When do you discontinue heparin (Heparin) drip in Non-ST-Elevation Myocardial Infarction (NSTEMI) management?

When to Discontinue Heparin Drip in NSTEMI Management

Heparin drip should be discontinued after PCI for uncomplicated cases, or continued for at least 48 hours or until discharge if medical management is selected for NSTEMI patients. 1

Discontinuation Timing Based on Management Strategy

After Percutaneous Coronary Intervention (PCI)

• Discontinue anticoagulant therapy (including heparin drip) after PCI for uncomplicated cases 1
• If bivalirudin was used during PCI, it can be discontinued immediately after the procedure in uncomplicated cases 1

For Medically Managed Patients (Conservative Strategy)

• Continue intravenous unfractionated heparin (UFH) for at least 48 hours or until discharge if medical therapy is selected 1
• For patients receiving enoxaparin, continue for the duration of hospitalization, up to 8 days 1
• For patients receiving fondaparinux, continue for the duration of hospitalization, up to 8 days 1
• For patients receiving bivalirudin, either discontinue or continue at a reduced dose of 0.25 mg/kg per hour for up to 72 hours at the physician's discretion 1

Special Considerations for CABG

If coronary artery bypass grafting (CABG) is selected as the management strategy:

• Continue UFH if the patient is already receiving it 1
• If the patient is on enoxaparin, discontinue 12-24 hours before CABG and transition to UFH per institutional practice 1
• If the patient is on fondaparinux, discontinue 24 hours before CABG and transition to UFH per institutional practice 1
• If the patient is on bivalirudin, discontinue 3 hours before CABG and transition to UFH per institutional practice 1

Monitoring Considerations

• For patients on UFH, monitor activated partial thromboplastin time (aPTT) to ensure therapeutic anticoagulation while the drip is running 2
• Be aware that direct oral anticoagulants (DOACs) can affect heparin anti-Xa assays, which may complicate monitoring in patients transitioning from DOACs to heparin 3

Common Pitfalls and Caveats

• Do not prematurely discontinue anticoagulation in medically managed patients, as this may increase risk of recurrent ischemic events 2
• When transitioning between different anticoagulants (e.g., from LMWH to UFH), ensure appropriate overlap to maintain therapeutic anticoagulation 4
• For patients with renal impairment, dose adjustment or more frequent monitoring may be necessary when using UFH 5
• In patients with high bleeding risk, consider using bivalirudin alone rather than heparin with glycoprotein IIb/IIIa inhibitors, as this strategy is associated with lower rates of major bleeding while maintaining efficacy 6

Algorithm for Discontinuing Heparin in NSTEMI

1. Determine management strategy (invasive vs. conservative)

2. For invasive strategy with PCI:

   • Discontinue heparin after uncomplicated PCI 1
   • If complications occur, continue anticoagulation as clinically indicated 1

3. For conservative strategy (medical management):

   • Continue UFH for at least 48 hours or until discharge 1
   • Assess for recurrent symptoms/ischemia, heart failure, or serious arrhythmias 1
   • If these complications develop, consider diagnostic angiography 1
   • If no complications develop, discontinue heparin after the minimum 48-hour period 1

4. For patients undergoing CABG:

   • Continue UFH until surgery 1
   • Transition from other anticoagulants to UFH as specified above 1