Effect of anatomical variation on extracorporeal membrane oxygenation circulatory support: A computational study

Farhan Khodaee; Farhad R Nezami; Brooke A Zampell; Eitan Galper; Elazer R Edelman; Steven P Keller

doi:10.1016/j.compbiomed.2021.105178

Effect of anatomical variation on extracorporeal membrane oxygenation circulatory support: A computational study

Comput Biol Med. 2022 Feb:141:105178. doi: 10.1016/j.compbiomed.2021.105178. Epub 2021 Dec 30.

Authors

Farhan Khodaee¹, Farhad R Nezami², Brooke A Zampell³, Eitan Galper⁴, Elazer R Edelman⁵, Steven P Keller⁶

Affiliations

¹ Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
² Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Surgery (Thoracic and Cardiac Surgery), Brigham and Women's Hospital, Boston, MA, USA.
³ Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
⁴ Department of Mechanical Engineering, University of Maryland, College Park, MD, USA.
⁵ Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Medicine (Cardiovascular Medicine), Brigham and Women's Hospital, Boston, MA, USA.
⁶ Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Medicine (Pulmonary and Critical Care Medicine), Johns Hopkins Hospital, Baltimore, MD, USA. Electronic address: steven.keller@jhmi.edu.

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.

Keywords: Cardiogenic shock; Computational fluid dynamics; Extracorporeal membrane oxygenation; Mechanical circulatory support.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Aorta
Extracorporeal Membrane Oxygenation* / methods
Heart Failure* / diagnostic imaging
Heart Failure* / therapy
Hemodynamics
Humans
Pulsatile Flow

Abstract

Publication types

MeSH terms

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