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David J Fischer: Programmable demand pacer. Cardiac Pacemakers, Orrin M Haugen, Thomas J Nikolai, December 8, 1981: US04304238 (21 worldwide citation)

An implantable demand-inhibit type cardiac pacer for producing artificial stimulating pulses of a desired repetition rate and of a desired pulse width in the absence of normal R-wave activity in the patient's heart. The pacer is implemented principally from integrated circuit digital logic component ...


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Programmable demand pacer. Cardiac Pacemakers, December 17, 1980: GB2048688-A

An implantable R-wave inhibited cardiac pacer has integrated digital logic circuits including programmable registers 12, 16 (210, 262, Fig 4) to determine the pulse rate and width. A 5-3-4 code applied by an external pulsed electromagnet to a reed switch 20 (400, Fig.5) unlocks a digital lock 18 so ...