Venom-induced myocarditis: An unusual case attributable to Vipera aspis bite

Abstract

Venomous bites are medical emergencies that may result in life-threatening clinical effects. Cardiovascular complications are uncommon but they can be dangerous if not early detected and treated. Cerebral and myocardial infarction are described; myocarditis as consequence of viper envenomation in humans are very rare, almost anedoctal. We present the case of a 33-year-old man, working as keeper in a reptile zoo, who arrived after a viper bite of the Vipera aspis species, on the left wrist. The patient presented with clouded sensorium, edema of the lips and tongue, rapidly worsened with angioedema, and the need for oro-tracheal intubation; severe thrombocytopenia and anemia were treated with transfusions of platelet, plasma and red blood cells. The left hand and arm worsened, with compartment syndrome, treated with surgical fasciotomy. From a cardiological point of view, the patient presented a sudden drop in blood pressure, electrocardiographic anterior and infero-lateral ST depression, pericardial effusion and hypokinesia of the interventricular septum on echocardiography, and a significant increase in troponin T. Cardiac magnetic resonance imaging confirmed the myocarditis, with the presence of septal and anterior intramyocardial edema in T2 weighted sequences, with prolonged T2 time at T2 mapping analysis, without late gadolinium enhancement areas. Cardiological and general clinical conditions gradually improved only after the antivenom was administred. This is one of the rare cases of viper bite myocarditis with echocardiographic and magnetic resonance imaging documentation in Europe; it emphasizes the importance of identifying uncommon complications of venomous snake-bites and the prompt administration of antivenom, even though snake bites are less frequent at our latitudes.