Predictors of Second Clamp Time and Conversion to Median Sternotomy in Robotic Mitral Repairs
Amy Roach, Georgina Rowe, George Gill, Dominic Emerson, Achille Peiris, Asma Hussain, Danny Ramzy, Alfredo Trento, Joanna Chikwe
Cedars-Sinai Medical Center, Los Angeles, CA, USA
BACKGROUND: There is a lack of data to guide surgeons regarding high-risk patient and operative features for repeated clamp times in robotic surgery. This study sought to identify operative and patient characteristics associated with repeated clamp time in patients undergoing robotic mitral valve repair.
METHODS: An institutional registry with prospective clinical follow-up was linked to state-wide all-hospital admissions and vital statistics databases to identify 1036 patients undergoing robotic mitral surgery between 2005-2020. Patients with history of endocarditis, significant calcifications, primary mitral replacement, prior MitraClip or without prolapse were excluded. The primary outcome was freedom from repeated clamp time or conversion to median sternotomy. Secondary outcomes included ten-year survival and freedom from >2+ mitral regurgitation or reintervention with death as a competing risk. Predictors of second clamp time or conversion to median sternotomy were identified using multivariate logistic regression.
RESULTS: The cohort consisted of 851 patients with degenerative mitral regurgitation, second clamp runs occurred in 19 patients: 15 for re-repair of residual >2+ mitral regurgitation, 3 for aortic regurgitation, and 1 for aortic dissection. The majority were repaired with 3 requiring replacement (Table 1). Conversion to sternotomy was required in three patients: one for iatrogenic aortic dissection, one for right ventricle laceration, and one for difficult visualization. The majority of patients underwent resection with band annuloplasty (67%, n=571). Additional techniques included neochordae (16.2%, n=138), chordal transfer (7.6%, n=65), and commisural suture (11%, n=94). There were 7 mitral valve replacements of the cohort, with a repair rate of 99.2%. Incidence of in-hospital or 30-day mortality was 0.4% (n=4). Survival at 10 years was 90% (95% confidence interval (CI) 85.8-92.7). Freedom from >2+ mitral regurgitation or reintervention with death as a competing risk was 88.5% (95% CI 82.6-93.1) at 10 years. In multivariate logistic regression, main predictors of second clamp time or conversion were presence of anterior or bileaflet prolapse (odds ratio 2.8 , 95% CI 1.1-6.8).
CONCLUSIONS: A near 100% repair rate may be achieved using a robotic approach, however, anterior or bileaflet prolapse increases risk for second clamp time which may have implications for patient selection early in the learning curve. 