Resuming Anticoagulation After Hemorrhage

Introduction to Anticoagulation Restart

The American Heart Association recommends restarting anticoagulation at 7-10 days for very high thrombotic risk patients, such as those with mechanical valves or high CHADS2 scores, and at 1-2 weeks for standard risk patients, with a delay of 3-4 weeks or longer for intracranial hemorrhage, particularly lobar bleeds suggesting cerebral amyloid angiopathy 1, 2.

The American College of Cardiology suggests that atrial fibrillation with a CHADS2 score ≥4 points represents very high stroke risk, and anticoagulation should be restarted at 7-10 days after original hemorrhage for mechanical valves or high CHADS2 atrial fibrillation 3, 4.
Patients with lobar location of intracranial hemorrhage are at high risk for cerebral amyloid angiopathy and should wait 3-4 weeks or longer before considering anticoagulation restart 1, 2, 3.

For intracranial hemorrhage, the American Heart Association recommends waiting at least 1-2 weeks before restarting anticoagulation for standard risk patients, and obtaining repeat brain imaging before restart to confirm hemorrhage stability 1, 2, 3.
For gastrointestinal hemorrhage, anticoagulation can be restarted at 1-3 days for very high thrombotic risk patients using parenteral heparin initially, and at 7 days for moderate-low risk patients 5.

The American College of Chest Physicians recommends maintaining INR in the lower end of the therapeutic range when resuming warfarin after intracranial hemorrhage, and using intravenous heparin initially for very high thrombotic risk patients, with advantages including short half-life, easy titration, and rapid reversibility with protamine 2, 5.
Direct oral anticoagulants should not be restarted until at least 7 days after hemorrhage due to their rapid onset of action, and heparin bridging should not be used when initiating direct oral anticoagulants, as this increases bleeding risk 5, 7.

Aspirin should be interrupted for 3 days following hepatic cyst hemorrhage, and restarted at 7-10 days for very high thrombotic risk patients, with the American Heart Association suggesting that antiplatelet use does not dramatically increase hematoma expansion risk and appears generally safe after intracranial hemorrhage, including cerebral amyloid angiopathy cases 1, 3, 7.

Repeat imaging (CT or MRI) should be obtained before restarting anticoagulation to document hemorrhage stability, with the American College of Radiology recommending close monitoring of INR for warfarin and PTT for heparin, and confirmation of no hematoma expansion before proceeding with restart 2, 3, 5.