For patients who received UFH or enoxaparin with fibrinolytic therapy, these agents may be continued uninterrupted through the PCI Transitioning from enoxaparin to either UFH or bivalirudin is possible, provided the last enoxaparin dose was >12 hours before PCI. Similarly, UFH may be transitioned to bivalirudin for PCI. Fondaparinux does not provide adequate anticoagulation for PCI, and additional intravenous boluses of UFH (or bivalirudin) should be administered.304 7. Coronary Artery Bypass Graft Surgery 7.1. CABG in Patients With STEMI: Recommendations Class I 1. Urgent CABG is indicated in patients with STEMI and coronary anatomy not amenable to PCI who have ongoing or recurrent ischemia, cardiogenic shock, severe HF, or other high-risk features.391 393 (Level of Evidence: B) 2. CABG is recommended in patients with STEMI at time of operative repair of mechanical defects.394 398 (Level of Evidence: B) Class IIa 1. The use of mechanical circulatory support is reason- able in patients with STEMI who are hemodynami- cally unstable and require urgent CABG. (Level of Evidence: C) Class IIb 1. Emergency CABG within 6 hours of symptom onset may be considered in patients with STEMI who do not have cardiogenic shock and are not candidates for PCI or fibrinolytic therapy. (Level of Evidence: C) CABG has a limited role in the acute phase of STEMI other than for cardiogenic shock, but it may be indicated for failed PCI, for coronary anatomy not amenable to PCI, and at the time of surgical repair of a mechanical defect, such as ventricular septal, papillary muscle, or free-wall rupture. Older case series highlighted a potential excess mortality risk for CABG when performed early after STEMI, which was related to worsen- ing myocardial injury from cardiopulmonary bypass, aortic cross-clamping, and cardioplegic arrest, with hemorrhagic transformation and infarct expansion. 