Pulmonary Embolism, Thrombectomy, and Catheter-Directed Lysis in Pregnant Woman With Fontan Palliation

Abstract

Background: Patients with Fontan circulation are at increased risk for thrombosis, particularly during pregnancy.

Case summary: A 26-year-old woman at 10 weeks gestation with a lateral tunnel Fontan experienced acute onset of dyspnea and dizziness. Cardiac CT demonstrated an occlusive pulmonary embolism within the Fontan circulation. The patient underwent pulmonary thrombectomy and catheter-directed thrombolysis without complications. A surveillance cardiac CT 3 months after her discharge demonstrated complete resolution of the thrombus, and the patient is at baseline functional capacity.

Discussion: Patients with Fontan circulation and pregnancy have a heightened risk for both thromboembolism and bleeding; anticoagulation strategies are thus not standardized and are tailored to each individual's case.

Take-home messages: To our knowledge, this is the first reported case of pulmonary embolism during the antepartum period in a patient with Fontan palliation who was subsequently treated with pulmonary thrombectomy and catheter-directed thrombolysis. Multimodality imaging evaluation was critical for rapid diagnosis and interventional planning.

Keywords: 3-dimensional imaging; Fontan; congenital heart disease; echocardiography; right-sided catheterization; thrombus.

Graphical abstract

Figure 1

Central Illustration of Patient's Fontan Physiology Diagram of patient’s anatomy demonstrating double-outlet right ventricle, ventricular septal defect, bilateral superior vena cavae, and multilevel pulmonary stenosis palliated with a hemi-Fontan and then fenestrated lateral tunnel Fontan. Blue arrow indicates direction of deoxygenated blood. Red arrow indicates direction of oxygenated blood. LA = left atrium; LV = left ventricle; RA = right atrium; RV = right ventricle.

Figure 2

2D and Color Echocardiography Suprasternal short-axis view on transthoracic echocardiogram in (A) 2-D imaging and (B) color flow demonstrating an echodensity (yellow arrow) at the right superior caval-pulmonary artery anastomosis. Flow is seen in the distal left pulmonary artery but not in the right pulmonary artery.

Figure 3

CT Before Thrombectomy and Cardiac Catheterization Before and After Thrombectomy Cardiac CT axial (A) and coronal (B) views using dual injection of contrast material via the bilateral superior vena cava and delayed venous phase acquisition demonstrating an occlusive pulmonary embolism involving the stented central and right pulmonary artery, with extension into the lateral tunnel of the Fontan (blue arrow). Cardiac catheterization with power injection into the lateral tunnel Fontan (C) before thrombectomy demonstrates a large thrombus with near occlusion of flow into the left pulmonary artery (blue arrow). After thrombectomy (D) there is improved flow into the left pulmonary artery.

Figure 4

CT Surveillance Imaging Cardiac CT axial views (A, B) after cardiac catheterization with thrombectomy and lytic therapy demonstrating decreased thrombus within the LPA stent, improved clot distally within the left lower lobe pulmonary artery branches, and some residual thrombus in the right main pulmonary artery (blue arrow). (C, D) Surveillance cardiac CT at 3 months demonstrating complete resolution of thrombus in the LPA stent, right pulmonary artery, and the lateral Fontan.