Prevalence of Inferior Vena Cava Anomalies and Their Significance and Impact in Clinical Practice

Abstract

To evaluate the prevalence of inferior vena cava (IVC) anomalies in an asymptomatic healthy population and symptomatic patients. This was a multicentre retrospective observational study This study was conducted by reviewing the computed tomography (CT) images of 1 000 individuals from South Korea taken for a general medical check up (group A) and 1 000 patients from the USA who visited with various symptoms for which CT was required (group B). A third group of 800 patients with deep vein thrombosis (DVT) and CT from two US centres were used for comparison (group C). Twenty-eight patients with anatomical changes in the IVC due to intervention, extrinsic compression, trauma, other rare conditions, and poor image quality were excluded. The mean age ± standard deviation of each group was 50 ± 6, 54 ± 11, and 54 ± 15 years in groups A, B, and C, respectively. In group A, duplication was the most common anomaly (10 cases, 1.0%), followed by left sided IVC (four cases, 0.4%), hypoplasia (three cases, 0.3%), and megacava (one case, 0.1%). In group B, the most common IVC anomaly was hypoplasia in six cases (0.6%); duplication in three patients, left sided IVC in three patients, aplasia in two patients, web formation in two patients, and megacava in two patients. In group C, hypoplasia was the most common type (32 cases, 4.0%). The prevalence of hypoplasia in patients younger than 50 years of age was significantly higher compared with older patients (12.7% [14/110] vs. 5.3% [10/190]; p = .027). The risk of hypoplasia or aplasia was significantly higher in patients with DVT (odds ratio [OR] 17.032, 95% confidence interval [CI] 5.243 – 55.321), especially in patients with iliofemoral DVT (OR 34.211, 95% CI 10.323 – 113.378). In the normal group, IVC duplication was the most common variation, while hypoplasia was most common in patients with iliofemoral DVT, especially in younger ones.