Pacemaker implantation after cardiac surgery: a contemporary, nationwide perspective

Background Cardiac surgery carries a heightened risk of bradyarrhythmias, but current permanent pacemaker (PPM) implantation estimates rely on non-contemporary studies. This study primarily aimed to explore the incidence and indications for PPM implantation at 30 days and 1 year after different cardiac surgical procedures in a modern cohort. Secondary outcomes were PPM incidence at 10 years and time from cardiac surgery to PPM implantation. Methods This nationwide population-based study included all patients in Sweden who from 2006 to 2020 underwent first-time coronary artery bypass grafting (CABG) and/or valvular surgery. Patients with previous PPM, previous or later implantable cardioverter-defibrillator (ICD) and those who underwent heart transplantation were excluded. Results Overall, 76 447 patients were included, out of which 8.2% (n=6271) received a PPM. The cumulative incidence of PPM implantation was 2.9%, 3.8% and 9.5% at 30 days, 1 year and 10 years following cardiac surgery, respectively. The main PPM indication was atrioventricular block. Tricuspid valve surgery exhibited the highest cumulative incidence for PPM both at 30 days (6.8%, 95% CI 4.3% to 10.0%) and 1 year (8.8%, 95% CI 6.0% to 12.0%) surpassing mitral valve surgery (30 day 5.3%, 95% CI 4.7% to 6.0%; 1 year 6.5%, 95% CI 5.8% to 7.3%), aortic valve surgery (30 day 4.8%, 95% CI 4.5% to 5.1%; 1 year 6.0%, 95% CI 5.6% to 6.3%) and CABG (30 day 0.74%, 95% CI 0.6% to 0.8%; 1 year 1.3%, 95% CI 1.2% to 1.3%). The incidence following combined operations (multiple valves and/or CABG) was 6.5% (95% CI 6.0% to 6.9%) and 8.1% (95% CI 7.7% to 8.6%) at 30 days and 1 year, respectively. Concomitant ablation surgery increased the risk even further (adjusted HR 9.2, 95% CI 7.9 to 10.6; p<0.001). Conclusions The need for PPM after cardiac surgery is substantial, primarily due to atrioventricular block. Tricuspid valve surgery is associated with the highest risk for PPM among isolated procedures. Combined procedures and concomitant surgical ablation further increase that risk.