Abstract: A cardiac assist device and method of use for assisting the function of a heart. The assist device includes a compressor positioned against the epicardial wall of the heart and a field generator for driving a fluid coupled to the compressor to exert pressure on the heart. The field generator may be a magnetic field generator and the fluid coupled to the compressor may be a ferrofluid. The compressor may include two containment regions containing ferrofluid on opposite sides of the heart, and a pair of compression portions coupled to the containment regions. The filled generator may be electromagnetic which includes two electromagnets having corresponding core portions and corresponding coils. The electromagnets may be disposed with their north and south poles in alignment and separated by a gap to allow relative movement. The electromagnets may be external or internal to the body.

Abstract: A percutaneous system for bypassing a restriction in a native vessel of a mammal having an aorta includes providing a graft having a body portion with a first end, a second end and a lumen therebetween. An aperture is formed in the aorta. The graft is inserted into the aorta and the first end of the graft is connected to the aorta about the aperture in the aorta. An aperture is then formed in the native vessel distal of the restriction. The second end of the graft is connected to the native vessel about the aperture therein such that the lumen in the graft communicates with the aorta and the native vessel.

Abstract: A restriction in a restricted vessel lying closely proximate the heart is bypassed. An aperture is formed in a supply vessel suitable for providing a blood supply. An aperture is formed in the restricted vessel distal of the restriction. Heart tissue is removed from the surface of the heart to form a channel in the heart tissue between the aperture in the supply vessel and the aperture in the restricted vessel distal of the restriction. The channel is covered to form a conduit to conduct blood from the supply vessel to the restricted vessel distal of the restriction.

Abstract: A balloon catheter which has an elongate shaft with an inflatable balloon connected to its distal end and a manifold connected to its proximal end. The manifold may be fixedly or removably attached to the shaft and includes a barrel with a plunger movably disposed inside it. The barrel has an internal volume of less than 5 cc and an internal diameter of less than 0.25 inches. A pressure transducer may be mounted to the manifold to permit measurement via a sensor tube. A pressure source for a balloon catheter including a barrel with a plunger inside it. The barrel is in fluid communication with the inflation lumen of the catheter and has an internal volume less than 5 cc and an internal diameter of less than 0.25 inches. A pressure sensor may be connected to the barrel with a sensor tube defining a fluid path from the interior of the barrel to the pressure sensor. A lock mechanism may be connected to the barrel to control longitudinal movement of the plunger.

Abstract: An electrophysiology energy treatment system for treating tissues within a patient's body with RF energy comprises an elongate catheter tube having a distal end, with a porous member thereon, insertable into the patient's body. An RF electrode is within the catheter tube adjacent the distal end and locatable within the patient's body, and an electrolyte fluid flows within the catheter tube for electrically connecting the electrode to the tissues to be treated within the patient's body.

Abstract: A vessel lies adjacent heart tissue, and a restriction in the vessel is bypassed. A chamber in the heart is accessed and a lumen is formed through the heart tissue which communicates with the vessel and a region distal to the restriction. Blood flows from the heart chamber into the vessel distal the restriction, thus bypassing the restriction.

Abstract: An in vivo source of mechanical energy is provided in close proximity to its load. In the disclosed embodiments, the mechanical energy source is a miniaturized motor ("micromotor") and the load is a miniaturized perfusion pump located at the distal end of a transluminal catheter. The motor is powerful enough to provide the electrical energy needed by the perfusion pump to fluid, and yet small enough to fit inside a body vessel. A position sensor may be provided for automatically controlling the motor's driving current so that it is corresponds to the applied load. An embodiment of the perfusion pump is also provided in which an external energy source is used. Another embodiment is provided wherein a balloon/pump/miniaturized-motor configuration is provided on a distal end of a catheter.

Abstract: An intravascular device and methods for forming multiple percutaneous myocardial revascularization (PMR) holes in a heart chamber wall simultaneously. One device includes a basket formed of flexible arms carrying cutting probes over their length. The basket arms are outwardly arcuately biased so as to assume an outwardly bowed, arcuate shape when unconstrained. The device includes an inner shaft distally secured to a proximal portion of the basket and slidably disposed within an outer shaft. The inner shaft and collapsed basket can be retracted within the outer shaft, delivered intravascularly to the left ventricle, and distally advanced, forcing the basket to assume the bowed shape. Radio frequency current supplied to the electrical cutting probes burn holes into the ventricle wall and myocardium. One embodiment has high pressure fluid jet cutting means. Another embodiment uses a basket as an anchor to position a steerable cutting probe.

Abstract: Devices and methods for creating a series of percutaneous myocardial revascularization (PMR) channels in the heart. One method includes forming a pattern of channels in the myocardium leading from healthy tissue to hibernating tissue. Suitable channel patterns include lines and arrays. One method includes anchoring a radiopaque marker to a position in the ventricle wall, then using fluoroscopy repeatedly to guide positioning of a cutting tip in the formation of multiple channels. Another method uses radiopaque material injected into each channel formed, as a marker. Yet another method utilizes an anchorable, rotatable cutting probe for channel formation about an anchor member, where the cutting probe can vary in radial distance from the anchor. Still another method utilizes a multiple wire radio frequency burning probe, for formation of multiple channels simultaneously. Still another method utilizes liquid nitrogen to cause localized tissue death.

Abstract: In order to bypass a restriction in a parent vessel, a first site in a branch vessel branching from the aorta is accessed intraluminally. An occlusion is formed at the first site, and the aperture is formed in the branching vessel, intraluminally, proximal of the first site. An aperture is formed in the parent vessel distal of the restriction, and a lumen is formed which communicates between the branching vessel proximal of the occlusion, and the parent vessel distal of the restriction.

Abstract: A percutaneous system for bypassing a restriction in a native vessel of a mammal having an aorta includes providing a graft having a body portion with a first end, a second end and a lumen therebetween. An aperture is formed in the aorta. The graft is inserted into the aorta and the first end of the graft is connected to the aorta about the aperture in the aorta. An aperture is then formed in the native vessel distal of the restriction. The second end of the graft is connected to the native vessel about the aperture therein such that the lumen in the graft communicates with the aorta and the native vessel.

Abstract: A guide wire that is capable of sensing pressure at its distal. The guide wire contains a non-compliant path from its distal end to a pressure transducer, at its proximal end, that has a maximum signal rating of 10-1,000 times the nominal signal.

Abstract: An apparatus is provided for closing a perforation in a wall of a patient's blood vessel or other organs, and a method of introducing the apparatus and causing the closure are described. The apparatus includes an elongated support member having a distal end supporting one or more tissue engaging hooks configured to engage fibrous vessel tissue when moved in a first direction and to disengage the tissue when moved in a second direction, and a proximal end for applying rotational torque to the support member to cause the hooks to engage collagen fibrous tissue in the adventitia of the blood vessel or fibrous tissue in other body organs. The hooks engaging the collagen fiber causes the blood vessel tissue surrounding the perforation to be drawn into close proximity such that the perforation can be closed. The apparatus can be removed by applying reverse rotation of the support member, whereby the hooks are disengaged.

Abstract: An electrophysiology energy treatment device for treating tissues within a patient's body with electrical energy comprises an elongate catheter tube having a distal end insertable into the patient's body. An electrode is within the catheter tube adjacent the distal end and locatable within the patient's body, and an electrolyte fluid flows within the catheter tube for electrically connecting the electrode to the tissues to be treated within the patient's body. A method of treating tissues within a patient's body with electrical energy is also provided.

Abstract: An intravascular device for measuring blood pressure and flow is disclosed, which includes an elongate shaft having a pressure transducer and a flow transducer connected to its distal end. The pressure transducer may be a ferrofluid-type pressure transducer and the flow transducer may be an anemometer-type flow transducer. Measurement circuitry is also disclosed which provides a means for simultaneous measurement of both blood pressure and blood flow parameters. A sensor shield may be employed to isolate radial blood flow which is indicative of turbulent blood flow. An alternative blood flow measurement device is also disclosed which utilizes a thin metal film anemometer to measure flow in a vascular lumen.

Abstract: A cryoplasty catheter and method for preventing or slowing reclosure of a lesion following angioplasty. The cryoplasty catheter includes a shaft having proximal and distal ends and a dilatation balloon disposed at the distal end. An intake lumen and exhaust lumen are defined by the shaft to deliver coolant to the balloon and to exhaust or drain coolant from the balloon. The method in accordance with the present invention includes cooling a lesion to aid in remodeling the lesion through dilatation and/or freezing a portion of the lesion adjacent the dilatation balloon to kill cells within the lesion to prevent or retard restenosis.

Abstract: A guide wire that is capable of sensing the phasic pressure at the distal end of the guide wire. The guide wire has a central lumen which provides a non-compliant fluid path from the distal end of the guide wire to a pressure transducer at the proximal end of the guide wire.

Abstract: An in vivo source of mechanical energy is provided in close proximity to its load. In the disclosed embodiments, the mechanical energy source is a miniaturized motor ("micromotor") and the load is a miniaturized perfusion pump located at the distal end of a transluminal catheter. The motor is powerful enough to provide the electrical energy needed by the perfusion pump to fluid, and yet small enough to fit inside a body vessel. A position sensor may be provided for automatically controlling the motor's driving current so that it is corresponds to the applied load. An embodiment of the perfusion pump is also provided in which an external energy source is used. Another embodiment is provided wherein a balloon/pump/miniaturized-motor configuration is provided on a distal end of a catheter.

Abstract: A balloon catheter is disclosed which includes a contrast displacement rod at least partially and slidably disposed in an elongate tubular member with a balloon connected to the distal end of the tubular member. The rod may include a stop mechanism to inhibit removal of the rod from the tubular member. A seal connected to the proximal end of the tubular member creates a liquid tight seal between the inside of the tubular member and the displacement rod. Accordingly, longitudinal actuation of the displacement rod causes the balloon to expand and/or contract. The balloon catheter may be a fixed wire, an over-the-wire or a single-operator exchange type balloon catheter. In addition, a pressure gauge may be connected to the proximal end of the tubular member. A one-way valve is also disclosed which allows the balloon catheter to be prepped via the guide wire lumen.

Abstract: A balloon catheter having a long shaft with an inflatable balloon connected to its distal end with a pressure source connected to the shaft at an invivo point which operates to inflate and deflate the balloon. The balloon catheter may be a fixed-wire type, an over-the-wire type, or an single-operator-exchange type catheter. The pressure source may include a piston and a chamber with an actuation member attached to the piston. The actuation member may be a solid rod or a hollow robe. In the case where the actuation member is a hollow tube, the tube may be used to introduce inflation fluid into the pressure source and the inflation lumen. A receptacle such as a reel or tubular hoop may be used to contain the actuation member when pulled proximally. A pressure sensor/gauge and a balloon sizing scale may be incorporated into the catheter assembly to assist the treating physician in monitoring the procedure.