Artificial Circulatory Model for Analysis of Human and Artificial Vessels

Abstract

Abstract:Background: Ex vivo computer controlled circulatory reactors are advantageous for the investigation of circulatory systems. So far, most of the models have dealt with laminar or pulsatile flow. This study aimed to monitor blood vessel and vessel graft compliance continuously under physiological flow in real time. Methods: Human common iliac arteries and silicon tubes served as interposition grafts. Changes in wall diameter and displacement were analyzed. The artificial circulatory system (ACM) presented an "artificial heart" able to simulate various ejection pressures, ejection volumes (EV), and frequencies of pulsation (FP). ACM was validated by comparing medical data reconstructed with the 2D-speckle-tracking-technique (2DSTT). Results: Silicon tubes were more rigid compared to iliac arteries, as changes in diameter were approximately 48% lower (0.56 ± 0.007 mm vs. 0.83 ± 0.016 mm, p < 0.0001, for EV = 70 mL and FP = 60 min −1 ). Wall displacement was 2.3-fold less pronounced in silicon tubes (1.45 ± 0.032 mm vs. 5.79 ± 0.043 mm for iliac arteries (p < 0.0001)). FP and EV did not further increase differences in wall displacement between both types of grafts. There were no significant changes between results gathered from ACM and 2DSTT. Conclusions: The ACM was successfully validated by 2DSTT with the use of selected grafts. It may become a useful tool to investigate different types of vascular grafts.

Spatial Configuration of Abdominal Aortic Aneurysm Analysis as a Useful Tool for the Estimation of Stent-Graft Migration

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Hazards associated with municipal waste storage. Vol. I

“…After extraction, the organic layer was separated and the samples were extracted again with dichloromethane (10 cm 3 dichloromethane /200 cm 3 sample) [29][30][31]. Due to the formation of emulsions, the separation of the aqueous and organic phase was slow, centrifugation was carried out (2,500 x g, 10 min) to fully separate the phases [32][33][34][35]. The organic fraction was concentrated (ca.…”

Feasibility and accuracy of a novel automated three-dimensional ultrasonographic analysis system for abdominal aortic aneurysm: comparison with two-dimensional ultrasonography and computed tomography

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