Research On Risk Of Cerebral Infarction Resulting From Carotid Artery Transient Ischemic Attack

Objective: Transient ischemic attack(TIA) as a cerebrovascular disease was common. A large proportion of cerebral infarction was preceded by a transient ischemic attack. Especially, recent TIA that frequently occured was a special alert in cerebral infarction. The purpose of this study was to evaluate the value of adding diffusion-weighted-Imaging(DWI) and magnetic resonance angiography(MRA) to the"ABCD~2"clinical scale for carotid artery TIA to evolve into cerebral infarction within 2-day to 30-day and to investigate the risk factors, aid the clinician in the risk stratification of patients with carotid artery TIA and reduce the incidence of cerebral infarction.Methods: The subjects were hospitalized carotid artery TIA patients in department of neurology of second hospital of HeBei medical university from January 2009 to December 2010. The clinical symptoms, TIA's seizure frequency, duration time, history, clinical data, DWI and MRA findings were recorded in detail. The"ABCD~2"score was applied to all the patients and uesd to analysis the 2-day to 30-day risk of cerebral infarction. In patients with more than one TIA in the past time, the duration of the longest event was used. All patients were followed up at 2 days, 7 days and 30 days after TIA. The aim was to observe the incidence of cerebral infarction.The correlation between"ABCD~2"score and short-term risk of cerebral infarction in carotid artery TIA patients was analyzed by linear regression analysis. The predictive accuracy of the score was quantified by the area under the curve (AUC) of receiver operator characteristic(ROC) curve. Risk factors were compared in different score, DWI and MRA byχ~2 test. The"ABCD~2"score risk factors of the short-time prognosis were analyzed by Logistic regression. P <0.05 was considered statistically significant.Results: 1 The baseline characteristics of patients with carotid artery TIA: 112 of 164 cases were male (68.3%) and 52 were females (31.7%). Age ranged from 19 to 83 years old. The mean age was (55.8±12.20) years. 83 cases had hypertension, 30 cases had diabetes, 3 cases had hyperlipidemia, 10 cases had ischemic heart disease history and history of atrial fibrillation in 1 case. 25 cases had DWI test. 14 cases (56.0%) had DWI abnormalities while 11 cases (44.0%) were DWI normal. 128 patients had MRA test. 45 patients (35.2%) were normal while 83 cases (64.8%) had intracranial artery stenosis. All patients were given medication, hospital stay was 2 to 39 days, the average (13.17±10.02) days. A total of 19(11.6%) patients had cerebral infarction within 2 days after symptoms while 44 (26.8%) patients occurred within 7 days and 54 (32.9%) patients occurred within 30 days. There were no cerebral hemorrhage.2 "ABCD~2" score and the incidence of cerebral infarction of 2 days, 7days and 30 days after carotid artery TIA were positively correlated.With the "ABCD~2" score increased, the incidence of cerebral infarction tended to increase (P <0.05). The AUC of"ABCD~2"score for 2-day,7-day and 30-day were 0.744(P <0.05), 0.751(P<0.001) and 0.736(P<0.001), respectively. The score of 3.5 was the best cut-off. The incidences of cerebral infarction of carotid artery TIA patients with low risk (≤3points), intermediate risk (4 to 5minutes) and high risk (≥6points) were different. The difference was statistically significant (P<0.05).3 The incidences of cerebral infarction were significantly higher in the patients with DWI lesions and intracal arterial stenosis in 2-day, 7-day and 30-day (P<0.05).4 The incidence was significantly higher in carotid artery TIA patients who had unilateral weakness, speech impairment, duration of symptoms≥10 minutes and diabetes in 2 days risk of cerebral infarction (P<0.001); Unilateral weakness, duration of symptoms≥10 minutes and diabetes in patients with carotid artery TIA in 7 days risk of cerebral infarction was significantly higher (P<0.001); Unilateral weakness, duration of symptoms≥10 minutes and diabetes in patients with carotid artery TIA in 30 days risk of cerebral infarction was significantly higher (P<0.001).Conclusion: "ABCD~2" score had predictive value on the incidence of cerebral infarction after carotid artery TIA in short-time. It is a easy way to help clinicians selecting high risk patients and intervene earlier to prevent the occurrence of cerebral infarction. "ABCD~2" scoring with imaging (DWI and MRA) has a higher value.