A 45-year-old patient was diagnosed with an anterior myocardial infarction. The patient asks the ...

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When decreased myocardial blood perfusion is extensive or perfusion is completely blocked, the tissue becomes necrotic and a myocardial infarction occurs. Angina or angina pectoris is the result of decreased blood flow to the myocardium as a result of coronary artery spasms or temporary constriction. When stenosis occurs in the aortic and pulmonic valves, the adjacent ventricles work harder to move the ventricular volume beyond the stenotic valve. When regurgitation occurs, there is a backflow of blood into an adjacent chamber, which causes either pulmonary or systemic congestion. A dysrhythmia is a disturbance in the electrical impulse of the heart rhythm. Any rhythm not generated at the sinoatrial node is classified as such. Dysrhythmias are primary conduction disturbances that occur as a response to ischemia, valvular abnormalities, anxiety, and drug toxicity (e.g., digoxin toxicity).