Relationship between whole blood viscosity and lower extremity peripheral artery disease severity

Abstract

Aim: Increased blood viscosity (BV) has good correlaton with lower extremity peripheral artery disease (LEAD). However, the relationship between BV and peripheral arterial disease (PAD) anatomical complexity and symptom severity have not been studied adequately so far. The aim of the present study was to assess the relationship between whole blood viscosity (WBV) and LEAD anatomical complexity and symptom severity. Methods: The study included 240 consecutive patients with suspected PAD who had lower extremity peripheral angiography between March 2016 and March 2020. A Transatlantic İntersociety Consensus II (TASC II) A-B lesion was defined as anatomical simple LEAD, and a TASC II C-D lesion was defined as anatomical complex LEAD. Symptom severity of all patients were categorized from 0 to 6 according to Rutherford classification. WBV was assessed using a validated calculation formula derived from hematocrit and total plasma protein levels, both at low (LSR) and high (HSR) shear rate. Results: TASC II C-D group presented significantly higher WBV values both at LSR (40.2 ± 9.5 vs. 46.5 ± 13.2; p < 0.001) and HSR (15.9 ± 0.5 vs. 16.5 ± 0,7; p < 0.001). In ROC analysis, a cut-off value of 16.1 WBV at HSR had 74.5% sensitivity and 68% specificity for predicting TASC II C-D (AUC: 76.2%, p < 0.001) and a cut-off value of 42.9 WBV at LSR had 73.4% sensitivity and 66.6% specificity for predicting TASC II C-D (AUC: 74.2%, p < 0.001). In multivariate analysis, both high WBV at LSR (OR: 2.121, 95% CI: 1.079 – 3.164, p < 0.001) and high WBV at HSR (OR: 2.737, 95% CI: 1.671 – 4.483, p < 0.001) were independent predictors for TASC II C-D. There was a significant positive correlation between WBV at LSR and Rutherford symptom category (0-6) (r = 0.412, p <0.001) and WBV at HSR and Rutherford symptom category (0-6) (r = 0.402, p <0.001). Conclusion: Our data suggests that; increased WBV values may be associated with TASC II C-D lesions, which indicated more anatomically complex LEAD. Also WBV values positively correlated with Rutherford symptom severity