Which of the following is NOT listed as a potential cause of dilated cardiomyopathy?

• A. Alcohol directly damages myocardium
• B. Beriberi
• C. Hypertrophic obstructive cardiomyopathy
• D. Chagas disease

Answer: (C)

Dilated cardiomyopathy develops when the myocardium is damaged by toxins, nutritional deficiencies, or infections, leading to chamber dilation and reduced systolic function. Alcohol directly injures heart muscle, beriberi from thiamine deficiency impairs myocardial energy use, and Chagas disease causes autoimmune and parasitic damage to the myocardium—all classic causes that produce dilation and systolic dysfunction. In contrast, hypertrophic obstructive cardiomyopathy involves thickened heart walls with dynamic obstruction of the outflow tract. This is a hypertrophic, not dilated, process, so it isn’t listed as a cause of dilated cardiomyopathy.