Myocardial strain features by 2D-STE during the course of fulminant myocarditis: Correlation with characteristics by CMR and clinical implications

Myocardial strain analysis by 2D speckle tracking echocardiography could determine the left ventricular function. Our purpose is to investigate the global longitudinal strain (GLS) changes during the course of fulminant myocarditis (FM) and evaluate their correlation with cardiac magnetic resonance (CMR). Patients with clinical diagnosis of FM from June 30, 2017 to June 30, 2019 were screened prospectively. 18 survived patients (mean age 34 ± 18 years) who had two scans of transthoracic echocardiography and underwent CMR were included. All patients had severely impaired left ventricular ejection fraction and GLS value at admission that improved significantly before discharge. The patients in the healed stage revealed elevated global native T1 and T2 relaxation time and extracellular volume fraction as well, which were 1408.3 ± 88.3ms, 46.56 ± 5.23ms, and 0.35 ± 0.09, respectively. GLS from the second transthoracic echocardiography in the healed stage correlated significantly with global native T1 relaxation time (r =-0.574, P = .013) and with extracellular volume fraction (r = -0.582, P = .011), but not global native T2 relaxation time (r = -0.31, P = .211) and not with late gadolinium enhancement mass (r = 0.084, P = .743). In comparison, GLS at admission were not correlated with CMR parameters of fibrosis and oedema in the healed stage. GLS by 2D-STE may emerge as a new tool to monitor inflammatory myocardial injuries during the course of FM. FM in the acute healed stage has the presence of both chronic fibrosis and oedema which are correlated with GLS, but GLS at admission can’t predict the early recovery of myocardial inflammation.