Effect of anatomical variation on extracorporeal membrane oxygenation circulatory support: A computational study. (February 2022)

• Record Type: Journal Article
• Authors: Khodaee, Farhan; Nezami, Farhad R.; Zampell, Brooke A.; Galper, Eitan; Edelman, Elazer R.; Keller, Steven P.
• Is Part Of: Computers in biology and medicine. Volume 141(2022)
• Publication Date: 2022-02
• Subjects: ECMO ExtraCorporeal Membrane Oxygenation -- CFD Computational Fluid Dynamics -- MCS Mechanical circulatory support -- CTA computed tomography angiography; Extracorporeal membrane oxygenation -- Mechanical circulatory support -- Cardiogenic shock -- Computational fluid dynamics; Medicine -- Data processing -- Periodicals; Biology -- Data processing -- Periodicals; 610.285
• DOI: 10.1016/j.compbiomed.2021.105178
• Languages: English
• ISSNs: 0010-4825

Abstract

Abstract: Background: Extracorporeal membrane oxygenation (ECMO) via femoral cannulation is a vital intervention capable of rapidly restoring perfusion for patients in shock. Despite increasing use to provide circulatory support, its hemodynamic effects are poorly understood and the impact of patient-specific anatomical variation on perfusion is unknown. This study investigates the complex failing heart-mechanical circulatory support circulation and analyzes the effect of patient-specific vascular anatomical variations on hemodynamics and end-organ perfusion. Methods: Patient-specific vascular geometries were constructed from segmenting clinical computerized tomography angiography images and quantitatively compared using tortuosity, curvature, torsion, and lumen diameter. Computational fluid dynamic simulations were performed on a subset of geometries selected to represent a range of anatomical variation. Heart failure severity was modeled by varying the relative fraction of total flow provided by the heart and the extracorporeal circuit. A 3-element lumped parameter model was applied to accurately and dynamically model distal perfusion boundary conditions. Hemodynamic parameters and end-organ perfusion were analyzed and compared to assess the effect of anatomical variation. Results: Pulsatile antegrade cardiac perfusion and ECMO retrograde perfusion collide in the aorta to form a dynamic watershed region. The size, position, and variation of this region over the cardiac cycle is substantially altered by patient anatomical region. Increased vascular tortuosity reduces the proximal extent of flow from circulatory support and decreases the size of the watershed region. Conclusions: Patient vascular anatomy is a key determinant of the ECMO-failing heart circulation that alters the location and extent of the watershed region and affects the tissues at risk for differential hypoxia and circuit-derived thromboemboli for a given level of support. Highlights: Computational fluid dynamics analysis of the failing heart:ECMO circulation using patient-specific vascular anatomies. The size, location, and movement of the complex watershed region is altered by patient anatomy. Tortuous anatomy of the femoral and iliac arteries results moves the watershed region distally within the aorta.