Abstract: An implantable medical electrical lead having a lead body including a stranded or cabled conductor extending therein and an electrical connector mounted to a proximal end of the lead body and coupled to the stranded or cabled conductor and having a fabric tube molded into a proximal portion of the lead body adjacent the electrical connector. The fabric may be a polyester mesh formed or rolled into a tube and is preferably molded into the proximal portion of said lead body adjacent its exterior surface. The proximal portion of the lead body may be fabricated of silicone rubber or polyurethane.

Abstract: A cam controlled pulsatile flow pump for neonatal and biventricular cardiac support systems wherein cylindrical cams having various profiles designed for a particular patient are selectively mounted on the output shaft of a motor. A roller follower engages the cam and is operatively connected to a compression plate under which at least one compressible conduit containing the patient's blood extends. The stroke volume of blood contained in the conduit can also be controlled.

Abstract: Micromachined thin film cantilever actuators having means for individually controlling the deflection of the cantilevers, valve members, and rudders for steering same through blood vessels, or positioning same within a blood vessel, for example. Such cantilever actuators include tactile sensor arrays mounted on a catheter or guide wire tip for navigation and tissues identification, shape-memory alloy film based catheter/guide wire steering mechanisms, and rudder-based steering devices that allow the selective actuation of rudders that use the flowing blood itself to help direct the catheter direction through the blood vessel. While particularly adapted for medical applications, these cantilever actuators can be used for steering through piping and tubing systems.

Abstract: A method and apparatus for measuring impedance of heart tissue or the leads associated with a cardiac stimulation apparatus involves charging a capacitor, storing the value of the voltage across the capacitor when charged, discharging the capacitor into said lead/heart system and storing the voltage on said capacitor when discharged. The two voltages may then be used to determine the combined impedance of the lead and the heart tissue. This may be advantageously accomplished by using separate circuits to measure each of the voltages of the capacitor and storing those voltages. These voltages then may be applied to an analog-to-digital converter which converts the ratio of said voltages to digital form. This value can then be used to calculate the combined impedance of the heart tissue or the lead. If one of the two impedances is known the other can then be easily determined.

Abstract: A system (10) is disclosed for facilitating the healing of traumatized tissue and broken or fractured bone. The system (10) establishes an electric field between a pair of electrodes (14) positioned on opposite sides of the patient site (12), resulting in the production of an alternating current having the desired frequency and amplitude characteristics in the tissue or bone. Specifically, the system (10) includes a resonator (32) formed by an inductor (36) coupled in series with the resistor (R1) and capacitor (C1) of an equivalent circuit (34) representing the patient site (12), the electrodes (14), and any gaps (30) therebetween. This resonator (32) also includes a capacitor (C2) designed to prevent spurious, high-frequency oscillations. The resonator (32) is operated by a free-running oscillator (16), which maintains the operation of the resonator (32) at its resonant frequency.

Abstract: Improved electrical leads provided by the surface treatment of silicone rubber tubing covering on implantable pulse generator, or IPG leads and the like by exposure of the silicone rubber to radio frequency glow discharge in a polymer forming or non-polymer forming gas at reduced pressure whereby improved slip properties are provided and binding between two or more of the leads in contact with each other is minimized.

Abstract: A low-power consumption implantable pacer includes a system for detecting evoked cardiac contractions in which pacing pulses are initially applied to a patient's heart in pairs such that at most only one pulse of a pair can induce capture. The lead recovery waveforms produced in response to each of the pulses of a pair are detected and compared. By selectively varying the pulse energy level, the patient's capture threshold is determined. Pulse energy is then increased such that the first pulse of each pair induces capture and the lead recovery waveform resulting from the second, non-capturing pulse is stored. To conserve battery current, single pacing pulses are then supplied to the heart, and the lead recovery waveforms developed by the single pulses are compared against the stored waveform to yield a reference difference signal which verifies capture.

Abstract: A portable, interactive medical electronic device exemplified by a defibrillator. The device obtains information about a patient's condition, such as ECG and transthoracic impedance data, directly from the patient, and information pertinent to the treatment of the patient indirectly through an operator of the device, and produces a medically appropriate action such as a defibrillation shock in response. Indirect information is obtained through information processing means that includes means for prompting the operator of the device and means for receiving the operator's responses thereto. Prompts may include both questions and instructions, and in one embodiment the information processing means obtains the assent of the operator before causing the defibrillation shock. Indirect information may include information as to whether the patient is conscious, and as to whether or not cardiopulmonary resuscitation has been performed.