Acute myocarditis: prognostic role of speckle tracking echocardiography and comparison with cardiac magnetic resonance features.

To evaluate longitudinal systolic function in patients with myocarditis, its correlation with cardiac magnetic resonance (CMR) features, and its predictive value in functional recovery and arrhythmias onset during follow-up (FU) on optimized medical therapy (OMT). Patients with acute myocarditis, confirmed through CMR criteria, and age- and sex-matched healthy controls were enrolled. Two-dimensional (2D) transthoracic echocardiography, including speckle tracking analysis, was performed at admission and after 6 months of FU. Patients of myocarditis group also underwent 24 h ECG Holter monitoring during FU. 115 patients with myocarditis (mean age 41 ± 17, 70% males) and 70 healthy subjects were enrolled. Global longitudinal strain (GLS) and sub-epicardial strain were markedly lower in the myocarditis group than in controls (mean GLS%: − 14.1 ± 5.1 vs − 23.1 ± 3.6, p   − 12%; sensitivity84%; specificity74.4%; AUC = 0.75). Parameters of myocardial longitudinal deformation are importantly associated with the presence of a scar on CMR and are predictors of functional outcome and ventricular arrhythmias in patients with acute myocarditis. Their assessment during ultrasound examination should be considered to get more information about the prognosis and risk stratification of this subset of patients.