الفهرس 
Introduction and Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
The heart is a hollow, cone-shaped muscular pump, located in the middle mediastinum. It is divided into four distinct chambers, left atrium, right atrium, left ventricle and right ventricle.
The heart chambers function in a coordinated fashion to constitute a complete heartbeat, or cardiac cycle. Heartbeats are generated in the sinoatrial (SA) node, which is the pacemaker of the heart, it generates impulses which are propagated through the conduction system (SA node, internodal pathway, A-V node, left and right bundle branches of His, and Purkinje fibers).
Cardiac ischemia results from an imbalance between myocardial O2 supply and demand. It is the myocardial consequences of the O2 supply-demand imbalance that are of central importance as they determine the clinical outcome in any given patient. Conditions increasing myocardial O2 demandinclude increase in heart rate, afterload, preload and/or contractility, necessitated by increases in physical and/or emotional activity levels. On the other hand, coronary obstruction(s) as atheroma, thrombus or embolus, altered coronary reactivity, disorders of endothelium or smooth muscle cells and extravascular compression by e.g. myocardial hypertrophy or infiltration are among the conditions limiting increase in myocardial O2 supply.
Structural abnormalities and disorders of cardiac valve function result in valvular heart disease. Etiology of valvular heart disease includes congenital, inflammatory or immunologic, endocardial disorders, myocardial dysfunction, aging and post-interventional valvular disease.
Among the congenital heart diseases commonly encountered in anesthetic practice are ventricular septal defect (VSD), tetralogy of Fallot (TOF), atrial septal defect (ASD) and patent ductus arteriosus (PDA).
Cardiac patients undergoing non-cardiac surgery require thorough preoperative assessment. Several systems have been developed to evaluate patients’ general and cardiac conditions.
Administering anesthesia to patients with preexisting cardiac disease is an interesting challenge. There is no standard rule for anesthetic management of cardiac patients, management is tailored according to the patient’s condition and the nature of the cardiac disease as well as the type and risk of planned surgery.