Value of circumferential and radial strain in the early detection of left ventricular systolic dysfunction in patients with myocarditis
Authors: Kalesi A , Theodosis - Georgilas A , Plaitis A , Ntiloudi D , Vasiliadou A , Kalivi A , Tzinieris T , Sagris M , Behlivani I M , Zachos P , Gardikioti V , Pallas A , Destounis A , Patsourakos N , Kasinos N 
Published: January 2025

Abstract

Background
Acute myocarditis typically involves localized myocardial damage that is mainly distributed sub-epicardially, posing challenges to its early detection using conventional echocardiography.

Aim
This study aimed to assess the potential of circumferential and radial strain for early detection of myocardial damage in patients with acute myocarditis and preserved ejection fraction.

Methods
The study retrospectively included all patients admitted to the cardiology clinic of a tertiary hospital between December 2019 and May 2024, with suspected myocarditis, preserved ejection fraction, negative findings for coronary artery disease on coronary angiography or coronary computed tomography angiography. Diagnosis of myocarditis was confirmed using cardiac magnetic resonance imaging (CMR). Gender and age-matched healthy individuals were also enrolled. The echocardiographic parameters assessed included radial and circumferential strain (global, epicardial, mid-myocardial and endocardial circumferential strain) in the parasternal short axis view at the levels of the mitral valve, papillary muscles and apex. Statistical analysis was performed using Mann-Whitney test and the predetermined level of statistical significance was set at p&lt;0.05.

Results
A total of 41 patients (34 males – 82.9%) and 32 healthy controls (25 males – 78%) were included in the study. The median age in the patient group was 28 years (range 16-46 years), and in the healthy controls group, it was 29 years (range 17-48 years). In the patient group, median values were as follows: at the mitral valve level, radial strain (RS) 37.8% and global circumferential strain (GCS) -14.1%; at the papillary muscles level, RS 40.8% and GCS -16.1%; at the apex level, RS 37.3% and GCS -19%. In the healthy controls group, median values were: at the mitral valve level, RS 47.9% and GCS -16.8%; at the papillary muscles level, RS 52% and GCS -18%; at the apex level, RS 41.8% and GCS -18.5%. The circumferential strain values for each layer are presented in Table 1. Patients with acute myocarditis exhibited significantly lower absolute values of radial and circumferential strain at the mitral valve and papillary muscles levels, but not at the apex level (see Image 1). Lower circumferential values were observed across different layers only at the mitral valve level and at the papillary muscles in the epicardial layer.

Conclusion
Our study indicates that circumferential strain (CS) and radial strain (RS) indices at the mitral valve and papillary muscles levels, along with mitral valve CS values at specific layers, could be valuable for early detection of left ventricular dysfunction in patients with myocarditis and preserved ejection fraction. Larger epidemiological studies are required to validate these findings comprehensively.