Hydrocarbon Exposure in Myocarditis: Rare Toxic Cause or Trigger? Insights from a Biopsy-Proven Fulminant Viral Case and a Systematic Literature Review.

Toxic myocarditis (TM) is rare, and no systematic evidence is available regarding its treatment or prognosis. Hydrocarbons even more rarely cause TM, and they are associated with severe extracardiac toxicity. Moreover, a pathogenic interaction between viral and toxic agents in TM has not been studied. We present the first case of biopsy-proven parvovirus B19 (B19V) viral fulminant myocarditis diagnosed after hydrocarbon exposure, along with a systematic literature review of hydrocarbon-TM cases. A systematic literature review was conducted by searching hydrocarbon-TM cases. Clinical and prognostic data were recorded. After screening of 937 records, 7 were included. All cases were male, with a median age of 24 years (IQR 23-25). Chest pain and dyspnea were the main symptoms, but arrhythmic presentation was also reported; endomyocardial biopsy (EMB) was performed in only one case. Overall, treatment was based on supportive measures, such as antiarrhythmic and/or vasoactive therapy. Our example (male, 47 years old) is the first reported fulminant biopsy-proven case diagnosed after a massive exposure to hydrocarbons, in which EMB molecular analysis unexpectedly revealed B19V with a high viral load. Hemodynamic and arrhythmic instability required percutaneous stellate ganglion blockade and temporary wearable defibrillator use. Left ventricular function spontaneously normalized at 3 months. In conclusion, we report the first fulminant B19V myocarditis case temporally associated with aromatic hydrocarbon exposure due to a coexistence of viral and toxic causes. Our case and the systematic review show that promptly performing EMB can provide a definitive diagnosis and guide treatment, especially in severe cases in which infectious agents may contribute to myocardial damage.