Ebstein Repair in a High-Altitude Setting ≥2,500 m: First Experience from Bolivia

Abstract

Background

Contemporary surgical approaches for Ebstein anomaly are based on a paradigm shift towards earlier surgery in order to avoid the deleterious effects of chronic right ventricular (RV) volume overload. In addition, RV dysfunction may worsen in the setting of high altitude, and to date, no results on Ebstein anomaly surgery have been reported from a high-altitude setting.

Methods

We herein present first postoperative results from Ebstein anomaly patients who underwent cone reconstruction (with or without bidirectional Glenn anastomosis) in Cochabamba, Bolivia (>2,500 m above sea level) using a specific high-altitude protocol for prophylactic medical treatment of presumed pulmonary hypertension (PH), including sildenafil, iloprost, and higher FiO₂.

Results

Four patients underwent surgical correction of Ebstein anomaly (median age 9 years, range 4–12 years, all female). Ebstein anomaly was classified as Carpentier type C in three and as Carpentier Type B in one patient. All patients showed some degree of atrial shunting while one patient exhibited an additional perimembranous ventricular septal defect. All underwent cone reconstruction of the tricuspid valve. Due to massive intraoperative bleeding, which required rethoracotomy, subsequently causing impaired RV function, one patient underwent concomitant “one and a half ventricle” repair. All other patients showed an uncomplicated postoperative course and all were alive with a good and/or improved RV function and only minimal-to-mild tricuspid regurgitation after 1 year.

Discussion

Cone reconstruction in children with Ebstein anomaly is feasible in a high-altitude setting when using a dedicated protocol to prophylactically manage PH.

Keywords

Ebstein anomaly - cone reconstruction - bidirectional Glenn anastomosis - high altitude - middle- and low-income regions

Publication History

Received: 12 July 2024

Accepted: 21 May 2025

Accepted Manuscript online:
26 May 2025

Article published online:
24 June 2025

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