Dong Seop Jeong1, Kiick Sung1, Wook Sung Kim1, Carriere Keumhee Cho1, Pyo Won Park2. 1. Departments of Thoracic and Cardiovascular Surgery and Statistics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. 2. Departments of Thoracic and Cardiovascular Surgery and Statistics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. Electronic address: pyowonpark@gmail.com.
Abstract
BACKGROUND: Currently, two types of cryoprobes are available: nitrous oxide (N2O)-based and argon gas-based. However, few studies have compared the outcomes obtained with these two cryoprobe types. The aim of this study was to compare the early outcomes of a concomitant maze procedure using N2O-based cryoablation (the N2O group) versus argon gas-based cryoablation (the argon group) in patients with persistent atrial fibrillation (AF). METHODS: This study was a single-center, prospective, randomized controlled clinical trial. Sixty patients were randomly assigned to receive a concomitant maze procedure using N2O-based cryoablation (n = 30) or argon gas-based cryoablation (n = 30) for persistent AF. Patients were followed up at 3, 6, and 12 months by electrocardiography, 24-hour Holter monitoring, and transthoracic echocardiography. RESULTS: No important intergroup differences were observed in terms of preoperative variables, morbidity, or mortality. During 1 year of follow-up, normal sinus rhythm was maintained in 26 patients in the N2O group and 26 patients in the argon group (86.7% versus 86.7%, p = 1.000). Freedom from atrial arrhythmia events at 12 months was observed in 84.5% ± 4.7% without intergroup differences. Early AF episode before discharge was correlated with atrial arrhythmia events during follow-up (hazard ratio 7.89, 95% confidence interval: 1.75 to 35, p = 0.007). The N2O group showed earlier recovery of left atrial activity compared with the argon group (p = 0.043); however, this difference disappeared after 6 months. CONCLUSIONS: Both procedures have similar 1-year sinus rhythm maintenance rates. Left atrial contractile activity tends to return earlier in the N2O group.
RCT Entities:
BACKGROUND: Currently, two types of cryoprobes are available: nitrous oxide (N2O)-based and argon gas-based. However, few studies have compared the outcomes obtained with these two cryoprobe types. The aim of this study was to compare the early outcomes of a concomitant maze procedure using N2O-based cryoablation (the N2O group) versus argon gas-based cryoablation (the argon group) in patients with persistent atrial fibrillation (AF). METHODS: This study was a single-center, prospective, randomized controlled clinical trial. Sixty patients were randomly assigned to receive a concomitant maze procedure using N2O-based cryoablation (n = 30) or argon gas-based cryoablation (n = 30) for persistent AF. Patients were followed up at 3, 6, and 12 months by electrocardiography, 24-hour Holter monitoring, and transthoracic echocardiography. RESULTS: No important intergroup differences were observed in terms of preoperative variables, morbidity, or mortality. During 1 year of follow-up, normal sinus rhythm was maintained in 26 patients in the N2O group and 26 patients in the argon group (86.7% versus 86.7%, p = 1.000). Freedom from atrial arrhythmia events at 12 months was observed in 84.5% ± 4.7% without intergroup differences. Early AF episode before discharge was correlated with atrial arrhythmia events during follow-up (hazard ratio 7.89, 95% confidence interval: 1.75 to 35, p = 0.007). The N2O group showed earlier recovery of left atrial activity compared with the argon group (p = 0.043); however, this difference disappeared after 6 months. CONCLUSIONS: Both procedures have similar 1-year sinus rhythm maintenance rates. Left atrial contractile activity tends to return earlier in the N2O group.