College Celebrates Cardiovascular Research during Heart Month
- By Jennifer Nachbur
Just over a year ago, the American Heart Association (AHA) announced its new impact goal to “by 2020, improve the cardiovascular health of all Americans by 20 percent while reducing deaths from cardiovascular diseases and stroke by 20 percent.” That’s a tall order considering that 82 million American adults – one in three people – have one or more types of cardiovascular disease. But investigators worldwide, including dozens of University of Vermont College of Medicine faculty members, are working towards achieving this goal, examining a wide range of cardiovascular disease- and treatment-related questions. New details about such issues as obesity, exercise, ethnic differences, gender differences and treatments are among the many study findings published and/or presented by UVM researchers in professional journals and at national meetings in the past year.
A few of those faculty and studies include:
Philip Ades, M.D.: Knowing that obesity is an independent risk factor for coronary heart disease (CHD) and more than 80 percent of patients entering cardiac rehabilitation programs are overweight, Ades and colleagues have continued to evaluate the value of specific exercise training protocols in overweight patients, in particular, high-caloric expenditure exercise (longer distance walking). Their results support the inclusion of weight loss programs in cardiac rehabilitation programs, which are often prescribed following a cardiac event, but generally lack this component. Their recent studies have found that “the risk factor benefits of weight loss and exercise training in overweight CHD patients are broad and compelling. Improvements in insulin resistance, lipid profiles, blood pressure, clotting abnormalities, endothelial-dependent vasodilatory capacity, and measures of inflammation such as C-reactive protein have all been demonstrated.”
Mary Cushman, M.D.: As part of a national collaborative research group, Cushman and colleagues are working on discovering reasons why African-Americans have higher stroke mortality than whites in the United States and have presented several interesting findings in the past year that provide several clues. According to their reports, incidence, not just death rate after a stroke, contributes to the racial disparity, and standard stroke risk factors – hypertension, smoking and diabetes, along with socioeconomic factors – explains about half of the disparity, by virtue of the higher burden of these risk factors in African-Americans than whites. In addition, Cushman and colleagues discovered that African-Americans have higher levels of low grade inflammation, known to be a stroke risk factor, and attributed about 15 percent of the excess risk to higher levels of C-reactive protein, a circulating marker of inflammation. Their research also showed that only 29 percent of the U.S. population can be classified as having at least four of seven key health factors at ideal status, based on definitions proposed by the AHA. The profile for ideal health was worse in African-Americans than whites, and further, ideal health status was strongly related to mortality risk. For more information on the AHA’s Life’s Simple Seven, visit http://mylifecheck.heart.org/Multitab.aspx?NavID=3&CultureCode=en-US
Harold Dauerman, M.D.: According to Dauerman and colleagues, bleeding and vascular complications remain more common in women than men undergoing invasive cardiovascular procedures. From 2004 to 2009, the research team identified all major bleeding and vascular complications among women undergoing diagnostic or interventional cardiovascular procedures at a single center. They examined the role of femoral angiographic variables in risk-stratifying women for vascular complications and determined that women with smaller femoral arteries are at significantly higher risk for bleeding and vascular complications than women with larger femoral arteries. The group suggests that risk stratification for bleeding complications among women should account for clinical, pharmacologic and femoral angiographic factors. In addition, Dauerman and a colleague at Beth Israel Deaconess Medical Center in Boston, Mass., are co-leading a national trial looking at how long patients should be on aspirin and clopidogrel (also known as Plavix) after drug eluting stenting – a treatment for blocked arteries – and what circumstances contribute to patients stopping their medications early.
Martin LeWinter, M.D.: About 5.7 million people in the United States have heart failure, a disorder in which the heart does not pump blood adequately. Among the serious problems caused by heart failure are reduced blood flow throughout the body, congestion of blood in the veins and lungs, and fluid accumulation in various organs and limbs. Diuretics – medications that reduce fluid retention – are often used to treat fluid accumulation, but the best timing and dosage of this therapy is not well-defined. LeWinter, who currently serves as principle investigator on a National Heart Lung and Blood Institute-supported Regional Clinical Center of the Heart Failure Clinical Research Network in northern New England, New York and Quebec, Canada, and colleagues compared high and low doses of diuretics administered over longer and shorter periods of time to determine the safest and most effective combination. This first major trial of a national heart failure consortium – called DOSE (Diuretic Optimal Strategy Evaluation in Acute Heart Failure) – found that treating patients with worsening heart failure with intermittent, quickly administered doses of the diuretic furosemide (Lasix) was as effective as continuous infusion of the medication. The study findings were presented at the 2010 American College of Cardiology Annual Scientific Session and are due to be published in the New England Journal of Medicine in the near future.