Viral infections are the leading cause of myocarditis. These viral infections include influenza, adenoviruses, enteroviruses, HIV, hepatitis C, cytomegalovirus, varicella, and SARS-CoV-2.1 As virus cases rise this time of year, clinicians must be alert to symptoms of myocarditis and prepared to perform a full workup. Unfortunately, these symptoms can be vague and easily missed. If myocarditis is incorrectly diagnosed, a stable patient with mild symptoms can quickly progress to cardiogenic shock as the myocardium becomes more inflamed. Myocarditis should be suspected in patients with complaints of chest pain with electrocardiogram (ECG) changes, elevated cardiac markers, and lactic acidosis. 

Patients presenting with myocarditis typically complain of chest pain with myalgia, fever, and other typical viral-like symptoms.1 Dyspnea, fatigue, palpitations, and syncope are also common.1 Patients may have had viral symptoms for a week before presenting to the office. Take the time to evaluate the heart for any ECG changes and perform a thorough physical examination. Consider myocarditis in patients with acute ECG changes such as ST elevation indicating pericarditis.2,3

Although pericarditis is easy to treat with nonsteroidal anti-inflammatory drugs (NSAIDs) and rest, providers should still monitor for myocarditis by checking cardiac enzymes to see if any changes in troponin levels and creatinine kinase-MB are indicative of myocardium tissue damage.2 Lactate levels will be elevated in myocarditis because of muscle damage to the heart and poor perfusion.4 Do not immediately consider the elevated lactate levels as an indicator of sepsis if no other signs of infection are present.

Continue Reading

The diagnosis of myocarditis can be confirmed with endomyocardial biopsy.1 Cardiac magnetic resonance imaging (MRI) is the noninvasive gold standard method for diagnosis.1

In summary, if a patient with a current or recent viral infection has any ECG changes or other cardiac symptoms, rule out the possibility of acute myocarditis by checking cardiac enzymes and performing a physical examination. Acute myocarditis is rare, but remember to consider these common symptoms and the diagnosis.

Joseph Chamness, DNP, FNP-C, ENP-C, CNE, is a clinical assistant professor at the University of Alabama College of Nursing in Huntsville; Yeow Chye Ng, PhD, CRNP, CPC, FAANP, FAAN, is an associate professor at the University of Alabama College of Nursing.

These letters are from practitioners around the country who want to share their clinical problems, successes, observations, and pearls with their colleagues. We invite you to participate. Submit your Clinical Pearl here


1. Tschöpe C, Ammirati E, Bozkurt B, et al. Myocarditis and inflammatory cardiomyopathy: current evidence and future directions. Nat Rev Cardiol. 2021;18(3):169-193. doi:10.1038/s41569-020-00435-x

2. Ammirati E, Frigerio M, Adler ED, et al. Management of acute myocarditis and chronic inflammatory cardiomyopathy: an expert consensus document. Circ Heart Fail. 2020;13(11):e007405. doi:10.1161/CIRCHEARTFAILURE.120.007405

3. Imazio M, Gaita F, LeWinter M. Evaluation and treatment of pericarditis: a systematic review. JAMA. 2015;314(14):1498-1506. doi:10.1001/jama.2015.12763

4. Kraut JA, Madias NE. Lactic acidosisN Engl J Med. 2014;371(24):2309-2319. doi:10.1056/NEJMra1309483