Abstract: An intravascular device for forming a channel within a patient's ventricular wall which engages the tissue of the ventricular wall to prevent undesirable movement of the channel forming device while forming the channel.

Abstract: The invention is directed to an introducer which is formed of a relatively rigid tubular member having an inner lumen and an elongated slot in the distal portion of the introducer. The introducer is particularly suitable for introducing an elongated channel forming device having radially extending arms for limiting the depth of penetration into a guiding or delivery catheter. By pulling the channel forming member into the inner lumen of the introducer, the radially extending arms are bent or folded forwardly into the inner lumen and they remain in this position until they extend out the distal end of the guiding or delivery catheter.

Abstract: An optical fiber device for forming channels within a wall of a patient's heart, and particularly the epicardium, which has an elongated optical fiber, a probe tip secured to the distal end of the optical fiber and an outer support tube secured to the proximal portion of the probe tip and a distal portion of the optical fiber proximal to the probe tip. In another embodiment the optical fiber device has an elongated optical fiber, a probe tip secured to the distal end of the optical fiber and a radiating step or projection on the exterior of the probe tip to act as a stopping surface to control the depth of penetration of the probe tip into tissue.

Abstract: A balloon dilatation catheter for the dilatation of a prostatic urethra having a reinforcing element extending through the elongated shaft of the catheter to prevent significant elongation or failure of the catheter and a traction member for assisting in the resistance to substantial tensile stresses. The balloon dilatation catheter also includes an expandable means between the balloon and catheter shaft to extend the length of the balloon when it is deflated. The extension of the deflated balloon prevents the balloon from bunching up and interfering with the withdrawal of the balloon through the working channel of the cystoscopic sheath upon the completion of the dilatation. The catheter has a marker for easy visualization so that the balloon can be positioned reliably and a tip construction so that the catheter can be advanced into the bladder safely.