A 40-minute procedure called left cardiac sympathetic denervation (LCSD) can reduce sympathetic nervous system to the heart and reduce risk for syncope or sudden death in young people with long QT syndrome, according to an article in the March 30th rapid access issue of Circulation.

“Even in a population of [long QT syndrome] patients at an especially high risk, denervation surgery reduced syncope and cardiac arrest by 91 percent,” said Peter J. Schwartz, MD, lead author of the study.

Roughly 25 percent of patients treated with beta-blockers continue to have syncopal spells and potentially life-threatening arrhythmias, according to the researchers. If beta-blocker treatment is unsuccessful or a person has already experienced near sudden death, doctors can implant a defibrillator. Schwartz said defibrillators provide the best protection, but bursts of arrhythmia requiring multiple shocks can frighten patients and seriously lower quality of life.

In the current study, the Italian group identified 147 young patients (69 percent female, average age 17 years) whose initial syncopal event occurred at an average age of 8 years. The patients were considered high risk because their QT intervals were extremely prolonged and they had experienced cardiac arrest (48 percent) or continued to have symptoms despite taking beta-blockers (75 percent). All underwent the denervation procedure at a single center.

An average of 7.8 years after surgery, the number of cardiac events per patient per year dropped by 91 percent compared with pre-surgery rates. During the follow-up period, 46 percent of the patients had no symptoms, 31 percent lost consciousness at least once, 16 percent had a cardiac arrest, and 7 percent had sudden cardiac death.

“For patients who have a fainting episode while on beta-blockers, left cardiac sympathetic denervation is a valid alternative to the immediate implantation of a defibrillator,” Schwartz said. “A defibrillator could still be implanted in those who, after surgery, continue to have a prolonged QT interval or who have another recurrence.”

“Left cardiac sympathetic denervation is one more option available to patients and physicians in their search for the best individually tailored therapy. All advantages and limitations should be weighed and discussed, and it is essential to remind people that with [the procedure] there is some excess risk for fatal events compared to the implantable cardiac defibrillator.”

In 5 patients who experienced multiple shocks from their implantable defibrillators, surgery reduced the average number of shocks from 29.3 to 3.3 per year, according to the report.

“Just imagine what that means for young patients and for their parents who have to helplessly watch during the shocks. We as physicians should always remember that quality of life, and not only duration, is extremely important,” Schwartz said.