Reversible myocarditis after black widow spider envenomation

Area of Science:

• Toxicology
• Cardiology
• Envenomation

Background:

• Black widow spider envenomation can lead to severe clinical outcomes, but acute myocardial damage is a rarely observed complication.
• The prognostic significance of acute myocardial damage following black widow spider bites remains largely unknown.

Observation:

• A previously healthy 35-year-old man presented with systemic and cardiovascular symptoms after a black widow spider bite.
• Clinical manifestations included acute myocarditis with cardiogenic pulmonary edema, necessitating mechanical ventilation.
• Diagnostic findings revealed ST-segment elevation on ECG, elevated cardiac enzymes, left ventricular hypokinesis (ejection fraction 48%), and focal myocardial injury on MRI.

Findings:

• The patient exhibited progressive improvement in cardiac markers, biochemical parameters, and echocardiographic values (ejection fraction increased to 50%).
• This case documents a rare instance of severe cardiac involvement, including acute myocarditis and pulmonary edema, following black widow spider envenomation.
• The exact pathophysiological mechanism underlying this spider bite-induced myocarditis is yet to be elucidated.

Implications:

• Myocardial involvement following spider bites, though rare, can be life-threatening and warrants prompt recognition.
• This case underscores the potential for severe cardiovascular complications from black widow spider envenomation.
• Further research into the mechanisms of spider bite-induced myocarditis is crucial for understanding and managing these rare but serious cases.