Clinical and hemodynamic effect of endothelin receptor antagonists in Eisenmenger Syndrome

Endothelin receptor antagonists (ERAs) are widely accepted as a specific treatment for pulmonary arterial hypertension. Unfortunately, consensus and recommendations are lacking for the treatment of patients who suffer from pulmonary arterial hypertension and congenital heart disease, including Eisenmenger syndrome.

This meta-analysis aimed to compare the effect of ERA on patients with Eisenmenger syndrome.

Electronic search on PubMed (MEDLINE), EBSCO, EuropePMC, Clinicaltrials.gov, and Google Scholar was done. Studies involving the use of ERAs on Eisenmenger syndrome patients were included. There were 18 studies included. The primary outcome of interest was the 6-min walking test distance before and after exposure to ERA.

There were 517 patients with Eisenmenger syndrome. The subjects had Eisenmenger syndrome secondary to congenital heart disorders, with WHO functional Class ranging from Class I-IV. The follow-up ranges from a mean of 4-60 months. Seventeen studies reported a statistically significant difference between pretreatment and the posttreatment result of 6-min walking test distance. Pooled mean difference comparing pre and posttreatment values yielded an increase of 55.24 m (42.15, 68.33) P < 0.001; moderate heterogeneity I ² 51% P = 0.008. Pooled mean pulmonary vascular resistance index difference comparing pre and posttreatment values yielded a decrease of 4.76 woods unit (-6.86, -2.66), P < 0.001 favoring posttreatment; low heterogeneity I2 0%, P = 0.82. Pooled mean mean pulmonary arterial pressure difference comparing pre and posttreatment values yielded a decrease of 5.40 mmHg (-7.53, -3.28), P < 0.001 favoring posttreatment, low heterogeneity I ² 0%, P = 0.65.

Implementation of ERA in Eisenmenger improves 6-min walking distance and pulmonary vascular pressure indices. Earlier administration of ERA might be beneficial, further studies are needed to assess mortality benefit of this agent.