Predictors of arrhythmia recurrence after balloon cryoablation of atrial fibrillation: the value of CAAP-AF risk scoring system

In the present study, we aimed to test the value of CAAP-AF score for prediction of atrial fibrillation (AF) recurrence at follow-up in a group of our patients treated by balloon cryoablation. A total of 283 symptomatic drug-refractory AF patients [261 (92%) with paroxysmal AF] who underwent pulmonary vein isolation (PVI) with second-generation cryoballoon between April 2012 and October 2016 were included. The CAAP-AF score was calculated for every patient. A total of 283 patients [68 female (20%), mean age 59.8 +/- 11.4 years] were included in the present analysis. Eighty-nine patients (31%) had hypertension and 13 (4%) had coronary artery disease. The mean left atrial diameter and left ventricular ejection fraction were 40.6 +/- 7.0 mm and 60.0 +/- 9.1%, respectively. The mean CHA(2)DS(2)-VASc score was 1.2 +/- 1.1, and mean number of prior failed antiarrhythmic drugs was 1.4 +/- 0.8. At 18 +/- 6 months follow-up, 25 patients (8.87%) developed AF recurrence. The recurrence rate was as follows: 3.17% (score 0-3), 8.47% (score 4), 16.28% (score 5), 6.67% (score 6), 23.08% (score 7), and 36.36% (score 8). The recurrence rate was 4.86% at a score < 5 and 16.49% at a value 5; a score cutoff 5 predicted AF recurrence with a sensitivity 64% and specificity 68%. The present analysis suggests the usefulness of CAAP-AF scoring system, with its simple and easily obtained six clinical variables, to predict AF recurrence after PVI by means of second-generation cryoballoon. A score value 5 predicted AF recurrence with a sensitivity 64% and specificity 68%.