Assessment of Early Diastolic Intraventricular Pressure Difference in Children by Blood Speckle-Tracking Echocardiography

Background: The lack of reliable echocardiographic techniques to assess diastolic function in children is a ma-jor clinical limitation. Our aim was to develop and validate the intraventricular pressure difference (IVPD) calcu-lation using blood speckle-tracking (BST) and investigate the method's potential role in the assessment of diastolic function in children. Methods: Blood speckle-tracking allows two-dimensional angle-independent blood flow velocity estimation. Blood speckle-tracking images of left ventricular (LV) inflow from the apical 4-chamber view in 138 controls, 10 patients with dilated cardiomyopathies (DCMs), and 21 patients with hypertrophic cardiomyopathies (HCMs) <18 years of age were analyzed to study LV IVPD during early diastole. Reproducibility of the IVPD analysis was assessed, IVPD estimates from BST and color M mode were compared, and the validity of the BST-based IVPD calculations was tested in a computer flow model. Results: Mean IVPD was significantly higher in controls (-2.28 +/- 0.62 mm Hg) compared with in DCM (-1.21 +/- 0.39 mm Hg, P < .001) and HCM (-1.57 +/- 0.47 mm Hg, P < .001) patients. Feasibility was 88.3% in controls, 80% in DCM patients, and 90.4% in HCM patients. The peak relative negative pressure occurred earlier at the apex than at the base and preceded the peak E-wave LV filling velocity, indicating that it repre-sents diastolic suction. Intraclass correlation coefficients for intra-and interobserver variability were 0.908 and 0.702, respectively. There was a nonsignificant mean difference of 0.15 mm Hg between IVPD from BST and color M mode. Estimation from two-dimensional velocities revealed a difference in peak IVPD of 0.12 mm Hg (6.6%) when simulated in a three-dimensional fluid mechanics model. Conclusions: Intraventricular pressure difference calculation from BST is highly feasible and provides informa-tion on diastolic suction and early filling in children with heart disease. Intraventricular pressure difference was significantly reduced in children with DCM and HCM compared with controls, indicating reduced early dia-stolic suction in these patient groups. (J Am Soc Echocardiogr 2023;36:523-32.)

Automated summary

This study developed and validated the calculation of intraventricular pressure difference (IVPD) using blood speckle-tracking (BST) in children and investigated its potential role in assessing diastolic function. The results showed that BST is highly feasible and provides information on diastolic suction and early filling in children with heart disease. The IVPD was significantly reduced in children with dilated cardiomyopathies (DCMs) and hypertrophic cardiomyopathies (HCMs) compared to controls.