The impact of surgical aortic valve replacement on myocardial deformation in patients with severe aortic stenosis: a comparison between echocardiography and CMR

Abstract

Abstract Background Aortic valve replacement (AVR) in patients with severe aortic stenosis (AS) leads to reverse remodelling, with reduction in left ventricle (LV) mass and volumes. However, the effect of AVR on left atrial (LA) and LV myocardial deformation using speckle tracking echocardiography (STE) and feature tracking cardiac magnetic resonance (FT-CMR) has not been extensively compared in the same cohort. Methods Patients with severe AS scheduled for AVR were recruited. Same-day TTE and CMR scans were performed pre- and post-AVR using a standard protocol. Myocardial deformation was assessed using STE and FT-CMR by a blinded single observer. LA strain (LAS) corresponding to reservoir, conduit and booster pump function were assessed on 4- and 2-chamber and average values calculated. For the LV, the three long-axis views were utilised for global longitudinal strain (GLS) and peak early diastolic strain rate (PEDSR). Mid circumferential strain (Mid-CS) and PEDSR were calculated from the mid short-axis view. Global circumferential strain (GCS) and PEDSR were derived by averaging values from the basal, mid and apical short axis cine slices by FT-CMR only. Results We recruited 78 patients with severe AS, 66 of whom (mean age 67.0±9.4 years; 75.8% males) had matched pre- and post-AVR CMR scans. Median follow-up period was 6 months. LV assessment by TTE was limited by image quality (>20% unanalysable images). STE demonstrated a significant increase in reservoir and conduit LAS, GLS and longitudinal PEDSR post-AVR (Table 1&2). FT-CMR demonstrated a significant increase in booster-pump LAS, GLS, GCS and longitudinal/ circumferential-PEDSR post-AVR. Conclusion In patients with severe AS, significant increase in LV GLS and longitudinal-PEDSR was seen using both FT-CMR and STE. GCS and circumferential-PEDSR were significantly increased using FT-CMR only, suggesting that CMR may be more sensitive to subtle changes in LV function at 6 months post-AVR. LAS assessment showed significant improvements post-AVR by both imaging modalities.Table 1Table 2