Cardiac and Vascular Target Organ Damage in Pediatric Hypertension

Abstract

Atherosclerosis begins in youth and is associated with the presence of numerous modifiable cardiovascular (CV) risk factors, including hypertension. Pediatric hypertension has increased in prevalence since the 1980s but has plateaued in recent years. Elevated blood pressure levels are associated with impairments to cardiac and vascular structure and both systolic and diastolic function. Blood pressure-related increases in left ventricular mass (LVM) and abnormalities in cardiac function are associated with hard CV events in adulthood. In addition to cardiac changes, key vascular changes occur in hypertensive youth and adults. These include thickening of the arteries, increased arterial stiffness, and decreased endothelial function. This review summarizes the epidemiologic burden of pediatric hypertension, its associations with target organ damage (TOD) of the cardiac and vascular systems, and the impact of these adverse CV changes on morbidity and mortality in adulthood.

Keywords: cardiac function; echocardiography; hypertension; left ventricular mass; target organ damage; vascular function.

Figure 1

Longitudinal tissue Doppler imaging (TDI) obtained from an apical four-chamber view. The septal portion of the mitral valve is sampled. The peak early diastolic velocity (e′) and the peak late diastolic velocity (a′, representing atrial contraction) are demonstrated.

Figure 2

Linear regression analysis of global strain in the echocardiographic four-chamber view, plotted against systolic blood pressure. Data (unpublished to date) obtained from adolescents undergoing a study of the cardiac and vascular effects of obesity and type 2 diabetes mellitus. Global strain reduced with increasing systolic blood pressure values.

Figure 3

Femoral artery pulse wave velocity (PWV) assessment. Directly following an assessment of the carotid artery, an ECG-gated assessment of the PWV at the femoral artery is performed to evaluate the speed by which blood moves along the arterial tree.

Figure 4

Pulse wave velocity (PWV) at baseline and at a 5-year follow-up in a population of adolescents undergoing a study of the cardiac and vascular effects of obesity and type 2 diabetes mellitus (data unpublished to date). Participants are categorized based on their blood pressure category (normotensive or hypertensive) at baseline and at follow-up. Participants who were hypertensive at baseline and normotensive at follow-up had an improvement in PWV. Normotensive participants who were hypertensive at follow-up had increased PWV. Participants who were hypertensive at baseline and at follow-up had increased PWV at both time points with evidence of a progression of PWV at the follow-up. NT, normotensive; HTN, hypertension.