Sinus node dysfunction after surgical atrial fibrillation ablation with concomitant mitral valve surgery: Determinants and clinical outcomes

OBJECTIVE: We sought to investigate determinants and prognosis of sinus node dysfunction (SND) after surgical ablation of atrial fibrillation (AF) with concomitant mitral valve (MV) surgery. A total of 202 patients who underwent surgical AF ablation with concomitant MV surgery were studied. STUDY DESIGN AND SETTING: SND was defined as electrocardiographic manifestations, such as junctional bradycardia, symptomatic sick sinus syndrome, or symptomatic sinus bradycardia, 7 days after surgery. Baseline clinical and echocardiographic characteristics, rhythm outcomes [AF recurrence or permanent pacemaker (PM) implantation] at 6 and 12 months, and clinical outcomes were compared between patients without SND (n = 165) and those with SND (n = 37) after surgery. RESULTS: Patients with SND showed a significantly larger left atrial volume index (LAVI) and a higher right ventricular systolic pressure than those without SND. In addition, there was a higher likelihood for AF recurrence and PM implantation in patients with SND than in those without SND. Although clinical outcomes did not differ between the two groups, patients with SND had a significantly longer length of hospital stay (p<0.001). In a multivariate analysis, preoperative LAVI was a structural risk factor for SND [hazard ratio (HR): 1.126 per 10 mL/m(2); 95% confidence interval (CI): 1.0206–1.236; p = 0.001]. An LAVI cut-off value of 105 mL/m(2) showed significant predictive power for SND [sensitivity: 62%; specificity: 64%; area under the curve (AUC): 0.678; p = 0.002]. CONCLUSIONS: In conclusion, preoperative LA size was a structural risk factor for SND after surgical AF ablation during MV surgery. SND was associated with an increased risk for AF recurrence and implantation of permanent PM in patients undergoing concomitant surgical ablation of AF with MV surgery.