Cardiac size and function during adrenocorticotropic hormone-induced systolic systemic hypertension in infants

The effects of adrenocorticotropic hormone (ACTH) on systolic blood pressure, and echocardiographic indexes of heart size and function were investigated in 14 infants. After 25 days (range 13 to 46) of treatment with ACTH, systolic blood pressure increased from 93 ± 9 to 118 ± 20 mm Hg (p <0.001; mean ± 1 SD). Systolic hypertension (systolic blood pressure greater than the 95th percentile for age) developed in 10 of 14 infants and was associated with an increase in left ventricular (LV) shortening fraction from 41 ± 5% to 52 ± 8% (p <0.001). Myocardial hypertrophy and an increase in echocardiographic indexes of myocardial contractility were observed also. To assess the temporal relation between the onset of systolic hypertension and these cardiac changes, data from 8 infants with serial echocardiograms and blood pressure determinations were examined. After a mean 14 days (range 8 to 18) of ACTH, LV shortening fraction increased from 39 ± 6% to 53 ± 8% (p <0.01), whereas systolic blood pressure remained normal in 7 of 8 infants. In addition, a decrease in LV end-systolic dimension was observed during this early phase. This report documents myocardial changes in individual patients, which occur before and during the development of systolic hypertension.