The impact of incomplete revascularization on survival in minimal invasive off-pump coronary artery surgery: a propensity score analysis of 1,149 cases.

Background: Minimally invasive concepts are increasingly influential in modern cardiac surgery. This study aimed to evaluate the effect of completeness of revascularization on clinical outcomes and overall survival in minimally invasive, thoracoscopic coronary artery bypass grafting (CABG) surgery. Methods: We retrospectively evaluated a consecutive series of 1,149 patients who underwent minimally invasive off-pump CABG with single, double, or triple-vessel revascularization between 2007 and 2018. Of these patients, 185 (16.1%) had incomplete revascularization (IR) (group I), and 964 (83.9%) had complete revascularization (CR) (group C). We used gradient boosted propensity score estimation to account for possible confounding variables. Results: Median age was 69 years, interquartile range (IQR) 60-76 years, and median EuroSCORE II was 4, IQR 2-7. Of the 1,149 patients, 495 patients suffered from two vessel disease (VD) and 353 presented with three VD. Long-term median follow-up 5.58 (3.27-8.48) years was available for 1,089 patients (94.8%). The incidence of recurrent or persisting angina, myocardial infarction, redo-bypass surgery, and stroke during follow-up did not differ significantly between groups. During follow-up, there were 47 deaths in group I and 172 deaths in group C. The 1-, 3-, 5-, 8-, and 10-year unadjusted survival rates were 94%, 84%, 75%, 62%, and 51% for group I, and 97%, 94%, 88%, 77%, and 72% for group C, respectively (long-rank test P<0.001), favouring CR. Following risk adjustment the long-rank test P value for survival was 0.23. Conclusions: In minimally invasive coronary surgery, IR resulted in decreased long-term survival, but did not achieve statistical significance after risk adjustment. However, IR should only be used in carefully selected cases.