einstellmechanismus for herzschrittmacherrate, with the use of a magnetic coupling

摘要

There is disclosed a pacer rate adjustment mechanism which utilizes magnetic coupling. In one embodiment of the invention, a diametrically magnetized disc magnet, mounted on a bearing, is fixed to the shaft of a small rate-controlling potentiometer in the pacer. The pacer rate can be adjusted by rotating a strong bar magnet external of the patient, thereby rotating the pacer magnet and turning the potentiometer shaft; continuous rate adjustment is possible without requiring skin puncture. In another embodiment of the invention, two flux-linked diametrically magnetized disc magnets are provided in the pacer. One of them is fixed to the potentiometer shaft and the other is connected to a needle port. The latter magnet is turned by use of a Keith or other needle extended through the skin of the patient; the turning of this magnet causes the potentiometer magnet to rotate and the pacer rate to be varied. Although this embodiment of the invention requires skin puncture to change the pacer rate, it still offers one of the main advantages of the first embodiment, namely, a total hermetic seal with no possibility of fluid penetration into the pacer circuit itself. This is accomplished by mounting the needle magnet external of the enclosure in which the circuitry is potted, and then covering the external magnet and needle port with the conventional epoxy coating and/or silicone rubber boot.