The effects of impact on the CorAide ventricular assist device.

To assess the effects of impact on the performance and durability of the CorAide ventricular assist device, three different simulations were performed. The first involved dropping a nonoperating pump onto a hardwood surface from 3.25 ft, the second and third tests by dropping from 4 and 13 ft, while the CorAide pump operated in a mock circulatory loop. The boxed pump and mock circulatory loop were dropped onto padding in three different orientations, causing loading in the following directions: radial direction, axial direction toward the secondary impeller, and axial direction toward the primary impeller. The padding thickness was adjusted and the drop height was selected so that the measured parameters were comparable with chest accelerations from published automotive test data for survivable crashes. In vitro performance testing of the pump, visual inspection, and magnetic strength of the rotating assembly were done before and after each test. No changes in pump performance or magnet strength resulted, and no pump component damage resulted from the testing.

Cleveland clinic CorAide blood pump circulatory support without anticoagulation.

The Cleveland Clinic CorAide left ventricular assist system consists of a permanently implantable centrifugal pump in which the rotating assembly is completely suspended and noncontacting. A series of chronic animal in vivo studies were conducted to evaluate the biologic effects of CorAide circulatory support without the use of anticoagulation therapy. The CorAide pump was implanted in six calves (five calves for 21 to 32 days and one calf for 95 days). The first five calves received intravenous heparin during the early postoperative periods (2-7 days). Heparin administration was then discontinued and no other anticoagulant drugs were used for the duration of the experiments. The last calf did not receive any anticoagulant except for a bolus dose of heparin (200 U/kg) during surgery. Hemodynamics were stable in all six calves, with a mean pump flow of 5.6+/-1.2 L/min and mean arterial pressure of 100+/-4 mm Hg. The blood pump surfaces were clean of thrombus in all six calves. Significant findings at autopsy were limited to one case of renal infarction. There was no incidence of mechanical failure, bleeding, or device infection. The CorAide pump can be safely run with minimal or no anticoagulant therapy.

Chronic evaluation of the Cleveland Clinic CorAide left ventricular assist system in calves.

The Cleveland Clinic CorAide left ventricular assist system is based on a third-generation, implantable, centrifugal pump in which a rotating assembly is suspended fully. To evaluate chronic in vivo system performance and biocompatibility, the CorAide blood pump was implanted in 18 calves for either 1 month or 3 months. Hemodynamics were stable in all calves with a mean pump flow of 5.9 +/- 1.2 L/min and a mean systemic arterial pressure of 98 +/- 5 mm Hg. There were no incidences of bleeding, organ dysfunction, or mechanical failure in any of the 18 calves. Hemolysis occurred in only 1 calf due to outflow graft stenosis. Thrombus inside the pump, seen in 4 of the first 6 cases, was totally eliminated by a final redesign in the remaining cases, including the last 6 implants conducted without anticoagulation therapy. The CorAide blood pump demonstrated good biocompatibility and reliable, effective system performance.