Impact of Total Coronary Revascularization Via Left Anterior Thoracotomy (TCRAT) vs. Robotic-Assisted Harvesting of LIMA (ITcrats)

Overview

The two types of total coronary revascularization via left anterior thoracotomy (TCRAT) might have their potential benefits and disadvantages. The proposed randomized clinical trial here will compare 'RA-TCRAT' with 'Nonrobotic TCRAT' procedures concerning effects on hospital stays, overall healthcare costs, safety, and feasibility. If the two TCRAT procedures are comparably effective and safe, the 'Nonrobotic TCRAT' procedure is probably preferred as it seems easier to use. However, if the 'Nonrobotic TCRAT' procedure is less effective and less safe than the "robotic TCRAT,' that procedure should be preferred.

Rationale A recent study involving 1,195 patients from the Society of Thoracic Surgeons Registry undergoing robotic-assisted-minimally-invasive direct coronary artery bypass (RA-MIDCAB) by 114 surgeons between 2014 and 2019 showed that surgeons can quickly reduce complication rates by building up the learning curve. It is yet unclear if robotic-assisted harvesting of the left internal thoracic artery (RA-LITA) would offer a benefit over total coronary revascularization via left anterior thoracotomy (TCRAT) in terms of the postoperative hospital stay and cost of healthcare. That raises the need to examine the impact of RA-LITA compared with TCRAT on these crucial clinical outcomes. Objective The primary objective of this prospective randomized clinical trial (RCT) is, compared with TCRAT, to examine the impact of robotic-assisted coronary artery bypass graft (RA-CABG) on the length of hospital stay in diverse patients scheduled for elective surgical coronary revascularization. Secondary objectives include identifying the overall costs and charges of healthcare, operating room and intensive care unit (ICU) stays, postoperative bleeding, need for re-explorative surgery or transfusion, postoperative major adverse cardiovascular and cerebrovascular events (MACCE)\], acute kidney injury (AKI), and surgical related complications and 30-days and 3-months need for hospital re-admission and survival after adult cardiac surgical coronary revascularization using cardiopulmonary bypass (CPB). Hypothesis It is hypothesized that RA-total coronary revascularization via left anterior thoracotomy (TCRAT) might have shorter hospital stays than the nonrobotic assisted TCRAT in adult patients undergoing elective coronary revascularization surgery. Nature and extent of the burden and risks associated with participation, benefit, and group relatedness There is no expected patient burden or risk other than the estimated risks for the coronary revascularization surgery. Patient burden and risks are low, and the two surgical approaches (nonrobotic TCRAT and RA-CABG/TCRAT) are being used widely and interchangeably. The collection of patients' outcome data from hospital charts and (electronic) medical records systems causes no harm to the patients; patients will not experience any discomfort from any of the study interventions because they will be performed during general anesthesia. INTRODUCTION AND RATIONALE 3.1 TCRAT has a significant impact on outcomes. The main goals of minimally invasive cardiac surgery (MICS) are to avoid sternotomy, reduce postoperative blood product transfusion, shorten ventilation times, shorten intensive care and hospital stays, improve the quality of postoperative analgesia, and expedite physical recovery. TECRAT emerged as a promising MICS procedure. TCRAT has been shown to have a likely success rate of 95%, defined as complete revascularization in a cohort of 102 multivessel coronary artery disease (MV-CAD) patients with diverse age, body mass index (BMI), and left-ventricular ejection fraction (LVEF) in conjunction with low incidences of in-hospital mortality, CVA, AMI and need for revascularization in 2%. Muliarterial TCRAT increased the aortic cross-clamping and operating room times without further improving these outcomes or shortening hospital stays. 3.2 Robotic totally endoscopic CABG (TE-CABG) Robotic TE-CABG is technically more challenging than RA-CABG. Kofer et al. compared the 12 years of single-center experience performing conventional CABG or TE-CABG in a propensity score-matched retrospective study. They identified similar age groups, log European System for Cardiac Operative Risk Evaluation (EuroSCORE), perioperative mortality, AMI, and stroke rate, and long-term survival and freedom from major adverse cardiac and cerebral events at 1, 5, and 10 years after surgery between the two groups. TE-CABG took 40% longer CPB and 67% cross-clamp times. That doubts the superiority of TE-CABG over the RA-MIDCAB or RA-TCRAT. 3.3. RA-MIDCAB MIDCAB is performed without the use of CPB with associated fewer complications such as perioperative CVA due to avoidance of aortic manipulation. CPB might be required in rare cases during MIDCAB procedures that necessitate peripheral cannulation to avoid a sternotomy, which could be challenging in patients with severe peripheral vascular disease and morbidly obese patients who would benefit the most from avoiding a sternotomy. A RA-MIDCAB procedure may be possible in such patients. Patrick et al. demonstrated a growing learning curve after the 10th RA-MIDCAB procedure in terms of reduced rates of approach conversion (odds ratio, 0.27; 95% CI, 0.09-0.84) and improved procedural success (odds ratio, 1.96; 95% CI, 1.00-3.84). A cohort of 605 RA-MIDCAB patients performed at a single center over 18 years showed a reduced conversion rate to sternotomy for any cause, from 16.0% of the first 200 cases to 6.9% of the last 405 patients. The mortality rate was 0.3%, the patency rate of the LITA-to-left anterior descending (LAD) coronary artery anastomosis was 97.4%, surgical re-exploration for bleeding in 1.8% of patients, and the transfusion rate was 9.2%. A previous study found that compared with those who underwent conventional CABG (n=235), patients who received RA-CABG (n=281) had fewer risk factors, lower in-hospital and long-term mortality but had comparable incidences of target lesion revascularization (TLR), target vessel revascularization (TVR), AMI, and stroke. Interestingly, neither the residual Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) score nor completeness of revascularization were related to the long-term mortality. 3.4. RA-CABG: An emerged approach to improve outcomes A retrospective study demonstrated that compared with MIDCAB, RA-CABG had comparable complete revascularization, one-year graft patency, surgical conversion, mortality rates, more extended operating room stays, and shorter ICU stays. To our knowledge, no RCT compares the impacts of TCRAT and RA-TCRAT CABG on successful revascularization, mortality, and postoperative CVA and AMI. 3.5. Feasibility The two types of TCRAT (nonrobotic or R.A.) have never been compared in terms of feasibility. 'RA-TCRAT' procedures are more complex to perform and might take longer durations to be accomplished, increasing the overall healthcare costs, which could be unacceptable for both the stakeholders. 'Non-RA-TCRAT' procedures are more straightforward to perform and are thus easier to learn, but most importantly, they take much less time.