Pacemaker Selection — The Changing Definition of Physiologic Pacing

Almost 50 years after the first report of the use of cardiac pacing, in the Journal, 1 pacing is playing an increasingly important role in the management of cardiac disease. Cardiologists have evaluated single-chamber, dual-chamber, and triple-chamber pacemakers in patients with different types of conduction-system disease and underlying cardiac function. The goal of these increasingly complex pacing systems is to reproduce the normal electrical activation of the heart.Dual-chamber pacing confers potentially important hemodynamic advantages over ventricular pacing by linking the timing of atrial and ventricular contraction, a phenomenon called atrioventricular synchrony.2 In short-term and long-term studies, atrioventricular synchrony improves stroke . . .