Abstract: An esophageal stethoscope comprises a tubular flexible body having a proximal end and a closed distal end, an acoustic region defined on the body and spaced from the closed distal end. First and second spaced apart electrodes are mounted on one side of the body and between the distal end and the acoustic input region. The electrodes are spaced from each other and the distance between the mid-point of the electrodes and the acoustic input region is about 5-10 cm. A second pair of electrodes are mounted between the distal end and the first electrode pair and are manually movable laterally into engagement with the esophageal tissue.

Abstract: An improved endocardial lead for electrocardial stimulation includes a sleeve that has a face surface. A conductor fitted into the sleeve, such that a distal end of the conductor passes completely through the sleeve, past the face surface, is electrically and mechanically connected to the face surface of the sleeve by mechanical means, e.g. crimping, and/or through the application of heat, e.g. welding or brazing. An electrode is integrated with the sleeve along an outer sleeve surface. A highly reliable, redundant joint is thereby provided between the sleeve and the conductor that secures the conductor against movement and therefore minimizes stress placed on the conductor, preventing fatigue to the conductor at the joint.

Abstract: A diagnostic connector port is premolded into a header of a pulse generator device. A diagnostic connector port is attached to each of the electrical contacts in the header and does not measurably affect the system resistance. The diagnostic connector port is sealed against body fluids or other external, conductive fluids. Excellent electrical contact is achieved via a special connector pin/socket design. The diagnostic connector port is keyed for one way only insertion of the external diagnostic equipment into the diagnostic connector port.

Abstract: An electrode device for intracorporeal stimulation of body tissue, in particular for intracardial stimulation of heart tissue, has an electrode cable containing a coiled, flexible, insulated first wire running along substantially the entire length of the electrode cable and whose interior forms a channel, with at least one partially conductive electrode head provided on the distal end of the electrode cable. The cable also contains a second wire provided in the channel, this second wire running coaxially along the entire length of the electrode cable and being attached at or near the distal end of the electrode cable. The proximal end of the second wire extends beyond the proximal end of the electrode cable, a device for displacing the second wire in relation to the electrode cable in a selected way is provided so that by compressing the coiled first wire the electrode cable can be made stiff or pliant, as desired, with the need for a stylet.

Abstract: In order to be able to set a current distribution in the heart in the event of defibrillation which is optimum both spatially and temporally, a pulse-generating device is provided having n-1 outputs connected in series, to which a total of n output terminals and n electrodes are connected. The device generates output pulses at its outputs which temporally overlap one another at different times and in different numbers.

Abstract: Heart events are identified within an electrical signal derived from the heart by determining when the signals exceed a threshold which is matched to the signal height of the electrical signal dependent on a chronological average value of the detection margins of the signal that exceed the threshold in successive detection events. In order to suppress the influence of noise-like disturbing signals that appear in isolation on the control of the threshold but to nonetheless achieve an adequately fast adaptation of the threshold to rapid, substantial changes of the electrical signal despite the formation of an average value, the formation of the average value ensues over a time interval corresponding to the duration of only a few breaths and a change of the threshold ensues only when the average value respectively upwardly or downwardly transgresses upper or lower the limit values of a switching hysteresis.

Abstract: In a dual chamber pacemaker capable of stimulating the atrium and ventricle in a heart, a stimulation pulse in the atrium could be sensed as a ventricular event which cannot be distinguished from a premature ventricular contraction, so the pacemaker institutes a blanking interval in which no sensing occurs and a crosstalk interval in which sensing occurs, detections in the crosstalk interval causing the emission of a ventricular stimulation pulse with a shortened A-V interval. A dual chamber pacemaker and a method for operating same are disclosed wherein the blanking interval is optimized so as to reduce the risk of a PVC being missed and so as also to minimize the number of detected events, caused by crosstalk from the atrium, in crosstalk intervals. This is accomplished by counting, for a number of cardiac cycles, the number of detections in crosstalk intervals and forming a relationship of the count to the number of cardiac cycles.

Abstract: A cardioverter or defibrillator employing multiple electrode pairs. The device includes an output stage comprising two capacitors or capacitor banks which are connected in parallel during the discharge of the first pulse between the electrodes in one pair and are thereafter connected in series and discharged between the electrodes in a second electrode pair.

Abstract: A disposable spirometer mouthpiece comprises a resilient tubular member, having inner and outer surfaces and a defined wall thickness, the wall of the tubular member having first and second longitudinal zones of reduced thickness and thus reduced strength which allows the spirometer mouthpiece to be collapsed into a flat state for packaging and storage. Preferably, the tubular member is resilient, such that when released from a package, the resilience of the tubular member allows it to resume an essentially cylindrical shape for testing. After testing, the mouthpiece is disposed of and because of reduced zones of thickness, the mouthpiece is easily collapsed to its flat state by the weight of other waste to minimize disposal space.

Abstract: An apparatus for detecting, identifying and treating tachyarrhythmias. Tachyarrhythmias are detected and identified by the use of overlapping ranges of intervals. Provisional identification of tachyarrhythmia is accomplished by measuring and tracking intervals within two overlapping or adjacent interval ranges. Further classification and identification of tachyarrhythmias is accomplished by determining the relative numbers of intervals within a preceding series falling within a third interval range, overlapping one or both of the other interval ranges. In response to identification of the tachyarrhythmia, an appropriate therapy is selected and delivered.

Abstract: A pulse rate sensor system is packaged in a wristwatch sized assembly and is worn by the user to provide an accurate determination of pulse rate. A tonometer sensor is provided to detect heartbeat pressure waves produced by a superficial artery. A microcomputer manipulates the unprocessed tonometer sensor element signals using multiple algorithms to determine an accurate pulse rate.