Incidence and risk factors for permanent pacemaker implantation following aortic root surgery

BACKGROUND: Permanent pacemaker implantation (PPI) remains a serious complication following aortic root replacement (ARR) and valve-sparing root replacement (VSRR). This is due to the proximity of the atrioventricular node and the bundle of His to the aortic valve annulus and the left ventricle. The data regarding PPI after aortic root surgery are sparse. We describe the incidence, indication and timing of PPI following conventional ARR and VSRR. METHODS: 727 consecutive patients undergoing elective and urgent aortic root surgery (549 ARR, 178 VSRR) between 2006-2023 were studied. Patients requiring PPI after aortic root surgery were identified, along with the indication and timing. The primary endpoint was the incidence of new PPI implantation during index hospital admission. RESULTS: The incidence of PPI was 1.8% (n=13), with incidences in the ARR and VSRR groups of 2.2% vs 0.6% respectively. PPIs were performed at a median of 9 days (range 3-14 days). Following ARR, PPIs were primarily indicated for complete heart block (67%). In the PPI group, 53% had bicuspid aortic valve (BAV), 62% were female and 62% had preoperative atrial fibrillation. The median follow-up was 7.6 years (range 0.5-14.5). CONCLUSIONS: Conventional aortic root and valve sparing surgery carries a low risk of PPI (1.8%), particularly after VSRR. This study provides contemporary evidence of the risk of PPI requirement. BAV and female gender were associated with an increased risk of PPI.