A pilot study to assess peak systolic velocity as possible marker of atherosclerotic burden using ultrasound

Introduction: Ischemic heart disease (IHD) has been associated with lower peak systolic velocity (PSV) on penile Doppler measurements [1]. This study establishes whether carotid ultrasound (US) PSV was associated with computational fluid dynamics (CFD) outputs, which in turn may contribute to IHD pathogenesis. Methods: A sample of 57 subjects (with IHD: 27, without IHD: 30) had US velocity profiles (left- common carotid artery) determined between 10e12 equispaced points. Bezier curve fitting was used to fit the profile through the measured velocity points for a normalised diameter. PSV was correlated against CFD results such as wall shear stress (WSS) [2]. Difference in PSV between individuals with/without IHD was studied via t-test. Linear regression was carried out to see if peak systolic velocity was associated with CFD outputs. Any significant associations were analysed within stratified groups (with/without IHD). Results: PSV was significantly lower (p Z 0.042) in subjects with IHD (with IHD: 53.6 17.3 cm/s, without IHD: 62.8 16.1 cm/s). PSV was associated with carotid bulb average pressure drop (p < 0.001), area of average bulb WSS (<1 Pa: p Z 0.016, <2 Pa: p Z 0.006, <3 Pa: p Z 0.001). All the above associations remained significant in individuals with IHD (average bulb pressure drop: p Z 0.001, average bulb WSS (<1 Pa: p Z 0.013, <2 Pa: p Z 0.008, <3 Pa: p Z 0.003). In subjects without IHD, PSV was associated with only average bulb pressure drop (p Z 0.016). Conclusions: This study suggests that further work on PSV and its associations with CFD outputs is required in individuals with and without IHD in various vascular beds.