What is the most common cause of dilated cardiomyopathy?

The most common cause of dilated cardiomyopathy is often attributed to idiopathic factors, which means the exact etiology is unknown in many cases. However, among identifiable causes, alcohol consumption is a significant contributor due to its cardiotoxic effects, which can lead to myocardial damage and ultimately result in dilated cardiomyopathy. Chronic alcohol abuse can directly affect myocardial function and structure, leading to dilation of the heart chambers.

Alcohol-induced dilated cardiomyopathy is characterized by ventricular dilation and impaired systolic function, and it can occur with prolonged heavy drinking. It is essential to recognize that the disorder can sometimes be reversible with abstinence from alcohol, highlighting the importance of identifying alcohol as a causative factor in patients presenting with symptoms of heart failure and cardiac dilation.

While myocarditis, doxorubicin toxicity, and other conditions can indeed lead to dilated cardiomyopathy, they are not as prevalent in the general population as alcohol-related cardiomyopathy. Thus, while many cases may be classified as idiopathic overall, alcohol remains a well-recognized and common mechanism when identifiable causes are considered.