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Nonocclusive radial artery injury resulting from transradial coronary interventions: radial artery IVUS.

OBJECTIVE
The purpose of the present study was to evaluate nonocclusive radial artery injury resulting from transradial access.


BACKGROUND
The benefits of transradial access for coronary intervention have been well documented, but resulting intima-media hyperplasia could be a limitation.


METHODS
Thirty patients undergoing transradial coronary intervention (Group A: 15 de novo procedures, Group B: 15 previous transradial procedures) underwent radial artery intravascular ultrasound (IVUS) before catheter insertion. IVUS abnormalities were evaluated in the 100 mm segment proximal to the access site using automatic pullback in the serial mode. A study segment was then selected for continuous cross-sectional recording to evaluate the effects of a spasmolytic cocktail on radial artery IVUS dimensions which were measured at baseline and at one-minute intervals after administration of 0.8 mg sublingual nitroglycerin (NTG) and 3 mg intra-arterial verapamil (V). Differences in the two groups were evaluated.


RESULTS
Intimal hyperplasia and/or intima-media thickening was present in all patients in Group B. The baseline radial artery IVUS area was significantly smaller in Group B, despite the preponderance of males in this group (6.7 +/- 0.8 mm2 Group A versus 5.0 +/- 0.7 mm2 Group B; p < 0.01). Area increased significantly after NTG and V, but Group B area remained smaller than that of Group A.


CONCLUSION
In patients with previous transradial access, evidence of nonocclusive injury can be demonstrated in the segment corresponding to the sheath location. Intimal hyperplasia was present and IVUS dimensions were significantly smaller, but the vasodilatory response to spasmolytic drugs was maintained.