The auxiliary instruments (Figure 1):

1) An 80-cm 18-gauge metal tube (Figure 1, B)
       The tube is inserted to lock with the inner lumen tube, thereby stiffening the catheter tip. The catheter tip is slenderized further by pushing the metal hub of the inner tube to a locked position (Figure 4, A). In this way, the balloon segment is stretched and made slender (diameter of 4.5 mm and length of 60 mm).

2) A 70-cm 14F polyethylene dilator (Figure 1, C)
       The dilator has a tapering tip. It is used to dilate the opening of the femoral vein and the atrial septum.

3) A 80-cm 0.038-inch high-torque J-tipped spring wire stylet (Figure 1, D)
       The stylet has a preformed J-shaped tip with a waist length of about 4.5 cm. It is inserted into the balloon catheter after the balloon segment is placed in the left atrium to provide an excellent steerability to the catheter. Axial movement of the catheter is made by 1:1 torque control of the stylet. When the stylet is withdrawn from the catheter, the catheter tip advances forward, and vice versa.

4) A 180-cm 0.025-inch stainless steel guide wire with coiled floppy tip (Figure 1, E)
       The guide wire is inserted through the transseptal catheter to the left atrium to guide the balloon catheter to the left atrium.

5) A 30-cc plastic syringe and a connecting tube (Figure 1, F)
       The extent of balloon inflation is controlled by adjusting the volume of diluted contrast material in the syringe, which is injected manually into the catheter through a two-way stopcock (see Figure 3, B in the Balloon Catheter section).

6) A ruler (Figure 1, G)
       The ruler is used to measure the diameter of inflated balloons in pretestings before insertion of the catheter into the patient.

Figure 1
Inoue Balloon Catheter and Auxiliary Instruments