Long-term outcomes after radiofrequency catheter ablation of the atrioventricular node: The experience of a Portuguese tertiary center.

INTRODUCTION: In patients with supraventricular arrhythmias and high ventricular rate, unresponsive to rate and rhythm control therapy or catheter ablation, atrioventricular (AV) node ablation may be performed. OBJECTIVES: To assess long-term outcomes after AV node ablation and to analyze predictors of adverse events. METHODS: We performed a detailed retrospective analysis of all patients who underwent AV node ablation between February 1997 and February 2019, in a single Portuguese tertiary center. RESULTS: A total of 123 patients, mean age 69±9 years and 52% male, underwent AV node ablation. Most of them presented atrial fibrillation at baseline (65%). During a median follow-up of 8.5 years (interquartile range 3.8-11.8), patients improved heart failure (HF) functional class (NYHA class III-IV 46% versus 13%, p=0.001), and there were reductions in hospitalizations due to HF (0.98±1.3 versus 0.28±0.8, p=0.001) and emergency department (ED) visits (1.1±1 versus 0.17±0.7, p=0.0001). There were no device-related complications. Despite permanent pacemaker stimulation, left ventricular ejection fraction did not worsen (47±13% vs. 47%±12, p=0.63). Twenty-eight patients died (23%). The number of ED visits due to HF before AV node ablation was an independent predictor of the composite adverse outcome (OR 1.8, 95% CI 1.24-2.61, p=0.002). CONCLUSIONS: Despite pacemaker dependency, the clinical benefit of AV node ablation persisted at long-term follow-up. The number of ED visits due to HF before AV node ablation was an independent predictor of the composite adverse outcome. AV node ablation should probably be considered earlier in the treatment of patients with supraventricular arrhythmias and HF, especially in cases that are unsuitable for selective ablation of the specific arrhythmia.

Long-term clinical outcomes after upgrade to resynchronization therapy: A propensity score-matched analysis.

BACKGROUND: Upgrade to cardiac resynchronization therapy (CRT) is common in Europe, despite little and conflicting evidence. OBJECTIVE: To compare long-term clinical outcomes in a cohort of patients receiving de novo or upgrade to CRT. METHODS: Single-center retrospective study of 295 consecutive patients submitted to CRT implantation between 2007 and 2018. Upgraded and de novo patients complying with a dedicated follow-up protocol were compared in terms of clinical (NYHA class improvement without major adverse cardiac events [MACE] in the first year of follow-up) and echocardiographic (left ventricle end-systolic volume reduction of >15% during the first year) response. RESULTS: No differences in the rate of clinical (59.3% vs 62.6%, P = .765) or echocardiographic response (72.2% vs 71.9%, P = .970) between groups were observed. Device-related complications were also comparable between groups (8.9% vs 8.4%, P = .892). Occurrence of MACE and all-cause mortality were analyzed over a median follow-up of 3 (interquartile range 1-6) years: MACE occurred less frequently in the de novo group (hazard ratio [HR]: 0.55, 95% confidence interval [CI]: 0.34-0.90, P = .018), but all-cause mortality was similar among groups (HR: 0.87, 95% CI: 0.46-1.64, P = .684). Propensity score-matching analysis was performed to adjust for possible confounder variables. In the propensity-matched samples, all-cause mortality (HR: 1.26, 95% CI: 0.56-2.77, P = .557) and MACE (HR: 0.84, 95% CI: 0.46-1.54, P = .574) were comparable between upgrade and de novo patients. CONCLUSION: Survival after upgrade to resynchronization therapy was comparable to de novo implants. Additionally, clinical and echocardiographic response to CRT in upgraded patients were similar to de novo patients.