Prognostic impact of 1-year permanent pacemaker implantation after mitral valve surgery with the Cox-maze procedure

OBJECTIVES: This study aimed to evaluate the prognostic impact of permanent pacemaker (PPM) implantation within the first year after mitral valve (MV) surgery combined with the Cox-maze procedure, focusing on long-term outcomes, including overall mortality, infective endocarditis (IE) and ischaemic stroke. METHODS: We conducted a retrospective cohort study using data from the National Health Insurance Service (NHIS) in South Korea, identifying 10 127 patients who underwent MV surgery with the Cox-maze procedure between 2005 and 2020. Patients were classified into the PPM and non-PPM groups based on PPM implantation within 1 year postoperatively. The primary outcome was overall mortality, and secondary outcomes included risk factors for overall mortality, IE and ischaemic stroke. Multivariable Cox proportional hazards regression and Fine-Gray competing risk models were utilized for statistical analysis. RESULTS: Of the total cohort, 178 patients (1.76%) underwent PPM implantation. The overall mortality during the follow-up period was 20.5%, with no significant difference between the PPM and non-PPM groups. PPM implantation was not a significant risk factor for overall mortality (hazard ratio [HR], 0.825; 95% confidence interval [CI] 0.598-1.140; P = 0.244) or ischaemic stroke. However, PPM implantation was associated with a significantly increased risk of IE (HR, 2.015; 95% CI 1.179-3.442; P = 0.010). CONCLUSIONS: PPM implantation within the first year after MV surgery with the Cox-maze procedure does not significantly impact long-term mortality or ischaemic stroke risk but is associated with an increased risk of IE. The Cox-maze procedure remains advisable for patients with atrial fibrillation undergoing MV surgery.