In patients undergoing aortic valve replacement, what factors predict the requirement for permanent pacemaker implantation?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question was to determine what preoperative, perioperative and postoperative factors influence the requirement for permanent pacemaker (PPM) implantation postisolated aortic valve replacement (AVR). Transcatheter aortic valve intervention was not included in this analysis. Using the reported search method outlined below, 705 papers were found. No randomised controlled trials, meta-analyses or registries were identified. Seven single-centre retrospective observational studies represent the best evidence on the subject. The author, journal, date and country of publication, level of evidence, patient group studied, study type, outcomes and results were tabulated. The incidence of PPM implantation following AVR varied from 3.0% to 11.8% (mean 7.0%, median 7.2%). Current best available evidence suggests that baseline evidence of conducting system disease - first degree atrioventricular block (AVB), left anterior hemiblock, right bundle branch block (RBBB) or left bundle branch block (LBBB) is the most powerful independent predictor of PPM requirement following AVR. Other important predictors are surgery for aortic regurgitation, preoperative myocardial infarction and longer perioperative cardiopulmonary bypass time. No consistent postoperative factors were identified. The mean time to PPM implant postAVR ranged from 6 to 13 days in the four studies that reported it. Current European Society of Cardiology guidelines recommend a period of seven days of persistent AVB postsurgery prior to PPM implantation.