Influence of sex and age on inferior vena cava diameter and implications for the implantation of vena cava filters.

ABSTRACT

Background: Measuring the venous diameter and choosing a compatible vena cava filter are essential to reduce the risk of complications resulting from implantation of these devices. However, there is little information on how the diameter of the inferior vena cava varies with sex and age. Objectives: To determine the influence of patients' gender and age on their inferior vena cava diameter and the suitability of the different models of available filters. Methods: Retrospective analytical study based on computed tomography images. The diameter of the inferior vena cava was measured at 3 points above the confluence of the common iliac veins, below the renal veins, and midway between these two points (cranial point, caudal point, and midpoint) using Arya® and Carestream PACS® software. The results were classified by sex and age groups. Results: CT scans of 417 patients were analyzed 245 women and 172 men. The diameters at the midpoint and caudal point were, respectively, 19.1 mm and 20.6 mm in women from 81 to 92 years old and were statistically smaller (p< 0.05) when compared to women aged 19 to 40 years (midpoint 22.7 mm; caudal point 23 mm). Similar results were seen in men. Venous diameters at the cranial and caudal points in patients aged from 51 to 70 years were statistically larger in men (cranial point 24.4 mm; caudal point22.3 mm) than in women (cranial point 22.6 mm; caudal point20.8 mm) (p< 0.05). Conclusions: A smaller diameter was found for the inferior vena cava in older patients of both sexes and the rate of diameter change was similar among men and women.