| 摘要 |
Apparatus is disclosed for mechanically assisting circulation of blood in a patient for periods of up to a week or two until the patient's heart strengthens sufficiently to take over the full workload. The circulatory assist device includes a valveless pump with a flexible bladder, a pneumatic driver for applying pressure pulses to the bladder, and a single flexible conduit for conveying blood between the patient and the pump. In use the pump and driver are mounted external to the patient's body and the flexible conduit is connected to the pump and in end-to-side relationship with a major blood vessel on that side of the heart, either right or left, which is in need of support. The circulatory assist device is operable either synchronously with the patient's heartbeat wherein the pump bladder fills as the heart ejects, then ejects in response to a pressure pulse from the driver while the heart is at rest, or asynchronously at a fixed rate if an irregular heartbeat of the patient precludes synchronous operation. The device, which can support up to about half of the workload of the heart, is easy to implant and remove and may be used to assist blood circulation in children as well as adults.
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