The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 25, 1978
Filed:
Apr. 21, 1977
Robert Lee Cannon, III, Waltham, MA (US);
American Optical Corporation, Southbridge, MA (US);
Abstract
In an implanted heart stimulating device of the demand type, test mode circuitry is arranged to cause the temporary generation of stimulation impulses at the demand-rate in the presence of naturally occurring heartbeats. The test mode circuitry may cause dependence of the heart-stimulation rate upon the level of the power source within the test mode or at least a portion of the test mode, but is arranged to provide a heart-stimulation rate independent of the level of the power source in the ordinary demand mode. The test mode circuitry is operative, through a relatively simple bias-modifying circuit, to force the pacer to generate at least several stimulating impulses at the demand-rate immediately following cessation of that portion of the test mode in which stimulation impulses are generated at a rate dependent upon the level of the power source. Subsequently, the pacer reverts to the ordinary (i.e., non-forced) demand mode.