CORRELATION BETWEEN PULMONARY VASCULAR RESISTANCE AND RED CELL DISTRIBUTION WIDTH IN PULMONARY HYPERTENSION

Abstract

SESSION TITLE: Pulmonary Vascular Disease Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: Red Cell Distribution Width (RDW) is a mathematically derived value, used to evaluate the size variation of red cells. It can be elevated in situations of recent blood loss or transfusion, renal dysfunction, etc. A literature review shows that RDW has been correlated with various cardiac hemodynamic parameters in the setting of pulmonary hypertension (PH). The 6th World Symposium on Pulmonary Hypertension (PH) recently defined pre-capillary PH to include PH patients with a pulmonary vascular resistance (PVR) of over 3 Woods Units (WU). The purpose of this study was to determine the presence of a correlation between RDW and PVR. METHODS: Patients who underwent right heart catheterization (RHC) at our center between November 2014 and November 2019 were included in this retrospective study. Exclusion criteria included patients under the age of 18, active malignancy, known hemoglobinopathy, blood transfusion within one month of laboratory testing, and patients without an RDW measured within 3 months of RHC. Hemodynamic parameters obtained on RHC were documented, along with RDW values from the closest CBC obtained within 3 months of the RHC. Student’s t-test was used to compare PVR between patients with elevated RDW (> 14.5%) and normal RDW (= 14.5%). Additionally, RDW was compared between patients with elevated PVR (> 3 WU) and those without. RESULTS: 306 patients were included in this study. The elevated RDW group (> 14.5%, n = 117) tended to have a higher PVR than normal RDW group (= 14.5%, n = 189), and this was found to be statistically significant (3.02 vs 2.43 WU, p = 0.495). On the other hand, patients with an elevated PVR (= 3 WU, n = 71) were also found to higher RDW than the non-elevated PVR (< 3 WU, n = 235) group, in a statistically significant fashion (15.05 vs 14.31%, p = 0.0369). CONCLUSIONS: This study implies that a statistically significant correlation exists between PVR and RDW. The elevation of RDW in the setting of an elevated PVR could be due to the fact that RDW is tied to the severity of inflammatory state. PH likely has an inflammatory component; there have been studies demonstrating increased expression of C-reactive protein receptor lectin-like oxidized low-density lipoprotein receptor-1 the pulmonary vasculature cells of patients with CTEPH. Furthermore, endothelial dysfunction, inflammation, and smooth muscle proliferation is causative of elevations in PVR. CLINICAL IMPLICATIONS: Given the importance of PVR in the classification of PH, a cheap biomarker to predict the PVR in patients with PH would be of utility. RDW could serve useful in this setting, however, larger studies are needed to validate this association. DISCLOSURES: No relevant relationships by Syed Haider, source=Admin input No relevant relationships by Pius Ochieng, source=Web Response No relevant relationships by Divya Ravi, source=Web Response No relevant relationships by NISHANT SHARMA, source=Web Response No relevant relationships by Metlapalli Venkata Sravanthi, source=Web Response No relevant relationships by Pandi Todhe, source=Web Response