Intima-media thickening of the radial artery after transradial intervention: An intravascular ultrasound study

Objectives We sought to assess the extent and nature of radial artery injury after transradial intervention (TRI) using intravascular ultrasound (IVUS). Background Although TRI has been developed to minimize bleeding and improve the quality of life, radial artery injury is a problem. Methods We studied 100 radial arteries in 100 consecutive patients who underwent coronary IVUS imaging. To assess the injury to the radial artery, we compared the radial artery findings between first-TRI patients (n = 48) and repeat-TRI patients (n = 52). Ten cross-sections at 5-mm intervals from the puncture site along a 50-mm distance were measured in each patient. Results In repeat-TRI patients, the lumen area (LA) and minimal lumen diameter (MLD) were smaller than those in first-TRI patients (p = 0.032 and P = 0.028, respectively), whereas the intima-media cross-sectional area (IMcsa) and intima-media thickness (IMT) were significantly greater than those in first-TRI patients (p < 0.01). In the proximal radial artery, there were no significant differences in the vessel area (VA), LA, IMcsa, or MLD between the two groups. In the distal radial artery, both LA and MLD were significantly smaller in repeat-TRI patients than in first-TRI patients (p < 0.01), whereas IMcsa and IMT were greater in repeat-TRI patients than in first-TRI patients (p < 0.01). However, VA did not differ between the two groups. Conclusions The lumen diameters were smaller in repeat-TRI patients than in first-TRI patients due to intima-media thickening, especially in the distal radial artery. Care should be taken when the radial artery is used as a conduit in coronary artery bypass graft surgery, particularly in patients who have undergone TRI.