Eisenmenger Syndrome

8% of all CHD pts.

11% of pts with intracardiac or aortopulmonary shunt, allowing continuous exposure of pulm vasculature to systemic arterial pressure.

VSD is the most common lesion.

High risk of cardiovascular complications when undergoing noncardiac surgery; mortality reaching 30%.

Severity of pulm Htn cyanosis, tricuspid regurgitation, and right ventricular dysfunction are important factors.

Additional acquired cardiac and systemic diseases, such as CAD and renal dysfunction.

Underlying pathology, urgency, duration of surgery, and anesthetic choice contribute to the risk.

Bleeding due to platelet dysfunction.

Mortality rate of pts with ES carrying pregnancy to viability is 27−30%, most often at delivery or postpartum.

Fetal risks: Increased risk of preterm labor and intrauterine growth retardation; fetal demise of 75%.

Cesarean section carries higher mortality: 70% versus 30% for vaginal delivery.

R-to-L shunt, pulm Htn, RV and LV ventricular failure, hypoxemia, polycythemia.

Minor decrease in SBP can cause increase in R-to-L shunt, decreased pulm blood flow, hypoxia, and cardiovascular collapse.

Increased blood viscosity can lead to thromboembolic phenomena, paradoxical emboli, hemoptysis.

Arrhythmias, ventricular and supraventricular.

May not tolerate positive pressure ventilation.

Decreased systemic vascular resistance of pregnancy worsens R-to-L shunt.

Inability to meet increased demand for O ₂ with gestation and labor.

Delivery produces autotransfusion with RV failure.

Excessive bleeding with previous heparinization.

Postpartum increase in PVR.

ES is defined as pulm Htn at systemic level due to high PVR with reversed or bidirectional shunt through communication between the two circulations.

Communication may be at aortic level (PDA, aortopulmonary window), intracardiac (ASD, VSD, AV canal, TAPVR) or single ventricle.

Uncorrected L-to-R shunt leads to irreversible fixed pulm vascular obstructive disease.

Characterized by pulm Htn, R-to-L shunt, and RV dysfunction.

Overall poor prognosis; mean age at death: 25 y.

Syncope, increased right-sided filling pressures, and systemic arterial desaturation below 85% indicate poor prognosis.

50% of pregnant pts die in association with pregnancy.

Some pulm vascular reactivity may exist in the pulm vasculature of pregnant women; may be due to systemic hormonal changes of pregnancy.

Individuals with large unrestricted intracardiac or aortopulmonary communication have large L (systemic)-to-R (pulm) shunts.

Uncorrected L-to-R shunt overloads pulm vasculature and RV.

Continuous exposure to systemic pressure leads to pulm arteriolar medial hypertrophy, intimal proliferation, and fibrosis.

Progressive pulm capillary and arteriolar occlusion leads to fixed increased PVR.

As pulm pressure exceeds systemic, shunt reverses to R to L.