频发短暂性脑缺血发作与颅内外血管病变的相关性

Relation between frequent transient ischemic attacks and intracranial or extracranial artery lesions

目的探讨症状相关侧血管狭窄程度、颈动脉斑块性质与频发短暂性脑缺血发作（TIA）的相关性。方法应用DSA和颈动脉超声、经颅彩色多普勒超声联合对79例急性期（7d内）颈内动脉系统TIA患者进行检查，按照患者首次发作至入院当天（时间范围≤7d）的TIA发作次数分为TIA缓解组（发作次数〈3次）和TIA频发组（发作次数≥3次），比较两组間症状相关侧血管狭窄程度、颈动脉斑块性质的差异。结果颈内动脉系统TIA患者的血管病变以颅内病变为主，以大脑中动脉病变最为多见（51．2％），颈内动脉颅外段次之（37．2％）。TIA频发组与TIA缓解组相比，发作时间短暂（≤10min），两组差异有统计学意义（X^2=5．343，P=0．021）。TIA频发组症状相关侧血管1〉50％狭窄比例（66．7％）明显高于TIA缓解组（35．3％,x^2=7．655，P=0．006）。症状相关侧颈动脉斑块性质与频发TIA无相关性（x^2=0．939，P=0．332）。结论频发TIA发作时间短暂且与症状相关侧血管中重度狭窄（≥150％）相关，其发病机制可能主要与血流动力学因素有关。

Objective To investigate the relationship between the stenosis of clinically relevant artery or the characteristics of carotid plaques and frequent transient ischemic attacks （TIA）. Methods Seventy-nine consecutive patients suffered TIA attribute to carotid territory in the acute phase（ within 7 days） who had been admitted to neurology department of Xuanwu Hospital from August 2005 to January 2007 were retrospectively analyzed. Patients with nonatherosclerotic vascular disease were excluded. According to the times of TIA from the first attack to the day of hospitaliztion （within 7 days） patients were divided into two groups： those who had sparse TIA （onsets 〈 3 times）, and those who had multiple TIA （onsets ≥3 times）. All patients underwent the examination of DSA, carotid ultrasound and transcranial doppler. The degree of stenosis of clinically relevant artery and the characteristics of carotid plaques were compared between the two groups. According to degree of stenosis of relevant artery, we defined as normal or 〈 50% stenosis, 50%- 69% stenosis, 70%-99% stenosis or occlusion. According to the characteristics of carotid plaques we divided into stable or unstable plaques. Results Patients with TIA in carotid territory had more intracranial artery diseases. The middle cerebral artery was the most commonly involved artery （51.2%）, the extracranial internal carotid artery was the next （ 37. 2% ）. Multiple TIA were more likely to have a short duration of symptoms ≤ 10 min than sparse TIA （X^2 = 5. 343, P = 0. 021 ）. A significant stenosis of clinically relevant artery（ 1〉50% ） was demonstrated more frequently in the multiple TIA group（66.7% ） than in the sparse TIA group （35.3%, X^2 =7. 655, P =0. 006）. No significant correlation was observed between the multiple TIA and characteristics of carotid plaques in the focus side （x^2 = 0. 939, P = 0. 332）. Conclusions Frequent TIA is significantly associated with a short duration of symptoms and ≥50% stenosis of clinically relevant artery. Transient flow reduction by hemodynamic compromise may be an important mechanism of frequent TIA.