Congenital anomalies of the IVC-embryological perspective and clinical relevance

Abstract

With the increased use of cross-sectional imaging, systemic venous anomalies are more frequently being recognized in asymptomatic patients. Accurate characterization of systemic venous anomalies plays a major role in the appropriate selection of a surgical approach or interventional procedure. In this article, we review common and uncommon inferior vena cava (IVC) anomalies. We describe the embryological basis and clinical implications of these anomalies, particularly from an interventional radiology perspective. We also discuss the complications and treatments of these anomalies.

Keywords: Inferior vena cava (IVC); anomalies; embryology.

Figure 1

Schematic diagram showing venous drainage of the embryo at 4 weeks of life; SV, sinus venosus. There are broadly three venous systems: the vitelline venous system draining the gut, the umbilical venous system draining the placenta, and the cardinal venous system draining the rest of the embryo.

Figure 2

Schematic diagram showing early formation of the posterior cardinal veins (brown), subcardinal veins (green), and supracardinal veins (blue).

Figure 3

Schematic diagram showing 4 IVC segments during fetal development. Suprahepatic IVC (red) originates from the vitelline venous system; suprarenal/infrahepatic IVC (green) originates from the subcardinal venous system; infrarenal IVC (brown) originates from the supracardinal venous system; and iliac veins and their confluence (purple) originate from the posterior cardinal system.

Figure 4

Axial CT (A) and sagittal MRI images (B) showing an IVC (arrow) opening into the left atrium (LA).

Figure 5

Coronal maximal intensity projection of MR angiography showing an anomalous pulmonary vein on the right (arrow), which is extending inferiorly to the diaphragm and drain into the IVC (curved arrow), giving a “Scimitar” appearance. The right lower pulmonary artery is hypoplastic.

Figure 6

Abernethy type I malformation. (A) Coronal reconstruction of a contrast enhanced CT showing the IVC (arrow), with no visible connection to the portal vein; (B) coronal maximal intensity projection showing the superior mesenteric vein/splenic confluence (arrow) joining the IVC; (C) ultrasound greyscale image correlation showing the absence of the portal vein at the portosplenic confluence

Figure 7

Microcatheter in superior mesenteric vein/splenic vein confluence, with no flow distally into the portal circulation (18). Available online: http://www.asvide.com/articles/1296

Figure 8

Absence of hepatic IVC with azygos continuation. (A) Coronal Steady state free precession (SSFR) MR image showing absence of the hepatic IVC (arrow) with azygos continuation (curved arrow) (B) axial SSFP MR image showing absence of the hepatic IVC (C) axial SSFP MR image showing continuation of the IVC as a dilated azygos vein (arrow) (D) coronal SSFP MR showing absence of the hepatic IVC (arrow) with azygos continuation (curved arrow).

Figure 9

Interruption of the suprarenal portion of the IVC with azygos continuation (25). Available online: http://www.asvide.com/articles/1297

Figure 10

Absent infrarenal IVC. (A-C) Serial axial CT images through the abdomen A Prominent azygos (arrow) and hemiazygos (curved arrow) veins at the level of the diaphragm; (B) termination of IVC at the level of the renal veins; (C) complete absence of the infrarenal IVC; (D) coronal maximal intensity projection showing a patent intrahepatic and suprarenal IVC (arrow) with absence below the level of the kidneys

Figure 11

Duplicated IVC. (A,B) Axial CT images showing duplicated IVCs (arrows) joining at the renal vein level. This patient was treated with bilateral filter insertions (see Figure 12).

Figure 12

AP Abdominal radiograph showing bilateral IVC filters (arrows) placed in the patient imaged in Figure 11A,B.

Figure 13

Circumaortic left renal vein. (A-C) Coronal and 2 axial images showing the left posterior (B, arrow) and anterior (C, arrow) renal veins encircling the aorta.

Figure 14

Complete left IVC (arrowhead). (A) Axial CT image showing the IVC on the left; (B) coronal maximal intensity and (C) coronal reconstruction images of the IVC segment that crosses the midline (arrowhead) to join the normal right suprarenal IVC.

Figure 15

Retrocaval ureter. (A) Axial and (B) coronal images showing the right ureter (curved arrow) posterior and medial to the IVC (arrow).

Figure 16

Axial image showing a retroaortic left renal vein (arrow) connecting to the IVC (curved arrow).