Abstract: A balloon catheter comprises a tip having a tapered distal end, a central lumen, and a balloon membrane coaxial with and surrounding the central lumen and connected to the tip. A sheath is slidable over the balloon to form an assembly, and a guide wire is slidable through the central lumen and insertable into a blood vessel for guiding the tip, membrane and sheath to a location within the blood vessel selected for therapy. The sheath fits loosely over the balloon, whereby the sheath can be withdrawn to expose the balloon at the selected location and the balloon can then be inflated to provide therapy.

Abstract: Disclosed herein is a pacer signal reject circuit wherein an entire ECG waveform signal is applied to one input of an operational amplifier, while only the initial portion of the pacer signal including the main pulse and a portion of the tail, is applied to the second input of such operational amplifier, to cause cancellation of that initial portion from the ECG signal. Also, a synthesized version of the remainder of such pacer tail is generated and applied to the second input. Thus, by isolating the ECG signal from the second input except for a timed period of the pacer signal, and by applying the synthesized tail signal to such second input, the entire pacer signal may be cancelled.

Abstract: An intra-aortic balloon adapted to be percutaneously inserted into a blood vessel in which the balloon and its support member are twisted as the balloon envelope is wrapped around its support member before insertion into the vessel to reduce the diameter of the balloon envelope. The support member is twisted as the balloon is wrapped, thereby storing energy which, urges the unwrapping of the balloon in the vessel. In one embodiment, the support member is hollow to permit a guide wire to pass there-through so that placement of the balloon within the human body may be done with greater precision and the hollow support member permits the injection of a radiopaque fluid so that the balloon can be viewed within the vessel, thereby assisting in the placement of the balloon. In another embodiment, a solid energy storage support member with a highly flexible distal portion provides an intra-aortic balloon of enhanced pliability.

Abstract: An inflatable and deflatable balloon catheter is disclosed. The inflatable chamber of the catheter is supported about an elongated support member of small diameter. One or both ends of the support member are rotatably disposed relative to the chamber wherein the chamber is adapted to being compactly twisted about the support member upon twisting, rolling or wrapping the chamber. The compactly twisted chamber has a small diameter whereby insertion of the catheter through a small incision and guiding thereof in a small body canal or passage is facilitated. A smooth-walled sheath of low friction material is disclosed for enclosing the twisted chamber to facilitate atraumatic entry of the catheter into the incision or body opening and for facilitating insertion and movement of the catheter. Balloon catheters according the present invention are advantageously used for intra-aortic balloon pumping.

Abstract: Apparatus and method for the percutaneous insertion of intra-aortic balloons into the human body wherein a sheath is provided which can be inserted into an artery through a puncture, and an intra-aortic balloon of a size sufficiently small and having sufficient flexibility is used which can be moved through the sheath into the artery. The apparatus and method includes, puncturing the skin into the artery until a needle means having a bore, introducing a guide wire into the artery through the needle means, advancing a dilator-sheath set over the wire to enlarge the puncture and to place an end of the sheath within the artery, withdrawing the dilator and guide wire and then inserting the balloon through the sheath.

Abstract: Inflatable and deflatable balloon catheters are disclosed. Catheters according to the invention have an expansion chamber that may be elongated to reduce its radial dimension without producing oblique or transverse folds or wrinkles. The inflatable chamber of the catheter is supported by an elongated support member of small diameter which has a continuously extending opening therein through which fluid is admitted to and withdrawn from the chanber. An axially movable elongating member is disposed within the expansion chamber for elongating the chamber. Axial movement of the elongating member elongates the chamber to decrease its radial dimension whereby feeding and guiding of the catheter is facilitated. In one embodiment, the support member is the gas supply tube extending into the chamber and the continuously extending opening is a helical slit running along at least part of the tube enclosed by the chamber.

Abstract: An inflatable and deflatable balloon catheter is disclosed. The inflatable chamber of the catheter is supported about an elongated support member of small diameter. One end of the support member is rotatable relative to the chamber wherein the chamber is adapted to being compactly twisted about the support member upon swiveling or rotation of the support member. The compactly twisted chamber has a small diameter whereby insertion of the catheter through a small incision and guiding thereof in a small body canal or passage is facilitated. A smooth-walled sheath of low friction material is disclosed for enclosing the twisted chamber to facilitate atraumatic entry of the catheter into the incision or body opening and for facilitating insertion and movement of the catheter. The support member is preferably made of a material which may be formed during use into a desired axial configuration by bending. Balloon catheters according to the present invention are advantageously used for intra-aortic balloon pumping.