Adverse Interactions between ICD and Permanent Pacemaker Systems

After the introduction of the implantable cardioverter defibrillator (ICD) in clinical practice by Mirowski in 1980 [Mirowski et al., 1980] the first available devices offered only a basic ventricular pacing option. Since approximately 5-20% of patients with an indication for ICD therapy following implantation criteria at that time (secondary prevention) needed antibradycardia pacing as well, the implantation of an additional pacemaker (PM) was often necessary up to the 1990s [Sticherling et al., 1997; Brooks et al, 1995; Geiger et al., 1997]. In contrast, the modern ICD systems offer all forms of antitachycardia and antibradycardia therapy integrated in one device. However in 1997 Sticherling et al. concluded in their review about combined ICD and antibradycardia pacing therapy, that even with the introduction of integrated devices the issue of interactions will stay clinically relevant, as many candidates for ICD implantation present with an already implanted pacemaker system [Sticherling et al., 1997]. In contrast to this prediction, today more than 10 years later, through the tremendous advances in device technology as well as in implantation and revision operation methods, the patients are rare, who are fitted with two separate active cardiac implantable electronic devices (CIED) for antibradycardia and antitachycardia therapy respectively. However these patients require extreme diligence at implantation, testing, programming and follow-up to avoid potentially dangerous interactions between the devices. „Concomitant implantation of AICD and a permanent pacemaker requires an understanding of the functioning of both devices and their potential interactions“[Singer et al., 1988]