Simple equations to predict the effects of veno-venous ECMO in decompensated Eisenmenger syndrome

Abstract

Adult patients with uncorrected congenital heart diseases and chronic intracardiac shunt may develop Eisenmenger syndrome (ES) due to progressive increase of pulmonary vascular resistance, with significant morbidity and mortality. Acute decompensation of ES in conditions promoting a further increase of pulmonary vascular resistance, such as pulmonary embolism or pneumonia, can precipitate major arterial hypoxia and death. In such conditions, increasing systemic oxygenation with veno-venous extracorporeal membrane oxygenation (VV-ECMO) could be life-saving, serving as a bridge to treat a potential reversible cause for the decompensation, or to urgent lung transplantation. Anticipating the effects of VV-ECMO in this setting could ease the clinical decision to initiate such therapeutic strategy. Here, we present a series of equations to accurately predict the effects of VV-ECMO on arterial oxygenation in ES and illustrate this point by a case of ES decompensation with refractory hypoxaemia consecutive to an acute respiratory failure due to viral pneumonia.

Keywords: ECMO; Eisenmenger syndrome; Extracorporeal membrane oxygenation; Hypoxaemia; Veno-venous.

Figure 1

Echocardiographic investigations. (A) Four‐chamber view showing a dilated, hypertrophied right ventricle and bi‐atrial dilation. (B) Parasternal short‐axis view at the level of the left ventricular outflow tract (LVOT) showing the doubly committed ventricular septal defect (VSD). (C) Colour Doppler M‐mode performed during a routine visit before current hospitalization, showing a bidirectional shunt with a left‐to‐right shunt in early and mid‐systole (yellow arrow) and a right‐to‐left shunt in late systole and in diastole (green arrows), as well as a pulmonary insufficiency (white arrow). (D) Colour Doppler M‐mode performed on admission, showing an increase in the duration of the right‐to‐left shunt (green arrows), relative to the left‐to‐right shunt (yellow arrow). LA, left atrium; LV, left ventricle; PV, pulmonary valve; RA, right atrium; RV, right ventricle; TV, tricuspid valve.

Figure 2

Radiological investigations. (A) Evolution of bilateral pneumonia on sequential chest X‐rays obtained under veno‐venous extracorporeal membrane oxygenation (VV‐ECMO) at Day 1, Day 7, Day 14, and 1 day after VV‐ECMO weaning. (B) Contrast‐enhanced computed tomography scans of the chest showing massive bilateral pneumonia and severe dilation of the pulmonary artery trunk at Day 2 and Day 14 of VV‐ECMO support. (C) Native computed tomography scan of the chest obtained at 6 months of follow‐up showing resolution of the bilateral pneumonia.