Angiotensin-converting enzyme inhibition and pre-superior cavopulmonary connection haemodynamics in infants with single-ventricle physiology.

INTRODUCTION

Preliminary animal and human data suggest that angiotensin-converting enzyme inhibition has a role in pulmonary vascular remodelling. We sought to assess the effect of ACEi versus placebo on pulmonary artery pressure and transpulmonary gradient amongst infants undergoing single-ventricle palliation.

MATERIALS AND METHODS

Using the publicly available Pediatric Heart Network Infant Single-Ventricle trial dataset, we compared mean PA pressure at pre-superior cavopulmonary connection catheterisation (primary outcome), transpulmonary gradient, pulmonary-to-systemic flow ratio, and post-SCPC oxygen saturation (secondary outcomes) in infants receiving enalapril versus placebo.

RESULTS

A total of 179 infants underwent pre-SCPC catheterisation, of which 85 (47%) received enalapril. There was no difference between the enalapril and placebo group in the primary and the secondary outcomes. Mean PA pressure in the enalapril group was 13.1 ± 2.9 compared to 13.7 ± 3.4 mmHg in the placebo group. The transpulmonary gradient was 6.7 ± 2.5 versus 6.9 ± 3.2 mmHg in the enalapril and placebo groups, respectively. The pulmonary-to-systemic flow ratio was 1.1 ± 0.5 in the enalapril group versus 1.0 ± 0.5 in the placebo group and the post-SCPC saturation was 83.1 ± 5.0% in the enalapril group versus 82.2 ± 5.3% in the placebo group. In the pre-specified subgroup analyses comparing enalapril and placebo according to ventricular morphology and shunt type, there was no difference in the primary and secondary outcomes.

CONCLUSION

ACEi did not impact mean pulmonary artery pressure or transpulmonary gradient amongst infants with single-ventricle physiology prior to SCPC palliation.