Abstract: An R-wave detection system includes an electrode for placement in close proximity to or in contact with a heart to sense electrical activity of the heart. A signal processor is in communication with the electrode, and is responsive to receipt of the analog signal from the electrode to condition the signal to account for noise and far-field effects. The system is operative to determine whether the conditioned signal exceeds a dynamic threshold value and, if so, the system generates a synchronization pulse to indicate the rising edge of an R-wave.

Abstract: A cardiac support system includes a ventricular assist device adapted to be extended over a portion of a patient's heart to assist the ventricles of the heart to properly contract. One or more stimulating electrodes are mounted on the ventricular assist device in selected locations such that when the ventricular assist device is extended over the heart, the stimulation electrodes are in close proximity to the surface of the heart. The system further includes one or more external pick-up electrodes that receive externally applied energy and conduct that energy to the one or more stimulating electrodes via conductive leads. The external pick-up electrodes may be mounted on the outer surface of the ventricular assist device, or can be located at some other location inside the patient's body. The externally-applied energy will typically be supplied by standard defibrillation paddles located outside of the patient's body.

Abstract: A cardiac assist system includes a sensor that is operative to sense the electrical activity of a patient's heart. The sensed electrical activity is processed to determine the onset of ventricular contraction. A compressive force from a ventricular assist device is applied to the ventricles during at least a portion of the heart's ventricular contraction. The cardiac assist system also includes an electrical stimulating system. Thus, in the event the heart begins to fibrillate, the electrical stimulating system is actuated to apply stimulating pulses to the heart.

Abstract: A ventricular cuff is designed to assist a heart to pump blood by applying uniform pressure to a majority portion of an exterior ventricular surface of the heart. A heart engaging structure is preferably provided for releasably engaging the heart to hold the heart in place relative to the cuff. The ventricular cuff includes an outer shell, an inflatable inner bladder and a fastener assembly. The heart engaging structure and ventricular cuff define an upwardly opening chamber sized for receiving a heart. The bladder has an opening for communication with a source of fluid under pressure so that the bladder is cyclically inflated and deflated at a predetermined rate to assist the ventricles of the heart to properly contract.

Abstract: A heart assist device intended for the long term support of certain late-stage cardiac failure states, particularly those known in the practice of cardiology to be called a dilated cardiomyopathy. A method is described wherein a "viscous cardioplasty jacket" is fashioned to provide a buttressing effect to the ventricular heart walls to thus render a more efficient cardiac contractile mechanism whereby the patient is afforded improved heart function to allow increased physical activities. Such a viscous compliant enclosure of the ventricular heart masses can be utilized concurrently with recognized drug therapy which is sometime lacking in beneficial effect for these patients and is far less traumatic than the currently practiced surgical cardiomyoplasty (CMP) procedure. Application of this device may be accomplished through a relatively non-invasive endoscopic procedure in a more refined methodology of anatomical implantation of the device.

Abstract: An apparatus and method for assisting a heart to pump blood includes a housing that defines an internal chamber for receiving a heart. The housing has a first opening to supply fluid to the internal chamber of the housing. Uniform pressure is applied to at least a majority portion of an exterior ventricular surface of a heart that is placed within the internal chamber so that the heart is substantially uniformly deformed to simulate a systolic phase.

Abstract: An inflation system for independently controlling the rise time and plateau level of a pressure profile applied to an inflatable chamber includes a pneumatic source disposed in fluid communication with a pressure path including a regulation device for establishing respective high and low pressure levels. A supply mechanism is disposed at the output of the pressure path and is operative to alternately expose the inflatable liner to the high and low pressure levels to define an independently controllable rise time.