Introduction: There is increasing evidence of the epicardial connection
between the right-sided pulmonary vein (PV) carina and right atrium
interrupts right-sided PV isolation after circumferential PV ablation in
patients with atrial fibrillation. In such cases, carina ablation is
often required. This study aimed to assess the utility of the right
atrial posterior wall (RAPW) pacing in the detection of the right-sided
epicardial connection (EC), evaluate the requirement for additional
carina ablation after circumferential pulmonary vein (PV) ablation
depending on the presence of EC, and investigate the clinical
characteristics including the amount of epicardial adipose tissue (EAT)
in patients with ECs. Methods and Results: Forty-one patients scheduled
for PV isolation were enrolled. Before ablation, activation mapping of
the LA was prospectively performed during pacing from the RAPW. EC was
observed in 12 patients (EC group, 29%), whereas no EC was observed in
the remaining 29 patients (non-EC group, 71%). For PV isolation, carina
ablation was required in addition to circumferential ablation in 7
patients (58%) in the EC group, compared to 2 patients (7%) in the
non-EC group (p < 0.003). Periatrial and intercaval EAT
volumes were significantly lower (12.8 ± 6.2 vs. 23.1 ± 13.9 ml/m
, p < 0.02, and 1.1 ± 0.8 vs. 2.2 ± 1.6
ml/m , p< 0.02, respectively) and the
patients were younger (66.5 ± 6.6 vs. 72.4 ± 8.3 years, p <
0.03) in the EC group than in the non-EC group. Conclusions: RAPW pacing
revealed EC between the RA and right PV carina in nearly a quarter of
the patients.
Technique for detecting an electrical connection between the right atrium and right pulmonary venous carina