A Novel Experimental Method to Estimate Stress-Strain Behavior of Intact Coronary Arteries Using Intravascular Ultrasound (IVUS)

Abstract

Most arterial mechanics studies have focused on excised non-coronary vessels, with few studies validating the application of ex-vivo results to in-vivo conditions. A method was developed for testing the mechanical properties of intact left anterior descending coronary arteries under a variety of conditions. Vascular deformation and pressure were simultaneously measured with intravascular ultrasound and a pressure transducer guidewire, respectively. Results suggest the importance of understanding in-vivo factors such as myocardial support, vascular tone and local pressure fluctuations when applying ex-vivo coronary characterization data. With further development, this method can more accurately characterize the true in-vivo constitutive behavior in normal and atherosclerotic coronaries.

Modular polymer design to regulate phenotype and oxidative response of human coronary artery cells for potential stent coating applications

“…We believe that increased surface charge stimulates outside-in production of O 2 •− , resulting in an abundance of intracellular O 2 •− . Because intracellular O 2 •− promotes HCASMCs proliferation and HCASMCs are normally quiescent, more compliant substrates likely resemble a pathophysiological environment resulting from outward vascular remodeling that promotes proliferation, such as that found in atherosclerosis [35, 36]. For interactions with HCASMCs, 4%PEG-96%PCL was the best substrate because of its moderate surface charge and mechanical properties, as well as promotion of a balanced ROS production.…”

Impact of age and hyperglycemia on the mechanical behavior of intact human coronary arteries: an ex vivo intravascular ultrasound study

“…The tissue bath containing PBS was kept at 37 Ϯ 1°C to reproduce in vivo conditions. Luminal pressure was altered with a computer-controlled pump system, as described previously (30). To measure intraluminal variations accurately, a pressure-sensing guidewire (Pressurewire, RADI Medical Systems) was calibrated and inserted proximally into the mounted vessel.…”

Elastomechanical properties of bovine veins

“…Debes and Fung (1995) first proposed a preconditioning of very low frequency cyclic loading for a few cycles, suggesting that the internal structure of the tissue would respond to this loading until it reached a steady state that would allow consistent mechanical response to loading. Obtaining elastomechanical properties via in vivo techniques using ultrasound as initially proposed by Chapman and Charlesworth (1983) has since been refined by Lehmann et al (1993) and others, and recently extended by Tajaddini et al (2003).…”