Pacemaker dependency after isolated aortic valve replacement: do conductance disorders recover over time?

OBJECTIVES: Permanent pacemaker (PPM) implantation is required in 3–8% of all patients undergoing aortic valve replacement (AVR). Our aim was to evaluate long-term PPM dependency and recovery of atrioventricular (AV) conduction disorders during follow-up in these patients. METHODS: Since January 1997, a total of 2106 consecutive patients underwent isolated AVR at our institution. Of these, 138 patients (6.6%, 72 female, median age 71 (37–89) years) developed significant conduction disorders leading to PPM implantation postoperatively. Preoperative ECG showed normal sinus rhythm (n= 64), first degree AV block (n= 19), left bundle branch block (n= 13), right bundle branch block (n= 16), left anterior hemiblock (n= 14) and AV block with ventricular escape rhythm (n= 10). Atrial fibrillation was present in 23 patients. Pacemakers were implanted after a median of 7 (1–30) days following AVR. PPM dependency was analysed by ECG and pacemaker check during follow-up. RESULTS: A total of 45 of 138 patients with postoperative PPM Implantation died during a mean follow-up time of 5.3 ± 4.7 years. A further 9 patients were lost to follow-up. Long-term survivals at 1, 5 and 10 years were 88%, 79% and 59%, respectively. Only 8 (10%) of 84 survivors were no longer pacemaker-dependent. The majority of patients (n= 66, 79%) required permanent ventricular stimulation, and the remaining 10 (13%) showed intermittent stimulation with a mean ventricular stimulation fraction of 73% (22–98%). CONCLUSIONS: The majority of patients do not recover from AV conduction disorders after AVR. Since higher-grade AV blocks expose patients to a high risk of sudden death after surgery, we recommend early implantation of permanent pacemaker.