Clinical impact of permanent pacemaker implantation following surgical ablation of atrial fibrillation concomitant to mitral valve surgery: a multicenter study

Abstract Background Permanent pacemaker (PPM) implantation is a common adverse event following arrhythmia surgery. However, the epidemiology and clinical impact of PPM has been shown in only few studies in heterogeneous population, and the results are controversial. Purpose The present study aimed to investigate the clinical impact of PPM implantation following surgical ablation of atrial fibrillation (AF) concomitant to mitral valve (MV) surgery. Methods We identified 721 patients (aged 60.2±11.0 years, 437 females) who underwent surgical ablation of AF along with MV repair or replacement at five representative institutions in Korea between 2005 and 2017. Of these, 56 had PPM implanted (PPM group) and the remainder (n=665) did not receive a PPM (No-PPM group). The clinical outcomes were compared between the groups, and multivariable Cox proportional hazard analysis with time-varying covariate was conducted to determine the impact of PPM implantation on mortality and stroke. Results The patients in the PPM group were older, and had a higher CHAD2S2-VASc score than those in the No-PPM group (Table). During follow-up of 68.3 months (interquartile range 44.5-105.4 months), no significant survival difference was evident between the groups, however, the PPM group presented a significantly higher incidence of stroke than No-PPM group (p<0.001) (Figure). On time-varying multivariable analysis, the PPM was not a risk factor for mortality (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.18-1.08; p=0.072), however, old age (HR, 1.10; 95% CI, 1.07-1.13; p<0.001), chronic kidney disease (HR, 1.61; 95% CI, 1.01-2.58; p=0.046) and previous cardiac surgery (HR, 1.86; 95% CI, 1.01-3.21; p=0.027) were independent predictors of mortality in this subset of patients. The only significant risk factor for stroke was CHAD2S2-VASc score (HR, 1.27; 95% CI, 1.01-1.61; p=0.044), and PPM was not associated with risk of stroke (HR, 1.87; 95% CI, 0.71-4.90; p=0.202). Conclusion PPM implantation following surgical ablation of AF concomitant to MV surgery was not associated with an increased risk of mortality or stroke. This study result provides a supporting evidence for an active attempt in surgical ablation despite of inherent risk of PPM implantation.