A 46 year-old male with chest pain and elevated Troponin I; cath shows normal coronary arteries and an EF of 40% with global hypokinesis. Most likely diagnosis?

• A. Myocarditis
• B. Pericarditis
• C. Hypertrophic cardiomyopathy
• D. Coronary artery disease

Answer: (A)

When troponin is elevated but the coronary arteries are normal, think of non-ischemic myocardial injury rather than a heart attack. The global hypokinesis with an EF around 40% indicates the problem is diffuse across the ventricle, not limited to a single coronary territory. This pattern fits myocarditis, an inflammatory process of the heart muscle often following a viral illness, which damages myocytes, releases troponin, and can impair systolic function. Pericarditis would usually present with characteristic chest pain features and may not show such diffuse LV dysfunction; hypertrophic cardiomyopathy would show thickened walls rather than diffuse hypokinesis; coronary artery disease would typically cause regional wall motion abnormalities in a vascular distribution.