Central Arterial Stiffness: Methodological Considerations and Clinical Applications

Abstract

Globally, stroke remains the second leading cause of preventable death. In the UK, approximately 1.3 million individuals live with the effects, and this number is expected to increase due to the population ageing, medical care and treatment techniques improving leading to better survival rates. Hypertension is the most important modifiable risk factor, however, arterial stiffness, an independent predictor of stroke, offers additional prognostic value beyond traditional risk factors and may help identify high-risk individuals who might otherwise be overlooked. The gold standard assessment of arterial stiffness is carotid-femoral pulse wave velocity (cfPWV), however, its application has predominately been research based due to high level of expertise required. Therefore, less operator dependent tools, such as brachial-femoral pulse wave velocity (bfPWV), should be explored to mitigate these limitations. Whilst bfPWV could be a promising tool, for it to be considered as a surrogate endpoint it must meet several steps including methodological consensus, clinical utility and ease of use. As such, the overarching aim of this thesis was to explore the methodological considerations associated with bfPWV, initially with a healthy cohort, but then via a series of studies focused on its clinical applications in a stroke population. Findings demonstrated acceptable agreement (Mean difference: -0.3m/s) between cfPWV and bfPWV in a young healthy population (Chapter 5), with the sternal notch to umbilicus and subtraction method providing the most accurate path length estimation and assessments should be taken supine. Within a stroke population, agreement was poor, though values were comparable between the symptomatic (mean difference: -2.4m/s) and asymptomatic (-3.4m/s) sides (Chapter 6). In Chapter 7, the Vicorder device demonstrated excellent between-day reliability, particularly in the supine, asymptomatic limb (ICC: 0.92). Whilst bfPWV typically tracked similar directional changes to cfPWV (rmcorr: 0.59) following a 12-week intermittent pneumatic compression intervention designed to increase physical activity in stroke patients (Chapter 8), the overall agreement when assessing the magnitude of change was poor (ICC: 0.38). As such, while both measures incorporate central components of the arterial tree, cfPWV and bfPWV are not interchangeable and should be considered distinct physiological markers. These findings provide novel methodological insights that support the development of standardised protocols and future guidelines, which will fundamentally identify early functional and morphological changes before the onset of overt disease, and enables timely intervention with the potential to improve clinical outcomes.

Date of Award	4 Jun 2026
Original language	English
Awarding Institution	University of Winchester
Supervisor	James Faulkner (Supervisor) & Hazel J Brown (Supervisor)