Feasibility of using a reliable automated Doppler flow velocity measurements for research and clinical practices

Abstract

Echocardiographers are often unkeen to make the considerable time investment to make additional multiple measurements of Doppler velocity. Main hurdle to obtaining multiple measurements is the time required to manually trace a series of Doppler traces. To make it easier to analyse more beats, we present an automated system for Doppler envelope quantification. It analyses long Doppler strips, spanning many heartbeats, and does not require the electrocardiogram to isolate individual beats. We tested its measurement of velocity-time-integral and peak-velocity against the reference standard defined as the average of three experts who each made three separate measurements. The automated measurements of velocity-time-integral showed strong correspondence (R² = 0.94) and good Bland-Altman agreement (SD = 6.92%) with the reference consensus expert values, and indeed performed as well as the individual experts (R² = 0.90 to 0.96, SD = 5.66% to 7.64%). The same performance was observed for peak-velocities; (R² = 0.98, SD = 2.95%) and (R² = 0.93 to 0.98, SD = 2.94% to 5.12%). This automated technology allows <10 times as many beats to be acquired and analysed compared to the conventional manual approach, with each beat maintaining its accuracy.