Student name:
Tomer Meirson
Department:
Medical Engineering
Advisor name:
Dr. Idit Avrahami &
Dr. Gil Bolotin
Research Project Numerical Analysis of Flow in
Coronary Artery Bypass Graft
תערוכת
פרויקטי
גמר
2013 1
Figure 5: Wall Shear Stress distribution for unsupported grafts (A,B,C) and Supported grafts
(D,E,F) at diastole (t=1.5 sec)
RESULTS
•
The wall shear stress analysis resulted in low stresses at the dilatation areas of the unsupported grafts
compared to supported grafts, with higher and more uniform stress distribution (fig. 5). Elevated stresses
were also found in the unsupported grafts at luminal irregularities.
•
The supported grafts has improved WSS at regions with minimal stresses, with higher values of up to 1000%,
compared to unsupported grafts (fig. 6).
•
The results show disturbed flow with vortexes at unsupported graft C (fig. 7). No vortexes or disturbed flow
was found on any of the supported grafts.
•
The full results, including stress analysis which is presented in the project report, support the conclusions of
the fluid part as well.
•
These findings suggest that constricted graft with EMS improves hemodynamic factors that are involved in
intimal hyperplasia.
CONCLUSIONS
•
In order to improve patency rates and decrease graft failure following CABG surgery procedure, the
leading causes of intimal hyperplasia should be treated. This investigation helps to understand and
establish the advantages of the external mesh support and to evaluate the effects of the external support
on the leading causes of graft failure.
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Figure 6: Time dependent WSS at
the region with the lowest
stresses of each model
Figure 7: Velocity vectors at dilatations of
unsupported graft C (up: t=1 sec, down: t=0.5 sec)
268...,224,225,226,227,228,229,230,231,232,233 213,214,215,216,217,218,219,220,221,222,...1