Background: The effectiveness of radiofrequency catheter ablation (RFCA) in atrial tachyarrhythmias correlates with lesion transmurality. Ablation Index (AI) is an index that incorporates contact force, time, and radiofrequency power simultaneously and is able to predict lesion size and outcomes in RFCA of atrial fibrillation.
Objective: The purpose of this study was to assess whether AI could be an acute and long-term success predictor in RFCA of premature ventricular complexes (PVCs).
Methods: One hundred forty-five patients with idiopathic outflow tract PVCs undergoing RFCA were retrospectively enrolled. The maximum and maximum AI values were calculated for each ablation site. Acute and 6-month outcomes were analyzed. Patients were divided into 3 outcome subgroups—success, acute failure, and 6-month failure—and the maximum and mean AI values were compared.
Results: Acute and 6-month success rates were 95% and 77%, respectively. The maximum and mean AI values were statistically higher in the success group (median of the maximum AI 630; median of the mean AI 489) than in the acute failure group (median of the maximum AI 487; median of the mean AI 372; P < .0001 for both) and the 6-month failure group (median of the maximum AI 519; median of the mean AI 410; P < .0001 for both). Both maximum and mean AI values were confirmed to be statistically higher in the success group than in the failure/6-month failure group and also in septum (P = .001 and P = .04, respectively) and right ventricular free wall (P = .007 and P = .01, respectively) PVC origin subgroups.
Conclusion: Our data support the concept that AI could be a long-term success predictor in RFCA of PVCs. However, further prospective studies are required to assess the feasibility of the AI-guided PVC ablation approach.