Eisenmenger syndrome: is it the same entity in adulthood and pediatric age?
Authors: Playan Escribano J , Garrido-Lestache E , Cristo Ropero M J , Alvarez Fuente M , Barbera J A , Moreno Galdo A , Rueda Soriano J , Rodriguez Ogando A , Elias Hernandez T , Guillen Rodriguez I , Lazaro Salvador M , Lozano Balseiro M , Lara Padron A , Escribano Subias P , Del Cerro Marin M J 
Published: October 2021

Abstract

Introduction
Eisenmenger syndrome is the final clinical stage of different congenital heart diseases (CHD) associated with pulmonary arterial hypertension (PAH). Children born in recent years with CHD have benefited from advances in pediatric cardiac surgery that have modified their evolution compared to adults with the same pathologies.

Purpose
Our objective was to define and compare the characteristics and prognosis of the adult and pediatric population with Eisenmenger Syndrome.

Methods
REHAP and REHIPED are Spanish, voluntary, multicenter registries that include patients with PAH associated with CHD. REHAP started in 2007 and includes patients over 18 years of age. Patients diagnosed with PAH after this time were prospectively included, until 2020. Patients who were followed in the participating centres and diagnosed after January 1998 were retrospectively included in the registry. REHIPED started in 2009 and collects patients between 2 months and 18 years of age. Patients diagnosed with PAH after this time were prospectively included, until 2020. Patients who were followed and diagnosed after January 1998 were retrospectively included. The baseline characteristics, hemodynamic profile, treatment, and 10-year survival of the REHAP patients were compared to those included in the REHIPED.

Results
Eisenmenger syndrome is the main clinical group in adults (56% of patients with PAH associated with CHD enlisted in REHAP), 371 patients were included. On the other hand, Eisenmenger syndrome is the least frequent clinical group in childhood (21% of patients with PAH associated with CHD enlisted in REHIPED), 32 patients were included. Among adults, simple defects were significatively more common, whereas complex defects were more frequent in children (p 0.004). Half of the patients were in NYHA class III-IV, with no difference between groups. Adults presented greater hemodynamic severity, with higher mean pulmonary arterial pressure and greater pulmonary vascular resistance index. There were no differences in treatment: neither in first line therapy nor in the percentage of patients who received prostanoids at any time during follow up. The usage of prostanoids was very low in both groups. Two-thirds of the patients who died or underwent transplantation did so without taking prostanoids at any time. The 10-years survival analysis showed no significative difference between groups.

Conclusions
The prevalence of Eisenmenger syndrome is clearly lower in the pediatric population with CHD compared to the adult population. However, once Eisenmenger syndrome has developed, even though adults present greater hemodynamic severity, the clinical characteristics and the prognosis are similar in both groups. The usage of prostanoids is low in adulthood and in childhood, even in those with more severe forms of the disease.

Funding Acknowledgement
Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Ferrer, MSD, Janssen, GSK Table 1Figure 1