Measurement, Analysis and Interpretation of Pressure/Flow Waves in Blood Vessels

Abstract

The optimal performance of the cardiovascular system, as well as the breakdown of this performance with disease, both involve complex biomechanical interactions between the heart, conduit vascular networks and microvascular beds. 'Wave analysis' refers to a group of techniques that provide valuable insight into these interactions by scrutinizing the shape of blood pressure and flow/velocity waveforms. The aim of this review paper is to provide a comprehensive introduction to wave analysis, with a focus on key concepts and practical application rather than mathematical derivations. We begin with an overview of invasive and non-invasive measurement techniques that can be used to obtain the signals required for wave analysis. We then review the most widely used wave analysis techniques-pulse wave analysis, wave separation and wave intensity analysis-and associated methods for estimating local wave speed or characteristic impedance that are required for decomposing waveforms into forward and backward wave components. This is followed by a discussion of the biomechanical phenomena that generate waves and the processes that modulate wave amplitude, both of which are critical for interpreting measured wave patterns. Finally, we provide a brief update on several emerging techniques/concepts in the wave analysis field, namely wave potential and the reservoir-excess pressure approach.

Brachial Artery “Low-Flow Mediated Constriction” Is Associated with Myocardial Perfusion Defect Severity and Mediated by an Altered Flow Pattern during Occlusion

“…Interestingly, in a previous study, an increase in retrograde flow (flow from the periphery toward the heart) and decrease in anterograde flow (flow from the heart toward the periphery) was observed during supra-systolic occlusion [7]. The increase in retrograde flow could be the result of increase in distal vascular resistance leading to impedance mismatch and therefore increase in reflected waves from the site of supra-systolic occlusion [8]. Retrograde oscillatory flow profile has been associated with endothelial dysfunction in cell culture studies [9][10][11][12].…”

Vascular Ageing in Youth: A Call to Action

“…Central systolic BP and pulse wave analysis quantify the impact of arterial properties on haemodynamics and ventriculo-vascular coupling [126,127], with parameters such as central augmentation index and reflection magnitude showing potential for improving risk stratification in adults [128,129]. Central systolic BP can be estimated from a calibrated central pulse (via carotid tonometry or ultrasound), or peripheral pulse (radial tonometry or brachial cuff volume plethysmography) and mathematical transfer function.…”

Central Pressure Waveform-Derived Indexes Obtained From Carotid and Radial Tonometry and Brachial Oscillometry in Healthy Subjects (2–84 Y): Age-, Height-, and Sex-Related Profiles and Analysis of Indexes Agreement

“…Central aortic blood pressure (aoBP) waveform contains valuable (e.g., prognostic) information beyond and in addition to the obtained from its corresponding systolic, diastolic, and pulse pressure levels (aoSBP, aoDBP, aoPP) ( Mynard et al, 2020 ). Several techniques (e.g., applanation tonometry, oscillometry/plethysmography) and mathematical methods (e.g., direct carotid or distal-arteries recordings associated to a general transfer function) have been proposed to perform waveform analyses ( Hametner and Wassertheurer, 2017 ).…”