The use of diameter distension waveforms as an alternative for tonometric pressure to assess carotid blood pressure

Abstract

Proper non-invasive assessment of carotid artery pressure ideally uses waveforms recorded at two anatomical locations: the brachial and the carotid artery. Calibrated diameter distension waveforms could provide a more widely applicable alternative for local arterial pressure assessment than applanation tonometry. This approach might be of particular use at the brachial artery, where the feasibility of a reliable tonometric measurement has been questioned. The aim of this study was to evaluate an approach based on distension waveforms obtained at the brachial and carotid arteries. This approach will be compared to traditional pulse pressures obtained through tonometry at both the carotid and brachial arteries (used as a reference) and the more recently proposed approach of combining tonometric readings at the brachial artery with linearly or exponentially calibrated distension curves at the carotid artery. Local brachial and carotid diameter distension and tonometry waveforms were recorded in 148 subjects (119 women; aged 19-59 years). The morphology of the waveforms was compared by the form factor and the root-mean-squared error. The difference between the reference carotid PP and the PP obtained from brachial and carotid distension waveforms was smaller (0.9 (4.9) mmHg or 2.3%) than the difference between the reference carotid PP and the estimates obtained using a tonometric and a distension waveform (-4.8 (2.5) mmHg for the approach using brachial tonometry and linearly scaled carotid distension, and 2.7 (6.8) mmHg when using exponentially scaled carotid distension waves). We therefore recommend to stick to one technique on both the brachial and the carotid artery, either tonometry or distension, when assessing carotid blood pressure non-invasively.

An automatic method for arterial pulse waveform recognition using KNN and SVM classifiers

“…In fact, this set was acquired at the hospital and therefore was comprised of signals provided from both patients and healthy subjects. The relevant results obtained using wavelet features confirm which was concluded in previous studies [14,26,39]. The wavelet decomposition allows the study of the detailed waveform structure [14].…”

“…Two mother wavelets (Haar and Db4) were tested, and the relative power of the reconstructed signal detail (one to four) was determined [14,26,39]. The choice of the mother wavelet depends on the application, and, generally, a wavelet similar in shape to the analysed signal is considered appropriate.…”

Central Aortic Blood Pressure From Ultrasound Wall-Tracking of the Carotid Artery in Children

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“…6 However, noninvasive estimates of cSBP have not been validated in children, and there is limited information on the magnitude of SBP amplification in children. 7,8 The aim of the study was to (i) compare estimates of central aortic systolic pressure obtained from radiofrequency ultrasound wall tracking of the carotid artery 9,10 with that measured directly using a pressure-tipped catheter placed in the aortic root at the time of arterial cannulation; (ii) to compare the values of cSBP obtained from noninvasive radiofrequency ultrasound wall tracking of the carotid artery with those obtained using applanation tonometry at the radial artery and a radialto-aortic transfer function 1 ; (iii) to determine typical SBP amplification in children with and without chronic kidney disease (CKD) and hypertension.…”

Decreased Arterial Elasticity in Children With Nondialysis Chronic Kidney Disease Is Related to Blood Pressure and Not to Glomerular Filtration Rate

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