BEST trial was published in 2015, comparing CABG and the latest technological advancement of PCI, second generation Drug-eluting stents in multivessel disease. Their results were indicative of CABG being a better option for patients with CAD. A trial published in 2021 (Fractional Flow Reserve versus Angiography for Multivessel Evaluation, FAME 3), also concluded that CABG is a safer option than PCI, when comparing results after one year from intervention. Complications
The most common complications of CABG are postoperative bleeding, heart failure, Atrial fibrillation (a form of arrhythmia), stroke, renal dysfunction, and sternal wound infections.Postoperative bleeding occurs in 2-5% of cases and might force the cardiac team to take the patient back to operating theatre to control the bleeding The most common criterion for that is the amount blood drained by chest tubes, left after the operation. Re-operation addresses surgical causes of that bleeding, which might originate from the aorta, the anastomosis or a branch of the conduit insufficiently sealed or from the sternum. Medical causes of bleeding include platelet abnormalities or coagulopathy due to bypass or the rebound heparin effect (heparin administered at the beginning of CPB reappears at blood after its neutralization by protamine).As for heart failure, low cardiac output syndrome (LCOS) can occur up to 14% of CABG cases and is according to its severity, is treated with inotropes, IABP, optimization of pre- and afterload, or correction of blood gauzes and electrolytes. The aim is to keep a systolic blood pressure above 90mmHg and cardiac index (CI) more than 2.2 L/min/m2. LCOS is often transient.
They can be done either with the clamp still on or after removing the aortic clamp and isolating a small segment of the aorta by placing a partial clamp (but atheromatic aortas might be damaged by overhandling them; atheromatic derbis might get detached and cause embolization in end organs)
Weaning from cardiopulmonary bypass and closureAfter the proximal anastomoses are done, the clamp is removed, aorta and conduits deaired, pacing wires might be placed if indicated and if the heart and other systems are functioning well CBP is discontinued,  cannulas removed and protamine is administered to reverse the effect of heparin . After possible bleeding sites are checked, chest tubes are placed and sternum is closed. Off-pump (OPCABG)
Off-pump coronary artery bypass graft (OPCABG) surgery avoids using CPB machine by stabilizing small segments of the heart. It takes great care and coordination among the surgical team and anesthesiologists to not manipulate the heart too much so hemodynamic stability will not be compromised; however, if it is compromised, it should be detected immediately and appropriate action should be taken. To keep heart beating effectively, some maneuvers can take place like placing atrial wires to protect from bradycardia, placing stitches or incisions to pericardium to help exposure. Snares and tapes are used to facilitate exposure. the aim is to avoid distal ischemia by occluding the vessel supplying distal portions of the left ventricle, so usually LIMA to LAD is the first to be anastomosed and others follow.