Illustration of a typical<unk> . A vein from the leg is removed and grafted to the coronary<unk>  to bypass a blockage.<unk>  during mobilization (freeing) of the right coronary<unk>  from its surrounding tissue, adipose tissue (yellow). The tube visible at the bottom is the aortic cannula (returns blood from the HLM). The tube above it (obscured by the surgeon on the right) is the venous cannula (receives blood from the body). The patient's heart is stopped and the aorta is cross-clamped. The patient's head (not seen) is at the bottom. # The patient is brought to the operating room and moved onto the operating table. # An anaesthetist places intravenous and<unk> al lines and injects an analgesic, usually fentanyl, intravenously, followed within minutes by an induction agent (usually propofol or etomidate) to render the patient unconscious. # An endotracheal tube is inserted and secured by the anaesthetist and mechanical ventilation is started. General anaesthesia is maintained with an inhaled volatile anesthetic agent such as isoflurane. # The chest is opened via a median sternotomy and the heart is examined by the surgeon. # The bypass grafts are harvested – frequent vessels are the internal thoracic<unk> es, radial<unk> es and saphenous veins. When harvesting is done, the patient is given heparin to inhibit blood clotting. # In the case of "off-pump"<unk> , the surgeon places devices to stabilize the heart. # In the case of "on-pump"<unk> , the surgeon sutures cannulae into the heart and instructs the perfusionist to start cardiopulmonary bypass (CPB) normally instructing the perfusionist to "Go on pump". Once CPB is established, there are two technical approaches: either the surgeon places the aortic cross-clamp across the aorta and instructs the perfusionist to deliver cardioplegia with a cooled potassium mixture to stop the heart and slow its metabolism or performing bypasses on beating state (on-pump beating). # One end of each vein graft is sewn on to the coronary<unk> es beyond the obstruction and the other end is attached to the aorta or one of its branches. For the internal thoracic<unk> , the<unk>  is severed and the proximal intact<unk>  is sewn to the LAD beyond the obstruction. Aside the latter classical approach, there are emerging techniques for construction of composite grafts as to avoiding connecting grafts on the ascending aorta (Un-Aortic) in view of decreasing neurologic complications. # The heart is restarted by removing the aortic cross clamp; or in "off-pump"<unk> , the stabilizing devices are removed. In cases where the aorta is partially occluded by a C-shaped clamp, the heart is restarted and suturing of the grafts to the aorta is done in this partially occluded section of the aorta while the heart is beating. # Once the grafts are completed distally and proximally, the patient is rewarmed to a normal temperature and the heart and other pressures are normal to support coming off the bypass machine, weaning off the bypass machine begins. # The perfusionist makes sure they have enough volume to come off bypass, confirms that anesthesia is ventilating the patient, confirms that vacuum assist is off (if used), and vocalizes each step in the weaning process to the surgeon and anesthesia. Volume can be given to the patient through the<unk> al line of the bypass machine while the aortic cannula is still in. # Protamine is given to reverse the effects of heparin. # Chest tubes are placed in the mediastinal and pleural space to drain blood from around the heart and lungs. # The sternum is wired together and the incisions are sutured closed. # The patient is moved to an intensive care unit (ICU) or cardiac universal bed (CUB) to recover. Nurses in the ICU monitor blood pressure, urine output, respiratory status, and chest tubes for excessive or no drainage. # After awakening and stabilizing in the ICU for 18 to 24 hours, the person is transferred to the cardiac<unk>  ward. If the patient is in a CUB, equipment and nursing is "stepped down" appropriate to the patient's progress without having to move the patient. Vital sign monitoring, remote rhythm monitoring, early ambulation with assistance, breathing exercises, pain control, blood sugar monitoring with intravenous insulin administration by protocol, and anti-platelet agents are all standards of care. # The patient without complications is discharged in four or five days. Minimally invasive technique Alternate methods of minimally invasive<unk>  have been developed. Off-pump coronary<unk>  bypass (OPCAB) is a technique of performing bypass<unk>  without the use of cardiopulmonary bypass (the heart-lung machine). Avoidance of aortic manipulation may be achieved through the "anaortic" or no-touch OPCAB technique, which has been shown to reduce stroke and mortality compared to on-pump<unk> . Further refinements to OPCAB have resulted in minimally invasive direct<unk>  (MIDCAB), a technique of performing bypass<unk>  through a 5 to 10 cm incision. Hybrid Coronary Revascualrisation, where the LIMA-to-LAD anastomosis is combined with percutaneous stents in other atherosclerotic sites, has been shown to have significant advantages compared to conventional<unk> , including a decrease in the incidence of blood transfusion, and a reduced intubation time. A 2018 meta-analysis has however demonstrated a greater financial cost when compared to conventional<unk> . Choice of source of grafts Heart bypass patient showing almost invisible residual scarring. Left: days after operation. Middle: chest scar, two years later. Right: leg scar from harvested vein, two years later. The choice of is highly dependent upon the particular surgeon and institution. Typically, the left internal thoracic<unk>  (LITA) (previously referred to as left internal mammary<unk>  or LIMA) is grafted to the left anterior descending<unk>  and a combination of other<unk> es and veins is used for other coronary<unk> es. The great saphenous vein from the leg is used approximately in 80% of all grafts for<unk> . The right internal thoracic (mammary)<unk>  (RITA or RIMA) and the radial<unk>  - RA from the forearm are frequently used as well; in the U.S., radial<unk>  and saphenous vein graft are usually harvested either endoscopically, using a technique known as endoscopic vessel harvesting (EVH), or with the open-bridging technique, employing two or three small incisions. The right gastroepiploic<unk>  from the stomach is infrequently used given the difficult mobilization from the abdomen. However, analysis published in 2015 demonstrated an angiographic superiority of RIMA and RA over SVG, while the RIMA is expected to achieve a better patency rate than the RA. Follow up * Acute - patients without complications are typically seen 3–4 weeks post operatively, at which time driving may be resumed and formal cardiac rehabilitation begun to increase aerobic endurance and muscular strength. * Chronic - * a cardiac stress test at five years is recommended, even in the absence of cardiac symptoms. * an intensive medical regimen including statins, aspirin, and aerobic exercise is essential to delaying the progression of plaque formation in both the native and grafted vessels. File:Blausen 0151<unk>  02.Illustration depicting<unk>  (double bypass) File:Blausen 0155<unk>  Single.Illustration of Single bypass File:Blausen 0153<unk>  Double.Illustration of Double bypass File:Blausen 0156<unk>  Triple.Illustration of Triple bypass File:Blausen 0154<unk>  Quadruple.Illustration of Quadruple bypass
Coronary artery bypass surgery
Bypass surgery
Totally endoscopic coronary artery bypass surgery
Cardiomyoplasty
Aortic valvuloplasty
Coronary stent
Valvulotomy
Percutaneous coronary intervention