Streptococcal pharyngitis associated myocarditis (SPAM): the perfect ST-segment elevation myocardial infarction (STEMI) mimic in young individuals. A case series.

Background: The mean prevalence of ST-segment elevation myocardial infarction (STEMI) in the absence of obstructive coronary artery disease is 5-6%, while one third of these cases is attributed to myocarditis. Streptococcal pharyngitis associated myocarditis (SPAM) is a rare form of myocarditis which appears shortly after a streptococcal pharyngitis and presents as a STEMI on the surface electrocardiogram.

Methods: We present the clinical course and outcome of two young and previously healthy individuals, diagnosed with SPAM. Both of them had a positive throat culture for streptococcus with a typical ST-segment elevation myocardial infarction (STEMI) on surface electrocardiogram. The coronary angiogram was normal, while cardiac imaging tests revealed myocarditis. The patients were treated with intravenous antibiotics and made a full clinical recovery within a couple of days. Echocardiography after discharge showed no residual ventricle wall hypokinesia.

Results: Streptococcal pharyngitis associated myocarditis (SPAM) presents as STEMI on surface ECG, with recent history of streptococcal pharyngitis, evidence of myocardial injury and normal epicardial coronary arteries.

Conclusion: SPAM is an infrequent cause of myocarditis presenting as a STEMI and most commonly affects young individuals. Clinical examination and anamnesis can hint towards ongoing or recent pharyngitis whereas coronary angiography remains obligatory to exclude obstructive coronary artery disease. Positive throat culture and cardiac imaging compatible with myocarditis can confirm the diagnosis. Group A streptococcus is potentially the most frequent cause and Group B could be considered as a rare cause. Short-term prognosis appears to be favourable.