Clinical characteristics and long-term follow-up after ablation of right atrial macro-reentrant tachyarrhythmias following surgical repair of congenital and acquired heart disease

Abstract

Introduction: The surgical repair of congenital (CHD) and acquired (AHD) heart disease (both ischemic and valvular heart disease) involves the creation of lines of block that generate a complex pathophysiological substrate, promoting atrial reentry. Radiofrequency catheter ablation (ABL) can treat these atrial tachyarrhythmias. The aim of our study was to describe the long-term follow-up of patients with previous cardiac surgery undergoing right atrial macro-reentrant tachyarrhythmia ablation. Methods: Multicenter study. Clinical characteristics, long-term follow-up and predictors of atrial fibrillation (AFib) development were analyzed. Results: A total of 372 patients were included (69% men), 111 of them had undergone surgical repair of CHD (42% ostium secundum atrial septal defect), while 261 were postoperative of AHD (isolated CABG in 38%, isolated valve disease in 51% and mixed procedures in 11%). Mean age was 61 years (IQ range 52-73y). Cavo-tricuspid isthmus-dependent atrial flutter (CTI-AFL) was observed in 300 patients: 239 (92%) patients with AHD and 61 (55%) patients with CHD; and intra-atrial re-entrant tachycardia (IART) in 72 patients. Ablation was successful in 349 cases (94%) (96% of CTI-AFL and 88% of IART). After a median follow-up of 47 months (IQ 18-73), 119 (32%) patients developed AFib. AFib rates were higher in AHD than CHD patients (35% vs 24%, p=0.04). Hospital admission for heart failure was required in 68 (18%) patients. A total of 55 (15%) patients required pacemaker implantation. At the end of follow-up, 255 (69%) patients were in sinus rhythm and 81 (22%) in AFib. Overall mortality was 15%. Multivariate analysis showed that female gender (HR 2.33, 95% IC 1.59-3.34), surgery for AHD (HR 95% 2.44, 95% IC 1.54-3.87) and left atrial dilation (HR 2.1, 95% IC 1.3-3.2) were independent predictors of long term AFib presentation. Conclusion: Radiofrequency ablation of right atrial macro-reentrant tachyarrhythmias after surgical correction of acquired and congenital heart disease is associated with high rates of acute efficacy. Atrial fibrillation and heart failure were common events during follow-up, especially in patients operated for acquired heart disease and with dilated atrial chambers.