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:
May. 12, 2009
Filed:
Feb. 22, 2005
Dirk Mussig, West Linn, OR (US);
Volker Lang, West Linn, OR (US);
Jie Lian, Beaverton, OR (US);
Biotronik CRM Patent AG, , DE;
Abstract
An implantable cardiac device is provided for adaptive ventricular rate smoothing during atrial fibrillation (AF). When AF is detected, the operation of the device is switched to non-atrial synchronized pacing mode such as DDI, DDIR, VDI, VDIR, VVI, or VVIR. The ventricular escape interval (VEI) is beat-by-beat modulated around a physiological interval zone (PIZ), which is determined by the pre-arrhythmia ventricular rate or the output of rate responsive sensor. The VEI remains unchanged if the preceding ventricular event is sensed and its RR interval is within the PIZ. Otherwise, the VEI is decreased asymptotically toward a lower interval threshold if the preceding RR interval is longer than the upper limit of the PIZ, or the VEI is increased asymptotically toward an upper interval threshold if the preceding RR interval is shorter than the upper limit of the PIZ. The step of incrementing or decrementing the VEI is adaptive to the absolute difference value between the preceding RR interval and the asymptotic interval threshold to ensure fast recovery of deviant RR interval toward the PIZ and to reduce the amount of high rate ventricular paces after a ventricular sense with very short coupling interval.