MONDAY, March 29, 2004 (HealthDayNews) -- Cutting part of the nerves to the heart reduces the risk of fainting or sudden death in young people with a rare heart rhythm disorder called long QT syndrome (LQTS).
That's what Italian researchers report in the March 29 online issue of Circulation.
The 40-minute surgery, called left cardiac sympathetic denervation (LCSD), reduces the sympathetic nervous system's control on the heart. The sympathetic nervous system is responsible for involuntary 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 arrrest by 91 percent," Dr. Peter J. Schwartz, professor and chairman of the department of cardiology at the University of Pavia, says in a prepared statement.
LQTS, which can be inherited or acquired, is a disorder of the heart's electrical system that makes people prone to develop an extremely rapid heart rhythm. This improper rhythm, which can be brought on by exercise, emotion or loud noise, interferes with blood flow to the brain. It can lead to fainting or cardiac arrest.
The study included 147 patients, average age 17, who had LCSD between 1970 and 2002. At an average of 7.8 years after surgery, the number of cardiac events per patient dropped by 91 percent compared to pre-surgery rates.
During the follow-up period after surgery, 46 percent of the patients had no LQTS symptoms, 31 percent lost consciousness one or more times, 16 percent suffered cardiac arrest, and 7 percent had sudden cardiac death.
This surgery offers another treatment option for people with LQTS, the researchers say.
Beta blockers can slow the heartbeat and prevent arrhythmia in people with LQTS. If beta blockers aren't effective or cause serious side effects, a defibrillator can be implanted to maintain normal heart rhythm.
More information
The Congenital Heart Information Network has more about sudden cardiac death.
