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The utility of extension catheters in transradial percutaneous coronary intervention.

OBJECTIVES
To evaluate the use of extension catheters in transradial intervention of complex coronary lesions.


BACKGROUND
Complex percutaneous coronary intervention (PCI) via transradial approach remains a challenge for many interventionalists, primarily due to the difficulty in obtaining adequate guide catheter support.


METHODS
A retrospective case series identified 54 patients who presented for PCI of complex coronary lesions. A lesion was defined as complex if it contained severe calcification, proximal tortuosity, chronic total occlusion, or was located distal to a previously implanted stent. After identifying the complex lesions, a conversion to femoral approach was considered, but an attempt via the transradial approach with the use of an extension catheter was chosen as the initial strategy. Specific cases highlighting this approach are illustrated in detail.


RESULTS
The average age of the patients was 72 years old, with male predominance (55%). The success rate of completing the transradial intervention with the help of an extension catheter was 96%. Stent delivery failed due to severe tortuosity and calcification in only 2 cases. The coronary artery involved was either the left anterior descending (n = 25), the left circumflex (n = 10), the right coronary artery (n = 14), or a saphenous vein graft (n = 5). There were no coronary dissections evident from use of the extension catheter.


CONCLUSION
In the treatment of complex coronary lesions via the transradial approach, the use of an extension catheter may assist in improving successful intervention and decrease the frequency of crossover to a femoral approach.