Clipless robotic LIMA harvesting: monitoring performance and safety through CUSUM and RA-CUSUM analyses

The left internal mammary artery (LIMA) remains the conduit of choice for coronary artery bypass grafting (CABG). Robotic harvesting has become a growing frontier in cardiac surgical innovation, and therefore optimizing and simplifying the technique is of significant surgical importance. In this study, we present our experience with a clipless robotic LIMA harvesting strategy (cl-LIMA), performed using robotic bipolar diathermy, followed by a hand-sewn anastomosis to the left anterior descending artery (LAD) through a Minimally Invasive Direct Coronary Artery Bypass approach (R-MIDCAB).

Fifty-seven patients underwent the R-MIDCAB procedure at the SS. Annunziata Hospital in Chieti between May 2024 and November 2025, performed by a single primary surgeon using cl-LIMA technique. Console operating times were evaluated using cumulative sum (CUSUM) analysis. A risk-adjusted CUSUM (RA-CUSUM) model was then constructed, incorporating postoperative complications that were more frequent, clinically significant, and directly influenced by operator performance.

After reaching its peak around the early cases, the CUSUM curve showed a steady and uninterrupted downward trajectory. None of the major complications (death within 30 days, major cerebrovascular events, or perioperative myocardial infarctions) occurred. The RA-CUSUM analysis showed no signs of deterioration in performance throughout the entire study period.

Robotic harvesting using cl-LIMA technique has been proposed to simplify LIMA take down. In fact, cl-LIMA technique promoted the learning process and did not emerge to be associated with a worsening of the clinical outcome with regards to the most expected complications. Additional data are needed to confirm its safety and efficacy.