Acute ischemic stroke (AIS) is the most common type of stroke, which has high rate of morbidity, mortality and disability. A large number of studies have confirmed that the thrombolytic therapy can effectively open blood vessels and improve the functional prognosis of acute ischemic stroke. Therefore, all guidelines recommend giving thrombolysis treatment to acute ischemic stroke patients within 4.5 hours of onset. However, about 1/3 patients receiving thrombolysis will have good prognosis, while a large number of patients will still be disabled and even dead. How to improve the neurofunctional prognosis of thrombolytic patients has been a hot topic in the world.

Butyl phthalide is type I chemical drugs. Some multicenter randomized, double-blind, placebo-controlled clinical trials have showed that acute ischemic stroke patients taking butyl phthalide has better lateral branch circulation and living ability score than patients taking placebo. Besides, butyl phthalide treatment is safe. The animal experiment indicated that buphthalein could significantly improve secondary side branch circulation, recover the microarterial diameter of the soft meninges in the ischemic region and increase the blood flow rate.

Based on the discussion, we assume that: giving butyl phthalide to patients with acute ischemic stroke in advance, might promote and improve the formation of collateral circulation to freeze ischemia penumbra. Based on this hypothesis, we would like to explore the efficacy and safety of butyl phthalide combined with rtPA thrombolysis in the treatment of acute ischemic stroke.

Inclusion Criteria:

1. Age >18 years;
2. Diagnosis of anterior circulation infarct;
3. First stroke onset or past stroke without obvious neurological deficit (mRS≤1);
4. Time from onset to treatment ≤4.5 hours;
5. SBP/DBP ≤ 180/110mmHg;
6. No hemorrhagic imaging changes showed in CT;
7. Signed informed consent by patient self or legally authorized representatives.

Exclusion Criteria:

1. History of stroke within 3 months;
2. History of intracranial hemorrhage;
3. Suspected subarachnoid hemorrhage;
4. Intracranial tumour, vascular malformation or arterial aneurysm;
5. Major surgery within 1 month;
6. Systolic pressure ≥180 mmHg or diastolic pressure ≥110 mmHg;
7. Platelet count < 100×109／L;
8. Heparin therapy or oral anticoagulation therapy within 48 hours;
9. Severe disease with a life expectancy of less than 3 months;
10. Blood glucose < 50 mg/dL (2.7mmol/L);
11. Patients who have received any other investigational drug or device within 3 months;
12. Researchers consider patients inappropriate to participate in the registry. -