The Diagnostic Role of Speckle Tracking Echocardiography-derived Right Ventricular Longitudinal Strain in Determining the Severity of Rheumatic Mitral Stenosis

Abstract

Introduction: The echocardiographic planimetry is the primary and most available modality for diagnosing Rheumatic mitral stenosis (MS). However, this approach is significantly reliant on the examination technique. The echocardiographic evaluation of MS should also include RV function evaluation for its prognostic role. In this study, we hypothesized that the assessment of RV function using speckle tracking echocardiography (STE) might also have a diagnostic role in determining the severity of MS.

Methods and materials: This cross-sectional study included 47 patients with a definite diagnosis of rheumatic MS. The echocardiographic data were recorded and evaluated offline by an expert cardiologist. The right ventricular global longitudinal strain (RVGLS), right ventricular free wall longitudinal strain (RVFWLS), mitral valve area (MVA) using 2-D planimetry, and other conventional parameters of MS severity were measured. The Statistical Package for Social Science (SPSS) version 26 and Python 3.10.6 were used to analyze and visualize the collected data.

Results: Our analysis showed both RVGLS (R=-0.598, p <0.05) and RVFWLS (R=-0.620, p <0.05) were significantly correlated with MVA. The mean RVGLS in the severe and progressive MS patients were -14.44 ± 4.36 and -18.12 ± 3.25 (p=0.017). The mean RVFWLS values also demonstrated a significant difference between these two groups (-16.3 ± 4.7 vs -20.8 ± 3.2, p=0.005). The area under the curve (AUC) for RVGLS and RVFWLS in detecting severe MS was 0.75 (95% Confidence Interval: 0.64 - 0.86) and 0.78 (95% Confidence Interval: 0.66 - 0.90), respectively.

Conclusion: RVGLS and RVFWLS significantly correlate with MVA and may serve as a tool to assess the severity of rheumatic mitral stenosis in daily clinical practice. RVGLS and RVFWLS have high sensitivity for ruling out severe MS and assessing the severity of MS during routine echocardiographic evaluation.