High-definition blood flow imaging improves quantification of left ventricular volumes and ejection fraction.

ABSTRACT

AIMS: The accuracy and reproducibility of echocardiography to quantify left ventricular ejection fraction (LVEF) is limited due to image quality. High-definition blood flow imaging is a new technique which improves cavity delineation without the need for medication or intravenous access. We sought to examine the impact of high-definition blood flow imaging on accuracy and reproducibility of LV systolic function assessment. METHODS AND RESULTS: Prospective observational study of consecutive patients undergoing 2D and 3D transthoracic echocardiography (TTE), high-definition blood flow imaging, and cardiac magnetic resonance (CMR) within 1 h of each other. Left ventricular systolic function characterized by left ventricular end-systolic volumes and left ventricular end-diastolic volumes and LVEF were measured. Seventy-six patients were included. Correlation of 2D TTE with CMR was modest (r = 0.68) with a worse correlation in patients with three or more segments not visualized (r = 0.58). High-definition blood flow imaging was feasible in all patients, and the correlation of LVEF with CMR was excellent (r = 0.88). The differences between 2D, high-definition blood flow, and 3D TTE compared to CMR were 5 ± 9%, 2 ± 5%, and 1 ± 3%, respectively. The proportion of patients where the grade of LV function was correctly classified improved from 72.3% using 2D TTE to 92.8% using high-definition blood flow imaging. 3D TTE also had excellent correlation with CMR (r = 0.97) however was only feasible in 72.4% of patients. CONCLUSION: High-definition blood flow imaging is highly feasible and significantly improves the diagnostic accuracy and grading of LV function compared to 2D echocardiography.