DDD pacing: clinical considerations.

DDD pacemakers offer a physiologic form of pacing for selected patients by incorporating atrioventricular synchrony over a wide range of atrial rates. Selection of a patient for DDD pacing necessitates a thorough knowledge of the individual functions of the DDD pacemaker, the limitations of DDD pacing, and the patient's own electrical and physiologic needs. Continuing developments in cardiac pacing include further reduction of the possibility of pacemaker-mediated tachycardia, increased matching to metabolic needs, and advancement of telemetric technology and electrophysiologic testing.