Abstract: An apparatus for sensing the difference between a polar fluid and a non-polar fluid includes a control assembly, a probe assembly and a conduit electrically coupling the probe assembly to the control assembly at a remote location thereto. The probe assembly includes a float, at least one fluid sensor mounted beneath the float, a fluid sensor circuit for providing a signal indicative of the polar characteristics of the fluid, and a logic circuit having a first state when the signal indicates a polar fluid and a second state when the signal indicates a non-polar fluid. The control assembly includes circuitry responsive to the state of the logic circuit for controlling alarms, visual indicators, and machine operations. The probe assembly may also include a detector for detecting the state of the fluid. If the fluid has a non-liquid state then the logic circuit has a third state which indicates the non-liquid state of the fluid.

Abstract: A motor driven rotatable camstack includes at least two cams. A V-shaped electrical terminal blade spans the two cams. Each leg of the V-shaped electrical terminal includes a cam follower which individually engages one of the cams. Two individual spring electrical contact blades are positioned on one side of the cams to cooperate with one leg of the V-shaped electrical terminal and a single spring electrical contact blade is positioned on the other side of the V-shaped terminal to cooperate with the other leg.

Abstract: A bussing block has wafers stacked one on top of the other and includes apertures which are in alignment with each other. Buss bars are carried on the wafers and have apertures aligned with the apertures in the wafers. Electrically insulating collars extend from selected ones of the wafer apertures so that when electrical terminals are inserted through all of the aligned apertures of the wafers and buss bars, the electrical terminals will be electrically isolated from the buss bars by the collars.

Abstract: A transvenous pacing lead suitable for chronic implantation having structure which permits dispensing of drugs or other chemical agents from the ring tip electrode upon physician discretion from implant through chronic implantation. A bipolar, tined endocardial ventricular lead has a plurality of small apertures within the ring tip electrode which are connected by a tube within the lead body to a bladder at the proximal end of the lead. The bladder is detachable to permit a stylet to be passed through the tube to guide the lead during implantation. A reed valve at the distal end of the tube prevents body fluid from entering the tube. A stylet restraint prevents the stylet from damaging the reed valve during implant.

Abstract: Epicardial pacing lead for affixation to epicardial heart tissue either onto the forward facing portion of the heart or behind the heart during thoracic surgery. A stylet controls a helical fixation screw in an electrode head of the pacing lead in that the stylet is turned thereby advancing the helical fixation screw beyond the planar surface of the electrode head. The epicardial pacing lead includes two embodiments which can be used in the unipolar mode of operation and one embodiment which can be used in the bipolar or unipolar mode of operation. The epicardial pacing lead requires no special tools and can be applied to the epicardial tissue with the use of surgical forceps or clamps. The pacing lead can be connected to a pulse generator located adjacent to the epicardial tissue under the skin and can be used for atrial or ventricular pacing.

Abstract: A hand-held electronic instrument to be used for timing target vehicles. The instrument has the ability to determine a comparison time-speed number by multiplication of a known speed of a setup vehicle by the length of time the setup vehicle takes to travel between two selected fixed points. The instrument has a memory for storing a comparison time-speed number, a timer, a manually operated first-fixed-point switch, a manually operated second-fixed-point switch, a divide circuit and a speed readout display. The first-fixed-point switch is pressed to start the timer when a target vehicle passes the first fixed point. When the target vehicle passes the second fixed point the second-fixed-point switch is pressed which stops the timer, and causes the instrument to divide the comparison time speed number by the output of the timer and to display the resulting speed.

Abstract: A temporary lead for pacing or monitoring purposes with insertion tool. The temporary lead is thin and lightweight having an electrical connector at a proximal end and an electrode at a distal end. A length of surgical thread is permanently attached to the electrode. A helix is molded into the surgical thread at a short distance from the electrode. A curved needle is permanently attached to the surgical thread. The curved needle is inserted into a first location of the tissue manually or using the disclosed tool which provides insertion at a fixed depth. The curved needle exits the tissue at a second location. The curved needle and surgical thread are pulled from the second location thus bringing the electrode into sufficient contact with the tissue. The helix is elongated under the stress of tension supplied to pull the electrode into position. The excess surgical thread is cut at the second location, removing the tension.

Abstract: An electrode system for recording neural signals suitable for chronic implantation employing shielding and other techniques to improve signal-to-noise ratio. Three electrically isolated electrodes are used in a tripolar fashion. The electrodes are thin wires which are coated with a conductive gel. Each electrode is wrapped around the nerve trunk and held in place by a dielectric encapsulant. A shielding flap is wrapped about the assembly. The electrodes are coupled to conductors that travel through a shielded tube to the sensing electronics. The shield of the tube is electrically coupled to the shielding flap.

Abstract: A synthetic leaflet aortic and mitral heart valve for use in replacement of diseased natural heart valves having a flexible, curved framework, a flexible membrane attached to the framework and fixation means for attaching the valve to the tissue annulus. The framework consists of at least three curved flexible valve struts, each joined together at one end to a common central point of the valve and extending in the same direction radially at equal angles so that the free ends are unattached and at a distance from one another. The free ends are provided with sewing pads for artificial attachment of each free end separately to the natural tissue annulus or to an artificial annulus reconstruction ring which itself is sutured to the tissue annulus to restore its symmetry.

Abstract: A lead or heart wire for use in temporary electrical stimulation or monitoring of epicardial tissue. Positive fixation is accomplished by suturing the electrode to the tissue using an attached length of surgical thread and a curved needle. The heart wire is a tightly wound helix of wire insulated by a sheath. A needle, used for electrical connection to external equipment, is attached to the proximal end. Near the distal end, the conductor is bent into an "C" shape. The electrode is attached about midway along the top of the "C" shaped length of conductor. The length of surgical thread is attached to the proximal end of the conductor and exits the sheath through an aperture proximal to the "C" shape. The curved needle is attached to the distal end of the surgical thread. The heart wire may be readily removed after use by removing the surgical thread. The heart wire may be readily removed after use by removing the surgical thread, which is retracted into the conductor by pulling at its proximal end.

Abstract: Ring electrode for a bipolar pacing lead where the ring electrode is secured to an outer coiled conductor by swaging the outer coiled conductor between the ring electrode and a swaging core where the distal end of the outer coiled conductor positions over the swaging core and into the ring electrode. The outer coiled conductor is mechanically swaged between the ring electrode and the swaging core resulting in a mechanical and electrical joint. Insulation extends over the outer ends of the ring electrode and yields a bond to the ring electrode having substantially the same outer diameter as the ring electrode.

Abstract: Pacing lead including an elasticized snap-on sleeve integral with a fixation pad for covering and protecting a tip of an electrode, and which is designed for either ventricular or atrial pacing. The electrode includes a U-shaped mid-portion, and extends into and across a hole in the fixation pad. The bottom of the U-shaped portion is recessed slightly below the hole to a position slightly below the lower surface of the elasticized fixation pad. The pacing lead is intended for permanent epicardial pacing, includes a one piece design, provides for easy insertion, is acutely removable, is intended for long-term fixation and acute fixation, and has a low profile suitable for either ventricular or atrial pacing.

Abstract: Heart valve including an annular valve body having an inner wall defining a blood flow passage, a guide strut including an integral pivot surface extending radially inward of the valve body and a disc occluder having a central aperture engaged over the disc guide strut, a disc stop extending radially inward of the valve body opposite the guide strut, and pivot projections extending radially inward of the valve body and equally spaced from the guide strut whereby the disc pivots between occluding and non-occluding surfaces in response to downstream blood pressure gradients across the disc.

Abstract: Transvenous leads including an outer atrial and an inner ventricular spaced wound coils coaxial with respect to each other and including a closed fixation loop connected to the outer lead. The closed fixation loop extends outwardly at an angle with respect to the outer lead. An inner lead is slideably adjustable within the outer lead and supports a ventricular electrode. The outer lead supports an atrial electrode. A connector at the other end of the leads supports and secures a connector pin for the outer lead in one sleeve and provides for slideable adjustment of the inner lead which includes a proximal tip in the other sleeve. An O-ring engages in an O-ring groove in the other sleeve to provide a liquid seal between the atrial coil and the end of the ventricular coil. The proximal tip and connector pin connect to a pulse generator. The transvenous leads with the closed fixation loop are intended for pacing the ventricular and atrial chambers of a heart.

Abstract: Heart valve including a valve body having a non-circular exterior periphery and a blood flow passage orifice through the valve body having a periphery substantially geometrically similar to the exterior periphery. A rigid occluder having a periphery slightly smaller than the internal periphery of the blood flow passage, pivots within the confines of the blood flow passage. The valve body can assume an oval, egg, kidney, or the like geometrical shape and pivots on an axis parallel or removed from the major axis of the non-circular heart valve body. The occluder pivots about pivot closed pivots and pivot open pivots, guide struts, or a T-shaped pivot post between occluding and non-occluding positions. Stop surfaces all retain the occluder in the occluding position and non-occluding position in the heart valve orifice.

Abstract: A body implantable cardiac pacemaker having a Hall effect switch which may be activated by a magnetic field in order to alter one or more pacemaker characteristics. A circuit in the pacemaker produces a strobe signal which is used to turn on a current flow through the Hall effect element once each pacemaker pulse cycle for a period of 25.mu. sec. The Hall effect element is part of an integrated circuit and is oriented in a plane parallel to the broad plane of the pacemaker.

Abstract: A wrist watch size heart rate monitor coupled with a flexible metal expansion band detects a electrocardiac signal on one arm and applies that detected signal to electronic circuitry within the monitor. Means are also included for receiving a second electrocardiac signal from the other arm to obtain an electrocardiac lead I signal. The receiving means may be a contact member adapted to being placed in physical contact with a second flexible metal expansion band around the wrist of the other arm and having a like contact member associated therewith or the receiving means may be metal members adapted to having the thumb and a finger of the hand of the other arm squeezed thereagainst.

Abstract: A gamma ray scintillation camera generating (X,Y) spatial coordinate and Z energy signals relative to detected radiation events. The system provides for calibration of the camera Z signal response as a function of camera face location. In addition, the camera signals are converted to their digital equivalents subsequent to which the apparent coordinate locations of detected events as determined by the camera are corrected to their true spatial coordinates based upon correction information stored in the system.

Abstract: A programmable cardiac pacemaker pulse generator utilizing digital circuitry for controlling the provision of cardiac stimulating pulses. The pulse generator is capable of having the rate, the pulse width, the pulse amplitude, the refractory period, the sensitivity and the mode of operation programmed. In addition, the pulse generator can have the output inhibited and can respond to programming signals causing a threshold margin test to be performed, effects of closure of the reed switch overridden, a hysteresis function added and a high rate exceeding the normal upper rate limit programmed. Many of the programmable functions of the pulse generator can either be programmed on a permanent or a temporary basis. The pulse generator further includes means for signaling the acceptance of a programming signal, and means to reset the program acceptance circuit if extraneous signals are detected as programming signals.

Abstract: A programmable cardiac pacemaker pulse generator utilizing digital circuitry for controlling the provision of cardiac stimulating pulses. The pulse generator is capable of having the rate, the pulse width, the pulse amplitude, the refractory period, the sensitivity and the mode of operation programmed. In addition, the pulse generator can have the output inhibited and can respond to programming signals causing a threshold margin test to be performed, effects of closure of the reed switch overridden, a hysteresis function added and a high rate exceeding the normal upper rate limit programmed. Many of the programmable functions of the pulse generator can either be programmed on a permanent or a temporary basis. The pulse generator further includes means for signaling the acceptance of a programming signal, and means to reset the program acceptance circuit if extraneous signals are detected as programming signals.