Acute biopsy-proven lymphocytic myocarditis mimicking Takotsubo cardiomyopathy.

Endomyocardial biopsy (EMB), the diagnostic gold standard for myocarditis, has not been systematically performed in the reported case series of Takotsubo cardiomyopathy, although proposed Mayo Criteria specify exclusion of myocarditis. Moreover, there is no specific recommendation for infarct-like acute myocarditis in the recently published guidelines on the role of EMB. Here we present a thoroughly documented case fulfilling both the proposed Mayo criteria for Takotsubo cardiomyopathy and the World Health Organization criteria for active, virus-negative, immune-mediated myocarditis. Since myocarditis can mimic acute myocardial infarction with normal coronary arteries, EMB should be performed to rule out myocarditis in patients presenting with LV apical ballooning syndrome (or Takotsubo cardiomyopathy).