The investigators found they could reduce peak shock voltages by an additional 50 percent if they applied shocks between the RV and coronary sinus (CS), a vessel that collects deoxygenated blood from the heart muscle, rather than through the chest wall. Less energy was required because the shocks were confined to the heart itself, and for the same reason they were also less painful.
In an earlier paper, Efimov's student Wenwen Li, PhD, now at St. Jude Medical, had reported on a similar strategy for restoring the rhythm of the atria, the two upper chambers of the heart, for a less serious but more common rhythm abnormality.
The team has already developed the first low-energy atrial defibrillator, which will soon be entering clinical trials. They hope for similarly rapid progress with the ventricular defibrillator.
"We think this technology can and will be implemented soon," says Janardhan. "There's a lot of cardiac research that may pan out 20 or 30 years from now," he says, "but as a physician I want something that can help my patients now."
|Contact: Diana Lutz|
Washington University in St. Louis