Vasodilator Therapy in Children: Acute and Chronic Effects in Children with Left Ventricular Dysfunction or Mitral Regurgitation

To determine the acute and chronic effects of vasodilator therapy in children, vasodilator therapy was evaluated in 13 children (aged 0.2 to 14.5 years) with severe left ventricular dysfunction or mitral regurgitation. In seven children, nitroprusside increased cardiac index by an average of 33% (P less than .01) and increased stroke index by 29% (P less than .01). In eight children, hydralazine caused a 31% increase in cardiac index (P less than .01) and a 27% increase in stroke index (P less than .02). Ten children received chronic oral vasodilator therapy and were followed for 5.7 +/- 1.4 (SEM) months. Early clinical improvement was observed in every child. Symptoms of heart failure diminished in all, and five children became entirely asymptomatic. A significant (P less than .05) improvement was noted in growth velocity, respiratory rate, heart size, and incidence of gallop rhythm after 1 month of therapy. The duration of the beneficial response to vasodilator therapy varied considerably, however, and significant improvement for the group was not found after 1 month. Four children had sustained clinical improvement for 6 months or longer, but the others experienced recurrent heart failure within 1 to 4 months.