Use of slender catheters for transradial angiography and interventions.

Currently the 0.014-inch guidewire is commonly used for coronary intervention and all devices are 0.014 inch-compatible. The size of common guiding catheters is 6-F or 7-F. However, PCI requires oral administration of antiplatelet agents, and punctured-site complications such as hemorrhage and hematoma occur more frequently with use of a 6-F or 7-F guiding catheter compared to a 5-F guiding catheter. Moreover, 6-F or larger guiding catheters may cause radial arterial occlusion, although the transradial approach causes less punctured-site complications compared to the transfemoral approach. Recently, 0.010-inch guidewires applicable for the Kissing Balloon Technique (KBT) using a 5-F guiding catheter and 0.010-inch guidewire-compatible balloons have been developed in Japan, and a 3-F angiography catheter has also been developed. We refer to these devices as the "Slender System", and we have used this system for active treatment of bifurcation lesions and chronic total occlusion (CTO). In this report, we describe angiography using a 3-F catheter, the KBT using a 5-F guiding catheter and 0.010-inch guidewires, and treatment of CTO using a 5-F catheter and 0.010-inch guidewires. For CTO treated using the Slender System at our facility, the transradial arterial approach was used in 96% of cases, treatment using the Slender System alone succeeded in 68%, and the overall success rate was 89%. Therefore, our results show that complex lesions may be treatable using the Slender System, and that not all complex lesions require a 6-F or larger guiding catheters, a femoral arterial approach, or bilateral guiding catheters.