Causes

Causes

Heart failure can have any number of causes, or pathogeneses, but among the most common are heart attack and cardiomyopathy. A heart attack (myocardial infarction) can destroy part of the heart muscle, leaving so much tissue damaged or dead that the heart cannot function at full capacity. Cardiomyopathy, or weakening of the heart muscle, typically results from infection or disease of the heart, which leaves it unable to squeeze out enough blood with each beat.

Narrowed arteries restrict the flow of blood out of the heart, burdening the heart muscle with the task of pumping more blood through tighter passageways. Wear-and-tear on the overworked heart gradually erodes its ability to perform. Indeed, high blood pressure (hypertension) regardless of its cause most certainly contributes to heart failure: about 75 percent of heart failure patients have high blood pressure before heart failure is diagnosed, according to the American Heart Association (AHA).*

Infection or disease of the heart valves (valvular disease) and heart defects may also contribute to heart failure, but these are less common causes.

*American Heart Association. Heart Disease and Stroke Statistics — 2003 Update. Dallas, Tex.: American Heart Association; 2002.