Endothelium Roundtable Discussion
The Endothelium and It Role as a Marker of Overall Cardiovascular Health
The PanelistsPeter Ganz, M.D., is the Maurice Eliaser Jr. Distinguished Professor of Medicine and the Chief, Division of Cardiology at the San Francisco General Hospital. Dr. Ganz has been active in translational vascular research. His interests have focused on key aspects of human atherosclerosis including endothelial function. His laboratory pioneered methodological approaches that facilitated testing of coronary and peripheral vascular endothelial function in humans that were first published in the New England Journal of Medicine in 1986 (Ludmer PL, Selwyn AP, Shook TL, Wayne RR, Mudge GH, Alexander RW, Ganz P. Paradoxical vasoconstriction induced by acetylcholine in atherosclerotic arteries. N Engl J Med. 1986;315:1046-1051). This led to a further appreciation of the pathobiology of nitric oxide and endothelin-1 in health and their disturbances in diseases. Dr. Ganz’s work research also contributed to a better understanding of vascular and systemic inflammation and atherosclerotic plaque vulnerability. (In 1998, Drs. Furchgott, Ignarro, and Murad received the Nobel Prize for their discovery of the role of nitric oxide in cardiovascular regulation).
Amir Lerman, M.D., Professor of Medicine at the Mayo Clinic, has been active in cardiovascular research throughout his career. His key interests are interventional cardiology, coronary physiology, intracoronary imaging, and heart failure. His many studies have investigated the role of the endothelium and endothelial-derived factors with emphasis on endothelin and nitric oxide as modulators of coronary vascular tone and in-depth investigation of the role of the endothelium in cardiovascular disease. His pioneering work published in the Journal of the American College of Cardiology in 2004 (Bonetti PO, Pumper GM, Higano ST, Holmes DR Jr, Kuvin JT, Lerman A.) Noninvasive identification of patients with early coronary atherosclerosis by assessment of digital reactive hyperemia. J Am Coll Cardiol. 2004 Dec 7;44(11):2137-41) validated the use of non-invasive EndoPAT testing as an effective diagnostic tool in the diagnosis of patients with endothelial dysfunction and coronary artery disease.
Joseph Vita, M.D., is a Professor of Medicine at Boston University School of Medicine and a senior staff cardiologist in the Section of Cardiovascular Medicine. Over the years, Dr. Vita has been involved in many important studies with cohorts of patients from the Framingham Heart Study. He is a member of the American Society for Clinical Investigation and the Association of University Cardiologists. He is a Fellow of the American College of Cardiology, and the American Heart Association Councils on Arteriosclerosis, Thrombosis, Basic Cardiovascular Sciences and Clinical Cardiology. Dr. Vita is a member of Cardiovascular Diseases Board of the American Board of Internal Medicine. He has served on numerous study sections for the NIH and American Heart Association (AHA) and is a former Chair of the Cardiovascular Pathophysiology Study Section for the AHA. Dr. Vita is a member of the editorial boards of the American Journal of Physiology, Journal of the American College of Cardiology, and Coronary Artery Disease, and currently serves as Deputy Editor of the journal Circulation.
The Mystery of Broken Heart SyndromeDoctors don’t know exactly how stressful events cause heart problems for some people—but they have some very good ideas. The body’s stress hormones, when released in large amounts, may cause a spasm in a coronary artery. There could also be some impact on the endothelium, the lining of the blood vessels, which leads to a narrowing of the arteries that supply the heart with blood. Alternatively, the hormone epinephrine (also known as adrenaline) may bind to the heart cells directly, causing large amounts of calcium to enter the cells and render them temporarily dysfunctional. A study of 19 ABS patients suffering from stress cardiomyopathy, conducted at Johns Hopkins and published in TheNew England Journal of Medicine, reported that during the 12 hours before checking in to the hospital, every one of the patients had experienced some kind of severe emotional stress: a death in the family, an automobile accident, fear over having to speak in public, an intense and angry argument, or even a surprise party. All but one were women, mostly middle aged and older. Testing of the patients showed no blockages or clots in the coronary arteries and no heart damage—what would usually be found after a heart attack. They did all have a heart problem: the left ventricle, the heart’s main pumping chamber, was failing to pump enough blood. In some cases, the condition became life-threatening, leading to heart rhythm abnormalities and heart failure. Additionally, all 19 patients did have high levels of stress hormones in their blood: 7 to 34 times the normal levels of adrenaline. Why older women are the group most vulnerable to stress cardiomyopathy? Some heart experts suspect that it may be that estrogen serves to protect the heart cells from the effects of stress hormones like epinephrine. As women age and their estrogen levels decline, their hearts may become more vulnerable to the effects of stress hormones, particularly in large amounts seen in this syndrome.