Single-Center Success of Concomitant Cryothermal Cox-Maze IV Procedure

Background. Despite the guideline recommendation, implementation of the Cox-maze (CM) IV procedure has been variable and current data are limited. Methods. We reviewed patients with concomitant CM IV procedure (05/2019-05/2020). The primary endpoints of the study were the success rate of surgical ablation and continuity of sinus rhythm (SR) 1 year after surgery. Secondary endpoints included permanent pacemaker (PPM) implantation, postoperative mortality, and identification of predictors for postoperative SR. Results. The concomitant CM IV procedure was performed in 92 patients. Indications were persistent atrial fibrillation (AF) in 40 patients (43.5%), paroxysmal AF in 36 (39.1%), and long-standing persistent AF in 16 (17.4%). At hospital discharge, SR was achieved in 49 patients (63.6%) and PPM implantation was necessary in 12 patients (13%). At 1 year after surgical ablation, SR was seen in 31 patients (59.6%) and PPM implantation was required in six further patients (6.5%). Patients with long-standing persistent AF were significantly less likely to achieve SR (odds ratio (OR): 0.18, p=0.003), and postoperative mortality was significantly increased in this subgroup (hazard ratio (HR): 5.4, p=0.02). In patients with enlarged left atrial (LA) diameter, the probability of achieving SR was significantly decreased (OR: 0.48, p=0.045). Need for postoperative dialysis (HR: 12.9, p=0.02) and prolonged stay in the intensive care unit (HR: 2.2, p=0.01) were independently associated with increased mortality after CM IV. Conclusions. The cryothermal CM IV procedure has an overall 1-year success rate of 60% with increased rates of PPM implantation. Patients with long-standing persistent AF and increased LA diameter were significantly less likely to achieve SR.