Single Center Prospective Study of Cross-Clamp versus Balloon Occlusion in Robotic Mitral Surgery

BACKGROUND Both transthoracic aortic cross-clamp and endoaortic balloon occlusion have been shown to have comparable safety profiles for aortic occlusion. Since most surgeons use only one technique, we sought to compare the outcomes when a homogeneous group of surgeons changed their occlusion technique from aortic cross-clamp to balloon occlusion. METHODS We changed our technique from aortic cross-clamp to balloon occlusion in November 2022. This allowed us to conduct a prospective treatment comparison study in the same group of surgeons. Propensity score matching (PSM) was used to match cases(balloon occlusion) 1:3 to controls (aortic cross-clamp) based on age, gender, body mass index, concomitant maze, and tricuspid valve repair. RESULTS Total of 411 patients underwent robotic mitral surgery from 2020 through 2023. Using PSM, 56 balloon occlusion patients were matched to 168 aortic cross-clamp patients. Median age was 65 years (interquartile range[IQR],55.6-70.0) and the majority were males(n=119,53%). All valves were successfully repaired. Balloon occlusion had a shorter median cardiopulmonary bypass (CPB) time compared to aortic cross-clamp (84.0 vs. 94.5 min,p=0.006). Median cross-clamp time (64.0 vs. 64.0 min,p=0.483) and total surgery time (5.9 vs. 6.1 hours,p=0.495) did not differ between groups. There was no in hospital death. There were five surgeons who performed various combinations of console and bedside roles. CPB, cross-clamp, and surgery durations were not significantly affected by the different surgeon combinations. CONCLUSIONS Compared to aortic cross-clamp, balloon occlusion has similar perioperative and early postoperative outcomes. Additionally, it likely introduces a 10-minute reduction in total CPB time.