Acute nonrheumatic streptococcal myocarditis: STEMI mimic in young adults.
BACKGROUND
Mimicking ST-segment elevation myocardial infarction upon presentation, acute nonrheumatic streptococcal myocarditis is a treatable etiology of myocarditis which has only been infrequently reported.


METHODS
Patients were identified through a retrospective query of electronic medical records over a 17-year period (January 1994 to December 2010). We describe a case series of acute nonrheumatic streptococcal myocarditis complicating pharyngitis in young adults.


RESULTS
Nine patients were identified; 89% were male, patients had an average age of 28.6 years, and 56% and 22% had confirmed group A and group G streptococcus, respectively. Latency from pharyngitis to chest pain averaged 3.1±1.1 days. No patients met the revised Jones criteria for acute rheumatic fever. All 9 patients (100%) presented with ST-segment elevations on electrocardiography and elevated cardiac biomarkers. Average peak creatine kinase was 934 U/L (normal<400 U/L), creatine kinase-MB was 82 ng/mL (normal<6.9 ng/mL), and troponin T was 2.30 ng/mL (normal<0.03 ng/mL). Six patients underwent coronary angiography, which revealed no obstructive culprit lesions. Cardiac magnetic resonance imaging confirmed myocarditis in 3 patients and was used to document resolution in follow-up for 2 patients. All patients had a complete clinical recovery.


CONCLUSIONS
Acute nonrheumatic streptococcal myocarditis is an under-recognized and treatable cause of ST-segment elevation and chest pain in young adults with a history of recent pharyngitis. Etiopathology extends beyond Lancefield group A streptococcus and includes group G streptococcal infection. Cardiac magnetic resonance may be useful in confirming the diagnosis and documenting the resolution.
Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA. gaupadhyay@partners.org
Gaurav A
GA
Upadhyay
Justin F
JF
Gainor
Luisa M
LM
Stamm
Arnold N
AN
Weinberg
G William
GW
Dec
Jeremy N
JN
Ruskin
D000328:Adult; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000209:etiology; D017023:Coronary Angiography; D003402:Creatine Kinase / Q000097:blood; D003937:Diagnosis, Differential; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D009203:Myocardial Infarction / Q000175:diagnosis; D009205:Myocarditis / Q000175:diagnosis* / Q000382:microbiology*; D010612:Pharyngitis / Q000209:etiology; D012189:Retrospective Studies; D013290:Streptococcal Infections / Q000175:diagnosis*; D013297:Streptococcus pyogenes; D020107:Troponin T / Q000097:blood; D055815:Young Adult
D015415:Biomarkers; D020107:Troponin T; D003402:Creatine Kinase