Abstract 4188: The Assessment of Acute Injuries and Chronic Intimal Thickening of the Radial Artery After Transradial Intervention by Optical Coherence Tomography
Backgrounds: The transradial coronary intervention (TRI) has emerged as a standard in many centers due to less bleeding complications and earlier patient ambulation. However, TRI induces a trauma to the radial artery (RA) that could possibly influence the patency if subsequently used as a bypass conduit. We sought to determine the nature and extent of acute and chronic effect of TRI on RA by optical coherence tomography (OCT).
Methods: We studied 44 RAs in 36 patients who underwent TRI with coronary OCT imaging. RAs were divided into first-TRI group (fTRI) and repeated-TRI group (rTRI). Immediately after the completion of TRI with 16cm 6F or 7F sheath, 0.5mg isosorbide dinitrate was administered and RA angiography was performed to identify the location of the sheath chip and RA ostium. OCT imaging wire was then inserted proximal to the RA ostium, and the sheath was removed 2cm distal to the puncture site. Automated pull-back imaging was repeatedly performed with upper-arm tourniquet and Ringer’s solution injection to examine from RA ostium to the sheath chip. Intimal tear and medial dissection were examined by two independent observers and disagreement was resolved by consensus reading. Intimal and medial area, intimal and medial thickness, and % narrowing were measured. Frequency of acute injuries was assessed with respect to the location (proximal(P): RA ostium - sheath chip, mid(M) and distal(DIS): divided by the center of the sheath located during TRI), and intimal thickening was evaluated at 3cm, 10cm, 17cm distal to the puncture site.
Results: Mean examination lenth was 16.2±1.3cm, and mean length from the sheath chip to RA ostium was 4.1±1.3cm. Intimal tear was frequently observed in DIS (p<0.05) than in P. Medial dissection tended to cluster in P and DIS. Intima/medial area (0.61±0.34 vs 0.38±0.14, p<0.05), max intimal/medial thickness (1.24±0.91 vs 0.74±0.44, p=0.06), and % narrowing (41.9±9.3% vs 33.9±9.9%, p<0.05) in DIS were all greater in rTRI compared with in fTRI, whereas no significant difference was detected in M and P between 2 groups.
Conclusion: Acute RA injury and chronic intimal thickening by TRI was clearly visualized by OCT. Interventionalists should be aware of this effect of TRI on RA, and effort should be made to reduce trauma when choosing TRI.