Analysis of global systolic and diastolic left ventricular performance using volume-time curves by real-time three-dimensional echocardiography

Background: Left ventricular (IV) volume-time curves (VTC) have been described to provide quantitative data on the dynamics of global IV performance beyond ejection fraction. However, generation of VTCs by conventional 2-dimensional imaging techniques is inherently limited because of inaccurate geometric volume assumptions. We, therefore, studied whether the new concept of volumetric scanning as realized by real-time 3-dimensional echocardiography (RT-3DE) can be used to provide accurate VTCs. Methods: In 30 healthy participants, VTCs were generated from 18 to 24 absolute IV volumes per second by transthoracic RT-3DE and compared with magnetic resonance imaging (MRI) used for reference. LVs were traced manually in 9 to 11 parallel, short-axis planes and volumes calculated by disk method. From VTCs, we determined peak ejection rate (PER), peak early filling rate (PFR), time to PER and PFR, and end-diastolic and end-systolic volumes. For initial clinical application, 2 patient groups of coronary (n = 15) and hypertensive heart disease (n 16) were studied. Results: In healthy participants, VTCs agreed with MRI (mean errors: PER, -39 +/- 67 mL/s; PFR, - 18 +/- 84 mL/s; time to PER, 8 21 milliseconds; time to PFR 4 +/- 18 milliseconds [not significant vs 0]) whereas VTCs in coronary and hypertensive groups revealed significantly impaired diastolic function. Scanning time for VTCs was only I to 2 minutes by RT-3DE and 8 +/- 2 minutes by MRI (P < .001) and time for offline analysis was 22 +/- 5 minutes versus 24 +/- 4 minutes by MRI (not significant). Conclusions. Generation of VTCs by RT-3DE is feasible and shows excellent agreement with MRI used for reference. Thus, VTCs by RT-3DE is a promising new approach providing access to quantitative information on global IV performance such as IV filling rates that is currently unavailable for the cardiologist.