TIA,RIND, minor stroke: a continuum,or different subgroups? Dutch TIA Study Group.

The results of CT were studied prospectively in 606 patients with a transient ischaemic attack (TIA), 422 patients with a reversible ischaemic neurological deficit (RIND), and 1054 patients with a minor stroke, were all entered into a multi-centre clinical trial. CT scanning showed a relevant ischaemic lesion in 13% (95% confidence interval 10-16%) of TIAs, 35% (95% confidence interval 30-40%) of RINDs, and 49% (95% confidence interval 46-52%) of minor strokes (p less than 0.000001). Even within the 24 hour margin, relevant infarcts occurred more often with longer attacks, but were still found in some patients with attacks lasting less than a minute. The type and location of the infarcts were similar in the three groups. These findings suggest that the differences between TIAs, RINDs, and minor strokes are quantitative rather than qualitative.     

Transient cerebral ischemic attacks in a Japanese community, Hisayama, Japan

During a 20-year follow-up of 1,621 men and women aged 40 and over in Hisayama, Japan, 18 were found to have suffered transient cerebral ischemic attacks (TIAs) determined by clinical symptoms based on criteria proposed by the US Joint Committee for Stroke Facilities. The average annual incidence rate for the first TIA was 0.56 per 1,000 residents. Age and high blood pressure were strong determinants of TIAs for men. Nine of the 18 cases with TIAs (50%) subsequently developed cerebral infarction, an incidence significantly higher than that in the 1,603 subjects without TIAs (10.9%). Lacunar infarcts were most commonly found on pathologic examination of patients with TIAs who had had a subsequent stroke.     

Do transient ischemic attacks have a neuroprotective effect?

OBJECTIVE: To determine whether TIAs have a neuroprotective effect. BACKGROUND: Ischemic tolerance or preconditioning, which protects the brain against stroke, has been demonstrated in animal models of cerebral ischemia. Because TIA may represent a clinical model of ischemic tolerance, patients with TIA before cerebral infarction (CI) may therefore have a better outcome than patients without TIA before CI. METHODS: A total of 2,490 patients admitted consecutively to a primary care center for first-ever CI in the anterior circulation were divided into two groups on the basis of the presence or absence of prior ipsilateral TIAs. Duration of TIA was classified into three groups (<10 minutes, 10 to 20 minutes, and >20 minutes). The severity of the neurologic picture on admission and functional disability after stroke were compared between patients with and without TIAs. RESULTS: A total of 293 (12%) of the 2,490 patients had prior ipsilateral TIAs before CI. Risk factors did not differ between patients with or without TIAs, whereas the topography and etiology of ischemic stroke did differ (p < 0.001). Patients without prior TIAs had a more severe clinical picture on admission, with a greater reduction of consciousness (p = 0.009). Patients with previous TIAs had a more favorable outcome than those without TIAs (67% versus 58%, p = 0.004). After adjustment for confounding variables, TIAs lasting 10 to 20 minutes were still associated with a favorable outcome (odds ratio, 1.98; 95% confidence interval, 1.27 to 3.08; p = 0.002). The interval between TIA and CI influenced the outcome (p = 0.007). CONCLUSIONS: This study suggests that ischemic tolerance may play a role in patients with ipsilateral TIAs before CI, allowing better recovery from a subsequent ischemic stroke.     

Clinical predictors of cardiac and arterial lesions in carotid transient ischemic attacks

In 205 patients with carotid transient ischemic attacks (TIAs) who underwent full angiographic and cardiac investigations, we found that ipsilateral carotid bruit and triggering of TIA by exertion or standing up suggested a carotid lesion. Angina pectoris or palpitations at onset of TIA suggested a cardiac source of emboli. Patients with only one TIA, multiple identical attacks, progression of symptoms over minutes, and appropriate infarct on computed tomograms (28%) were likely to show a potential arterial or cardiac cause for the TIAs in subsequent investigations. Transient monocular blindness correlated with carotid occlusion, but the severity of the carotid lesion did not influence the duration and repetition of attacks. Transient ischemic attacks in multiple territories, identical attacks, and multiple or silent infarcts on computed tomograms occurred equally in the patients with arterial lesions and those with cardiac lesions. These findings suggest that only a few, albeit important, conclusions regarding etiology can be drawn from the clinical characteristics of TIAs.     

The prognosis of carotid siphon stenosis

We retrospectively reviewed the clinical course and angiograms of 15 patients with carotid siphon stenosis of 50% or greater. Fourteen had less than 50% stenosis at the origin of the ipsilateral internal carotid artery, and one had a greater degree of stenosis but underwent endarterectomy after an initial angiogram. Angiograms were examined for evidence of hemodynamic abnormalities in addition to residual lumen diameter. Seven patients initially had TIAs, 5 had strokes, and 3 were asymptomatic. In an average followup of 51 months (range 4-123 months) subsequent cerebral ischemic events occurred in 6 (40%), but only 1 had a stroke with a persisting neurological deficit that could be directly attributed to the siphon stenosis. Stenoses were hemodynamically significant by angiography in 5 of 7 TIA patients, and only 1 of 5 stroke patients. The incidence of subsequent ischemic events in this study was similar to 2 previous studies of siphon stenosis, however in this study most of the events ipsilateral to the siphon stenosis were TIAs or minor strokes. The association of hemodynamic angiographic abnormalities and initial TIAs but not strokes suggests that the mechanism producing ischemic symptoms may differ in patients with TIA and stroke who have carotid siphon stenosis.     

Pattern and frequency of recurrent transient ischemic attacks.

Objectives. Natural history studies and stroke prevention trials in patients with transient ischemic attacks (TIAs) have focused primarily on stroke or death outcomes and not recurrent TIA, yet treatment decisions are often based on recurrences. This study was undertaken to evaluate the frequency and pattern of recurrent TIAs in patients presenting with their first TIA. Methods. We monitored TIA recurrence for an average of 16 months in 47 consecutive patients hospitalized in a tertiary care center within 3 weeks of their first TIA. Treatment in 22 patients was aspirin or ticlopidine alone, and 12 underwent endarterectomy. Remaining patients received warfarin, dipyridamole, or pentoxifylline alone or with aspirin, including two who underwent endarterectomy. Treatment was changed in only four patients during the follow-up period. Results. Thirty-four patients (72%) had more than one TIA; 23 of these (68%) had two to five recurrences and 11 (32%) had more than five TIAs. Nineteen of the 34 patients with multiple TIAs had recurrences within 1 month of the initial TIA. Only four patients (12%) had recurrent TIAs throughout the follow-up period. Stroke occurred in five patients (11%); one patient had a single prior TIA, and the rest had multiple TIAs. No risk factors or treatments predicted which patients had single or multiple TIAs. Conclusions. Most patients have few recurrent TIAs, and recurrences usually occur within the first month of the initial TIA. The patterns of TIA recurrence identified should aid in treating patient and in devising appropriate outcome measures in treatment trials in which TIA is an endpoint.     

Elective stenting for symptomatic middle cerebral artery stenosis presenting as transient ischaemic deficits or stroke attacks: short term arteriographical and clinical outcome

BACKGROUND: Although stent assisted angioplasty is an effective treatment for coronary and peripheral arterial disease, its efficacy in intracranial arteriosclerotic disease has not been verified. OBJECTIVES: To assess the radiographic and clinical outcome of stent assisted angioplasty for symptomatic middle cerebral artery (MCA) stenosis. METHODS: We attempted stent assisted angioplasty in 14 patients with symptomatic high grade stenosis (>60%) on the proximal portion of the MCA, who had experienced either recurrent transient ischaemic attacks (TIAs) resistant to medical therapy or one or more stroke attacks. Patient records were analysed for angiographic characteristics, degree of stenosis, pre-procedural regimen of anti-platelet and/or anti-coagulation agents, use of devices, procedure related complications, pre-operative and post-operative single photon emission computed tomography (SPECT) findings, and clinical and radiographic outcomes. RESULTS: Stent assisted angioplasty was successfully performed in 8 of 14 patients without any serious complications and unsuccessful in 2 of 14 patients due to the tortuous curve of the internal carotid artery siphon. Four patients had complications. Two patients had an arterial rupture; one patient was rescued by an additional stent and balloon tamponade, the other patient died. Complications in the other two patients included thrombotic occlusion and distal thrombosis. Residual stenosis was less than 50% in diameter in all the patients. All eight patients who underwent follow up cerebral angiography had no restenosis. Follow up SPECT showed improved perfusion in the affected MCA territory in all the tested patients with TIA and in one of three stroke patients. Using the modified Rankin Scale at follow up, four of five TIA patients and five of six stroke patients were assessed as functionally improved or having a stable clinical status. CONCLUSION: Although the re-stenosis rate in stent assisted angioplasty seems to be better than in primary balloon angioplasty as reported previously, the complication rate is still high. Elective stenting is an alternative therapeutic method for the prevention of secondary ischaemic stroke in stroke patients with MCA stenosis, and seems to be a potentially effective but also hazardous therapeutic technique in patients with recurrent TIAs. This study indicates the need for randomised control trial data of this intervention. Additionally, long term follow up data and additional clinical experience are required to assess the durability of this procedure.     

Impact of abnormal diffusion-weighted imaging results on short-term outcome following transient ischemic attack

OBJECTIVE: To characterize short-term prognoses among patients with transient ischemic attack (TIA) and normal diffusion-weighted imaging (DWI) results, TIA patients with abnormal DWI results (transient symptoms associated with infarction [TSI]), and patients with completed ischemic stroke (IS). DESIGN: Retrospective study. SETTING: University hospital. PATIENTS: We reviewed patient medical records between January 2003 and December 2004 with International Classification of Diseases, Ninth Revision codes for TIA at admission, resolution of neurological symptoms within 24 hours, magnetic resonance imaging within 48 hours, and a discharge diagnosis of TIA or IS. A random sample of 50 IS patients was selected from all IS admissions and discharges by International Classification of Diseases, Ninth Revision codes. Demographic, clinical, radiographic, and in-hospital outcome data were recorded. Three diagnostic categories were created: TIA with normal DWI results, TSI, and IS. Multivariate logistic regression was used to estimate the association between diagnostic category and rate of in-hospital stroke or recurrent TIA among the 3 groups. RESULTS: We identified 146 classic TIA (25% with TSI) and 50 IS cases. There were 4 recurrent TIAs and 6 strokes among patients with TSI (27.0%); 3 recurrent TIAs and no strokes among patients with normal DWI results (2.8%); and 1 recurrent stroke and no TIAs among IS patients (2.0%). Transient symptoms associated with infarction was independently associated with in-hospital recurrent TIA or stroke (adjusted odds ratio, 11.2; P < .01). CONCLUSIONS: Transient symptoms associated with infarction is associated with a greater rate of early recurrent TIA and stroke than both IS and TIA with normal DWI results. These data suggest that TSI may be a separate clinical entity with unique prognostic implications.     

Bilateral occlusion of the trunk of the middle cerebral artery. Results of an international randomized trial. The EC/IC Bypass Study Group

Bilateral occlusion of the middle cerebral artery (MCA) trunk theoretically should be a very severe condition, but its actual prognosis has never been studied. Nine of 1,377 patients (7 Asians, 1 Black, 1 Caucasian) from the Cooperative Study of Extracranial/Intracranial Arterial Anastomosis were found to have atherosclerotic bilateral occlusion of the middle cerebral artery (MCA) trunk before entering the trial. Three presented with a stroke followed by a contralateral stroke, two experienced a unilateral stroke, two had a unilateral stroke preceded by ipsilateral TIAs, one had a unilateral stroke preceded by TIAs on both sides and one experienced isolated unilateral TIAs. Retrograde filling to the distal MCA was universally present. During follow-up (mean: 45 months), only one (non-operated) patient had further cerebrovascular events, and ultimately a fatal stroke. One additional patient died of sepsis and one had a silent myocardial infarct. All survivors resumed their previous activities. This study shows that in bilateral MCA trunk occlusion, the long-term prognosis is reasonable in the patients who do not present with a devastating stroke.     

Occlusive disease of the middle cerebral artery

We studied 20 patients with severe occlusive disease of the mainstem middle cerebral artery (MCA) or its major division branches, and 25 patients with internal carotid artery (ICA) disease. MCA disease patients were more often black, female, younger, and had fewer TIAs than the ICA disease patients. Neurologic signs in patients with MCA disease evolved progressively during days to weeks, whereas ICA disease patients more often had an acute onset of nonprogressive deficits. CT commonly showed restricted subcortical or wedge-shaped infarcts in MCA disease patients. All MCA disease patients had stroke, but 40% of ICA disease patients had no infarction. MCA lesions usually affected the mainstem MCA or its major superior division. Patients with MCA disease seldom had recurrent ischemia in the same vascular territory as the stroke and had a low incidence of subsequent cardiac death.     

Clinical characteristics of transient ischemic attacks in black patients

We analyzed the clinical, CT, and angiographic findings in 50 black patients with carotid transient ischemic attacks (TIAs). Thirty-two percent had TIAs lasting less than 1 hour, 26% had TIAs lasting 1 to 6 hours, and 42% had TIAs lasting 6 to 24 hours. Fifty-two percent of TIA patients had CT evidence of cerebral infarction despite complete clinical recovery. CT was abnormal in two of 16 (13%) patients with TIAs lasting less than 1 hour; however, CT was abnormal in 24 of 34 (70%) patients with TIAs lasting longer than 1 hour. Angiographic findings of extracranial carotid disease appropriate to TIA symptoms were present in 12 (24%) patients. Two patients in whom the TIA episode lasted less than 1 hour later had clinical cerebral infarction, whereas 20 patients with longer-duration TIAs developed ischemic stroke within 4 months. Of these black TIA patients, 22 (44%) developed clinical cerebral infarction.     

大脑中动脉狭窄与其深穿支供血区单发脑梗死的关系

目的 分析大脑中动脉(MCA)深穿支供血区单发脑梗死的形态学表现,进一步探讨其与MCA狭窄的关系.方法 连续入选2005年1月至2006年12月于北京协和医院神经科住院治疗急性脑梗死,并经头颅DWI检查明确急性梗死灶为单发,且位于MCA深穿支供血区域的55例患者;所有患者均行TCD和MRA检查,颅外颈内动脉狭窄>50%以及有可疑心源性栓子来源的患者从研究中排除.根据是否存在病灶同侧MCA狭窄将入选患者分为两组:MCA狭窄组(14例)与MCA正常组(41例).测量DWI上急性梗死灶的直径、面积和体积,并将直径≤2 cm归为经典腔隙性梗死,直径>2 cm归为纹状体内囊梗死.DWI上的梗死灶区分为基底节区、侧脑室体旁和同时累及上述2个部位,并判断MRI T2>像上皮质下多发陈旧性小梗死灶或白质疏松是否存在.结果 55例患者中,病灶侧MCA狭窄患者14例(25.5%),MCA正常患者41例(74.5%).MCA狭窄组中经典腔隙性梗死占71.4%,MCA正常组中经典腔隙性梗死占67.3%,差异无统计学意义(χ2=0.147,P=0.701).MCA狭窄组与正常组患者MCA深穿支梗死病灶的大小(包括直径、面积及体积)差异均无统计学意义.MCA正常组和MCA狭窄组病灶在基底节区、侧脑室体旁及基底节区+侧脑室体旁分布的比例依次为:正常组31.7%、17.1%和51.2%;狭窄组35.7%、28.6%和35.7%,两组间差异无统计学意义(χ2=1.272,P=0.529).同时存在皮质下多发陈旧性小梗死灶或白质疏松的患者在MCA正常组有23例(56.1%),在MCA狭窄组有3例(21.4%),二者差异有统计学意义(χ2=5.033,P=0.025).结论 MCA深穿支供血区梗死具有不同的发病机制,MCA狭窄和穿支动脉本身病变均可造成深穿支供血区单发脑梗死.梗死灶的大小、体积及梗死发生的部位与是否存在同侧大脑中动脉狭窄无明显相关性,而同时存在皮质下多发陈旧性小梗死灶或白质疏松对穿支动脉病变有提示作用.     

Incidence and predictive factors of cerebrovascular events in 8,846 elderly treated hypertensive patients during a 3-year follow-up: the PRESAGE study

This epidemiological study was carried out as a 3-year follow-up project to assess the incidence of transient ischemic attacks (TIAs) and strokes; 8,846 treated hypertensive patients (mean BP, 149/84 mm Hg) aged 65 years or over (mean age, 73.7 +/- 6.3 years), devoid of symptoms of dementia and with documented vascular risk factors were recruited from January 1994 to August 1995, by 1,598 general practitioners in connection with 36 referral university neurology units throughout metropolitan France. Among these patients, 506 (5.7%) had at least one cerebrovascular event during the follow-up period: 309 (3.5%) experienced one or more isolated TIAs, and 197 (2.2%) had a stroke with or without a preceding TIA. A total of 510 TIAs were reported. The stroke subtypes were ischemia, hemorrhage, and unclassified in 70, 16, and 15% of the cases, respectively. The estimated annual stroke incidence was 7.42 per thousand. Of the 197 patients who developed strokes, 51 (26%) died. This case-fatality rate should be compared with the 4.5% mortality rate observed in the whole population during the study period. The 3 subgroups (with isolated TIAs, strokes, or no events during the study) were found to differ regarding age, sedentary lifestyle, past history of cardiovascular events, duration of hypertension, and evidence of complicated hypertension (univariate analysis). The factors identified as predictive of a stroke (multivariate analysis) were: the patient's age; sedentary lifestyle; pulse pressure (SBP-DBP); identification of TIA at baseline, and presence of arrhythmias.     

大脑中动脉分布区缺血性卒中患者的临床和影像学特征及复发危险因素

目的 分析大脑中动脉（middle cerebral artery,MCA）分布区非心源性缺血性卒中患者的临床和影像 学特征及复发的危险因素。 方法 连续入选发病7 d以内的MCA分布区非心源性缺血性卒中患者。收集患者的人口学信息、血管 病的危险因素和发病时的主要症状及体征,评价患者的头颅磁共振影像包括急性梗死灶的部位、 数量、分布特征、责任动脉有无狭窄、缺血性卒中的病因分型。随访患者1年内有无缺血性卒中或短暂 性脑缺血发作（transient ischemic attack,TIA）复发,通过多元Logistic回归分析患者复发的危险因素。 结果 研究共入组926例患者,责任MCA狭窄≥70%的患者（447例）常见多发梗死灶（338例,75.6%） 和分水岭梗死（317例,70.9%）,而责任MCA无狭窄或狭窄程度<70%患者（479例）常见MCA穿支分 布区单发梗死灶（247例,55.3%）。冠状动脉粥样硬化性心脏病[比值比（odds ratio,OR）7.55,95%可 信区间（confidence interval,CI）2.85～20.0,P <0.001]、缺血性卒中病史（OR 3.49,95%CI 1.52～8.01, P =0.003）、缺血性卒中发病前3个月内反复TI A史（OR 22.7,95%CI 8.35～61.6,P <0.001）、新发梗死 灶为多发（OR 5.26,95%CI 1.33～20.8,P =0.018）是患者1年内缺血性卒中或TIA复发的危险因素。 结论 对于非心源性缺血性卒中患者,MCA分布区梗死灶的分布特征与MCA狭窄程度有关。新发梗 死灶为多发、既往有缺血性心脑血管病病史的患者1年缺血性卒中或TIA复发风险高。     

Neurovascular territory involved in different etiological subtypes of ischemic stroke in the Perugia Stroke Registry

We studied the correlation between the potential causes of stroke (TOAST etiological groups) and the involvement of different vascular territories seen on computed tomography (CT) scans in patients with ischemic stroke. Information from consecutive patients with a first-ever stroke have been prospectively coded and entered into a computerized data bank (Perugia Stroke Registry). A population of 1,719 patients were evaluated: 1,284 patients (74.7%) had ischemic stroke. Large artery disease was the main cause of entire middle cerebral artery (MCA) territory infarcts (40.9%), superficial MCA territory infarcts (35.7%), and watershed infarcts (68.2%). The highest presence of emboligenic heart disease was found in the entire MCA territory infarcts (28.8%) or superficial (29.4%) supratentorial infarcts and in cerebellar infarcts (36.8%). Small artery disease was the most common presumed cause of deep MCA infarcts (75.0%) and posterior cerebral artery (PCA) territory infarcts (52.1%). In conclusion: stroke location could depend on its etiology. Lacunar infarcts are the most prevalent (36.7%), being mostly localized in the deep MCA territory; large artery disease includes more than two-thirds of watershed infarcts; the most prevalent territories involved in cardioembolic stroke are the entire MCA and posterior fossa.     

Cerebrovascular and neurologic disease associated with antiphospholipid antibodies: 48 cases

Lupus anticoagulants and anticardiolipin antibodies are antiphospholipid antibodies (APLAb) with related antigenic specificities and are newly recognized markers for an increased risk of thrombosis. We studied 48 patients who presented with cerebral or visual dysfunction associated with APLAb to help clarify the diagnostic, clinical, laboratory, radiologic, and pathologic features in these patients. Most patients presented with transient cerebral ischemia or cerebral infarction. Recurrent and stereotypic events were frequent. Visual disturbances resulted from amaurosis fugax, retinal arterial or venous occlusion, occipital ischemia, diplopia, and migraine-like disturbances. Three patients presented with severe atypical classic migraine. Recurrent infarcts of brain and eye were significantly associated with the presence of cigarette smoking, hyperlipidemia, and a positive antinuclear antibody. During 44.4 patient-years of prospective follow-up, the combined stroke and systemic thrombotic event rate was 0.27 events per patient-year and was 0.54 events per patient-year if TIA and death were included. Forty (83%) of the patients did not have systemic lupus erythematosus (SLE). Thrombocytopenia was present in 15 (31%) and a false-positive VDRL in 11 (23%) of the patients. Cerebral angiography was normal or revealed large-vessel occlusion or stenosis without changes suggestive of vasculitis. Patients with only transient dysfunction generally had normal radiologic studies, including angiography. Organs and arterial vessels studied pathologically revealed thrombotic occlusive disease without vasculitis. APLAb are strongly associated with an immune-mediated thrombotic tendency, generally in the absence of SLE. Other stroke risk factors may add to the risk of recurrent ischemic events in patients with APLAb.     

Longitudinal thalamic diffusion changes after middle cerebral artery infarcts

BACKGROUND: Cerebral infarcts are responsible for functional alterations and microscopic tissue damage at distance from the ischaemic area. Such remote effects have been involved in stroke recovery. Thalamic hypometabolism is related to motor recovery in middle cerebral artery (MCA) infarcts but little is known concerning the tissue changes underlying these metabolic changes. Diffusion tensor imaging (DTI) is highly sensitive to microstructural tissue alterations and can be used to quantify in vivo the longitudinal microscopic tissue changes occurring in the thalamus after MCA infarcts in humans. METHODS: Nine patients underwent DTI after an isolated MCA infarct. Mean diffusivity (MD), fractional anisotropy (FA), and thalamic region volume were measured from the first week to the sixth month after stroke onset in these patients and in 10 age matched controls. RESULTS: MD significantly increased in the ipsilateral thalamus between the first and the sixth month (0.766 x 10(-3) mm(2)/s first month; 0.792 x 10(-3) mm(2)/s third month; 0.806 x 10(-3) mm(2)/s sixth month). No significant modification of FA was detected. In six patients, the ipsilateral/contralateral index of MD was higher than the upper limit of the 95% CI calculated in 10 age matched controls. An early decrease of MD preceded the increase of ipsilateral thalamic diffusion in one patient at the first week and in two other patients at the first month. CONCLUSION: After MCA infarcts, an increase in diffusion is observed with DTI in the ipsilateral thalamus later than 1 month after the stroke onset. This is presumably because of the progressive loss of neurons and/or glial cells. In some patients, this increase is preceded by a transient decrease in diffusion possibly related to an early swelling of these cells or to microglial activation. Further studies in larger series are needed to assess the clinical correlates of these findings.     

Outcome of patients with cryptogenic stroke and patent foramen ovale

OBJECTIVES: The aim was to estimate the recurrence rate and to define subgroups at increased risk for recurrent cerebral ischaemia in patients with patent foramen ovale (PFO) and so called cryptogenic stroke due to paradoxical embolism. METHODS: Patent foramen ovale was diagnosed in 318 patients with otherwise unexplained ischaemic stroke or transient ischaemic attack (TIA). One hundred and fifty nine were treated medically (oral anticoagulation 79, platelet inhibitors 80) and represent the study population. The remaining 159 patients underwent endovascular or surgical closure of the PFO and are not part of this study. RESULTS: Mean age was 50.7 (SD 13.5) years. The event leading to the diagnosis of PFO was a TIA in 38 patients (23.9%), an ischaemic stroke in 119 (74.8%), and an amaurosis fugax in two patients (1.3%). Forty four patients (27.7%) had experienced multiple cerebrovascular ischaemic events before the diagnosis of the PFO. During mean follow up of 29 (SD 23) months 21 patients (13.4%) had a recurrent cerebrovascular event (seven strokes and 14 TIAs). The average annual rate of recurrent strokes was 1.8% and that of recurrent strokes or TIAs was 5.5%. When patients with PFO with multiple cerebrovascular events before the diagnosis of the PFO were analyzed separately, the average annual rates of recurrent cerebral ischaemia were 3.6% for recurrent strokes and 9.9% for recurrent strokes or TIAs. These rates were significantly higher than in patients with first ever stroke or TIA (p=0.02). CONCLUSIONS: The study confirms a risk of stroke recurrence that is similar to the rates of previously published series of patients with PFO and cryptogenic strokes. Patients with more than one previous event were at increased risk of recurrent cerebral ischaemia.     

Recurrent brain hemorrhage is more frequent than ischemic stroke after intracranial hemorrhage

OBJECTIVE: To characterize the rates of recurrent intracranial hemorrhage (ICH), ischemic stroke, and death in survivors of primary ICH. METHODS: Systematic review of studies reporting recurrent stroke in survivors of primary ICH, identified at index ICH and followed forward. Studies were identified by computerized search of the literature and review of reference lists. RESULTS: Ten studies published between 1982 and 2000 reporting 1,880 survivors of ICH, followed for a total of 6,326 patient-years (mean follow-up, 3.4 patient-years), were included. The aggregate rate of all stroke from five studies was 4.3% per patient-year (95% CI, 3.5% to 5.4%). The rate in the three population-based studies was higher than in the two hospital-based studies, 6.2% versus 4.0% per patient-year (p = 0.04). About three fourths of recurrent strokes were ICH. Considering all 10 studies, a total of 147 patients had a recurrent ICH, an aggregate rate of 2.3% per patient-year (95% CI, 1.9% to 2.7%). Based on data from four studies, patients with a primary lobar ICH had a higher rate of recurrent ICH than those with a deep, hemispheric ICH (4.4% versus 2.1% per patient-year; p = 0.002). The aggregate rates of subsequent ischemic stroke and mortality were 1.1% per patient-year (95% CI, 0.8% to 1.7%) and 8.8% per patient-year (95% CI, 5.2% to 11.0%). CONCLUSIONS: Recurrent stroke among survivors of primary ICH occurs at a rate of about 4% per patient-year, and most are recurrent ICH. Survivors of ICH have a higher risk of recurrent ICH than of ischemic stroke, and this has implications for the use of antithrombotic agents in these patients.     

Blood flow reactivity to hypercapnia in strictly unilateral carotid disease: preliminary results.

To show relationship between degree of carotid arterial stenosis and cerebral blood flow reactivity (RES%) to induced hypercapnia, fluorine-18-fluoromethane and positron emission tomography (PET) was used to study 18 patients with carotid distribution transient ischaemic attacks (TIA), all free of stroke, who had angiographic-proven unilateral arterial disease. Non-involved carotid arteries were either normal or had non-stenotic plaque. Either normal arteries or nonstenotic ulcerations in the symptomatic carotid arteries were present in five of 18 (28%), ipsilateral carotid stenosis from 50-99% was present in eight of 18 (44%), and ipsilateral internal carotid occlusion was present in five of 18 (28%) patients. In comparison with 14 normal controls, all patients with symptomatic middle cerebral artery (MCA) flow territories had significantly lower mean (SEM) RES% [5.0' (0.2) vs 4.0 (0.9), p less than 0.04]. Symptomatic anterior borderzone (ABZ) RES% was also significantly lower [4.6 (0.4) vs 3.3 (0.9), p less than 0.04], than controls. In patient subgroup comparisons, the 50-99% stenosis subgroup clearly had the lowest MCA RES% [3.4 (0.2)] as well as the lowest ABZ RES% [2.8 (0.4)] on their symptomatic sides. Age, expired pCO2, mean arterial blood pressure, serum glucose, serum haematocrit and number, type and estimated duration of TIAs were not significantly different between subgroups. Linear regression showed a significant relationship between RES% and both measured percentage-stenosis (p = 0.04) and residual luminal diameter (p = 0.05) in symptomatic MCA territories. This approached significance in symptomatic ABZ regions. This preliminary data set suggests that unilateral carotid stenosis can and does result in impaired CO2 reactivity following hypercapnia. The relative normality of CO2 reactivity in those with carotid occlusion is discussed.