Abstract 20526: Computational Fluid Dynamics in Partial Mechanical Circulatory Support: Implications for Patient Care
Introduction: Partial mechanical circulatory support (pMCS) is used for the therapy of heart failure. The CircuLite® Pump has been introduced clinically with its inflow cannula connected to the left atrium and the outflow cannula to the right subclavian artery. Aim of our study was to visualize and quantify flow patterns using computational fluid dynamics (CFD) in CT angiography (CTA).
Methods: Two heart failure patients with pMCS were imaged with ECG-gated CTA and echocardiography. CFD was performed in 3D derived from CTA using flow boundary conditions measured with ultrasound. Flow was visualized using velocity vectors of blood flow. Average velocity was calculated at 10 time points during cardiac cycle in the aorta and the innominate. Wall shear stress (WSS) was visualized on the wall of the digital model.
Results: Flow reversal was observed in mid-systole for both cases distal from the origin of the innominate artery in both cases due to asynchrony of the constant flow of the device with the pulsatile flow of the heart (fig.). Maximum velocity of this back flow was 0.39 m/s in case 1 and 0.2 m/s in case 2. Therefore, further distal in the innominate artery, a region of slow and stagnant flow with low WSS at the artery wall was observed which changed during cardiac cycle.
Conclusions: CFD analysis revealed an asynchronous behavior in the inducted flow patterns during systole. Further design should allow for synchronization with the native heart function.
Figure: On top flow during systole for both cases (case 1 on left), below flow during diastole. WSS is shown in pseudo-color representation with red indicating high values. Flow is visualized by arrows. During systole, a region of low WSS (blue) exists in the innominate artery which is absent during systole indicating flow reversal at this location.
Bottom panel: Velocity in inferior-superior direction during cardiac cycle for both cases. Red lines demonstrates change of direction of flow in the innominate during systole.
Author Disclosures: S. Partovi: None. C. Karmonik: None. F. Rengier: None. M. Mueller-Eschner: None. H. Meredig: None. H. Kauczor: None. R. Arif: None. B. Schmack: None. M. Karck: None. A. Ruhparwar: None.
- © 2014 by American Heart Association, Inc.