Aims: To assess accuracy and reproducibility of real time simultaneous triplane echocardiography (RT3PE) for the assessment of left ventricular (LV) volumes and ejection fraction (EF) using cardiac magnetic resonance (CMR) as a reference method.
Methods and results: A total of 24 patients with various degrees of LV dysfunction (EF from 36 to 57%) in sinus rhythm with good image quality were enrolled in the study. Digital loops of apical views were recorded with standard two-dimensional imaging and with RT3PE. Echocardiography and CMR were performed within 1 hour. RT3PE measurements of LV end-diastolic volume, end-systolic volume, and EF resulted closely correlated to CMR (r = 0.95, 0.97, and 0.95, respectively) with small biases (-4 ml, -6 ml, and 1%, respectively) and narrow limits of agreement (SD = 15 ml, 12 ml, and 6%, respectively). Two-dimensional echocardiography (2DE) showed a weaker correlation with CMR (r = 0.85, 0.91, and 0.83, respectively; P < 0.06) with similar biases (-4 ml, -10 ml, 5%, respectively), but wider limits of agreement (SD = 28 ml, 21 ml, 10%, respectively, P < 0.007). RT3PE showed lower interobserver variability for the assessment of EF (SD = 2% vs. 5%, P = 0.03) and lower measurement time of LV EF (175 +/- 54 sec vs. 241 +/- 49 sec, respectively; P < 0.0001), as compared to 2DE.
Conclusion: RT3PE allows simple and fast image acquisition and volume calculation. In addition, it allows more accurate and reproducible EF measurements than conventional 2DE.