(185) IVC Size Matters: Can a Chest CT Reveal Ventricular Dysfunction?

Introduction: Undiagnosed ventricular systolic dysfunction is seen in various ICU settings. While a flattened IVC on CT correlates with hypovolemia, the value of IVC distension on CT is not clear. We hypothesize that IVC size, contrast reflux and ventricular dimensions on CT would be greater in patients with ventricular dysfunction (VD) diagnosed by echocardiography(echo).

Methods: We retrospectively reviewed charts of adult patients (2022-2023) in a single hospital system who received an echo and a CT within 24 hours of each other. Presence of VD was defined as having left ventricular systolic dysfunction (LVSD) (LVEF ≤45%), right ventricular systolic dysfunction (RVSD) (TAPSE ≤17mm, FAC < 35% or septal flattening/bowing) on echo. VD, isolated LVSD (iLVSD), and isolated RVSD (iRVSD) were correlated with CT imaging findings of IVC diameter (IVC-D, mm), IVC area (IVC-A, mm2), R:L ventricle ratio (RLVR) and contrast reflux. We report median, interquartile range, and p-values.

Results: 495 patients met inclusion criteria. 91 (18.4%) patients were found to have VD; 24 (4.8%) had iRVSD and 48 (9.7%) had iLVSD. Comparing patients with VD to those without VD, both IVC-D and IVC-A were larger (29 (26-33) vs 28 (25-31), p=0.01 and 529 (434-694) vs 479 (381-597), p = 0.004, respectively). The RLVR was 0.9 (0.8-1.1) in both groups (p = 0.27). Contrast reflux was seen in 19 patients (3.8%), of whom 7 had VD and 4 had iRVSD. The RLVR on CT correlated meaningfully to demonstrate the location of VD (iLVSD 0.87 vs iRVSD 1 vs no VD 0.93, p=0.003)
These results remained significant after accounting for potential confounders including PEEP >8 and inotrope usage.

Conclusions: IVC diameter and area are greater in patients with VD compared to those without VD. Our data suggests that evidence of IVC distension on CT may identify patients requiring further cardiac investigation. Ventricular size ratio may suggest iLVSD and iRVSD. We also identify IVC area as a reliable measurement of IVC size on static imaging. Future research should identify patterns of VD most likely to correlate with IVC size, ventricular ratios and contrast reflux on CT scan, and to identify reliable cutoff values for IVC sizes of concern.