Atrioventricular nodal ablation in patients with resynchronization therapy and atrial fibrillation - long term results.

OBJECTIVES: Atrioventricular nodal ablation (AVNA) is recommended for patients (pts) with cardiac resynchronization therapy (CRT) having atrial fibrillation (AF) and incomplete ventricular capture (Class IIa, level B). AVNA reduces mortality and improves the New York Heart Association (NYHA) functional class during intermediate term follow-up. The objectives were to study the long-term outcome regarding quality of life (QoL) and survival of our CRT pts after AVNA. DESIGN: 37 CRT-pts undergoing AVNA due to inadequate biventricular pacing were included in the study. Data were retrospectively obtained from clinical records and through telephone interviews. RESULTS: Twenty pts died during the follow-up period of average 30.6 ± 24 months. After AVNA the ventricular capture improved significantly from 68.4 ± 23% to 98.5 ± 2% (p < 0.001). A significant and sustained improvement of average 0.3 ± 0.5 (p = 0.001) in NYHA functional class was found. Additionally a large percentage of pts discontinued taking rate reducing drugs with potential severe side effects. CONCLUSION: AVNA in CRT pts was safe and effective. The treatment resulted in a sustained improvement in QoL, including long-term improvement in NYHA functional class.

The role of conduction system pacing in patients with atrial fibrillation.

Conduction system pacing (CSP) has emerged as a promising novel delivery method for Cardiac Resynchronisation Therapy (CRT), providing an alternative to conventional biventricular epicardial (BiV) pacing in indicated patients. Despite increasing popularity and widespread uptake, CSP has rarely been specifically examined in patients with atrial fibrillation (AF), a cohort which forms a significant proportion of the heart failure (HF) population. In this review, we first examine the mechanistic evidence for the importance of sinus rhythm (SR) in CSP by allowing adjustment of atrioventricular delays (AVD) to achieve the optimal electrical response, and thus, whether the efficacy of CSP may be significantly attenuated compared to conventional BiV pacing in the presence of AF. We next evaluate the largest clinical body of evidence in this field, related to patients receiving CSP following atrioventricular nodal ablation (AVNA) for AF. Finally, we discuss how future research may be designed to address the vital question of how effective CSP in AF patients is, and the potential hurdles we may face in delivering such studies.

The radiofrequency interference on CRT-D functioning during AV node ablation: An educational case.

We have described some unusual findings of radiofrequency interference with ICD functioning during AV nodal ablation, guiding the reader to the possible explanation of the phenomena.