Aggressive drugs vs. invasive procedure

Thursday, October 13, 2011 - 9:36am

Heart attacks leave lasting scars. In some patients, these scars can disrupt the flow of electricity through the heart resulting in an irregular heart beat known as ventricular tachycardia (VT).
 
“In VT, the heart can be triggered to start racing out of control,” says Dr. John Sapp, director of Capital Health’s cardiac electrophysiology service. “Left untreated, these people are at high risk of sudden death.”

Danger zone 

Drug therapy and implanted defibrillators can regulate the heart rhythm enough to keep patients out of the danger zone most of the time. But the drugs can have serious side effects, and defibrillator shocks, which return the heart rate to normal, pack a punch of their own.
 
“The impact feels like you’re getting shot,” says Marcel Arbour of Dartmouth, a two-time heart attack survivor who’s had an implanted defibrillator since 2001. “Every time the defibrillator gives me a shock, it knocks me to the ground. I briefly lose consciousness and can’t move for 10 minutes. It’s extremely upsetting and you’re always on edge, wondering when it will happen again.”

A new trial

Arbour was the first patient to enroll in VANISH, a five-year, $2 million international clinical trial led by Dr. Sapp out of Capital Health.

VANISH is comparing the effectiveness of a procedure known as catheter ablation to more-intensive-than-usual drug therapy. He wants to see which approach best controls the erratic rhythms of VT. 

Dr. Sapp has been refining the ablation procedure over the past decade.  In July 2009, he performed ablation on Arbour after a random allocation process.

The five-hour procedure involves inserting tiny wires into the heart, via blood vessels in the leg. Energy is then sent through the wires to cauterize short circuits in the heart’s electrical system.

Aftermath

Two years after the surgery, Arbour calls Dr. Sapp and his electrical team ‘wizards.’

“Less than an hour after the ablation was finished, I felt better than I had in years,” he says. “I haven’t had a single defibrillator shock and I’ve been able to gradually build my strength back up, now that the nerve impulses are flowing more smoothly through my heart.”

Weighing the risks 

Ablation is an invasive procedure and it carries some serious risks. However, the best drugs for regulating heart rhythm don’t always work and the high doses necessary can often cause damage to the lungs, liver, skin and thyroid.

“VANISH will tell us which is the safest and most effective way to reduce shocks and prevent sudden death,” says Dr. Sapp. “Neither is perfect, but we must do something for patients whose VT is not controlled by defibrillator and typical drug therapy.”
 
The VANISH trial is funded by The Canadian Institutes for Health Research and two industry partners, St. Jude Medical Inc. and Biosense Webster.
 

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