Sensitivities of in vivo markers of arterial organ damage in patients with peripheral atherosclerosis

BACKGROUND: Biomarkers of vascular diseases such as ankle-brachial index (ABI), peripheral pulse pressure (pPP), central pulse pressure (cPP), and pulse wave velocity (PWV) allow assessment of arterial organ damage (AOD). However, the utility of markers other than ABI in patients with peripheral arterial disease (PAD), which are also associated with a significant increase of cardiovascular events, remains unclear. PATIENTS AND METHODS: Asymptomatic (n = 21) and symptomatic patients (n = 46) with a positive sonography for PAD or history of lower limb revascularization were included. ABI, pPP, cPP, and PWV were assessed. PWV were performed using a brachial cuff-based method (aortic PWV (aPWV)) and oscillography (carotid-femoral pulse wave velocity (cfPWV)), respectively. The two methods for PWV were compared using Bland Altman analysis. Sensitivities of ABI, pPP, cPP, cfPWV, and aPWV for AOD were calculated. RESULTS: Sixty-seven patients (35.8 % female, mean age 69, range 39-91 years) had a significantly higher aPWV than cfPWV (median 10.5 m/s (IQR: 8.8-12.65 m/s) vs. median 9.0 m/s (IQR: 7.57-10.55 m/s), p = 0.0013). There was no correlation between cfPWV and age (r = 0.311, p = 0.116). Bland Altman analysis revealed a mean difference of -1.04 (-2SD; -6.38 to + 2SD; 4.31). The sensitivities for AOD were 68.7 % for ABI, 61.2 % for aPWV, 40.3 % for cfPWV, 31.3 % for peripheral PP, and 10.4 % for central aortic PP (p < 0.001). CONCLUSIONS: Brachial-derived aPWV differs from the gold standard assessment (cfPWV), which may be underestimated in PAD due to atherosclerotic obstructions along the aorto-iliac segment. The sensitivities of noninvasive in vivo markers of AOD vary widely and tend to underestimate the actual presence of AOD.