of 307 patients who received conventional interventions but in only half as many - 33/308 - of those on MBM prevention programs. The authors point out that despite this positive effect MBM does not decrease mortality in cardiac patients. Nevertheless, the lower incidence of coronary events is beneficial. They therefore endorse MBM or other comparable programs for lifestyle modification.

Article: Mind-body medicine in the secondary prevention of coronary heart disease - a systematic review and meta-analysis, Cramer H, Lauche R, Paul A, Langhorst J, Michalsen A, Dobos G., Dtsch Arztebl Int, doi: 10.3238/arztebl.2015.0759, published 6 November 2015.

For any corrections of factual information, or to contact our editorial team, please see our contact page.

Please note: Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional. For more information, please read our terms of use.

Copyright Medical News Today: Excluding email/sharing services explicitly offered on this website, material published on Medical News Today may not be reproduced, or distributed without the prior written permission of Medilexicon International Ltd. Please contact us for further details.

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Ultrasound examinations can identify patients at risk of stroke

Ultrasound, a non-invasive technique commonly used to study the presence of atherosclerosis disease in blood vessels, can be used to identify patients at increased risk of future stroke who could benefit from surgery. Since surgical treatment to prevent stroke is only considered beneficial to some, ultrasound can prove useful in preventing unnecessary surgical intervention, new research at Umeå University in Sweden shows.

Atherosclerosis, or hardening of the arteries, is an inflammatory disease affecting the arteries supplying the brain, heart, other organs and extremities with oxygen-rich blood. A well-established atherosclerosis disease, with accumulation of plaque narrowing the arteries, can obstruct the blood supply to the brain and other vital organs. Atherosclerosis in the neck arteries can cause stroke. The serious condition, known as carotid stenosis, is quite common in the elderly as well as in people with risk factors such as hypertension, smoking, diabetes, hypercholesterolemia and obesity.

Atherosclerosis disease progression can be controlled by medical treatment including cholesterol-lowering drugs, and significant narrowing in symptomatic patients can be treated surgically.

"We know that preventive surgical treatment of carotid stenosis is only beneficial for a small subgroup, and that most asymptomatic patients will do better with only medical therapy. By using ultrasound, we can identify the patients who are at a higher risk of stroke and thus would benefit from surgery. But preventing unnecessary surgical intervention in most cases is equally important," says Fisnik Jashari, doctoral student at the Department of Public Health and Clinical Medicine and author of the dissertation.

To assess the nature of atherosclerosis disease and the extent of plaque build-up, the non-invasive ultrasound method remains favoured over most others because it is radiation free, cheap and patient-friendly.

Fisnik Jashari comes from Prishtina in Kosovo, where he works as resident doctor in Neurology. He is a doctoral student in the Department of Public Health and Clinical Medicine at Umeå University.

For any corrections of factual information, or to contact our editorial team, please see our contact page.

Please note: Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional. For more information, please read our terms of use.

Copyright Medical News Today: Excluding email/sharing services explicitly offered on this website, material published on Medical News Today may not be reproduced, or distributed without the prior written permission of Medilexicon International Ltd. Please contact us for further details.

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A different kind of anesthesia - a possible treatment for stress induced cardiomyopathy

Stress induced cardiomyopathy after cerebral hemorrhage has been shown to increase the risk of further brain damage. These patients can now be identified by a simple blood test, and a possible treatment for stress induced cardiomyopathy has been discovered - a different kind of anesthesia than that currently being used. A new doctoral thesis at Sahlgrenska Academy has explored these issues.

Stress induced cardiomyopathy is a relatively recently discovered disease where part of the heart muscle ceases to function and results in the heart having reduced pumping capacity. Approximately 90 percent of those affected are upper middle-aged women. The onset is similar to a heart attack, with chest pain and difficulty breathing, but stress induced cardiomyopathy follows a different course.

With stress induced heart failure, the heart spontaneously recovers within a few weeks and thus the prognosis has been seen as good; but, new findings show the prognosis to be approximately the same as for acute ischemic heart disease.

Followed for two years

In a new thesis from Sahlgrenska Academy, all patients from the region that suffered a specific type of cerebral hemorrhage (subarachnoid hemorrhage) were followed for two years. In conjunction with the hemorrhage, patients experience a strong stress component. Stress induced cardiomyopathy is therefore relatively common (10-20 percent of the patients) following this type of cerebral hemorrhage, which can cause significant brain damage.

"We saw that patients with stress induced cardiomyopathy had an increased risk of further brain damage in the aftermath of a cerebral hemorrhage and had a worse long-term prognosis, even after we made adjustments for other risk factors," says Jonatan Oras, PhD Student at Sahlgrenska Academy.

Biomarkers were identified

In the thesis, two biomarkers were identified that can be used to identify patients who suffer from stress induced heart failure.

"With a blood test, we are now able to quickly identify patients with stress induced heart failure and apply the right measures sooner," says Jonatan Oras.

A possible treatment

In the experimental part of the thesis, an animal model was used with rats to find a possible treatment for stress induced heart failure. It was found that if the animals were anesthetized with a particular anesthetic ( isoflurane), they did not develop heart failure and the heart muscle retained its elasticity and pumping capacity.

"When we used other anesthetics, including those currently in use in healthcare, we saw no cardioprotective effect. This is the first potential cardioprotective treatment for stress induced cardiomyopathy to be presented," says Jonatan Oras.

Further studies of this possible treatment for stress induced cardiomyopathy on patients at risk of developing stress induced cardiomyopathy should be conducted," Jonatan Oras points out.

Facts: Subarachnoid hemorrhage is a type of brain hemorrhage that is caused by a malformation of one of the brain's blood vessels bursting. It affects younger persons and can result in significant brain damage. Approximately 40 percent of patients die from the hemorrhage and a third of those that do survive sustain incapacitating brain damage that renders them unable to manage their daily lives. In connection with subarachnoid hemorrhage, the patients often experience a strong stress component and therefore, many of these patients suffer from stress induced cardiomyopathy in the aftermath.

The thesis Stress-induced cardiomyopathy - clinical and experimental studies was defended on November 13.

Link to thesis: http://hdl.handle.net/2077/39562.

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Pollution increases health risks for diabetic women

Airborne particulates have long been known to cause ill effects. A recent study links exposure to air pollution with an increased risk of cardiovascular disease and stroke in women with diabetes.
[Pollution from factory]
Air pollution has a significant impact on global health.

According to the World Health Organization (WHO), particulate matter (PM) air pollution contributes to approximately 7 million premature deaths each year.

That astonishing figure equates to 1 in 8 deaths globally.

Air pollution is now considered the world's number one environmental health risk. Consequently, a reduction in air pollution could save millions of lives.

As such, PM air pollution and its impact on public health is an area of intense interest and scientific investigation.

A US-wide study, published in the Journal of the American Heart Association, is the first to find links between particulate exposure and negative health effects in women with diabetes.

Health risks associated with particulate matter

Among other negative health impacts, particle pollution has been linked to premature death in people with heart or lung disease, nonfatal heart attacks, arrhythmia, decreased lung function and exacerbated asthma.

PM is also thought to contribute to cardiovascular disease (CVD) by an increase in inflammation, activation of coagulation and direct entry into systemic circulation.

The current study utilized data from the Nurses' Health Study, consisting of 114,537 women. Data was collected between 1989-2006.

The participants were predominantly white women of middle- and upper-socioeconomic status throughout the US.

From each participant's home address, the research team used a model to predict what type of air pollution they were likely to have been exposed to.

Next, the team collated incidences of CVD, coronary heart disease and strokes across the cohort. They calculated the impact of three different size groups of PM:

PM 2.5: fine particulate pollutants, smaller than 2.5 thousandths of a mm, i.e., smaller than dust PM 2.5-10: particulate pollutants from 2.5-10 thousandths of a mm, for instance windblown and road dust, and dust from crushing and grinding PM 10: includes all sizes of particles from both the PM 2.5 and PM 2.5-10 groups.

Risks for diabetic women

According to the data, all levels of PM gave a small elevated risk of CVD; women over the age of 70, who are obese or who live in the northeast or south of America were particularly at risk.

The team also found that this risk of CVD and stroke was particularly high in women with diabetes. The risk increased with every 10 mg/m3 of air:

PM 2.5: 44% for CVD / 66% for stroke PM 2.5-10: 17% for CVD / 18% for stroke PM 10: 19% for CVD / 23% for stroke.

In regards to the increased risk associated with smaller particulate matter, lead study author Jaime E. Hart, assistant professor at Brigham and Women's Hospital and Harvard Medical School in Boston, MA, told Medical News Today:

"Many studies have shown that the smallest size fraction (PM 2.5) is associated with the highest risks. There is evidence that the smaller particles get deeper into the lungs and can even cross into the blood stream."

Their analysis adjusted for family history and smoking status, neither of which impacted the results. Those who had been subjected to smaller PM still had a significantly increased risk of CVD and stroke.

Because air pollution and diabetes are such hot topics, no doubt this will be the first of many investigations into the links between the two. The main thrust of the study was to highlight those groups within the population that might be at risk, and to raise awareness of the impact of PM air pollution.

Diabetics are an ever-growing section of the American population, and any implications of air quality on their general health need to be investigated.

Hart says:

"It is important to identify these subgroups, so that pollution standards can be developed that protect them."

MNT recently wrote about pollution and its role as a risk factor for anxiety and trigger for stroke.

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Prolonged sitting worsens health for heart disease patients

There is increasing evidence that sitting for long periods is bad for health, regardless of whether a person exercises. Now, a new study finds sedentary behavior may worsen the health of individuals who already have heart disease, even if they are active.
[An overweight man sitting on a sofa]
Researchers found prolonged sitting was linked to higher BMI and lower cardiorespiratory fitness in patients with heart disease.

The research - led by Dr. Stephanie Prince of the University of Ottawa Heart Institute in Canada - was recently published in the European Journal of Cardiovascular Prevention.

Studies show that we spend around 7.7 hours a day sitting down, which can have severe consequences for health, including increased risk of type 2 diabetes, obesity and heart disease. Recent studies have shown sedentary behavior may even increase the risk of anxiety and non-alcoholic fatty liver disease.

What is more, some studies have suggested that regular exercise may not counteract the negative health effects associated with sedentary behavior.

But what about individuals who already have certain health conditions? Does prolonged sitting worsen their health? And if so, does exercise offset such effects? This is what Dr. Prince and colleagues wanted to find out.

For their study, the team enrolled 278 patients with coronary heart disease (CHD) - the most common form of heart disease and a leading cause of death for men and women in the US.

All participants had completed a cardiac rehabilitation program, which showed them how to increase physical activity levels.

Fast facts about CHD

CHD is caused by a build-up of plaque in the coronary arteries, which prevents oxygen-rich blood from reaching the heart muscle CHD kills around 370,000 Americans every year High blood pressure, high cholesterol, overweight and obesity and diabetes are key risk factors for CHD.

Learn more about CHD

For 9 days, participants wore an activity monitor during waking hours, allowing the researchers to assess how long each subject spent sitting down and how long they spent engaging in light, moderate or vigorous exercise.

Additionally, the researchers assessed participants' body mass index (BMI) and cardiorespiratory fitness - the ability to engage in moderate- or high-intensity exercise for long periods - among other markers of health.

The team found that the participants were sedentary for an average of 8 hours daily, which they say was surprising given that they completed a program showing them how to get more exercise. "We assumed they would be less sedentary but they spent the majority of their day sitting," notes Dr. Prince.

On average, men spent 1 hour more sitting each day than women, which the researchers say is because women engaged in more light activity, such as housework and running errands.

Importantly, the researchers found that subjects who spent more time sitting had higher BMI and lower cardiorespiratory fitness - determined by maximal oxygen consumption, or VO2 peak.

What is more, these findings remained regardless of participants' age, gender or how much time they spent exercising. "In other words, people who sat for longer periods were heavier and less fit regardless of how much they exercised," says Dr. Prince.

The team says their findings emphasize the importance of reducing the amount of time we spend sitting down. Dr. Prince says:

"Limiting the amount of time we spend sitting may be as important as the amount we exercise. Sitting, watching TV, working at a computer and driving in a car are all sedentary behaviors and we need to take breaks from them."

Dr. Prince suggests that information on how to reduce sedentary behavior may benefit heart disease patients taking part in cardiac rehabilitation programs.

Contrary to this and many other studies, research reported by Medical News Today last month suggested that regular exercise can offset the health risks associated with prolonged sitting.

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Can stem cell technology be harnessed to generate biological pacemakers?

Although today's pacemakers are lifesaving electronic devices, they are limited by their artificial nature. For example, their parts can fail or they can become infected. In addition, the devices require regular maintenance, must be replaced periodically, and can only approximate the natural regulation of a heartbeat. A Review article published on November 20 in Trends in Molecular Medicine highlights the promise and limitations of new methods based on stem cell and reprogramming technologies to generate biological pacemakers that might one day replace electronic pacemakers.

Pacemaker Cells
This graphic shows examples of individual pacemaker cells.
Credit: Courtesy of Vasanth Vedantham.

"Theoretically, biological pacemakers, which are composed of electrically active cells that can functionally integrate with the heart, could provide natural heart rhythm regulation without the need for indwelling hardware," says author Vasanth Vedantham, of the University of California, San Francisco.

To create biological pacemakers, one approach is to coax stem cells to become specialized cardiac pacemaker cells that are normally found within the sinoatrial node of the heart. These are then transplanted into an ailing heart to restore pacemaking function. Another promising approach is to directly reprogram supporting cells, already present in the heart--for instance, fibroblasts (e.g., connective tissue)--and convert them into pacemaker cells to restore cardiac function.

Vedantham states that initial large animal studies on biological pacemakers have generated promising results but that much more work remains ahead before biological pacing can be actually considered a clinically viable therapy. For example, researchers need to better understand the mechanisms controlling the development and maintenance of pacemaker cells in the sinoatrial node, just as they must develop ways to compare experimental biological pacemaker tissue with bona fide sinoatrial node tissue. Also, scientists will need to improve the methods used to deliver cells to desired locations within the heart, as well as the recovery of specific individual cells for detailed characterization and functional analyses.

"Biological pacemakers must meet a very high standard of performance to supplant electronic pacemakers," Vedantham says. "Because even a few seconds without a heartbeat can lead to serious consequences, a biological pacemaker would need to exhibit very robust and reliable performance. It remains to be determined whether this will be technically feasible. Despite such challenges, the field is poised for rapid progress over the next few years," he adds.

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Mexico sees heart failure improvements with diet and exercise

Doctors in Mexico have shown the benefits of a healthy diet and exercise in patients with heart failure, in research presented at the Mexican Congress of Cardiology 2015.

The annual congress of the Mexican Society of Cardiology is being held in Acapulco from 21 to 25 November 2015. Experts from the European Society of Cardiology (ESC) will present a special programme.1

Heart failure is a life threatening condition in which the heart is unable to pump enough blood to meet the needs of the body. The typical symptoms are breathlessness, swollen limbs and fatigue.

In Mexico there are 750 000 patients living with heart failure and the problem is growing. It is estimated that 75 000 more patients will get heart failure each year.

"Just 25% of men and 38% of women with heart failure in Mexico will be alive after five years2," said Dr Arturo Orea, study author and cardiology service coordinator at the National Institute of Respiratory Disease (Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas") in Mexico City. "Medication can improve the outcome of heart failure, but for most patients the future is still not very bright."

Dr Orea's previous research shows that 40% of patients with heart failure in Mexico have diabetes, 41% have high cholesterol, 57% have high triglycerides, one-quarter are obese, 55% have high blood pressure, 31% smoke and less than 1% are physically active.3

Regular aerobic exercise is recommended for patients with heart failure to improve symptoms and the ability to do daily activities.4 But more evidence is needed on the benefits of a healthy diet. "There are no specific guidelines on how much carbohydrate, fat and protein patients with heart failure should eat," said Dr Orea. "Sodium and fluid restriction are advised but there are no guidelines on other minerals."

Dr Orea's group has investigated the effect of diet and exercise in patients with heart failure. A study presented for the first time at the Mexican Congress of Cardiology found that after just four months, 84 patients who ate a low carbohydrate diet (40-50% carbohydrates, 30-40% protein and 20% fat) and did aerobic and resistance exercise had reduced blood pressure and total body water compared to a control group of 38 patients.

"These results indicate that a low carbohydrate diet and exercise are beneficial for patients with heart failure," said Dr Orea. "This could be because the respiratory coefficient of carbohydrates is higher than fat and proteins which means they require more oxygen and respiratory effort to metabolise. In addition, a higher intake of unsaturated fat could improve the integrity and function of cells. Exercise improves endothelial function (increasing vessel diameter and blood flow), so there is better delivery of nutrients and oxygen to the cells plus removal of waste."

In another study, the researchers evaluated the impact of sodium, potassium and magnesium ingestion on hospitalisation and death in 129 patients with heart failure over two years.6 Sodium intake was lower in patients who died (837 mg/day versus 1 749 mg/day, p = 0.03). Patients who consumed less than 200 mg/day of magnesium had a nearly three times higher risk of hospitalisation or death.

Dr Orea said: "Patients with heart failure should ensure that they get enough magnesium in their diet by eating dark leafy greens, nuts, fish, whole grains and bananas. Our finding of a lower sodium intake in patients who died might be explained by the fact that when sodium intake reduction is excessive, the renin-angiotensin-aldosterone system is more active, which can increase blood pressure."

Dr Marco A. Peña Duque, president of the Mexican Society of Cardiology, said: "About 20 to 25 years ago the leading cause of heart failure in Mexico was rheumatic heart disease and at present the main cause is ischaemic heart disease. We need to further investigate different treatments to try to reduce mortality from heart failure."

Professor Stephan Achenbach, ESC vice president for Global Affairs and Communications, enthusiastically supported the research performed by Dr Orea and his group: "Heart failure is a growing epidemic across the world and clearly, medication alone is not a sufficient approach. Lifestyle modification must be a central part of management in heart failure patients, not only for treatment but also for prevention. This research helps us understand the effects even better."

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Virtual reality successfully used in cardiac operation

Virtual reality technology, over recent years, has improved in leaps and bounds. Technical difficulties and a prohibitively high price tag have kept it largely under the radar in terms of usable technology, but the tide seems to be turning.
[Artherosclerosis illustration]
Virtual reality was used to insert a stent into a cardiac artery for the first time.

Although certain medical specialities already use Virtual reality (VR) as a training tool, the technology is largely kept out of the operating room.

However, a recent groundbreaking operation might signal the start of VR's increased use within cardiac surgery.

A report published in the Canadian Journal of Cardiology describes a first-in-man procedure using VR and Google Glass technology.

A team of cardiologists from the Institute of Cardiology in Warsaw, Poland, carried out a procedure to reopen a chronically blocked right coronary artery.

The VR procedure was undertaken to fix a chronic total occlusion.

This type of operation is often referred to as the "final frontier in interventional cardiology" because of its unpredictable success rates and the associated difficulties in visualizing the occluded coronary arteries with current technology.

Percutaneous coronary intervention

Percutaneous coronary intervention (PCI) is conducted for patients when coronary arteries have become dangerously narrowed. A catheter with a small balloon attached to the end is inserted into the troubled region through either the arm or groin.

The balloon, guided by real-time X-Ray images, is maneuvered into the troubled region. The surgeon inflates the balloon, reopening the artery. As the balloon is removed, a stent - made of stainless steel mesh - is left in place to permanently hold the blood vessel open.

The operation presents a major challenge for the surgeon. PCI in cases of chronic total occlusion is difficult because of reduced visualization of the affected area using conventional coronary angiography radiology methods.

Coronary computed tomography angiography

Coronary computed tomography angiography (CTA) is a non-invasive way of imaging the coronary arteries using powerful X-rays. In the case of chronic total occlusion operations, CTA is increasingly utilized to provide surgeons with guidance when performing PCI.

The enhanced imaging and 3D capabilities of CTA can be literal lifesavers. However, economic and technical factors currently prevent its common usage.

The cardiologists were able to carry out this groundbreaking operation in a 49-year-old male using CTA projections within a wearable VR device based on Google Glass, with an optical head-mounted display.

Lead investigator Dr. Maksymilian P. Opolski says:

"This case demonstrates the novel application of wearable devices for display of CTA data sets in the catheterization laboratory that can be used for better planning and guidance of interventional procedures, and provides proof of concept that wearable devices can improve operator comfort and procedure efficiency in interventional cardiology."

The technology, designed by the Interdisciplinary Centre for Mathematical and Computational Modeling of the University of Warsaw, also included a hands-free voice recognition system and a zoom function.

Branded a complete success, the procedure included the implantation of two drug-eluting stents (stents that slowly release a drug to block cell proliferation).

This use of VR technology is likely to be the first of many such procedures in the years to come. Any technology that can significantly improve a patient's chance of survival is likely to be well funded and thoroughly investigated.

Dr. Opolski is optimistic about the future advancements of wearable VR technology in the operating room:

"We believe wearable computers have a great potential to optimize percutaneous revascularization, and thus favorably affect interventional cardiologists in their daily clinical activities."

The combined expense of VR technology and CTA currently limits their viability within the health care sector at large. But, as with all technology, prices are sure to slowly reduce, eventually making them available to a wider audience.

Medical News Today recently reported on how VR might be useful in the rehabilitation of stroke patients.

Written by Tim Newman

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