Long-term hemodynamic effects of nifedipine on congenital heart disease with eisenmenger's mechanism in children

Abstract

The hemodynamic effect of long-term nifedipine medication was studied in 10 children, 3-12 years of age, five with ventricular septal defect and five with complete atrioventricular septal defect; all had Eisenmenger's reaction, seven also had Down's syndrome. They underwent heart catheterization prior to and during 1-4 years of nifedipine therapy. Fick's principle was used to calculate the ratio of pulmonary arterial pressure to aortic pressure (PAP/PAO), the ratio of pulmonary flow to aortic flow (QP/QS), as well as the ratio of pulmonary vascular resistance to aortic vascular resistance (RP/RS). In the seven children under 8.8 years, nifedipine caused a significant drop in PAP/PAO (p less than 0.004), a slight increase in arterial O2 saturation, a significant increase in QP/QS (p less than 0.02), and a decrease in RP/RS (p less than 0.02). The nifedipine effect was age related. On nifedipine, breathing oxygen resulted in, independent of age, a significant increase in QP/QS (p less than 0.003) and a significant decrease in PAP/PAO (p less than 0.04) and in RP/RS (p less than 0.003). Direct O2 consumption measurements before and during oxygen breathing in six patients demonstrated no significant change in RP, RS, QP, or QS indices. Nifedipine had a relaxing effect on the pulmonary vascular bed, especially in the younger child with Eisenmenger's mechanism. On nifedipine therapy, O2 produced a more complex hemodynamic reaction that was not restricted to the pulmonary circulation alone.

Pulmonary arterial hypertension in congenital cardiac disease – the need for refinement of the Evian-Venice classification

“…By definition, those patients with the true Eisenmenger syndrome are unable to fulfil the definitions of the acute responder, as described by Sitbon et al, 29 because the unrestricted defect leads to equalisation of pulmonary and systemic arterial pressures. Although an incidental study has reported a beneficial haemodynamic effect of calcium-blockade in children with the true Eisenmenger syndrome, 30 in general this therapy has not been accepted by the experts for the use in these patients.…”

The Adult Patient with Eisenmenger Syndrome: A Medical Update after Dana Point Part II: Medical Treatment - Study Results

“…Studies have shown inhaled NO to reduce pulmonary vascular resistance with minimal systemic effects in patients with ES and acute pulmonary hypertensive states of other etiologies [8, 9]. Amongst these, beneficial hemodynamic effects have been anecdotally described in children with ES [10]. …”

Unusual multiple spasm during coronary angioplasty

“…22 23 Medical treatment (calcium channel entry blockers, prostacyclin) for primary pulmonary hypertension is of proven clinical benefit, [24][25][26][27][28] while the success of medical treatment in children with obstructive pulmonary hypertension remains controversial and varies with age. [29][30][31] In older patients, treatment with calcium channel entry blockers is less beneficial and this has stimulated interest in new treatments. One of these is inhalation of NO, a selective pulmonary vasodilator, which reduces the degree of pulmonary hypertension in newborn infants with persistent pulmonary hypertension.…”