EFFECT OF OUTFLOW CANNULA PLACEMENT AND PULSATILITY OF BLOOD PUMPS ON CEREBRAL BLOOD FLOW AND WALL SHEAR STRESS DURING CARDIAC ASSIST

EFFECT OF OUTFLOW CANNULA PLACEMENT AND PULSATILITY OF BLOOD PUMPS ON CEREBRAL BLOOD FLOW AND WALL SHEAR STRESS DURING CARDIAC ASSIST

Kaufmann, T. A. S.; Schmitz-Rode, T.; Moritz, A.; Steinseifer, U.

Full Article:

Device cannulation to the cardiovascular system (CVS) is an important considera-tion for cardiac assist. Some devices return blood via the ascending aorta, while others place the outflow cannula in the descending aorta. A Computational Fluid Dynamics study in de-pendency on different flow profiles representing different devices was undertaken for both approaches. The main goal was to develop a computational model to analyze the impact of different parameters of Ventricular Assist Devices (VAD) support on flow conditions in gen-eral and cerebral perfusion in particular. A 3D model of the human CVS was reconstructed from Magnetic Resonance Imaging data. A VAD outflow cannula was placed in four different positions inside ascending and proximal descending aorta. Transient numerical simulations were performed for each position assum-ing continuous and physiologically modulated device flow. The physiological flow from the heart was set to zero for a non-beating heart condition and 3 L/min for a weak heart condi-tion. Main flow variables are only slightly affected by the cannulation method but highly affected by the flow profile. Wall shear stress is increased for pulsatile support, whereby arterioscle-rotic plaque embolism might be induced. The cerebral blood flow is increased for cannulation of the descending aorta for each condition.

Device cannulation to the cardiovascular system (CVS) is an important considera-tion for cardiac assist. Some devices return blood via the ascending aorta, while others place the outflow cannula in the descending aorta. A Computational Fluid Dynamics study in de-pendency on different flow profiles representing different devices was undertaken for both approaches. The main goal was to develop a computational model to analyze the impact of different parameters of Ventricular Assist Devices (VAD) support on flow conditions in gen-eral and cerebral perfusion in particular. A 3D model of the human CVS was reconstructed from Magnetic Resonance Imaging data. A VAD outflow cannula was placed in four different positions inside ascending and proximal descending aorta. Transient numerical simulations were performed for each position assum-ing continuous and physiologically modulated device flow. The physiological flow from the heart was set to zero for a non-beating heart condition and 3 L/min for a weak heart condi-tion. Main flow variables are only slightly affected by the cannulation method but highly affected by the flow profile. Wall shear stress is increased for pulsatile support, whereby arterioscle-rotic plaque embolism might be induced. The cerebral blood flow is increased for cannulation of the descending aorta for each condition.

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DOI: 10.5151/meceng-wccm2012-18131

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Como citar:

Kaufmann, T. A. S.; Schmitz-Rode, T.; Moritz, A.; Steinseifer, U.; "EFFECT OF OUTFLOW CANNULA PLACEMENT AND PULSATILITY OF BLOOD PUMPS ON CEREBRAL BLOOD FLOW AND WALL SHEAR STRESS DURING CARDIAC ASSIST", p-822-835. In: In Proceedings of the 10th World Congress on Computational Mechanics [= Blucher Mechanical Engineering Proceedings, v. 1, n. 1]. São Paulo: Blucher, 2014.
ISSN 23580828, DOI 10.5151/meceng-wccm2012-18131