Dr. Stephan Moll writes…..
When a young person is diagnosed with extensive pelvic DVT or a clot in the big vein in the abdomen, the inferior vena cava (IVC), it is worthwhile to ask whether that person has some congenital abnormality of the IVC, such as a congenital absence or narrowing of the IVC.
Abnormalities of the IVC are not common, but do occur (ref 1-4). They typically do not cause any symptoms, and are classically only incidentally discovered during abdominal surgery or when an abdominal CT is done for some unrelated reason. However, occasionally these IVC narrowings or interruptions lead to the formation of blood clots in the IVC or in the pelvic veins (deep vein thrombosis = DVT) due to disturbance of blood flow. In one study (ref 2), 5 of 31 patients (i.e. 15 %of patients) with DVT of the pelvic veins had some abnormality of the IVC and these patients were all young (between 20 and 35 years of age). Thus, in the young person with a spontaneous DVT, the suspicion for the presence of an IVC abnormality is increased. A vascular radiologist looking at the X-ray studies (CT venogram, conventional contrast venogram, or MRI venogram) may be able to comment on whether there is anything unusual about the anatomy of the IVC.
It is often appropriate to treat a patient with DVT associated with an IVC abnormality with long-term blood thinners, as the anatomic abnormality that lead to the clot is permanent. However, decisions on length of blood thinner therapy always need to be individualized.
- Lane D: Congenital hypoplasia of the inferior vena cava: an underappreciated cause of deep vein thromboses among young adults. Military Medicine 2005;170(9):739-742.
- Obernoster A et al: Anomalies of the inferior vena cava in patients with iliac venous thrombosis. Ann Intern Med 2002;136:37-41.
- Kellman GM et al. Computer tomography of vena caval anomalies with embyologic correlation. Radiographics. 1988 May;8(3):533-56.
- Lamber M et al. Inferior vena cava agenesis and deep vein thrombosis: 10 patients and review of the literature. Vasc Med 2010;15:451-9.
Last updated: Feb 29th, 2012