https://orcid.org/0000-0001-6858-109X
A 55-year-old previously healthy woman, hospitalized in the intensive care unit with Legionella pneumonia (Panel A, black arrow), presented sudden onset dyspnoea and chest pain. Physical exam revealed signs of heart failure, and electrocardiogram showed 2 mm inferoposterior ST-segment elevation with 1.5 mm aVR ST-segment depression (Panel B). An urgent invasive coronary angiography was performed and showed non-obstructive coronary disease. Transthoracic echocardiography showed a moderate left ventricular dysfunction, and serum biomarkers of myocardial injury were markedly elevated. Due to all these findings and raising the suspicion of acute myocarditis, a cardiac magnetic resonance was scheduled demonstrating an area of oedema in the anterior, anterolateral, and inferior medium segments and anterior and inferior apical segments (Panel C, grey arrows), as well as late subepicardial and intramyocardial gadolinium enhancement in the same areas (Panel D, grey arrows), thus confirming the diagnosis of myocarditis. Anti-inflammatory therapy and neurohormonal treatment were started. At hospital discharge, the patient was asymptomatic, and transthoracic echocardiography showed a normal left ventricular function.
Despite its very low prevalence, myocarditis must be suspected as a Legionella pneumonia complication. Although extrapulmonary manifestations are rare, cardiac involvement is the most prevalent, and it can be present as myocarditis, pericarditis, and prosthetic valve endocarditis. A systematic diagnostic workup is necessary to establish early recognition of the underlying cause and guide specific therapy to prevent further and permanent myocardial damage. Beyond, the usefulness of cardiac magnetic resonance for the diagnosis of myocarditis must be highlighted if Lake Louise criteria are met.
Conflict of interest: None declared.
