Impact of Pulmonary Hemodynamics and Ventricular Interdependence on Left Ventricular Diastolic Function in Children With Pulmonary Hypertension

Abstract

Background Through ventricular interdependence, pulmonary hypertension (PH) induces left ventricular (LV) dysfunction. We hypothesized that pediatric PH patients have LV diastolic dysfunction, related to adverse pulmonary hemodynamics, leftward septal shift, and prolonged right ventricular (RV) systole. Methods and Results Echocardiography was prospectively performed at two institutions in 54 pediatric PH patients during cardiac catheterization, and in 54 matched controls. Diastolic LV measures including myocardial deformation were assessed by echocardiography. PH patients had evidence of LV diastolic dysfunction, most consistent with impaired LV relaxation, though some features of reduced ventricular compliance were present. PH patients demonstrated the following: reduced mitral E velocity and inflow duration, mitral E’ and E’/A’, septal E’ and A’, pulmonary vein S and D wave velocities, and LV basal global early diastolic circumferential strain rate; and increased mitral E deceleration time, LV isovolumic relaxation time, mitral E/E’, and pulmonary vein A wave duration. PH patients demonstrated leftward septal shift and prolonged RV systole, both known to affect LV diastole. These changes were exacerbated in severe PH. There were no statistically significant differences in diastolic measures between patients with and without a shunt, and minimal differences between patients with and without congenital heart disease. Multiple echocardiographic LV diastolic parameters demonstrated weak to moderate correlations with invasively-determined PH severity, leftward septal shift, and prolonged RV systole. Conclusions Pediatric PH patients exhibit LV diastolic dysfunction most consistent with impaired relaxation and reduced myocardial deformation, related to invasive hemodynamics, leftward septal shift, and prolonged RV systole.

Ventricular Dysfunction, Interdependence, and Mechanical Dispersion in Newborn Infants with Congenital Diaphragmatic Hernia

“…We observed a correlation between LV and RV longitudinal systolic function in CDH cases indicating increased ventricular interdependence, as has previously been observed in children and adults with PAH [19]. …”

Left Ventricular Diastolic Dysfunction in Pediatric Pulmonary Hypertension

“…Impaired LV filling likely contributes to impaired LV stroke volume and, hence, cardiac output, and the current article emphasizes the need to assess this better in children and adults with PAH. Although foremost emphasis is placed on RV systolic dysfunction in PAH, diastolic dysfunction, and in this particular study, 27 LV diastolic function, is abnormal and may be important to clinical outcome. …”

“…In this issue of Circulation: Cardiovascular Imaging, Burkett et al 27 present the results of a 2-center, prospective, ventricular function study combining conventional (B-mode, Doppler), biventricular deformation imaging and tissue Doppler imaging and near-simultaneous cardiac catheterization in 54 pediatric PH patients and in 54 age-, sex-, and institution-matched controls. All PH children underwent right heart catheterization at diagnosis or follow-up and were classified as having precapillary PH (here, mean PA pressure ≥25 mm Hg and PAWP <15 mm Hg).…”

“…A deformation imaging (speckle tracking) study on the identical cohort of pediatric PH patients had identified decreased systolic LV strain/strain rate, predominantly within the septum, with relationships to invasive hemodynamics, RV strain, and functional PH measures. 25 In the current study, 27 the authors aimed to study the impact of pulmonary hemodynamics and ventricular interdependence on LV diastolic function in pediatric PH. By doing so, they directed their focus beyond RV systolic dysfunction that is known to determine clinical outcome but often is a late finding, particularly in younger patients, and even in those with advanced PAH.…”

“…By doing so, they directed their focus beyond RV systolic dysfunction that is known to determine clinical outcome but often is a late finding, particularly in younger patients, and even in those with advanced PAH. Burkett et al 27 show that children with PH exhibit LV diastolic dysfunction most consistent with impaired LV relaxation and decreased myocardial deformation, related to invasive hemodynamics, leftward septal shift, and prolonged RV systole. There were no statistically significant differences in diastolic measures between patients with and without a shunt, and minimal differences between patients with and without congenital heart disease.…”