Other pacing research : Some researchers are exploring different options for biventricular pacing. For example, one of the inclusion criteria for the VIGOR CHF trial is that patients have BBB. Dr. Saxon mentioned, however, that there is no firm consensus as to whether BBB is a necessary criterion for biventricular pacing. She and her colleagues are conducting other acute studies to determine if patients with no overt BBB can improve with biventricular pacing.
"There are also many questions about how biventricular pacing should be applied," she pointed out. "For instance, no one knows the precise location of the ideal LV pacing site. It could be the LV apex, the far lateral wall or closer to the base of the heart. Researchers are also wondering which is more important in reducing CHF symptoms: finding the best LV pacing site or pacing both ventricles. And other investigators are focusing solely on the timing of ventricular activation – whether it’s better to pace both ventricles simultaneously or to delay pacing one ventricle by several milliseconds."
Dr. Saxon explained that while biventricular pacing is the area of most intense interest right now, researchers are continuing to explore other types of pacing to treat CHF. "Whereas a standard dual-chamber pacemaker paces the right atrium, some experimental systems are using left atrial dual-chamber pacing via the coronary sinus. No data have yet been published on this approach, though." (guidant.com)