Relation Between End-Procedural Activated Clotting Time Values and Radial Artery Occlusion Rate With Standard Fixed-Dose Heparin After Transradial Cardiac Catheterization

Although heparin administration has reduced the incidence of radial artery occlusion (RAO) during the transradial coronary angiography (TRCA), the effective activated clotting time (ACT) value for guiding unfractionated heparin dosing in patients undergoing TRCA is unknown. Four hundred thirty-two patients who were scheduled for elective TRCA were enrolled in our prospective study. All the patients received a standard dose of 5,000 IU unfractionated heparin. Anticoagulation level was assessed by ACT measurements that were taken at the end of the procedure just before the sheath removal. The day after TRCA, all patients were evaluated by color Doppler ultrasound to detect RAO. RAO was found in 29 patients (6.7%). A median ACT of 205 seconds in the RAO group and 265 seconds in the radial artery patent group were detected (p <0.001). Mean procedure duration was significantly longer in the RAO group than in the radial artery patent group (18.55 ± 9.80 vs 11.24 ± 7.07 minutes, p <0.001). There was a negative correlation between end-procedural ACT and procedure duration (r = −0.117, p = 0.015). In multivariate analysis, end-procedural ACT (odds ratio 0.981, 95% confidence interval [CI] 0.972 to 0.989, p <0.001), procedure duration (odds ratio 1.076, 95% CI, 1.037 to 1.116, p <0.001), and radial artery diameter (odds ratio 0.240, 95% CI 0.063 to 0.907, p = 0.035) were found as independent predictors of RAO. In conclusion, shorter end-procedural ACT levels, longer procedural duration, and smaller radial arterial diameter were independently associated with RAOs after TRCA with standard-dose heparin. In prolonged procedures, ACT-based heparin dosing may be useful to overcome RAO.