Background:

While pulmonary vein isolation (PVI) is considered safe and well established to treat symptomatic atrial fibrillation (AF), previous studies implicate increased complication-rates and reduced efficacy of PVI in obese patients. However, this patient group represents a collective in which the prevalence of AF is increased and antiarrhythmic drugs seem to be less effective. Therefore, this study aimed at investigating the safety and efficacy of PVI between obese and non-obese patients from our tertiary center.

Methods and Results:

In the obesity-group 111 patients with a Body-Mass-Index (BMI) >30kg/m² (average BMI: 34.3±3.4) were analyzed. This collective was compared to a matched group of non-obese (BMI <30 kg/m²) PVI-patients (n=106; average BMI: 25.9±2.3) from our PVI-registry. In both groups, AF-characteristics did not significantly differ (obese: 54.9% persistent AF; control: 48.4% persistent AF), while known risk factors e.g. arterial hypertension, coronary artery disease, diabetes, and left atrial dilatation were significantly more prevalent in the obesity group. Procedural characteristics were almost similar in both groups (obese: cryoballoon-isolation (Cryo): 49.5%, radiofrequency-ablation (RF): 19.3%, phased-RF-ablation (PVAC): 28.4%; Re-Do: 21.1%; control: Cryo: 59.6%, RF: 14.7%, PVAC: 24.8%, Re-Do: 22%) and acute ablation success defined as complete PVI with sinus rhythm at the end of the ablation procedure was 98% in both groups. Furthermore, severe complications (stroke, pericardial tamponade, and phrenic lesion) were rare in both groups (obese: n=3; control: n=2) and procedure-times did not significantly differ between the groups (117.4±47.7min vs. 109.0±44.4min p=ns.). Notably, radiation dose was around 2.4-fold higher compared to the radiation dose in non-obese patients (2360.8±1759.6 cGy/m² vs. 989.7±756.2 cGy/m² p<0.01).

Conclusion: PVI is safe and effective in obese patients and further data are needed to evaluate the long-term effects of PVI in this collective. Of note, optimal radiation protection is of special importance when performing PVI in obese patients.