Although measurements are useful to show that an anti-IIa anticoagulant has been given, the value of the activated clotting time in current practice has been questioned. Although studies in the balloon angioplasty era did demonstrate a relationship between activated clotting time levels and ischemic complications,653 655 more recent analyses from the coronary stent era have not found a clear relationship between activated clotting time and out- comes.349,656,657 There may, however, be a modest relation between bleeding and activated clotting time levels.349,657 In addition, not only are there differences between activated clotting time levels measured by Hemochron and HemoTec devices, but both devices have less than optimal precision.658 Thus, although traditional target activated clotting time levels are included in this document, the utility of measured acti- vated clotting time levels in current practice should be considered uncertain. Levine et al 2011 ACCF/AHA/SCAI PCI Guideline e607 Most cardiologists remove femoral sheaths when the acti- vated clotting time falls to 150 to 180 seconds or when the activated partial thromboplastin time falls to 50 seconds. Full-dose anticoagulation is no longer used after successful PCI procedures. Almost all large clinical trials have enrolled patients who underwent transfemoral PCI, but recent small studies assessing the transradial approach have used similar doses of UFH659 and similar activated clotting time target 5.7.4.3. Enoxaparin: Recommendations Class I 1. An additional dose of 0.3 mg/kg IV enoxaparin should be administered at the time of PCI to patients who have received fewer than 2 therapeutic subcu- taneous doses (eg, 1 mg/kg) or received the last subcutaneous enoxaparin dose 8 to 12 hours before PCI.649,661 664 (Level of Evidence: B) Class IIb 1. 