Assessment of conduit artery vasomotion using photoplethysmography

Abstract

Vasomotion is a spontaneous oscillation of vascular tone. The phenomenon has been observed in small arterioles and capillaries as well as in the large conduit arteries. The layer of smooth muscle cells that surrounds a blood vessel can spontaneously and periodically change its tension and thereby the arterial wall stiffness also changes. As the understanding of the phenomenon is still rather obscure, researchers would benefit from a low-cost and reliable investigation technique such as photoplethysmography (PPG). PPG is an optical blood pulsation measurement technique that can offer substantial information about the arterial stiffness. The aims of this pilot study were to evaluate the usefulness of the PPG technique in the research of vasomotion and to investigate vasomotion in the relatively large conduit arteries. Continuous 15 minute long measurements of posterior tibial artery wall stiffness were taken. Artery diameter, electrocardiogram, blood pressure and respiration were also simultaneously registered. Fast Fourier Transform power spectra were calculated to identify unique stiffness oscillations that did not correspond to fluctuations in the systemic parameters and thus would indicate vasomotion. We concluded that photoplethysmography is a convenient method for the research of the vasomotion in large arteries. Local stiffness parameter b/a is more accurate to use and easier to measure than the pulse wave velocity which describes stiffness of a segment of an artery. Conduit arteries might exhibit a low amplitude high frequency vasomotion ( 9 to 27 cycles per minute). Low frequency vasomotion is problematic to distinguish from the passive oscillations imposed by the arterial pressure.

Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography

“…The M wave is known to represent the 0.1 Hz fundamental oscillation of mean arterial pressure. It is one of the vascular signatures that can be derived from peripheral PPG through spectral analysis (Kanders et al, 2013).…”

“…As seen in Figure 3, that the PPG signal has a clear high-frequency peak (at the cardiac frequency) and a strong low-frequency peak (<0.5 Hz). The PPG signal has been used as a noninvasive way to directly assess vasomotion (Kanders et al, 2013). The 0.1 Hz frequency band contributes 26%…”

“…The high-frequency PPG signal (0.2-0.5 Hz) is generally attributed to respiratory effects, while the lower-frequency component (0.05-0.15 Hz) is associated with sympathetic regulation of peripheral vascular resistance (Anschütz & Schubert, 2005;Krupatkin, 2009) as well as M waves (Allan et al, 2018;Bernardi et al, 1996;Middleton et al, 2011). Indeed, PPG has been used to identify a 0.1 Hz power-spectral peak (9-27 cycles per minute), which could stem from either vasomotion or the M wave (Kanders, Grabovskis, Marcinkevics, & Aivars, 2013;Kiselev et al, 2020). From a clinical perspective, there is increasing recognition of the PPG signal as a means to provide cuffless measures of vascular health (Attarpour, Mahnam, Aminitabar, & Samani, 2019;Kanders et al, 2013).…”

“…Indeed, PPG has been used to identify a 0.1 Hz power-spectral peak (9-27 cycles per minute), which could stem from either vasomotion or the M wave (Kanders, Grabovskis, Marcinkevics, & Aivars, 2013;Kiselev et al, 2020). From a clinical perspective, there is increasing recognition of the PPG signal as a means to provide cuffless measures of vascular health (Attarpour, Mahnam, Aminitabar, & Samani, 2019;Kanders et al, 2013). More recently, low-frequency PPG variance has been suggested to provide a noninvasive estimation of blood pressure, either through simple signal modeling (Sharma et al, 2017) or through machine learning (Attarpour et al, 2019).…”

Vascular origins of low-frequency oscillations in the cerebrospinal fluid signal in resting-state fMRI: Interpretation using photoplethysmography

“…It is clear, as seen in Figure 3, that the PPG signal has a clear high-frequency peak (at the cardiac frequency) and a strong low-frequency peak (< 0.5 Hz). The PPG signal has been used as a noninvasive way to directly assess vasomotion (Kanders et al, 2013). The B-wave and M-wave frequency bands contribute ~5% and 26% to the PPG signal ( Figure 5 & 6).…”