" Hi, my name is Boris Schmidt. I'm an interventional electrophysiologist from Frankfurt, Germany, and my hospital is CCB.

Study Overview

Today we will be discussing the results of the ASTRO trials. ASTRO stands for Ablation Strategies in Patients with Atrial Fibrillation Despite Durably Isolated Pulmonary Veins. Despite technological advancements, a considerable number of patients still suffer from atrial fibrillation after a catheter ablation. When patients return for repeat catheter ablation and the operator finds all pulmonary veins isolated, there is a lack of data regarding the appropriate and most successful ablation strategy.

Study Design

In a German multicenter prospective randomised study, we screened more than 300 patients with atrial fibrillation after one or more catheter ablations and after confirming pulmonary vein isolation. We randomised these patients to either an individualised strategy with voltage-guided catheter ablation using irrigated radiofrequency current or an empirical strategy isolating the left atrial appendage with the cryoballoon followed by interventional closure. Among the patients investigated, two-thirds had persistent atrial fibrillation and one-third had paroxysmal atrial fibrillation.

Key Findings

Today at EHRA, we will present the data of the ASTRO trial. The main finding is that there was no statistically significant difference between the two approaches, and we could not confirm the hypothesis that left atrial appendage isolation using the cryoballoon is superior to a voltage-guided ablation.

Conclusion

The key take-home message for me is that to date, we still do not have the answer to what is the most optimal ablation strategy for patients with durably isolated pulmonary veins still suffering from atrial fibrillation. Incorporating new technology, we need to continue our research in this field.

Future Implications

Given the results, with numerically fewer complications in the substrate-based ablation approach, it is very unlikely that empirical left atrial appendage isolation will enter guideline recommendations as a first-line therapeutic approach for this patient population. The most compelling question that remains is how can we find an appropriate strategy for patients with durably isolated veins still suffering from atrial fibrillation? Future research is needed to understand atrial fibrillation mechanisms and develop more durable ablation strategies for these patients.”