cardiovascular disorders
Angina Pectoris
Etiology of Angina Pectoris
Angina pectoris occurs when Cardiac workload and resultant myocardial oxygen demand exceed the ability of coronary arteries to supply an adequate amount of oxygenated blood Such imbalance between supply and demand can occur when the arteries are narrowed. Narrowing usually results from Coronary artery Atherosclerosis None Narrowing of the coronary arteries can also result from Variant Angina None Coronary artery embolism (rare) Acute coronary thrombosis can cause angina if obstruction is partial or transient, but it usually causes Acute Myocardial Infarction (MI) (MI). Because myocardial oxygen demand is determined mainly by heart rate, systolic wall tension, and contractility, narrowing of a coronary artery typically results in angina that occurs during exertion and is relieved by rest. In addition to exertion, cardiac workload can be increased by disorders such as Hypertension , A decreased oxygen supply, as in severe anemia or hypoxia, can precipitate or aggravate angina. 