Scimitar Syndrome: Multimodal Imaging Before and After Repair.

Abstract

A 19-year-old woman was noted on an incidental chest radiograph to have dextroposition of the heart secondary to a hypoplastic right lung, with a linear opacity to the right of the right atrium extending below the diaphragm (Fig. 1). Although the patient was asymptomatic, a subcostal view via transthoracic echocardiography showed substantial dilation of the right atrium and right ventricle, a pulmonary artery systolic pressure of 27 mmHg, and an abnormal vessel and flow entering a dilated inferior vena cava (IVC) (Fig. 2). Subsequent cardiac catheterization and angiography of the right pulmonary artery revealed complete anomalous right pulmonary venous (PV) drainage from the right lung to the infradiaphragmatic IVC with a pulmonic-to-systemic flow ratio (Qp:Qs) of 2.11:1 (Fig. 3). Cardiac magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) were performed before and after gadofosveset-trisodium contrast administration. This noninvasive study revealed anomalous drainage of the entire right lung into the infrahepatic IVC with a calculated Qp:Qs ratio of 2.1:1, confirmed the prior results, and suggested no anomalous pulmonary arterial supply, left PV drainage, horseshoe lung, or accessory diaphragm (Fig. 4). Because of substantial shunting, the scimitar right PV was repaired by means of an end-to-side anastomosis of the right PV to the left atrium adjacent to the atrial septum (Fig. 5). An outpatient postoperative MRI revealed the surgical connection, a decrease in right ventricular cavity size, and a Qp:Qs of 1:1 (Fig. 6). Postoperatively, the patient did well. Fig. 1. Frontal chest radiograph shows a hypoplastic lung with cardiac dextroposition and a linear opacity to the right of the atrium, extending below the diaphragm (arrows). Fig. 2. Transthoracic echocardiogram in color-flow Doppler mode (subcostal view) shows Doppler inflow (red) of the anomalous right pulmonary vein as it drains into the inferior vena cava. Fig. 3. Right pulmonary arteriogram (anteroposterior projection) shows anomalous pulmonary venous drainage of contrast medium into the inferior vena cava, inferior to the diaphragm (arrows). Fig. 4. Cardiac magnetic resonance image with contrast medium (posterior view in 3-dimensional rendering) defines the entire right pulmonary venous drainage to the infrahepatic inferior vena cava (arrows). Fig. 5. Postoperative frontal chest radiograph shows sternotomy wires and an unchanged heart size, with the cardiac apex lying to the right of the midline. Note the small basilar atelectasis. Fig. 6. Cardiac magnetic resonance angiograms with contrast medium. A) Anterior view shows the surgical connection between the right pulmonary vein and the left atrium. B) Posterior view, in 3-dimensional rendering. Note the postoperative changes associated with ...