Article

In vivo validation of a one-dimensional finite-element method for predicting blood flow in cardiovascular bypass grafts.

Department of Mechanical Engineering, Stanford University, 1201 Welch Road, Room P224, Stanford, CA 94305-5464, USA.
IEEE Transactions on Biomedical Engineering (impact factor: 2.28). 07/2003; 50(6):649-56. DOI:10.1109/TBME.2003.812201 pp.649-56
Source: PubMed

ABSTRACT Current practice in vascular surgery utilizes only diagnostic and empirical data to plan treatments and does not enable quantitative a priori prediction of the outcomes of interventions. We have previously described a new approach to vascular surgery planning based on solving the governing equations of blood flow in patient-specific models. A one-dimensional finite-element method was used to simulate blood flow in eight porcine thoraco-thoraco aortic bypass models. The predicted flow rate was compared to in vivo data obtained using cine phase-contrast magnet resonance imaging. The mean absolute difference between computed and measured flow distribution in the stenosed aorta was found to be 4.2% with the maximum difference of 10.6% anda minimum difference of 0.4%. Furthermore, the sensitivity of the flow rate and distribution with respect to stenosis and branch losses were quantified.

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Keywords

10.6% anda minimum difference
 
blood flow
 
branch losses
 
cine phase-contrast magnet resonance imaging
 
Current practice
 
maximum difference
 
mean absolute difference
 
one-dimensional finite-element method
 
porcine thoraco-thoraco aortic bypass models
 
predicted flow rate
 
quantitative
 
simulate blood flow
 
stenosis
 
vascular surgery utilizes