Background: The evaluation of diastolic left ventricular function is critical for hypertrophic cardiomyopathy (HCM) evaluation. Myocardial stiffness is known to be an important property for the evaluation of the diastolic myocardial function, but this parameter cannot be measured non-invasively by the existing techniques. Purpose: The goal of our study is to investigate the potential of Shear Wave Imaging (SWI), a novel ultrasound-based technique, to quantify non-invasively the passive diastolic myocardial stiffness in a pediatric population of HCM. Methods: We included prospectively 40 children between five and eighteen years old, 20 healthy volunteer and 20 patients with HCM. A complete clinical echocardiography was as well achieved in all the study population. SWI was performed thanks to a phased-array probe (2.75 MHz central frequency, 96 elements, Super- Sonic Imagine, France) to obtain the shear wave speed (SWS). The acquisition of SWI was performed on the basal antero-septal segment during the end of the diastole with ECG triggering, in a short axis (SA) and long axis (LA) views. SWS were compared between the two groups and analyzed with the clinical parameters of echocardiography. Results: Shear wave imaging was performed successfully in 92% of healthy volunteer and in 95% of HCM patients. The mean SA-SWS was 1.45±0.13 m/s [min=0.99; max=1.58] in the healthy volunteer and 2.25±0.21 m/s [min=1.22; max=3.21] in the HCM patients (p=0.01). The mean LA-SWS was 1.14±0.12 m/s [min=0.87; max=1.51] in the healthy volunteer and 1.91±0.21 m/s [min=1.15; max=2.94] in the HCM (p=0.01). The averaged SWS is higher in SA than in LA (p<0.05 for both group), due essentially to the local elastic anisotropy of the myocardial muscle. Statistical analysis showed good repeatability of SWS measurements. Positive correlations were found between the evaluation of SWS and clinical parameters in echocardiography such as E/A, Ea/E, Ea/Aa IVS thickness, LV mass, LA volume. Conclusion: Non-invasive SWI evaluation of diastolic myocardial stiffness can distinguish healthy children and HCM. SWI could be a new clinical parameter for the diagnosis of HCM.
Villemain, O., Correia, M., Khraiche, D., Podetti, I., Meot, M., Legendre, A., … Pernot, M. (2018, May 1). Myocardial Stiffness Assessment Using Shear Wave Imaging in Pediatric Hypertrophic Cardiomyopathy. JACC: Cardiovascular Imaging. Elsevier Inc. https://doi.org/10.1016/j.jcmg.2017.08.018