The 40-minute surgical procedure, called left cardiac sympathetic denervation (LCSD), reduces the heart's control from the sympathetic nervous system, which is the part of the nervous system responsible for involuntary biological activity such as breathing and heart rate. "Even in a population of LQTS patients at an especially high risk, denervation surgery reduced syncope (fainting) and cardiac arrest by 91 percent," said Peter J. Schwartz, M.D., professor and chairman of the Department of Cardiology at the University of Pavia in Italy. Long QT syndrome is a disorder of the heart's electrical system. It can be inherited or acquired. The syndrome gets its name from a characteristic, markedly elongated QT interval on an electrocardiogram. People with LQTS are prone to develop an extremely rapid heart rhythm, often brought on by exercise, emotion or loud noise. This improper rhythm interferes with blood flow to the brain and can result in fainting or cardiac arrest.
Symptoms usually occur in childhood or early adulthood, and affect otherwise-healthy people. Symptoms also may appear later in life (often in response to certain medications). The syndrome also may occur in infancy, and may account for a small percentage of sudden infant deaths.
Beta-blockers can slow the heartbeat and prevent arrhythmias in patients with LQTS. However, about a fourth of patients continue to experience fainting spells and potentially life-threatening arrhythmias while on the medication, researchers said. If beta-blockers are ineffective or cause unacceptable side effects, or if a person has already experienced near sudden death, doctors can implant a defibrillator th
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Contact: Carole Bullock
carole.bullock@heart.org
214-706-1279
American Heart Association
29-Mar-2004