Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Dual chamber pacemaker system and method with improved switching between synchronous and asyncrhonous behavior










Image Number 2 for United States Patent #5531771.

A dual chamber pacemaker system having a dynamic tracking limit, as well as a dynamic pacing limit (flywheel rate), the two dynamic limits being normally coupled to a measure of the sensed atrial rate as long as such rate is physiological. When the atrial signal is lost, i.e., cannot be tracked, the pacemaker responds with asynchronous pacing and normally decrements both dynamic limits, taking the flywheel rate down toward a lower pacing limit. The pacemaker of this invention provides a freeze function whereby the dynamic pacing limit and dynamic tracking limit are maintained constant for a plurality of cycles following asynchronous operation, to improve the possibility of regaining tracking if an underlying physiological atrial signal reappears at about the rate prior to being lost. The freeze function may be timed out for a predetermined number of cycles, e.g., eight, or may have a reduced duration if a series of consecutive synchronous cycles is detected. In a second embodiment, the dynamic tracking limit is decreased without any freeze when the pacer goes into asynchronous operation, but the dynamic tracking limit which existed just before the switch to asynchronous operation is remembered; if the atrial rate reappears below this remembered dynamic tracking limit, the dynamic tracking limit is ramped upward to achieve quick tracking of the reappeared sinus rate. A further embodiment may incorporate the features of the first two embodiments, i.e., a short freeze followed by a period of remembering the value of DTL when async mode was initiated.








 
 
  Recently Added Patents
Method for producing coated steel sheet
In-vehicle electronic control apparatus having monitoring control circuit
Use of deuterium oxide for the treatment of virus-based diseases of the respiratory tract
Method and apparatus for detecting an intermittent path to a storage system
Reconstruction of deforming surfaces by canceling ambient occlusion and refining 3-D shape
Power management method for reducing power of host when turning off main monitor and computer system applying the same
Data unit receiver and sender control method
  Randomly Featured Patents
Foldable pet crate
Beverage serving stand
Device for machining by electroerosion
Degasifier
Ergonomic and space-saving arrangement of monuments underneath a rest compartment in an aircraft
Boiler tube welding clamp
Synchrotilt chair
Electronic device with connector module
Dentifrices
Method and arrangement for variably generating cryptographic securities in a host device