Characterization of Calcified Plaques Retrieved From Occluded Arteries and Comparison With Potential Artificial Analogues

Abstract

Cardiovascular disease is the leading cause of death worldwide. This disease includes chronic total occlusion (CTO), which is a complete blockage of an artery. Unlike partial occlusions, CTOs are difficult to cross percutaneously using conventional guidewires (thin and flexible wires) because of the fibrotic and calcified nature of the blockage. The lack of data regarding the mechanical properties of CTO limits the development of new technologies in the field of percutaneous coronary intervention (PCI) and percutaneous peripheral intervention (PPI). In this study, calcified plaques retrieved from occluded arteries are analyzed in order to better understand their mechanical properties and to help propose an artificial analogue. Calcified plaques samples were collected from the superficial femoral artery wall within one hour following a lower limb amputation surgery. These samples were studied to determine their composition and mechanical properties. The same characterization procedures were performed on various potential artificial analogues. These analogues include three plaster materials and dense hydroxyapatite blocks. The results were then compared with those of the calcified plaques in order to determine the more favorable analogue. This mechanical analysis and the proposal of a potential analogue for the calcified plaques found in occluded arteries could benefit the development of new technologies and devices in the field PCI and PPI.

Tissue mimicking materials for imaging and therapy phantoms: a review

“…Mechanical properties of seven common types of human tissues from prior studies. Data taken from (a) Taylor and Miller (2004) Schoenfeld et al (1974) and (p) Riel et al (2014).…”

“…To fabricate phantoms with different elastic modulus, softener was added and resulted in elastic modulus of 3-200 kPa (Hungr et al 2012). The mechanical and imaging properties of Hollensteiner et al (2017Hollensteiner et al ( , 2018Hollensteiner et al ( , 2019, (g) Tai et al (2015Tai et al ( , 2016Tai et al ( , 2018, (h) Riel et al (2014), Lyu et al (2019).…”

“…Another TMM for hard tissue is the calcified plaque analog used for research in percutaneous interventions to open narrowed blood vessels. Riel et al (2014) used plaster to mold an analog and it demonstrated a similar Young's modulus (15 GPa), compressive strength (36 MPa), and porosity to those of human calcified plaque. Such calcified plaque analog has been used to study the plaque grinding in atherectomy (Lyu et al 2019).…”

Finite element analysis of cutting balloon expansion in a calcified artery model of circular angle 180°: Effects of balloon-to-diameter ratio and number of blades facing calcification on potential calcification fracturing and perforation reduction

“…where I 1 and I 2 are the first and second invariants of the Cauchy-Green tensor and a 10 and a 01 are the hyperelastic constants of 18.90 kPa and 2.75 kPa referenced from the experimental data of human femoral artery [22]. A nanoindentation study showed that the elastic modulus of human calcified plaques collected from the superficial femoral artery wall was 20.1 GPa [23].…”

FEM Simulation of Subintimal Angioplasty for the Treatment of Chronic Total Occlusions

“…The highly complex and spatially variable structure of a CTO may also change depending on lesion age. Unfortunately, assessing in vivo morphology and composition of the CTO in fully occluded blood vessels is difficult [17] and only Mathematical Problems in Engineering 3 limited information is available from ex vivo experimental observation [18]. Particularly concerning human studies, a systematic investigation regarding the mechanical behavior and failure properties of CTOs is still lacking.…”