Lumen-Following Safety J-Guide for Catheterization of Tortuous Vessels

Atherosclerotic tortuosity and intimal reconfiguration add to the difficulty and risk of arterial catheterization regardless of how it is performed. The use of small J -shaped catheters as temporary, path-finding substitutes for conventional guides has earned wide acceptance (1). Although effective in principle, this technic requires procedural catheter changes which are time-consuming, inconvenient, and sometimes sanguinary. J-Guide A conventional movable core guide spring is heated and preshaped into a J configuration 6 mm across. This guide is then used in place of a J -catheter. A similar simultaneous development has been reported by others (3). In use, the J-guide is subjected to relatively hazardous stresses produced by repeated manipulation and sharp angulation of an already weakened heat-deformed tip. The chance of breakage is increased: indeed, such a tip was lost in a patient with severe arteriosclerotic peripheral vascular disease. Safety J-Guide2 After development of the safety guide (2), the J-guide was modified to include the same protective feature. An internal safety wire small in diameter is soldered within the tip of the guide; it then extends to the proximal end of the guide where it is again soldered (Fig. 1). This small but strong wire insures against loss of a broken guide tip and prevents uncoiling of the spring loops under stress. Technic After the percutaneous femoral arterial puncture, a standard guide is threaded through the needle and an attempt made to traverse the iliac lumen into the aorta. If resistance to passage is encountered, the guide is removed (Fig. 2, A, B). A Safety J-Guide is straightened by advancing the mandril into the preformed curved tip (Fig. 1). It is then inserted into the needle, and the mandril is withdrawn 3 to 4 cm to permit the J-tip to reform as the guide enters the iliac artery. Under fluoroscopic control, the reformed J is gent ly advanced, usually without difficulty, within the tortuous vessels (Fig. 2, C, D). In some cases the curved j-tip may not negotiate multiple sharp bends or unusually heavy atheromatous build-ups. Should this occur, the mandril is withdrawn enough to allow a long segment of the guide to become flexible. With gentle pressure against the rounded guide tip, the flexible segment is formed into an intravascular loop (Fig. 2, E, F, G). Further pressure then elongates the loop, causing it to advance within the vessel, leaving the J-tip behind. The action is much like that of the tread of a Caterpillar tractor, and the guide loop thus formed will follow the lumen of almost any unobstructed vessel. Once the aorta is reached, both limbs of the loop can be advanced to allow the guide to be straightened. If the guide spring will not advance after a brief period of gentl e manipulation with varying amounts of stiffening, the procedure should be discontinued and another vessel chosen for entry.