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:
Feb. 08, 1994
Filed:
Feb. 27, 1992
Richard Sutton, London, GB;
Ivan Bourgeois, Verviers, BE;
Medtronic, Inc., Minneapolis, MN (US);
Abstract
A pacemaker having a hysteresis feature which permits intrinsic heart activity, controlled by the sinus node to resume optimally after pacing. The pacemaker has a programmable lower rate and upper rate, a programmable lower hysteresis rate (LRH) corresponding to a lower rate hysteresis interval (LRHI), and a programmable rate (IR) intermediate an upper pacing rate (UR) and a lower pacing rate (LR). A microprocessor measures the average rate of change M.sub.AVG in the intervals between consecutive ventricular depolarizations, and compares the last intrinsic escape interval RR.sub.N to the lower rate hysteresis interval (LRHI). If the last intrinsic escape interval RR.sub.N is longer than the lower rate hysteresis interval (LRHI), and if the value of M.sub.AVG is greater than a first preselected value SL.sub.1 but less than a second preselected value SL.sub.2, the pacemaker stimulates at the lower rate hysteresis (LRH) and thereafter gradually increases the pacing rate up to the intermediate rate (IR). A time counter maintains a continuous pacing at the intermediate rate (IR) for a predefined period of time, and the pacing rate is gradually decreased toward the lower pacing rate (LR).