Implications of methods for calculating the left ventricular outflow tract area in aortic stenosis severity grading

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main source(s): - Spanish Ministry Economy and Competitiveness through the Carlos III Institute Health-Fondo de Investigación Sanitaria. Post-residency research contract. Medical Research Hospital La Fe (IIS Fe), Valencia, Spain. Introduction Aortic valve area (AVA) calculation by continuity equation is a fundamental aspect to estimate aortic stenosis (AS) severity. The estimation left ventricular outflow tract (LVOT) source technical variability in AVA that can lead errors severity grading. Formulas for calculating LVOT diameter (LVOTd) based on body surface (BSA) patient height have been proposed, but their impact reclassifying patients has not described. Purpose To evaluate differences AS grading according used AVA. Methods We retrospectively analyzed (2019–2022) 1722 echocardiograms with diagnosis following variables reported: calculated using equation, weight patient. Predicted LVOTd BSA was formula: (5.7*BSA + 12). as: (5.78 * 12.1). Results from predicted showed slightly higher values. associated lower prevalence severe AS, as well discordant cases (mean gradient <40 mmHg <1 cm2) (Table). both methods led reclassification (by standard method) non-severe significant percentage (13.6% BSA-predicted method, 8.7% height-predicted method). For BSA, "downgrade" more frequent (23.3%) quartile highest BMI (>30 kg/m2), while degree obesity did affect method height. Conclusion Despite suppressing potential derived measurement, or terms due low gradient. In obese patients, highly patient's preferable.