Abstract: An apparatus and a method for fixing a heart valve is disclosed that produces a differential pressure across the outflow section of the heart valve to the exterior of the valve that may be made relatively large while the differential pressure across the valve leaflets is small or zero. The invention comprises attaching the outflow section of a heart valve to a source of pressurized fluid; placing a small tube through the leaflets and plugging the inflow section. The tube is preferably attached to a cannula plug that plugs the inflow section of the valve. The tube has a fluid inlet near the connection point of the tube to the cannula plug to allow fluid around the connection point to enter the tube. The tube opens at its opposite end to form a fluid channel from a point near the connection of the cannula plug to the tube through the opposite end of the tube. The tube allows fluid in the outflow section to move across the leaflets to the inflow section.

Abstract: A natural tissue heart valve includes a tubular wall having an outflow section and valve leaflets which allow flow into the outflow section. A heart valve of this type is subjected to a fixative fluid to provide a first differential fluid pressure across the tubular wall of the outflow section and a second differential fluid pressure across the valve leaflets. The first differential fluid pressure acts outwardly on the tubular wall, and the differential pressures are unequal.

Abstract: A mitral valve is removed from a pig heart with the annulus, leaflets, cordae tendineae and papillary heads intact. The porcine mitral valve is fixed. A covering material is attached to the papillary heads around the cordae tendineae. A sewing tube of a flexible material is attached to each of the papillary heads by sutures that extend through the covering material. The sewing tube extends away from the porcine mitral valve's papillary head remnants. A covering material is attached to the annulus. A human heart with a diseased or damaged human mitral valve is imaged in vivo to size the length between the mitral valve annulus and the papillary heads. The porcine mitral valve annulus to sewing tube length is adjusted to match the like dimension in the human heart by trimming the sewing tube. The human heart is opened and the mitral valve excised. The human heart's cordae tendineae are removed leaving the papillary heads intact.

Abstract: A perfusion system incorporating a sealed reservoir in communication with a pump which allows any negative pressure at the suction inlet of the pump to be communicated into the reservoir and thereby communicated to any lines connected to the sealed reservoir. The sealed reservoir provides filtration and defoaming elements. An oxygenator and a heat exchanger may be connected to the outlet of the pump to prepare the blood for return to the patient. A control system which operates clamps and displays pressure, temperature, fluid level, and other information measured at various points in the perfusion system, is utilized with a perfusion system. In another embodiment, a hard-shell reservoir utilizing an outlet located at the bottom of the reservoir, said outlet having integral to that outlet a floating ball valve, to where the valve will be opened if there is fluid in the reservoir and closed if no fluid exists in the reservoir.

Abstract: A mitral valve is removed from a pig heart with the annulus, leaflets, cordae tendineae and papillary heads intact. The porcine mitral valve is fixed. A covering material is attached to the papillary heads around the cordae tendineae. A sewing tube of a flexible material is attached to each of the papillary heads by sutures that extend through the covering material. The sewing tube extends away from the porcine mitral valve's papillary head remnants. A covering material is attached to the annulus. A human heart with a diseased or damaged human mitral valve is imaged in vivo to size the length between the mitral valve annulus and the papillary heads. The porcine mitral valve annulus to sewing tube length is adjusted to match the like dimension in the human heart by trimming the sewing tube. The human heart is opened and the mitral valve excised. The human heart's cordae tendineae are removed leaving the papillary heads intact.

Abstract: An annuloplasty ring having an adjustable configuration. The ring takes the form of a tubular sleeve surrounding frame members which be deflected by means of drawstrings.

Abstract: A methods and apparatuses for ablation or hyperthermic treatment of body tissue are disclosed, wherein the application of radio-frequency ablative or hyperthermic energy is accompanied by the infusion of a conductive solution into the tissue, such that a virtual electrode is created. The virtual electrode results from the increased conductivity of the tissue in the area being treated due to the presence of conductive solution, such that the area of tissue being treated is enlarged as compared with non-fluid-assisted application of energy. In one embodiment, a catheter having a hollow helical electrode/needle on the distal end thereof is provided, such that the electrode/needle can be screwed into the tissue to be treated. A conductive fluid, such as saline, saturated saline, or Ringer's solution, is infused into the tissue to be treated via the hollow electrode and a lumen extending along the length of the catheter.

Abstract: The present invention is an outlet connector configuration for an oxygenator that prevents excessively high positive or negative pressure from forming in the oxygenator and helps to minimize the possibility of misidentifying the outlet connector. The outlet connector is hollow and substantially cylindrically tubular in shape so that a hollow inner conduit is formed. The outlet connector is in fluid communication with the outlet manifold of an oxygenator through the inner conduit. In one embodiment, the outlet connector has an elongated hole extending through the tubular material of the outlet connector into the hollow inner conduit formed therein. The elongated hole is preferable large enough to be felt by the fingers of the person connecting tubing to the outlet connector. The elongated hole is preferably arrow shaped with the arrow pointing in the direction of fluid flow out of the outlet manifold.

Abstract: A two-staged venous cannula is disclosed. The cannula includes an expandable reinforcing member around the atrial basket that prevents the cannula from kinking or collapsing in the area where the reinforcing member is applied. The reinforcing member preferably consists of an even number of rigid discrete beams of the same length equally spaced about the circumference of a cylinder. In an alternate embodiment, the beams may be equally spaced on the surface of a cone. Alternate spaces between the beams are formed. The alternate spaces between the beams are equally spaced around the circumference of the cannula. The alternate spaces between the beams remain equally spaced around the circumference of the cannula as the reinforcing member is expanded over a larger diameter. This design for the reinforcing member provides space between the beams where holes of the preferred shape, size and orientation can be placed through the cannula without requiring cutting through the material of the reinforcing member.

Abstract: A holder for a prosthetic heart valve is disclosed. The holder, comprising a holder assembly disposed at the distal end of an elongate handle, includes a plurality of distally-projecting fingers adapted to engage the commissure posts of a stented prosthetic valve. The commissure-engaging fingers are movable in a radially-inward direction toward the longitudinal axis of the holder. A mechanism is provided for retaining the fingers in an inwardly-moved position. When the commissure posts of the valve are coupled to the fingers, inward movement of the fingers causes the commissure posts to be deflected inward with respect to the valve, improving the implanting surgeon's access to the valve's suture ring and surrounding tissue.

Abstract: An overpressure safety valve assembly for use during heart surgery is disclosed. The assembly comprises an elongated tubular body portion having an inlet end, and an outlet end and an unidirectional valve disposed therebetween. A relief valve portion is joined to and in flow communication with the tubular portion. The relief valve portion includes a first relief valve configured to open if the pressure within the overpressure safety valve diminishes below a predetermined level, and a second relief valve configured to open if the pressure adjacent the outlet end exceeds a predetermined level. The first and second relief valves are disposed in a side by side configuration in a common conduit.

Abstract: Pure unalloyed pyrocarbons having wear resistance suitable for use in pyrocarbon-coated heart valve components and having mechanical properties, such as flexural strength and toughness, superior to commercial silicon-alloyed pyrocarbons are deposited in fluidized bed coaters. Coating conditions are carefully controlled so as to maintain a precise bed size within a defined coating enclosure which will assure a substantially constant surface deposition temperature that in turn assures deposition of homogenous unalloyed pyrocarbons having these improved mechanical properties.

Abstract: Body-implantable leads with open, unbacked (uninsulated) electrode structures having electrical discharge surfaces formed by conductive elements, such as mesh and braid, and preferably coils. The electrode structures can be classified by pattern: (1) loops, (2) linear arrays and (3) radial arrays. The electrodes are located on or near the epicardial surface of the right and left heart.

Abstract: A method and apparatus for converting an arrhythmia of a heart using a biphasic truncated exponential waveform wherein the first phase is of shorter duration than the second phase.

Abstract: An implantable defibrillator/cardioverter which generates a biphasic defibrillation/cardioversion waveform including a pulse generator comprising two capacitors and a pair of switches for connecting the capacitors in parallel during a first phase and in series during a second phase. The first phase has a small "tilt" between the leading edge voltage and the trailing edge voltage. The second phase has a leading edge voltage which is approximately twice the trailing edge voltage of the first phase.

Abstract: An electromagnetic radiation susceptor material comprises at least one species of particle dispersed in a dielectric binder material. Any dispersed species of particle comprises a ferromagnetic amorphous alloy having the composition F.sub.100-y-x M.sub.y TM.sub.x, where M is one or more magnetic elements selected from the group consisting of Fe, Co, and Ni; M is one or more metalloids selected from the group consisting of B, C, Al, Si, P and Ge; TM is one or more transition metal selected from the group consisting of columns IIIB (including the rare earths) to VIIB of the periodic table, and especially Ti, V, Cr, Mn, Zr, Nb, and Ta; 0.ltoreq.x.ltoreq.20; and 10.ltoreq.y.ltoreq.30. The transition metal controls the Curie temperature of the alloy to provide temperature self-regulation. Many types dielectric binder are suitable. The susceptor material may be applied to substrate, such as an electrically conductive material.

Abstract: A layered microwave radiation absorber comprises an absorbing layer bound to one side of a conductive layer (such as a metallic plate or foil), and an adhesive layer bound on the other side of the conductive layer. The combination may be applied directly to the surface of any object, but especially to an existing conductive object coated with an nonconductive coating (such as paint) without removing the nonconductive coating from the surface. Several types of absorbing materials may be used, and other layers may be included. The absorber has superior resistance to delamination.

Abstract: An imaging system employs a photoconductive material capable of bearing a latent photostatic image, a plurality of elongated parallel stripes adjacent the photoconductive material, selective scanning of the stripes to produce charge carriers within the photoconductive material, and time-ordered detection of the current created by the charge carriers with the plurality of elongated parallel stripes. Appropriate addressing of the stripes as they are scanned produces a pixellated representation of the latent image. The system has improved output signal strength and higher resolution than known systems.

Abstract: A conductive coating on a thin glass strip senses the image signal on a selenium coated photoimaging plate as the plate is scanned with a laser beam. The glass strip is suspended over the surface of the plate with finger-like members. The finger-like members that support the strip are spring loaded downward toward the plate, but are suspended above the plate by a pressurized cushion of air. The strip bends to assume the surface profile of the plate, thus maintaining uniform spacing even though the plate may not be flat and may even have a varying profile along its length.

Abstract: A responder assembly for an article inventory control system employs a plurality of sensors for detection of sensitized markers attached to inventory items. By processing signals from each of the plurality of sensors, a detection pattern is provided to determine whether none, one, or more than one marker is present within a zone of sensitivity.