A 29-year-old previously healthy male presented to an outside hospital emergency department with two days of flu-like symptoms including fever, chills, nausea, vomiting, abdominal pain, and recurrent episodes of syncope. On arrival, physical exam revealed a heart rate of 50 beats/minute and a blood pressure of 75/53 mmHg, elevated JVP, diminished right basilar lung sounds, hepatomegaly, and mild RUQ tenderness. Laboratory studies were notable for the following: neutrophilic leukocytosis, Na 126 mmol/L, Cr 2.0 mg/dL, AST 3,789 U/L, ALT 2,890 U/L, INR 1.7, CRP 2 mg/dL, lactate 10.8 mmol/L, CK 860 U/L, BNP 23,550 pg/mL, and Troponin I > 40 ng/mL. EKG revealed complete atrial ventricular dissociation with ventricular escape rhythm at a rate of 52 beats/minute with left bundle branch morphology and a QRS interval of 178 ms. Initially, a CT chest/abdomen/pelvis with contrast revealed constellation of findings consistent with right heart failure including congestion of the liver, right pleural effusion, ascites, body wall edema, and right atrial enlargement. The patient was then transferred to our facility for a higher level of care. An emergent transthoracic echocardiogram revealed severely reduced biventricular systolic function with an ejection fraction (EF) of <20%, and moderate biventricular dilation with severe global hypokinesis. Patient was taken to the cardiac catheterization lab, where a transvenous pacemaker was inserted. Coronary angiogram demonstrated no evidence of coronary artery disease, and right heart catheterization was consistent with cardiogenic shock with severe right ventricular failure. Severe lymphocytic myocarditis with extensive myocyte necrosis was confirmed by endomyocardial biopsy. The patient continued to deteriorate over the next 12 hours despite treatment with multiple vasopressors and CRRT. Therefore, he was placed on ECMO and transferred to a tertiary heart transplant center, where he is considered for heart transplant or mechanical circulatory support as a bridge to recovery.
Discussion:
Myocarditis is an inflammatory disease of the myocardium resulting from infectious, immune, and toxic etiology. Common initial presentations include recent-onset heart failure, arrhythmia, and chest pain. It rarely presents with high grade atrioventricular block, and has not been reported with complete atrioventricular block. This is a novel case of viral fulminant lymphocytic myocarditis presenting with both heart failure and complete heart block. The patient’s fulminant course is hypothesized to be augmented by immune-mediated response. Definitive diagnosis can only be made with endomyocardial biopsy demonstrating myocyte necrosis. A diagnosis of acute lymphocytic myocarditis should be considered in the differential for an otherwise healthy patient presenting with these findings. Potential therapies to consider following diagnosis include: supportive therapy with mechanical circulatory support device and evidence-based heart failure therapy. Immunosuppression with high dose steroids should be considered but is controversial.
Conclusions:
A diagnosis of acute lymphocytic myocarditis should be considered in the differential for a patient presenting with complete atrioventricular block and multi-organ failure.