Stratifying risk of recurrence of atrial fibrillation following balloon cryoablation using the CAAP-AF risk scoring system

Abstract

Objective: To determine if the CAAP-AF tool could be applied to a cohort of patients in the United States undergoing cryoablation or AF utilizing second-generation cryoballoons.

Background: Atrial fibrillation (AF) is a major source of morbidity and expense, with over 33 million individuals affected worldwide and over 450 000 hospitalizations annually in the United States. Catheter ablation for AF is a class I indication for patients with symptomatic AF. The ability to predict postablation recurrence would have an enormous impact on both patient outcomes and cost to the health care system.

Methods: Our study was an observational, single-center retrospective study to evaluate the utility of the CAAP-AF risk scoring system in predicting recurrence of AF following second-generation balloon cryoablation for AF.

Results: There were a total of 235 patients. From the initial cohort, 30.2% (71) had a recurrence of AF within 1 year of the cryoablation procedure. There was a statistically significant increase in mean age, left atrial diameter, left atrial volume index, CHADS₂ , CHADS₂ -VASc, and number of antiarrhythmics failed in the group that had recurrence of AF. There was also a statistically significant increase in the CAAP-AF score in patients who had recurrence of AF.

Conclusions: The CAAP-AF score predicted the freedom from AF 1 year following cryoablation for AF. The CAAP-AF score can aid in selecting patients most likely to benefit from cryoablation, which includes patients with a low CAAP-AF score, as they are most likely to remain AF free at 1 year.

Keywords: CAAP-AF; atrial fibrillation; catheter ablation; cryoablation; cryoballoon; recurrence.