Some people with heart disease experience a restriction of blood flow to the heart in response to psychological stress. Usually silent (not painful), the temporary restriction in blood flow, called ischemia, is an indicator of greater mortality risk.
Cardiologists at Emory University School of Medicine have discovered that people in this group tend to have higher levels of troponin — a protein whose increased presence in the blood that is a sign of recent damage or stress to the heart muscle– all the time, independently of whether they are experiencing stress or chest pain at that moment.
The results were presented Sunday by cardiology research fellow Muhammad Hammadah, MD at the American College of Cardiology meeting in Chicago, as part of the Young Investigator Awards competition. Hammadah works with Arshed Quyyumi, MD, and Viola Vaccarino, MD, PhD, and colleagues at the Emory Clinical Cardiovascular Research Institute.
â€œElevated troponin levels in patients with coronary artery disease may be a sign that they are experiencing repeated ischemic events in everyday life, with either psychological or physical triggers,â€ Hammadah says.
Doctors test for troponin in the blood to tell whether someone has recently had a heart attack. But the levels seen in this study were lower than those used to diagnose a heart attack: less than a standard cutoff of 26 picograms per milliliter, in a range that only a high-sensitivity test for troponin could detect.
In a separate study, Emory investigators have shown that elevated troponin levels (especially: more than 10 pg/mL)Â predict mortality risk over the next few years in patients undergoing cardiac catheterization, even in those without apparent coronary artery disease.
The stress of public speaking is enough to drive damage-repairing progenitor cells out of the bone marrow into the blood, a study of patients with heart disease has found.
Public speaking raises the blood pressure — it also drives progenitor cells out of the bone marrow
Endothelial progenitor cells (EPCs) are found in the bone marrow, and thought to repair damaged blood vessels once mobilized into the blood by injury or stress. Previous research has shown that strenuous exercise can lead to a dramatic increase in blood EPC levels, but the effects of psychological stress on EPCs had not been examined before.
The new findings were presented Saturday, March 9 at the American College of Cardiology conference in San Francisco. The presenter was cardiovascular research fellow Ronnie Ramadan, MD. Senior authors are Arshed Quyyumi, MD, professor of medicine and director of the Emory Cardiovascular Research Institute, and Viola Vaccarino, MD, PhD, professor and chair of the Department of Epidemiology, Rollins School of Public Health.
In some patients with coronary artery disease, mental stress may precipitate ischemia– a deficiency in blood flow to the heart â€“ a risk factor for adverse events and death independent of other cardiovascular risk factors such as smoking, cholesterol and diabetes.
Poring over the abundance of information presented at major scientific meetings is like trying to drink from a firehose.Â Imposing an Emory-centric filter on this year’s American Heart Association Scientific Sessions meeting in Los Angeles, here are three highlights, with a shoutout to the AHA journal Circulation, which provides a database of meeting abstracts.
Presenter Rebecca Levit, MD, a postdoc in cardiology division chair W. Robert Taylorâ€™s laboratory, was a finalist for an Early Career Investigator Award.
Â Stem cell therapies for myocardial repair have shown promise in preclinical trials, but lower than expected retention and viability of transplanted cells. In an effort to improve this, we employed an alginate encapsulation strategy for human mesenchymal stem cells (hMSCs) and attached them to the heart with a biocompatible PEG hydrogel patch in a rat MI model. Encapsulation allows for diffusion of pro-angiogenic cytokines and growth factors made by the hMSCs while maintaining them at the site of implantationâ€¦Alginate encapsulated hMSCs attached to the heart with a hydrogel patch resulted in a highly significant improvement in left ventricular function after acute myocardial infarction. The mechanism for this markedly enhanced effect appears to be increased cell survival and retention.
Â Note: alginate already has a wide variety of uses, for example in culinary arts and to make dental impressions.
suPAR, a biomarker connected with depression, inflammation and cardiovascular outcomes. Step back, C-reactive protein
A study probing myocardial ischemia (a lack of blood flow to the heart) induced by psychological stress, described in this Emory Public Health article. The presentation by Ronnie Ramadan examines physiological responses to a public speaking test as a way of predicting more severe problems.
Researchers, physicians, and health care providers from across the United States and Italy met recently at the Rollins School of Public Health for the first Emory Conference on Mediterranean Diet and Health. Participants focused on the diet’s relation to cardiovascular disease, cancer, neuropsychiatric disorders, and vascular health.
The Mediterranean diet is characterized by a high consumption of fruits, vegetables, legumes, complex carbohydrates, and nuts; moderate consumption of fish and red wine; low consumption of cheese and red meat; and olive oil as the chief source of fat, explains Viola Vaccarino, MD, PhD, one of the conference chairs.
When topped with exercise, the Mediterranean dietâ€”really a pattern of eating habits traditionally followed by people in the Mediterranean regions in the early 1960sâ€”has proven beneficial for many throughout the years. But why this is so isnâ€™t clear. Read more
Between 1994 and 2006, in-hospital death rates decreased among all patients, but decreased more strikingly in women than in men. The decreased risk of death was largest in women younger than 55 years (a 52.9 percent reduction) and lowest in men of the same age (33.3 percent). The absolute reduction in the risk of death among patients younger than 55 was three times larger in women (2.7 percent) than men (0.9 percent).
Vaccarino and her colleagues say a large part (93 percent) of this sharper decrease in mortality of younger women compared with men in recent years is due to the improved risk profile of women compared with men at the time of the heart attack hospitalization, perhaps the result of better recognition and management of coronary heart disease and its risk factors in women before the acute heart event.
Whatever the reason, the improvement indicates that we are headed in the right direction, says Vaccarino. Increased and ongoing awareness to the prevention of cardiovascular risk factorsâ€”by healthy diet, regular physical activity and avoidance of smoke and smokingâ€”is saving lives, she notes.
Just like diabetes and hypertension, depression is a prevalent medical condition that is highly treatable. However, if ignored, it appears to increase the risk for heart disease. Researchers at Emory are continuing studies related to the link between depression and heart disease as a result of a 2-year, $1.5 million grant from the National Institutes of Health (NIH) through the 2009 American Recovery and Reinvestment Act.
Vaccarino says although depression has been implicated as a risk factor for heart disease for many years, there is still question whether this is a causal association or whether there are other reasons why people who are depressed may be more likely to get heart disease. Clarification of these mechanisms will improve our understanding of the disease and ultimately point to more effective primary prevention strategies for the identification and treatment of high-risk individuals.
Vaccarino and her team will study twin males born between 1946 and 1956 from the Vietnam Era Twin Registry comparing one twin who has depression and one who does not. She says this is almost a natural experiment, allowing researchers to separate out genetics and influences from the environment or behavior.
Vaccarino will be looking at myocardial blood flow measured with PET, a common imaging technique of the heart. It can quantify exactly how much blood is going to the coronary arteries in the heart and carefully determine if depression is associated with decreased blood flow to the heart.
This grant builds on a previous project looking at the same population of twins and allows researchers to bring these twins back and compare two time points. Researchers measured myocardial blood flow with PET a few years ago and will now be able to monitor progression of heart disease over time