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:
Aug. 28, 1984
Filed:
Sep. 30, 1982
William Vollmann, Miami Lakes, FL (US);
Cordis Corporation, Miami, FL (US);
Abstract
An instruction memory for a microprocessor based cardiac pacer is equipped with code means defining improved pacing routines for accomplishing a programmably selectable 2:1 block mode in which every other atrial sense output is automatically ignored above a programmed maximum atrial rate. The 2:1 block option is preselected via the initialization routine. The atrial refractory period becomes programmable by equating it with the programmed maximum rate interval. As an alternative to 2:1 block mode, the pacer also offers VVI fallback pacing routine which can be automatically substituted for the main pacing routine. While atrial tachycardia continues to be monitored during the fallback routine, the criteria for resuming normal pacing are made different from the criteria for entering the fallback routine. In addition, before exiting the fallback routine, the R-R interval is lengthened by an amount to shift the phase of R-waves relative to P-waves. Both refractory periods and the real time clock register are adjusted by the main pacing routine to account for blanking. After any programming, normal operation is resumed by re-entering the main pacing routine as if it were at the end of a ventricular event.