This research is based on clinic treatment of intravenous thrombolysis for patients with acute ischemic stroke.By building up a database of these patients, the investigators aim to find some significance between groups by analyzing population information, clinical status and such for better evaluation and optimal treatment decision.

With the highest incidence rate,the population in northeast of China is severely tormented by stroke, especially ischemic stroke. The investigators lunch this project by building up a database of detailed information of patients that fits the criteria of intravenous thrombolysis therapy.Including biochemical markers,imaging and follow-up,investigators intend to analysis these data,find factors that contributes to better prognosis,so as to push forward the prevention and control work.

Inclusion Criteria:

1. Diagnosis of ischemic stroke causing measurable neurological deficit
2. Onset of symptoms <4.5 h before treatment begins
3. Age ≥18 y

Exclusion Criteria:

1. Significant head trauma or prior stroke in the previous 3 mo
2. Symptoms suggest SAH
3. Arterial puncture at noncompressible site in previous 7 d
4. History of previous intracranial hemorrhage
5. Intracranial neoplasm, AVM, or aneurysm
6. Recent intracranial or intraspinal surgery
7. Elevated blood pressure (systolic >185 mm Hg or diastolic >110 mm Hg)
8. Active internal bleeding
9. Acute bleeding diathesis, including but not limited to
10. Platelet count <100 000/mm3
11. Heparin received within 48 h resulting in abnormally elevated aPTT above the upper limit of normal
12. Current use of anticoagulant with INR >1.7 or PT >15 s
13. Current use of direct thrombin inhibitors or direct factor Xa inhibitors with elevated sensitive laboratory tests (eg, aPTT, INR, platelet count, ECT, TT, or appropriate factor Xa activity assays)
14. Blood glucose concentration <50 mg/dL (2.7 mmol/L)
15. CT demonstrates multilobar infarction (hypodensity >1/3 cerebral hemisphere)
16. Relative exclusion criteria
17. Recent experience suggests that under some circumstances, with careful consideration and weighting of risk to benefit, patients may receive fibrinolytic therapy despite ≥1 relative contraindications. Consider risk to benefit of intravenous rtPA administration carefully if any of these relative contraindications is present
18. Only minor or rapidly improving stroke symptoms (clearing spontaneously)
19. Pregnancy
20. Seizure at onset with postictal residual neurological impairments
21. Major surgery or serious trauma within previous 14 d
22. Recent gastrointestinal or urinary tract hemorrhage (within previous 21 d)
23. Recent acute myocardial infarction (within previous 3 mo)

Acute ischemic stroke within 4.5h from symptoms onset who received IV rt-PA.