Native coronary and bypass graft cannulation through transradial approach: Technical considerations

OBJECTIVES: The aim of this review is to discuss different methods using the transradial approach (TRA) of accessing the native coronary arteries and bypass grafts to optimize the quality of angiographic results and support for interventional procedures. BACKGROUND: Successful coronary cannulation provides the basis for optimal angiography and interventional success. There is limited literature describing successful transradial techniques of coronary and bypass graft cannulation. In this review, a variety of different challenges and their solutions are provided. METHODS: Successful TRA methods for routine cannulation and modified methods for challenging cannulation of both native coronaries and bypass grafts are described based on the experience of several high-volume radial operators. RESULTS: Differences in catheter/vascular lumen interactions endow different operating characteristics to catheters depending on whether the femoral or either radial approach is used. Understanding these differences contributes to success in TRA. In addition, techniques for cannulation of anomalous coronary origin, use of special catheter curves, small and large lumen guide catheters, sheathless guide catheters, universal catheters, and a special technique to cannulate the internal mammary artery from the contralateral radial artery are reviewed, with supporting figures. CONCLUSIONS: Despite lower bleeding and vascular complication rates as compared with transfemoral approach (TFA), the adoption of TRA has been relatively slow, particularly with cases of complex anatomy such as bypass graft cannulation. Anatomical challenges at various levels of the catheter course play an important role in TRA coronary and bypass graft cannulation failure. A logical approach and understanding of these challenges can augment procedural success and enhance quality.