Surgery – Truss – Pad
Patent
1990-07-02
1993-02-16
Howell, Kyle L.
Surgery
Truss
Pad
A61N 1362
Patent
active
051861690
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The invention relates to an inplantable cardiac pacemaker having a plurality of inputs for signal reception and switching means connected to the inputs.
With modern cardiac pacemakers a sequence of input signals are processed which occur at separate leads. These signals must be increased in amplitude in accordance with the signal level and if necessary must be filtered or interimly stored. For this, with the conventional cardiac pacemakers, separate input amplifiers are necessary which require a substantial construction volume and this construction volume acts contrary to the required diminshing of the outer dimensions of the implantable cardiac pacemakers. Also, in the integrated embodiment, the area covered on a silicon chip by a plurality of preamplifiers and filters is considerable. In addition, the circuits in the analog embodiment are quite complicated in comparison to digital circuits and a plurality of integrated construction elements are needed which make the additional means needed for each process channel considerable.
SUMMARY OF THE INVENTION
The object of this invention is to provide a circuit for a cardiac pacemaker which, even though the number of input channels is increased, is only slightly more complicated than the means required for just one single input channel.
The invention is based on the realization that the signals to be interpreted in the heart during signal processing with regard to the change with time require a much smaller transmission band-width than that which is supplied by the usual amplifier circuits.
Due to the time overlapping function all or nearly all of the signals relevant with regard to the operational characteristics of the cardiac pacemaker can be processed in one and the same transmission path.
A special advantage is that simultaneously with the sequential switching over between signal sources, transmission path and output connections, the transmission characteristics of the transmission path can also be switched over by switching amplification factors and/or in particular, by switching filter characteristics which is carried out by switching over the similarly synchronical switchable capacities. The switching over processes fit into the sequential clock cycle times in such a way that a switching over process of a signal path comprises differing signal paths being switched on periodically during the recurring clock cycle sequence. In addition, signals can also be transmitted for various modes of operation within a recurring clock cycle sequence so that the signals for these modes of operation with regard to the signal processing can be processed as it were "simultaneously", whereby the one signal which offers the best result is only selected in a subsequent step.
The transmission path can be used simultaneously for signal formation or for controlling during which the characteristics of the transmission path can also be altered in a controlled manner and in which a feedback occurs due to the characteristics of the lead being alterable dependent on the data transmitted via the lead, whereby in an advantageous feature the transmission path itself or else a time-sequential part of the transmission path can act as the regulation path.
In this way an optimal amplifier configuration can be achieved for implantable cardiac pacemakers. The configuration requires a minimum of external passive components and a minimal number of IC-circuits, to be able to guarantee a multiplex two chamber operation including atrial and ventricular endocardial ECG supervision and signal reception. In addition, the bipolar and unipolar operation mode is programmable and the input shut-off of the input and the sensitivity (amplification) is programmable. A multipole multiplex-bandpass-ECG-filter circuit is provided on the chip to record the R-wave and the P-wave signals.
Further advantageous features of the invention are featured in the dependent claims and will be described in greater detail below together with a description of the preferred embodiment of the i
REFERENCES:
patent: 4399820 (1983-08-01), Wirtzfeld et al.
patent: 4543955 (1985-10-01), Schroeppel
patent: 4549548 (1985-10-01), Wittkampf et al.
patent: 4628934 (1986-12-01), Pohndorf et al.
patent: 4681111 (1987-07-01), Silvian
patent: 4726379 (1988-02-01), Altman et al.
patent: 4877032 (1989-10-01), Heinze et al.
Biotronik Mess- und Therapiegerate GmbH & Co.
Howell Kyle L.
Schaetzle Kennedy J.
LandOfFree
Common signal transmission path cardiac pacemaker with switchabl does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Common signal transmission path cardiac pacemaker with switchabl, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Common signal transmission path cardiac pacemaker with switchabl will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2141544