Massive Pulmonary Arteriovenous Malformation as a Cause of Fetal Heart Failure

Pulmonary arteriovenous malformations (AVMs) are abnormal connections between the pulmonary arteries and veins that can result in rapid-onset heart failure. We present a case of a fetus with pulmonary AVMs diagnosed at 22 weeks gestation. Fetal echocardiography showed cardiomegaly and dilated pulmonary arteries and veins reflecting the hemodynamic significance of the shunt. Inverted flow through the ductus arteriosus was also present. Fetal autopsy following medical termination of the pregnancy confirmed the morphological findings, including displacement of arteries and veins in proximity to the pleural surface. The genetic study was negative. This report highlights the cardiovascular impact of a rare disorder. Inverted flow through the ductus arteriosus may be another poor prognostic indicator, useful in parental counseling.