Abstract 11399: Evaluation of a New 3D Doppler Flow Method to Quantify Flow at the Mitral Valve and Left Ventricular Outflow Tract: An in vitro Study

Abstract

Back ground: The aim of this study was to test a new 3D Doppler flow quantification method for mitral inflow and left ventricular outflow at different stroke volumes in a controlled phantom study.

Methods: Four freshly harvested pig hearts were studied in a water tank. Each heart was pumped at different SVs (40 to 80ml) using a calibrated pump at increments of 10ml. Four-dimensional flow volumes were obtained using a 4Z1c 2.8MHz transducer on Acuson SC2000 scanner (Siemens Medical Solutions). The digital imaging data was analyzed offline using prototype software. Hemispheric flow sampling planes for color Doppler velocity measurements were placed at the mitral inflow and left ventricular outflow tract (LVOT).

Results: This novel 3D Doppler flow quantification tool detected incremental increases in mitral inflow and LVOT outflow in accordance with pumped stroke volume (Mitral inflow: R² = 0.7549, LVOT outflow: R² = 0.7113, p< 0.05). Bland-Altman analyses demonstrated underestimation (mitral inflow:-5.97483, LVOT outflow: -4.73306) with both 97% of points within a 95% CI.

Conclusion: This new 3D flow quantification tool is accurate and feasible.