Ischemic Heart Disease
Angina pectoris is a clinical syndrome of chest discomfort caused by reversible myocardial ischemia that produces disturbances in myocardial function without causing myocardial necrosis. Myocardial ischemia occurs secondary to increased myocardial demand and/or decreased myocardial oxygen supply. The specific causes of increased demand and decreased supply will be discussed. Myocardial ischemia causes several syndromes referred to collectively as ischemic heart disease including: stable angina, variant or Prinzmetal's angina, silent myocardial ischemia, and unstable angina.
-->Myocardial Oxygen Supply and Demand
Myocardial ischemia is caused by an imbalance between coronary blood flow (supply) and the metabolic needs of the myocardium (demand). Myocardial ischemia occurs when myocardial oxygen demand exceeds myocardial oxygen supply.
The major determinants of myocardial oxygen demand are heart rate, contractility, and left ventricular systolic wall tension of the three determinants, heart rate is the easiest to assess clinically with current drug therapies. Myocardial contractility refers to the rate of rise in the intraventricular pressure during isovolumetric contraction and is influenced by a number of variables including: the autonomic nervous system, heart rate, blood calcium concentration, and body temperature.
-->Signs and Symptoms
Patients with stable angina are often classified as having mainly fixed-threshold angina or mainly variable-threshold angina. Anginal syndromes in patients with fixed-threshold angina or exertional angina are precipitated by increased myocardial oxygen demand and tend to occur at some reproducible level of myocardial work. This type of angina is caused by increased myocardial oxygen demand, associated with a fixed-obstruction of an epicardial coronary artery by an atherosclerotic plaque.
Treatment
Coronary Risk Factor Reduction
Hypertension Management
Smoking Cessation
Cardiac Rehabilitation
Dyslipidemia Management
Angiotensin-Converting Enzyme Inhibitor Therapy
Antiplatelet Therapy
-->Myocardial Oxygen Supply and Demand
Myocardial ischemia is caused by an imbalance between coronary blood flow (supply) and the metabolic needs of the myocardium (demand). Myocardial ischemia occurs when myocardial oxygen demand exceeds myocardial oxygen supply.
The major determinants of myocardial oxygen demand are heart rate, contractility, and left ventricular systolic wall tension of the three determinants, heart rate is the easiest to assess clinically with current drug therapies. Myocardial contractility refers to the rate of rise in the intraventricular pressure during isovolumetric contraction and is influenced by a number of variables including: the autonomic nervous system, heart rate, blood calcium concentration, and body temperature.
-->Signs and Symptoms
Patients with stable angina are often classified as having mainly fixed-threshold angina or mainly variable-threshold angina. Anginal syndromes in patients with fixed-threshold angina or exertional angina are precipitated by increased myocardial oxygen demand and tend to occur at some reproducible level of myocardial work. This type of angina is caused by increased myocardial oxygen demand, associated with a fixed-obstruction of an epicardial coronary artery by an atherosclerotic plaque.
Treatment
Coronary Risk Factor Reduction
Hypertension Management
Smoking Cessation
Cardiac Rehabilitation
Dyslipidemia Management
Angiotensin-Converting Enzyme Inhibitor Therapy
Antiplatelet Therapy
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