Radial approach for percutaneous coronary interventions on chronic total occlusions: technical issues and data review

To overview the scientific data and the technical details regarding percutaneous coronary interventions (PCI) on chronic total occlusions (CTO) by radial approach.

Trans-femoral approach is commonly regarded as the standard for PCI on CTO.

A systematic search in Medline and in the main international websites was realized. Key data were extracted and analyzed using standard meta-analytic techniques. Bench test assessment of compatibility between different combinations of interventional devices (required for CTO recanalization techniques) and the following guiding catheters was performed: 5 Fr, Sheathless 6.5 Fr, 6 Fr, Sheathless 7.5 Fr and 8 Fr.

No prospective randomized study was found, whereas 13 observational studies on 3,501 CTOs treated by radial approach were identified. Overall, the crossover to femoral access rate ranged between 0 and 5.8%. Access site complications were noted in <1% of cases and in-hospital major adverse events were reported in 0-3.8% of patients. PCI success was significantly influenced by the learning curve: In the five studies comparing the success rates between a first and a later period of practice, a significant improvement was observed (OR, 95% CI: 0.30, 0.39-0.51; P < 0.001). The technical details relevant to approach a CTO by transradial access are discussed, and the original results of bench tests provide details regarding the compatibility of various CTO recanalization techniques with specific guiding catheter sizes.

The transradial access represents a promising alternative to trans-femoral access to treat patients undergoing CTO PCI in high-volume transradial centres. The presented data may be useful to plan transradial PCI attempts on CTO lesions.