RT Book, Section A1 Jahania, M. Salik A1 Gottlieb, Roberta A. A1 Mentzer, Jr., Robert M. A2 Cohn, Lawrence H. A2 Adams, David H. SR Print(0) ID 1144151365 T1 Myocardial Protection T2 Cardiac Surgery in the Adult, 5e YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9780071844871 LK accesssurgery.mhmedical.com/content.aspx?aid=1144151365 RD 2024/03/19 AB Myocardial protection in the operating room refers to strategies and methods used to attenuate or prevent perioperative infarction and/or postischemic ventricular dysfunction. In the setting of an acute myocardial infarction (MI) it refers to adjuvant therapy administered before, during or after reperfusion therapy. In transplantation it refers to the methods used to preserve the donor heart. Although the clinical situations are different, the goal of protection is the same, that is, to prevent or treat myocardial stunning and infarction. The underlying pathophysiology in all three settings is the same and relates to the etiology and consequences of ischemia/reperfusion (I/R) injury. After surgery the injury may manifest as low cardiac output, hypotension, and the need for postoperative inotropic support and ultimately mechanical circulatory support. I/R injury may be reversible (stunning) or irreversible (infarction) and is differentiated by electrocardiographic abnormalities (presence of a new Q-wave), elevations in the levels of specific plasma enzymes or proteins such as creatine kinase-MB and troponin I or T and/or the presence of regional or global echocardiographic wall motion abnormalities. Depending upon the criteria used, the incidence of postoperative MI in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) ranges between 3% and 18%.1-4 While the majority of these are non-Q wave infarctions, they still are independently associated with adverse outcomes and prolonged aortic cross-clamp time and duration of CPB. Despite advances in techniques and cardioprotective strategies, the incidence of severe ventricular dysfunction, heart failure and death postoperatively ranges between 1% and 15%. The higher mortality rates are generally associated with high-risk patients with minimal cardiac reserve. These complications have an enormous impact on both families and society. From an economic standpoint alone, procedures for cardiovascular diseases are costly.