Early Atrial Tachyarrhythmia Recurrence Predicts Late Atrial Tachyarrhythmia Recurrence After the Cryo-Maze Procedure　― An Observational Study ―

BACKGROUND: It is unknown whether early atrial tachyarrhythmia (ATA) recurrence occurring within 3 months after the Maze procedure predicts late ATA recurrence. METHODS AND RESULTS: This study involved 610 patients who underwent the modified Cryo-Maze procedure in conjunction with other cardiac surgery. The primary outcomes were late ATA recurrence, defined as occurring ≥3 months after surgery. The effects of early ATA recurrence on late ATA recurrence were analyzed using a Cox proportional hazards model. The following 11 covariates were considered explanatory variables: early ATA recurrence, age, sex, body surface area, preoperative duration of atrial fibrillation, preoperative left atrial diameter, and concomitant surgery (mitral valve replacement, mitral valve repair, aortic valve replacement, tricuspid annuloplasty, and left atrial appendage closure). Statistical analyses were performed with a 2-sided 5% significance level. Early ATA recurrence occurred in 174 patients (28.5%). Late ATA recurrence occurred in 167 patients (27.5%), with 595 events identified in these patients. The Cox proportional hazards model showed that early ATA recurrence was an independent predictor of late ATA recurrence (hazard ratio, 4.14; 95% confidence interval, 3.00-5.70; P<0.001). CONCLUSIONS: Early ATA recurrence was an independent predictor of late ATA recurrence among patients undergoing the modified Cryo-Maze procedure. The blanking period might not be applied to patients undergoing the modified Cryo-Maze procedure.