Beating-Heart Coronary Artery Bypass grafting (BH-CABG) in patients with End-Stage Renal Disease (ESRD): comparison of the Society of Thoracic Surgeons (STS) predicted risk with actual outcomes

Background End-Stage Renal Disease (ESRD) is an independent risk factor in outcomes for traditional coronary artery bypass grafting (TRAD-CAB) utilizing aortic cross-clamping and cardioplegic arrest. In order to determine if Beating-Heart CABG (BH-CABG) techniques offer benefit in patients with ESRD, an analysis of the Society of Thoracic Surgeons (STS) predicted risk versus the actual outcomes was performed. Methods Between March 2017 - October 2023, all ESRD patients underwent BH-CABG by a single surgeon at a single institution. Patients were kept normothermic, ventilation was maintained, and intra-coronary shunts with flow-probe graft assessment were utilized during the procedure. The STS predicted risk calculator was used to compare outcomes with actual results. Results There were 55 patients- 37 men and 18 women with a mean age of 61.5 years (41-77 years). Co-medical conditions consisted of the following: HTN (100%), DM (85%), Pulmonary HTN (49%), PVD (45%), CVD with CVA (18%), and COPD (9%). Fifty-one patients underwent Pump-Assisted Direct Coronary Artery Bypass Grafting (PADCAB) and four underwent Off-Pump CABG (OP-CAB). There were 16 Elective, 35 Urgent, and 4 Emergent cases. Case presentation included: 24 NSTEMI, 4 STEMI, 6 Unstable Angina, 7 CHF, 1 Cardiac Arrest, and 13 with a positive exercise stress test (EST) for renal transplant screening. The mean EF was 47% (range: 15-75%). The mean number of grafts was 2.4 (1-4) and CPB time was 78 min (34-128 min) for the PAD-CAB group. Nine of the thirteen patients (69%) listed for kidney transplant underwent the transplant, one of whom was a combined liver-kidney. There was 1 hospital mortality (1.8%) compared to a predicted 6.2%. There was 1 stroke (1.8%) compared to a predicted 3.3%. There was 1 prolonged ventilation (1.8%) compared to a predicted 20.2%. There were no return to OR and no sternal wound infections. Prolonged Lengths of Stay occurred in 3 patients (5.5%) compared to a predicted 16.9%. One-year mortality occurred in 8 patients (14.5%). The observed-to-expected outcomes was < 1 in all categories. Conclusions The BH-CABG appears to demonstrate superior outcomes compared to the STS predicted risk for CABG. The Beating-Heart technique may offer advantages by avoidance of aortic cross-clamping and cardioplegia, maintenance of normothermia and ventilation, as well as preservation of coronary blood flow during construction of bypass grafting.