P1766 Comparison of left ventricular stroke volume in healthy adults among regions around the world: results from the World Alliance of Societies of Echocardiography (WASE) Normal Values Study

Abstract

Abstract Funding Acknowledgements WASE Normal Values Study is sponsored by American Society Echocardiography Foundation. OnBehalf the WASE Investigators Background The American Society of Echocardiography (ASE) and the European Association of Cardiovascular Imaging (EACVI) chamber quantification guidelines provide normal reference values for a variety of size and function parameters. While used worldwide, these were predominantly obtained from American and European Caucasian populations and may not represent individuals from other regions around the world. Accordingly, ASE in collaboration with its International Alliance Partners conducted the World Alliance of Societies of Echocardiography (WASE) Normal Values Study to establish and compare normal echocardiographic values across races, ethnicities and countries worldwide. While most previous studies focused on left ventricular (LV) size and ejection fraction, LV stroke volume (SV) in healthy normal subjects has not been well defined. In this report, we aim to examine similarities and differences in normal LV SV indexed by body surface area (SVI) among regions around the world. Methods WASE Normal Values Study is a multinational, observational, cross-sectional study. Individuals free from known cardiac, lung and renal disease were prospectively enrolled with even distribution among age groups and gender. Echocardiographic images were acquired following a standardized protocol. LV SV was assessed by Doppler-derived (LVOT diameter and VTI) and two-dimensional (2D) biplane Simpson’s methods. LV SVI was calculated to account for differences in body size. These measurements were analyzed (TOMTEC) in a single core laboratory following ASE/EACVI Guidelines. Results As of May 2019, LV SV has been analyzed in 1164 cases from 13 countries, representing 8 distinct regions worldwide. In this population, age, body surface area and 2D LV ejection fraction were 47 ± 17 years old (range 18-87 years old), 1.76 ± 0.22 m² (range 0.95-2.44 m²) and 63.2 ± 2.9 % (range 52.7-73.7 %), respectively. LV SV and SVI by Doppler were larger than those obtained by 2D method in all regions. LV SV and SVI in both methods had significant differences among regions (p< 0.0001, Kruskal-Wallis test). LV SV and SVI in South Asia (India) were smallest in both methods and were also significantly smaller than other Asian regions (Figure). North America and Europe had largest LV SV and SVI by Doppler method, while Oceania had largest values by 2D. Conclusions The WASE Normal Values Study shows geographical variability in LV SVI across continents and countries. This information should be considered when determining normative values for SV and SVI. Abstract P1766 Figure.