Pressure drop and arterial compliance – Two arterial parameters in one measurement

• Published in: Journal of biomechanics Vol. 50; pp. 130 - 137
• Main Authors: Rotman, Oren M, Zaretsky, Uri, Shitzer, Avraham, Einav, Shmuel
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 04-01-2017; Elsevier Limited
• Subjects: Accuracy; Acute coronary syndromes; Algorithms; Angiography; Arterial distensibility; Arteriosclerosis; Atherosclerosis; Average velocity; Biomechanics; Blood Flow Velocity; Blood Pressure; Boundary conditions; Cardiovascular disease; Catheterization; Catheters; Compliance; Computer applications; Convergence; Coronary; Coronary artery; Coronary Stenosis - diagnosis; Coronary Stenosis - pathology; Coronary Stenosis - physiopathology; Coronary vessels; Coronary Vessels - pathology; Coronary Vessels - physiopathology; Data processing; Decision making; Density; Differential pressure; Distilled water; Elastic properties; Feasibility studies; Fluid flow; Fluid-structure interaction; Fractional flow reserve; Glycerol; Heart diseases; Heterogeneity; Humans; Hyperemia; Implants; Indicators; Intubation; Ischemia; Laminar flow; Lesions; Mathematical models; Mechanical properties; Medical imaging; Medical instruments; Models, Cardiovascular; Motivation; Parameters; Physical Medicine and Rehabilitation; Pressure dependence; Pressure drop; Pressure measurement; Real time; Scaling; Stents; Stress; Stroke; Temperature effects; Turbulence; Turbulence models; Ultrasound; Velocity; Viscosity; Vulnerable plaque; P d -max; ρ; B; σ; engineering stress [Pa]; K; CFR; ϑ; stretch; Vulnerable plaque; FFR; Re; maximum component of P d ( t) for a single cycle [mmHg]; B.C; Atherosclerosis; Coronary; P d - mean; average component of P d ( t) for a single cycle [mmHg]; boundary conditions; FSI; fractional flow reserve; time-dependent pressure drop [mmHg]; Reynolds number; P d ( t); CMP; P g ( t); density [kg/m 3]; fluid–structure interaction; common mode pressure; fluid dynamic viscosity [Pa s]; coronary flow reserve; time-dependent Gauge pressure (blood pressure) [mmHg]; µ; Poisson ratio; fluid bulk modulus of elasticity [Pa]; λ; Arterial distensibility; solid bulk modulus of elasticity [Pa]; Fractional flow reserve; Pg(t); Pd-max; Pd-mean; Pd(t)
• ISSN: 0021-9290; 1873-2380
• DOI: 10.1016/j.jbiomech.2016.11.026

Abstract Coronary artery pressure-drop and distensibility (compliance) are two major, seemingly unrelated, parameters in the cardiovascular clinical setting, which are indicative of coronary arteries patency and atherosclerosis severity. While pressure drop is related to flow, and therefore serves as a functional indicator of a stenosis severity, the arterial distensibility is indicative of the arterial stiffness, and hence the arterial wall composition. In the present study, we hypothesized that local pressure drops are dependent on the arterial distensibility, and hence can provide information on both indices. The clinical significance is that a single measurement of pressure drop could potentially provide both functional and bio-mechanical metrics of lesions, and thus assist in real-time decision making prior to stenting. The goal of the current study was to set the basis for understanding this relationship, and define the accuracy and sensitivity required from the pressure measurement system. The investigation was performed using numerical fluid–structure interaction (FSI) simulations, validated experimentally using our high accuracy differential pressure measurement system. Simplified silicone mock coronary arteries with zero to intermediate size stenoses were used, and various combinations of arterial distensibility, diameter, and flow rate were simulated. Results of hyperemic flow cases were also compared to fractional flow reserve (FFR). The results indicate the potential clinical superiority of a high accuracy pressure drop-based parameter over FFR, by: (i) being more lesion-specific, (ii) the possibility to circumvent the FFR dependency on pharmacologically-induced hyperemia, and, (iii) by providing both functional and biomechanical lesion-specific information.