THE VALUE OF DDD PACING IN PATIENTS WITH AN IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR

Although the beneficial effects of DDD pacing are well known, currentl y available ICDs provide only fixed rate ventricular antibradycardia p acing. Ln a consecutive series of 139 patients with ICDs, we have anal yzed the need for antibradycardia pacing and the indications fbr DDD p acing. We also report our initial experience with the Defender 9001 (E LA Medical, France) DDD-ICD. Out of 139 patients, 25 (18%) were in nee d of antibradycardia pacing. Ten patients already had a pacemaker at t he time of ICD implantation and ten other patients had a conventional pacemaker indication at that time. Five patients became pacemaker depe ndent during a follow-up of 20+/-8 months. The disorders necessitating pacemaker therapy were high degree AV conduction disturbances in 72%, sick sinus syndrome in 12%, and AF with a slow ventricular response i n 16% of patients. Based upon current indications, DDD pacing was indi cated in 20 (80%) of 25 patients. The Defender 9001 DDD-ICD (ELA Medic al) was used in two patients with ischemic cardiomyopathy and pacemake r syndrome with VVI pacing. Cardiac output during DDD pacing increased by 36% in one patient with an increase in VO2 max during exercise of 29%. The other patient showed an increase in cardiac output of 50% wit h DDD pacing and, while unable to exercise with VVI pacing had a VO2ma x of 24 mL/kg per minute during DDD pacing. Up to 18% of our ICD patie nts are in need of antibradycardia pacing. Of these pacemaker dependen t patients, 80% have an indication for DDD pacing. Our first clinical experience with a DDD-ICD confirms the hemodynamic benefit of AV synch ronous pacing in ICD patients with pacemaker syndrome.