Determination of radial artery compliance can increase the diagnostic power of pulse wave velocity measurement

Abstract

Pulse wave velocity (PWV) is an indicator associated with the arterial stiffness. Although this technique has been used in the diagnosis of systemic arterial hypertension (SAH), it cannot supply alone enough information about the pathogenesis of this disturbance. This paper aims to determine the compliance of brachial-radial arterial segment by applying a three-element windkessel model, and by using the same pressure waveforms acquired to calculate the PWV. The proposed method to determine the arterial compliance was evaluated with a physical simulation of the arterial system, where parameters were known, resulting in an estimation error of 0.73 x 10(-7) cm5 dyne(-1). In a clinical study the estimated compliance was statistically different (p < 0.01) in a controlled group ((3.12 +/- 3.53) x 10(-7) cm5 dyne(-1)) and in an SAH group ((1.04 +/- 0.74) x 10(-7) cm5 dyne(-1)). It was observed that the PWV value calculated using the maximum of the first derivative of the pressure waveform upstroke as characteristic points was the best correlated (r = -0.71) with the determined compliance. Because SAH normally results, among other causes. from a decreased arterial compliance the results suggest that the determined compliance could be used concomitantly with PWV to supply more diagnostic information about the pathogenesis of SAH.

Natural reflection site and arterial pulse wave velocity estimations based on brachial pulse wave morphology analyses

“…Instrumentation currently employed for signal acquisition and processing has been previously described [6]. The acquisition protocol has been approved by the local ethics committee, and a 50 y.o.…”

“…Initial nonrandomized studies suggesting that primary stenting was more effective in ST segment elevation myocardial infarction (STEMI) than primary PTCA [2,3] were followed by randomized trials [4][5][6][7]. A 2005 metaanalysis evaluated 9 randomized trials with a total of 4433 patients [8].…”

Three-section transmission-line arterial model for noninvasive assessment of vascular remodeling in primary hypertension

“…The system for data acquisition and analysis of the arterial pulse waveforms was developed and validated in a previous study with a hydraulic model [16]. Briefly, brachial and radial artery pressure waveforms of the right arm (at the elbow and wrist, respectively) were acquired simultaneously by piezoelectric transducers (Hewlet Packard model 21050-A) attached with elastic bands.…”

“…(6)(7)(8)(9)(10)(11) were determined for the normotensive group using the multiparametric optimization. Brachial-radial pulse wave velocity (PWVbr) was measured with the maximum of the first derivative method for at least 10 consecutive beats to minimize respiratory variations [16].…”

“…Although many studies concentrate on determining arterial compliance and/or distensibility using ultrasound data processing, arterial stiffness have also been studied using Windkessel models (Wk) [11,12,13,14,15]. However, it is well known that Wk models do not accommodate wave reflections, resulting in poor theoretical fit of diastolic phase of pressure waves [16]. Transmission-line based models can be applied to overcome limitations of the lumped Wk models, since they are able to represent transmitted and reflected waves [17].…”