Efficacy of Cox Maze IV Procedure Using Argon-Based Cryoablation: A Comparative Study with N₂O-Based Cryoablation

Abstract

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.

Randomized Trial of Concomitant Maze Procedure Using Nitrous Oxide- Versus Argon-Based Cryoablation

“…A few studies have compared the results of cryomaze procedures using the two different probes. Lee and colleagues [5] reported that the Cox maze IV procedure using an argon-based cryoprobe was safe and effective compared with the maze procedure using the N 2 O-based cryoprobe; follow-up was performed for 2 years postoperatively in this study. However, Goette and colleagues [4] reported that the argon-based device was a risk factor for failure of concomitant cryoablation (hazard ratio 2.147, p ¼ 0.018).…”

“…Persistent AF was defined as non-self-terminating AF lasting more than 7 days or less than 7 days if cardioversion was required according to Heart Rhythm Society guidelines [7]. Exclusion criteria were as follows: (1) previous cardiac surgery, (2) infective endocarditis, (3) congenital heart disease, (4) old age (>75 years), (5) left atrial size greater than 80 mm, (6) connective tissue disease such as Behcet's disease, and (7) moderate or greater tricuspid regurgitation. We created a random-allocation sequence with computer-generated 1:1 random numbers.…”

Comparison of Radiofrequency Ablation and Cryoablation for the Recovery of Atrial Contractility and Survival

“…Both radiofrequency ablation and cryoablation are known to be safe and effective for restoring sinus rhythm in AF patients [ 5 – 12 ]. The sinus rhythm restoration rate has been reported to be between 61% and 85% [ 6 – 13 ], which is slightly lower than that reported for the standard ‘cut-and-sew’ Cox maze III procedure [ 5 – 12 ]. However, it has been argued that the restoration rate of the standard Cox-maze III has been overestimated, with the real restoration rate being approximately 80% [ 13 ].…”

“…Few studies have compared the results of the maze procedure according to the energy source used [ 8 , 9 , 12 ]. In the current study, the frequency of sinus rhythm was higher in the cryoablation group, whereas that of AF was higher in the radiofrequency ablation group at discharge.…”

Application of cryoablation for the treatment of atrial fibrillation in patients undergoing cardiac surgery: Our mid-term results

“…By freezing the tissue to very cold temperatures and creating electrical obstacles, electrical activity is permanently obstructed. [3,6,7] In the present study, we aimed to present midterm results of isolated left atrial (LA) or biatrial cryoablation technique for the treatment of AF as a concomitant procedure of open cardiac surgery and to report a structured local follow-up to one year postoperatively.…”