A Prospective Registry of Atrial Fibrillation Ablation with the Ablation Index Technology: Rationale and Study Design.

This is a prospective multicenter registry of atrial fibrillation (AF) ablation with the Ablation Index (AI) technology, which has been introduced as a marker predicting ablation lesion depth. The index incorporates the main parameters of radiofrequency point-by-point ablation: power, contact force, and time of ablation. The AI is calculated for every operator depending on personal skills, and there are no strict indications on the range of the parameter considering its safety and efficacy during pulmonary vein isolation. The registry aims to evaluate AI values used in different centers by different operators and to evaluate the optimal limits associated with better acute and long-term AF ablation results.

Performance of the ablation index during pulmonary vein isolation: periprocedural data from a multicenter registry.

PURPOSE: Our study aimed to assess the achievement of target ablation index (AI) values and their impact on first-pass pulmonary vein isolation (FPI) as well as to identify FPI predictors. METHODS: Atrial fibrillation (AF) ablation was performed according to the local practice, and target AIs were evaluated. The actual AI was calculated as the median value of all ablation points for the anterior and posterior left atrial (LA) walls. RESULTS: A total of 450 patients from nine centers were enrolled. Patients with first-time ablation (n = 408) were divided into the FPI and non-FPI groups. In the FPI group, a higher median target AI was reported for both the anterior and posterior LA walls than those in the non-FPI group. A higher actual AI was observed for the anterior LA wall in the FPI group. The actual AI was equal to or higher than the target AI for the posterior, anterior, and both LA walls in 54%, 47%, and 35% (n = 158) cases, respectively. Parameters such as hypertension, stroke, ablation power, actual AI value on the anterior wall, target AI values on both LA walls, AI achievement on the posterior wall, carina ablation, and operator experience were all associated with FPI in a univariate logistic regression model; only carina ablation was an independent predictor of FPI. CONCLUSIONS: According to our multicenter study, FPI and a target AI were not achieved in a significant proportion of AF ablation procedures. Higher actual and target AI values were associated with FPI, but only carina ablation can independently predict FPI.