Restarting Early Versus Later Anticoagulation for Chronic Subdural Hematoma With Atrial Fibrillation

Restarting Early Versus Later Anticoagulation for Chronic Subdural Hematoma With Atrial Fibrillation (RELACS): An International Multicenter, Randomized Controlled, Two-arm, Assessor-blinded, Trial

The goal of this randomized clinical trial is to assess the benefit of early resumption versus late resumption of oral anticoagulation medication in adults with atrial fibrillation undergoing surgery for chronic subdural hematoma. The main questions it aims to answer are:

• Does anticoagulation resumption 5 days after surgery as compared to 30 days after surgery result in fewer thromboembolic complications, without increasing the risk for bleeding?
• Does anticoagulation resumption 5 days after surgery as compared to 30 days after surgery affect the risk of reoperation, functional outcome, mortality, and healthcare use?

Researchers will compare early anticoagulation resumption (5 days) and late anticoagulation resumption (30 days) after chronic subdural hematoma surgery.

Participants will either resume the medication 5 days or 30 days after the surgery. The participants will be followed up for 3 months after the surgery.

Inclusion Criteria:

• Age ≥18 years.
• Patients with a symptomatic unilateral or bilateral CSDH requiring burr-hole evacuation with drainage (CSDH is predominantly hypodense or isodense on imaging [CT/MRI]; clinical symptoms attributable to the CSDH; patients with bilaterally operated CSDHs will be treated with the same protocol on both sides and analyzed as a single study participant).
• Patients that are on an oral anticoagulation medication due to permanent, persistent or paroxysmal spontaneous atrial fibrillation previously known
• Randomization done within 4 days of the surgery

Exclusion Criteria:

• Intraoperative or immediate postoperative hemorrhagic complication
• CSDH requiring surgical treatment other than burr-hole evacuation (e.g. craniotomy)
• Prior CSDH surgery within 12 months
• Cerebrospinal fluid shunt
• CSDH is in an arachnoid cyst
• If the operated hematoma is revealed to be a cerebrospinal fluid collection (hygroma)
• Conditions other than atrial fibrillation that require anticoagulation, including therapeutical dose of low molecular-weight heparin or heparin (for example, pulmonary embolism, deep vein thrombosis, hypercoagulability syndromes)
• Mechanical heart valve(s)
• Moderate or severe mitral stenosis (other valvular diseases and biological valves are eligible)
• Contraindication to anticoagulation medication (for example bleeding disorder, documented high risk of fall [e.g. due to severe alcoholism], severe thrombocytopenia, severe anemia)
• Concomitant use of antiplatelet medication
• Moderate to severe renal insufficiency (creatinine clearance <30 ml/min or on dialysis)
• Not a permanent resident in Finland (for Finnish patients) or not a permanent resident in Region Stockholm (for Swedish patients)