Cryoballoon versus radiofrequency catheter ablation of paroxysmal atrial fibrillation: Biomarkers of myocardial injury, recurrence rates, and pulmonary vein reconnection patterns

BACKGROUND Cryoballoon ablation has emerged as a novel treatment strategy for patients with atrial fibrillation (AF). OBJECTIVE The purpose of this study was to compare pulmonary vein isolation (PVI) using cryoballoon ablation versus RF ablation with regard to myocardial injury, pulmonary vein (PV) reconnection patterns, and outcome. METHODS Fifty patients (age 59 +/- 9 years, ejection fraction 0.59 +/- 0.06, left atrial size 41 +/- 5 mm) with paroxysmal AF were studied. Twenty-five patients underwent PVI using a 28-mm cryoballoon. A control group of 25 patients underwent PVI using an open-irrigation RF ablation catheter. Myocardial injury was determined by measuring troponin T (TnT). PV reconnection patterns were studied in case of repeat procedures. RESULTS Procedure duration was 166 +/- 32 minutes in the cryoballoon group versus 197 +/- 52 minutes in the RF group (P = .014), with similar ablation times (cryoballoon: 45 minutes [interquartile range 40-52.5 minutes]; RF: 47 minutes [interquartile range 44-65 minutes], P = .17). Postprocedural TnT in the RF group was 1.29 +/- 0.41 mu g/L versus 0.76 +/- 0.55 mu g/L in the cryoballoon group (P = .002). In 12 patients who underwent repeat ablation, 74% of PV reconnection sites were inferiorly located in the cryoballoon group compared to 17% in the RF group (P = .0004). With 1.2 +/- 0.4 and 1.3 +/- 0.6 procedures per patient, 88% of patients in the cryoballoon group and 92% in the RF group were in stable sinus rhythm after follow-up of 12 +/- 3 months (P = NS). CONCLUSION Differences in the extent of myocardial injury and patterns of PV reconnection were observed between cryoballoon ablation and RF ablation of paroxysmal AF.