Cardiac anatomy and function in juvenile hypertension. Current understanding and future concerns

Recently, several groups of investigators have independently identified subtle cardiac changes very early in the development of primary hypertension. Echocardiographic evidence for left ventricular hypertrophy has been found in 10 to 15 percent of adolescents with mild persistent hypertension. However, in individual cases and within groups, the relationship between left ventricular mass and random blood pressure measurements was not extremely strong. Factors other than blood pressure probably influence the development of left ventricular hypertrophy in teenagers. Resting left ventricular function and overall estimates of exercise capacity for hypertensive teenagers fell within normal limits. However, during upright bicycle exercise, peak exercise systolic and diastolic pressures, and peak heart rates were significantly higher in hypertensive male and female adolescents compared to normotensive controls. Myocardial oxygen consumption may be considerably higher for hypertensive teenagers at rest and during peak exercise. Juvenile onset essential hypertension and left ventricular hypertrophy may be separate but interrelated long-term cardiovascular risk factors. Uniform echocardiographic methods for assessment of left ventricular anatomy are recommended to provide the basis for systematic, longitudinal studies needed to resolve these important issues.