Related Experiment Videos
Endogenous dilator prostaglandins in congenital heart disease
C Hammerman1, M J Aramburo, K C Bui
1Department of Pediatrics, University of Chicago, IL 60637.
Insights
Neonates with cyanotic congenital heart disease show elevated prostacyclin levels, contributing to persistent ductus arteriosus. This finding is crucial for managing ductal-dependent heart conditions in newborns.
Area of Science:
- Neonatal Cardiology
- Pediatric Cardiovascular Research
- Congenital Heart Disease Pathophysiology
Background:
- Maintaining ductal patency is vital for neonates with ductal-dependent congenital heart disease awaiting surgery.
- Spontaneous delay in ductal closure is observed in newborns with critical pulmonic stenosis.
- The role of endogenous prostaglandins in prolonged ductal patency requires investigation.
Purpose of the Study:
- To investigate if infants with ductal-dependent congenital heart lesions exhibit increased dilator prostaglandins, prolonging ductal patency.
- To compare prostaglandin levels in neonates with cyanotic lesions versus left ventricular obstructive lesions.
Main Methods:
- Studied six neonates with cyanotic lesions (group 1) and six with left ventricular obstructive lesions (group 2).
- Measured circulating prostaglandin E2 (PGE2) levels.
- Assessed plasma 6-keto PGF1 alpha (a prostacyclin metabolite) and arterial oxygen partial pressure (PaO2).
Main Results:
- Circulating PGE2 levels were not elevated in either group.
- Plasma 6-keto PGF1 alpha levels were significantly higher in the cyanotic group (3143 +/- 1844 pg/ml) compared to controls (< 500 pg/ml).
- Hypoxia (lower PaO2) was observed in the cyanotic group (36 +/- 15 mmHg) compared to the obstructive group (72 +/- 34 mmHg).
Conclusions:
- Increased synthesis or release of prostacyclin, potentially triggered by hypoxia, may contribute to persistent ductus arteriosus in neonates with cyanotic ductal-dependent lesions.
- Prostacyclin, not PGE2, appears to play a role in maintaining ductal patency in this specific population.
- Findings suggest a mechanism for delayed ductal closure in cyanotic heart disease.
Abstract:
Maintaining patency of the ductus arteriosus pending surgical intervention can be critical to the survival of the neonate with ductal dependent congenital heart disease. Spontaneously delayed ductal closure has been observed clinically and experimentally in newborns with critical pulmonic stenosis. Infants with ductal dependent congenital heart lesions were therefore studied to ascertain whether there was an endogenous increase in dilator prostaglandins prolonging ductal patency. Six neonates with cyanotic lesions (group 1) and six with left ventricular obstructive lesions (group 2) were studied. Circulating PGE2 was not increased in either group. The levels of plasma 6 keto PGF1 alpha, a stable hydrolysis product of prostacyclin, were found to be elevated, but only in the cyanotic group (3143 +/- 1844 vs 404 +/- 250 pg/ml; p less than 0.05; normal less than 500 pg/ml). As expected, PaO2's were also different (36 +/- 15 vs 72 +/- 34 mmHg; p less than 0.05). It is speculated, therefore, that increased synthesis and/or release of prostacyclin, possibly mediated by the hypoxia of the cyanotic ductal dependent lesion, contributes to persistent patency of the ductus arteriosus.