What is the most common cause of heart failure?

The most common cause of heart failure is coronary artery disease (CAD). CAD involves the narrowing or blockage of coronary arteries due to atherosclerosis, which can lead to reduced blood flow to the heart muscle. As the heart struggles to receive adequate oxygen and nutrients, it can become weakened over time, eventually resulting in heart failure.

Coronary artery disease often leads to other complications such as myocardial infarctions (heart attacks), which are significant contributors to heart failure but are typically a result of the underlying CAD. This means that while myocardial infarction is a crucial risk factor, it is usually a consequence of CAD rather than its leading cause.

In contrast, hypertension and valvular disease also play important roles in the development of heart failure. Hypertension can cause the heart to work harder, leading to left ventricular hypertrophy and eventually heart failure if not managed. Valvular disease can disrupt the normal flow of blood through the heart and contribute to heart failure. However, CAD remains the predominant underlying cause, as its prevalence and direct impact on the heart's functioning surpass that of these other conditions.