No abstract

Reopening of occluded RGEA conduits occurred early and midterm postoperatively. Reopening appeared related to recovery from graft spasm, and could occur as late as midterm if associated with progression of native coronary artery disease.

BackgroundWe compared the mid-term results of the Cox maze IV procedure using argon-based cryoablation with a procedure using N2O-based cryoablation.MethodsFrom May 2006 to June 2012, 138 patients (mean age, 58.2±11.0 years) underwent the Cox maze IV procedure. Eighty-five patients underwent the maze procedure using an N2O-based cryoprobe (group N), and 53 patients underwent the maze procedure using an argon-based cryoprobe (group A). Bipolar radiofrequency ablation was concomitantly used in 131 patients. The presence of atrial fibrillation immediately, 6 months, 1 year, and 2 years after surgery was compared.ResultsEarly mortality occurred in 6 patients (4.3%). There were no differences in early mortality or postoperative complications between the two groups. Nineteen of 115 patients (16.5%) remained in atrial fibrillation at postoperative 12 months (14 of 80 patients (17.5%) in group N and 5 of 35 patients (14.3%) in group A, p=0.669). There were no differences in the number of patients who remained in atrial fibrillation at any of the time periods except in the immediate postoperative period. A multivariable analysis revealed that the energy source of cryoablation was not associated with the presence of atrial fibrillation at 1 year (p=0.862) and that a fine F wave (<0.1 mV) was the only risk factor predicting the presence of atrial fibrillation at 1 year (p<0.001, odds ratio=20.287).ConclusionThe Cox maze IV procedure using an argon-based cryoprobe was safe and effective compared with the maze procedure using an N2O-based cryoprobe in terms of operative outcomes and the restoration of sinus rhythm for up to 2 years after surgery.