Coronary artery bypass surgery Post-Operative Complications

Associate Editors-in-Chief: ,Mohammed A. Sbeih, M.D. [mailto:msbeih@perfuse.org]

Post-operative complications
Patients undergoing coronary artery bypass grafting are at risk for the same complications as any surgery. There are also additional risks associated specifically with CABG.

CABG associated complications

 * Postperfusion syndrome (also known as "pumphead"), is a transient neurocognitive impairment associated with cardiopulmonary bypass. Some research demonstrated that the incidence is initially decreased by Off-pump coronary artery bypass, but no difference in neurocognitive function was observed beyond three months after surgery.  A neurocognitive decline over time has been demonstrated in people with coronary artery disease regardless of treatment (OPCAB, conventional CABG or medical management).  The neurocognitive decline has also been attributed to the administration of general anesthesia as part of the procedure.
 * Nonunion of the sternum; internal thoracic artery (LIMA) harvesting devascularizes the sternum and may increase the risk.
 * Myocardial infarction due to hypoperfusion, reperfusion injury, early graft occlusion due to thrombosis or technical failures at the anastomotic site, or graft failure. In the PREVENT IV study, perioperative MI was defined as a creatinine kinase-MB increase > or = 10 X the upper limit of normal or a > or = 5 X the upper limit of  normal with the development of new 30-ms Q waves within 24 hours of surgery.   Perioperative MI was observed in 9.8% of patients. Perioperative MI was associated with 1) longer surgery (250 vs 230 minutes; p <0.001), higher rates of on-pump surgery as compared with minimally invasive surgery (83% vs 78%; p = 0.048), and worse quality of target vessels (p <0.001).  Perioperative MI was associated with more frequent angiography within 30 days of the procedure (1.7% vs 0.6%; p =  0.021) as well as higher rates of SVG failure at one year (62.4% vs  43.8%, p  <0.001). Perioperative MI was associated with an increased risk of death, MI, or  revascularization at two years(19.4% vs 15.2%; p = 0.039, multivariate hazard ratio 1.33, 95% confidence  interval 1.00 to 1.76, p = 0.046) adjusting for differences in  significant predictors.
 * Late graft stenosis, particularly of saphenous vein grafts due to atherosclerosis and excessive intimal hyperplasia causing recurrent angina or myocardial infarction.
 * Acute renal failure due to hypoperfusion, embolization of debris from the aorta, and reperfusion injury. The incidence is approximately 3.6%. The mortality is approximately 20%. The length of hospitalization is prolonged from 4 days to 20 days in patients with post-operative renal failure.
 * Stroke, secondary to aortic manipulation or hypoperfusion and reperfusion injury.
 * Shunting due to SVG anastomosis into the great cardiac vein

General surgical complications

 * Infection at incision sites or sepsis. Women, obese patients, and diabetic patients are at greater risk of this complication.
 * Deep vein thrombosis (DVT)
 * Anesthetic complications such as malignant hyperthermia.
 * Keloid scarring
 * Chronic pain at incision sites
 * Chronic stress related illnesses
 * Death