Two-Dimensional Strain Echocardiography Reveals Myocardial Dysfunction in Symptomatic Normal-Flow Low-Gradient Aortic Stenosis: Insights for Transcatheter Aortic Valve Implantation Decision-Making and Prognostic Assessment

Background: Since the decision to proceed with valve re- placement remains controversial due to conflicting prog- nostic evidence, the use of normal-flow low-gradient aor- tic stenosis (NFLGAS) presents a clinical dilemma. Thus, this study aimed to evaluate the clinical utility of two- dimensional strain echocardiography (2D-STE) in distin- guishing therapeutic outcomes between transcatheter aortic valve implantation (TAVI) and conservative management in patients with NFLG AS. Methods: This retrospective cross-sectional study analyzed 97 patients diagnosed with NFLG AS between October 2019 and June 2023. Patients were divided into two groups based on treatment strategy: 34 underwent TAVI, and 63 received conservative management. Clinical data were collected at baseline, discharge, and 6-month follow-up. Key echocardiographic parameters included left ventricular (LV) ejection fraction (LVEF), aortic valve area (AVA), relative wall thickness (RWT), obtained via transthoracic echocardiography (TTE), and LV global longitudinal strain (LVGLS) measured using 2D-STE. Multivariable linear regression models were used to adjust for potential confounding factors. Kaplan–Meier analysis was employed to compare 6-month cardiac event-related readmission rates between the two groups. Results: Preoperatively, the mean LVGLS was –14.2% ± 1.5%. In the TAVI group, LVGLS significantly improved to –16.7% ± 1.4% at discharge and further to –18.5% ± 1.3% at 6-month follow-up (p < 0.001). After adjusting for potential confounders, the improvement in LVGLS remained significant in the TAVI group (p < 0.001). In contrast, the conservative management group showed no significant changes in LVGLS across the same time points (–14.0% ± 1.8%, –14.2% ± 1.6%, and –14.7% ± 2.2%, respectively; p = 0.118). The TAVI group also exhibited a significantly lower 6-month cardiac event-related readmission rate compared to the conservative group (χ2 = 4.53; p = 0.033; hazard ratio (HR) = 0.47, 95% confidence interval (CI): 0.24–0.94). Conclusion: These preliminary findings suggest that TAVI may offer significant improvements in LVGLS and reduce short-term cardiac event-related readmissions in symptomatic NFLG AS patients. Nonetheless, further validation in larger, prospective studies is warranted to confirm these potential clinical benefits.