[Acute autoimmune myocarditis secondary to Graves' disease: a case report]

Interactions between heart and thyroid are strong. Main cardiac complications of Graves' disease are supra-ventricular tachycardia or high output cardiac failure, without real myocardial involvement.

A 40-year-old man with history of refractory Graves' disease was hospitalized for an acute chest pain with elevated cardiac biomarkers and normal coronarography. Acute myocarditis was confirmed by cardiac MRI. We found no evidence for an infectious etiology. We retained the hypothesis of acute autoimmune myocarditis in the context of active Graves' disease.

Acute myocarditis is an exceptional complication of Graves' disease, with most likely an autoimmune mechanism. Possible occurrence of fulminant rhythmic or hemodynamic complications justify minimal cardiological check-up before introducing beta blockers.