Inclusion Criteria:  Acute subarachnoid hemorrhage due to an intracranial ruptured aneurysm. Diagnosis must be done with acute CT or MRI. Intracranial saccular aneurysm with neck diameter 2-11mm and neck-dome height ≥2 mm. Clinical severity measured by World Federation Neurological Surgeons scale score ≤ III. Age ≥18 years. Previous modified Rankin scale ≤2. Informed consent obtained from the patient or acceptable patient surrogate.  Exclusion Criteria:  Hemodynamically unstable patients with requirement of advanced vital support. Patients with limited life expectancy (<6 months) due to terminal disease. Previous antiplatelet or anticoagulation treatment. Participation in any other clinical trial with a drug or device which could influence the outcome. Patients with neurological or psychiatric disease that could undermine future evaluations. Lack of availability for 12 months tracing.