الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 117 |  |  |
| | | from | 117 | | |
Abstract
Rheumatic heart disease is the most frequent aetiology (51.4%) of double valve lesion, followed by degenerative valve disease (40.6%). Other, less frequent cause is endocarditis. Less frequently, connective tissue disorders, aortic root and myxomatous mitral diseases .Double valve surgery accounted for 10.9% of patients undergoing valve surgery.Myocardial protection refers to strategies and techniques used during operation to prevent Ischemic reperfusion injury (IRI). These strategies help to lower heart’s metabolic demand minimizing myocardial stunning which lead to increase inotropic support and associated with fivefold increase of mortality in high risk population in open heart surgery especially double valve replacement.Cardioplegia is an essential tool for cardiac surgery. In conjunction with cardiopulmonary bypass it provides a motionless bloodless protected heart for the surgeon for double valve replacement. The ideal cardioplegia solution should provide excellent myocardial protection, cause minimal systemic electrolyte imbalance, and be effective for prolonged periods of time to minimize repeated administration. The cardioplegic solutions can be classified into two main groups. One is based on extracellular components with high potassium, magnesium and bicarbonate levels as blood cardioplegia which can be delievered at varying temperatures allowing the surgeon to customize the delivery to each patient but it must be given every 20 minutes to maintain its protective properties.