| 摘要 |
A closed chest intra-aortic balloon catheter based ventricular assist device comprising an intra-aortic balloon (IAB) catheter and a pumping chamber having a smaller diameter portion and a more proximal larger diameter portion. The IAB catheter balloon membrane is disposed within the larger diameter portion. The entire device is inserted percutaneously into the aorta of a patient such that the tip of the IAB catheter is just distal to the left subclavian artery and the distal end of the smaller diameter portion is in the left ventricle. The smaller diameter portion has an intake valve at its distal end which acts as a one-way valve allowing blood to flow into the lumen of the pumping chamber but not out of it. The pumping chamber has one or more outlet valves. As the balloon membrane deflates, pressure in the pumping chamber drops below that in the left ventricle, and as a result, blood flows into the pumping chamber. As the balloon membrane inflates, increased pressure in the pumping chamber forces the intake valve shut and forces blood through the outlet valves into the aorta. The pumping chamber becomes substantially rigid after insertion so as to withstand arterial blood pressure. |
