Stroke rates in patients with lacunar and large vessel cerebral infarctions

Blood flow velocities of cerebral arteries in lacunar infarction and other ischemic strokes

Blood flow velocity is an important determinant of vascular hemodynamics. The aim of the present study was to determine the mean flow velocities (MFVs) of cerebral arteries in patients with ischemic stroke, comparing lacunar and nonlacunar infarctions. 388 consecutive patients were examined for lacunar infarction, other subtypes of ischemic stroke, and the presence of underlying internal carotid artery steno-occlusion (ICS). MFVs were measured using transcranial Doppler along the full segments of each cerebral artery including both right and left middle cerebral arteries, basilar artery, and both of the vertebral arteries. The patients were categorized into two major groups: lacunar infarction, and nonlacunar infarction with or without underlying ICS. The characteristics of patients with lacunar infarction (n=83, 21.4%) were significantly different from those with nonlacunar infarctions: younger age, lower prevalence of type 2 diabetes, and lower concentration of plasma total homocysteine. The patients with lacunar infarction had lower MFVs in cerebral arteries than the patients with nonlacunar infarctions, especially in the posterior circulation vessels such as the basilar artery and both vertebral arteries. Different hemodynamics might be pathophysiologically associated with the lacunar infarction, compared with the other subtypes of ischemic stroke.

Decision analysis and carotid endarterectomy

A data base and a framework for clinical decision analysis are provided to enable the clinician to determine the value of carotid endarterectomy in patients with transient ischemic attacks. This approach permits optimal utilization of available data, maximizes the value of informed consent by clearly delineating areas of physician and patient expertise, and permits a quantitative assessment of the impact of uncertainty regarding underlying variables on decision outcome. The results of the analysis indicate that (a) the late nonstroke death rate has little effect on the value of endarterectomy, (b) the patient's relative valuation of stroke and immediate versus delayed death are among the most crucial variables underlying the value of endarterectomy, and (c) endarterectomy may be indicated in certain patients with transient ischemic attacks, but when its utility is measured in terms of value rendered to the patient, its relative cost may be greater than that of certain life-saving operations such as heart or liver transplant.

Differences Between Ischemic Stroke Subtypes in Vascular Outcomes Support a Distinct Lacunar Ischemic Stroke Arteriopathy

Background and Purpose— Whether and how the arterial pathology underlying lacunar ischemic stroke differs from the atherothrombotic processes causing most other ischemic strokes is still debated. Different risks of recurrent stroke and MI after lacunar versus nonlacunar ischemic stroke may support a distinct lacunar arteriopathy.

Methods— We prospectively followed a hospital-based cohort of 809 first-ever ischemic stroke patients for 1 to 4 years. We compared risks of death, recurrent stroke, and MI in patients with lacunar versus nonlacunar stroke, and performed an updated meta-analysis of recurrent stroke subtype patterns.

Results— During 1725 person-years of follow-up, 109 patients had a recurrent stroke and 31 had MI. All patients at baseline, and 93% with recurrent stroke, had brain imaging and more than half with recurrent stroke had diffusion-weighted MRI. Overall, there was no difference in recurrence risk after lacunar vs nonlacunar stroke, although there was a trend toward a lower recurrence risk in the early weeks after lacunar stroke. Lacunar recurrence was more likely after lacunar than nonlacunar stroke (OR, 6.5; 95% CI, 2.4–17.5; updated meta-analysis OR, 6.8; 95% CI, 4.2–11.2). MI risk was nonsignificantly lower after lacunar than nonlacunar stroke (rate ratio, 0.5; 95% CI, 0.2–1.1; rate ratio after excluding patients with previous ischemic heart disease: 0.3; 95% CI, 0.1–0.9).

Conclusions— Our finding of a trend toward a lower MI risk after lacunar vs nonlacunar stroke and confirmation of both a lower early recurrence risk after lacunar stroke and a tendency of recurrent stroke subtypes to “breed true” support the notion of a distinct nonatherothrombotic lacunar arteriopathy.

Large Subcortical Infarcts

BACKGROUND AND PURPOSE

In this study we compared risk factors, clinical features, and stroke recurrence in a large series of patients with large subcortical, cortical, or small deep infarcts.

METHODS

Patients with a transient or minor ischemic attack (modified Rankin Scale grade of < or =3) who had a single relevant supratentorial infarct of presumed noncardioembolic origin on CT were classified as suffering from a large subcortical (n=120), small deep (n=324), or cortical (n=211) infarct. Mean follow-up was 8 years. Rates of recurrent stroke were compared with Cox regression.

RESULTS

The clinical deficits caused by large subcortical infarcts resembled either those of a cortical or those of a small deep infarct. Risk factor profiles were similar in the 3 groups. The rate of recurrent stroke in patients with a large subcortical infarct (25/120; 21%) did not differ from that of patients with a cortical infarct (46/211; 22%) or with a small deep infarct (60/324; 19%). After adjustment for age, sex, and vascular risk factors, hazard ratios for recurrent stroke of large subcortical and cortical infarcts were 1.05 (95% CI, 0.65 to 1.70) and 1.17 (95% CI, 0.79 to 1.73), respectively, compared with small deep infarcts.

CONCLUSIONS

Clinical features, risk factor profiles, and stroke recurrence rate in patients with a large subcortical infarct only differ slightly from those in patients with small deep or cortical infarcts.

Comparing risks of death and recurrent vascular events between lacunar and non-lacunar infarction

Differences in prognosis of lacunar and non-lacunar infarction patients might support distinct arterial pathological processes underlying these two subtypes of ischaemic stroke. We performed a systematic review in which we identified cohort studies with ischaemic stroke subtype-specific follow-up data on death, recurrent stroke and/or myocardial infarction (MI). We calculated risks of death and recurrent stroke at 1 month, 1-12 months and 1-5 years, as well as risks of MI and cardiac death. We compared non-lacunar with lacunar infarction, using study-specific and summary odds ratios. We also compared the pattern of recurrent stroke subtypes after lacunar and non-lacunar infarction. One month odds of death and of recurrent stroke were significantly greater following non-lacunar than lacunar infarction, but the difference decreased thereafter (1 month mortality: OR 3.81, 95% CI 2.77-5.23; 1-12 month mortality: OR 2.32, 95% CI 1.74-3.08; 1-5 year mortality: OR 1.77, 95% CI 1.28-2.45; 1 month stroke recurrence: OR 2.11, 95% CI 1.20-3.69; 1-12 month stroke recurrence: OR 1.24, 95% CI 0.85-1.83; 1-5 year stroke recurrence: OR 1.61, 95% CI 0.96-2.70). Recurrent strokes were more likely to be lacunar if the index event was lacunar. Few studies reported on the risk of MI, but we found no significant difference in risk of cardiac death in non-lacunar versus lacunar infarction. Thus, although early mortality and stroke recurrence risks are higher among non-lacunar than lacunar infarct patients, the risks appear not to differ in the longer term and the risks of cardiac outcomes are similar, although data are limited. There is some evidence that recurrent ischaemic stroke subtypes breed true. These results provide limited support for a distinct arterial pathology underlying lacunar infarction.

Ten year recurrence after first ever stroke in a Japanese community: the Hisayama study

BACKGROUND

Very few population based cohort studies have focused on the long term recurrence of stroke.

OBJECTIVE

To examine 10 year cumulative recurrence rates for stroke in a Japanese cohort according to pathological type and clinical subtype of brain infarction.

METHODS

During a 32 year follow up of 1621 subjects >/=40 years of age, 410 developed first ever stroke. These were followed up prospectively for 10 years after stroke onset.

RESULTS

During follow up, 108 (26%) experienced recurrent stroke. The cumulative recurrence rates were 35.3% at five years and 51.3% at 10 years. The 10 year recurrence rates of subarachnoid haemorrhage (SAH), brain haemorrhage, and brain infarction were 70.0%, 55.6%, and 49.7%, respectively; the difference between SAH and brain infarction was significant (p = 0.004). Most recurrent episodes after SAH or brain haemorrhage happened within a year after the index stroke, whereas recurrence of brain infarction increased consistently throughout the observation period. Cardioembolic stroke had a higher recurrence rate (75.2%) than lacunar infarction (46.8%) (p = 0.049). The 10 year risk of stroke recurrence increased with age after lacunar or atherothrombotic brain infarction, but not after the other types or subtypes. After atherothrombotic brain infarction, cardioembolic stroke, or SAH, the type and subtype of most recurrent strokes were the same as for the index stroke, but recurrence after lacunar infarction or brain haemorrhage showed divergent patterns.

CONCLUSIONS

Japanese people have higher recurrence rates of stroke than other populations. Recurrence rate after a first brain infarct increases consistently through the next 10 years.

Cause of stroke recurrence is multifactorial: patterns, risk factors, and outcomes of stroke recurrence in the South London Stroke Register

BACKGROUND AND PURPOSE

This article examines stroke recurrence and whether the subtype of the initial stroke influences the risk and subtypes of further strokes. The proportion of recurrences attributable to conventional risk factors is quantified.

METHODS

From January 1995 to August 2000, all first-in-a-lifetime strokes (n=1626) were identified and prospectively followed up in a defined multiethnic inner city population of 234 533. Twelve overlapping referral sources and face-to-face follow-up at 3 months and 1 and 3 years were used to attain complete registration of stroke recurrence. Index and recurrent stroke were classified according to the Oxford Community Stroke Project classification.

RESULTS

In 2744 person-years of follow-up, 153 recurrences were observed. At 5 years, the cumulative risk of first stroke recurrence was 16.6% (95% CI, 13.5 to 20.4), and the combined risk of death or stroke recurrence was 65.3% (95% CI, 61.9 to 68.6). Ethnicity and subtype of index stroke were not associated with stroke recurrence. A change in subtype between index and recurrent stroke occurred in 45.5% (95% CI, 35.8 to 55.2) of cases and was most frequent among index lacunar strokes and primary intracerebral hemorrhages. In multivariable analyses, diabetes mellitus and atrial fibrillation were associated with both stroke recurrence and recurrence-free survival. In the stroke population, 9.1% (95% CI, -2.0 to 20.2) of recurrences were attributable to diabetes and 4.9% (95% CI, -7.3 to 17.2) to atrial fibrillation during the first year after the index stroke.

CONCLUSIONS

The cause of stroke recurrence is multifactorial, and the subtypes of index and recurrent strokes are often not identical. Most recurrences remain unexplained by conventional risk factors.

Long-term prognosis after lacunar infarction

Lacunar infarcts, small deep infarcts that result from occlusion of a penetrating artery, account for about a quarter of all ischaemic strokes. These infarcts have commonly been regarded as benign vascular lesions with a favourable long-term prognosis. However, recent studies have shown that this is only the case early in the disease course. A few years after infarct, there is an increased risk of death, mainly from cardiovascular causes. The risk of recurrent stroke after lacunar infarct is similar to that for most other types of stroke, and patients have an increased risk of developing cognitive decline and dementia. Age, vascular risk factors, high nocturnal blood pressure, and severity of cerebral small-vessel disease at onset have significant prognostic implications for almost all outcomes. More studies on mechanisms, prevention, and treatment are needed to provide specific guidance on the long-term management of patients with lacunar infarcts. Risk-factor modification is likely to play a large part in therapeutic interventions targeted at this stroke subtype.

Lacunar stroke: transoesophageal echocardiographic factors influencing long-term prognosis

OBJECTIVE

Since little is known concerning factors which may influence long-term prognosis of patients presenting with lacunar stroke, we conducted a longitudinal study of this stroke subtype. Variables likely to affect outcome were assessed at baseline, including those from transoesophageal echocardiographic studies.

METHODS

Consecutive patients presenting with first-ever lacunar stroke underwent diagnostic workup that included brain CT or MRI, carotid duplex, and transthoracic and transoesophageal echocardiography. An assessment of patients was planned at entry (baseline), and thereafter every 12 months (clinic visit or telephone call), drop-out, or endpoint. The primary endpoint was nonfatal or fatal stroke. Secondary endpoint was death due to any cause.

RESULTS

Among 60 consecutive lacunar patients with the mean follow-up period of 3.9 years, 12 patients (20%) had stroke recurrence. The mean annual rate for stroke was 5.2%, and for death 2.8%. For multivariate Cox proportional hazards analysis, the following three variables with the values of p < 0.1 after univariate testing were chosen: age (p = 0.095); aortic atheroma (p = 0.066); and any source of embolism from heart (p = 0.007). Any source of embolism from heart was the only factor which significantly enhanced the risk of stroke recurrence (p = 0.015). Using Kaplan-Meier life table analysis, the curves of percent free of recurrent stroke were significantly different (log rank test p = 0.002).

CONCLUSIONS

Until the mechanism of lacunar stroke is better understood, it is reasonable to suggest that its investigation and prevention should be directed at all potential causes of future strokes including cardioembolism.

Mechanisms of second and further strokes

OBJECTIVES

The mechanisms underlying recurrent stroke may be complex and multifactorial, but they have not been studied systematically. The aim was to analyse the different patterns and pathophysiological mechanisms of second and further strokes.

METHODS

Recurrent stroke patterns and mechanisms were studied in 102 patients admitted with second or further strokes to the stroke centre in Lausanne University Hospital.

RESULTS

The patients with an initial cardioembolic stroke experienced recurrent stroke of the same type most often, followed by those with initial non-lacunar non-cardioembolic stroke, brain haemorrhage, and lacunar stroke (77%, 65%, 58%, and 48% respectively). Forty two per cent of the recurrent strokes in patients with an initial brain haemorrhage were ischaemic, whereas patients with ischaemic stroke only occasionally suffered brain haemorrhage (5%). In patients with brain haemorrhage, the lobar location predominated in both the first and all episodes (69% and 78% respectively), suggesting a small, occult arteriovenous malformation or cerebral amyloid angiopathy rather than hypertensive small artery disease. The functional disability of patients after an initial lacunar stroke was significantly better than in patients with other stroke subtypes (p<0.001), but the difference became non-significant after recurrent stroke (p=0.26).

CONCLUSIONS

Most of the recurrent strokes were of the same type as the first episode for both cardioembolic and non-lacunar non-cardioembolic stroke, however, about half of the patients with an initial brain haemorrhage or a lacunar stroke experienced other types of stroke recurrently. The findings suggest that the coexistence of multiple aetiologies may play a major part in determining the mechanism of stroke recurrence. The study is an important step in understanding the patterns of stroke recurrence, which may be critical for better prevention.

Neuroprotective properties of a protein kinase inhibitor against ischaemia-induced neuronal damage in rats and gerbils

1. The neuroprotective properties of fasudil (HA1077), a novel protein kinase inhibitor, were evaluated in two animal models of cerebral ischaemia: transient bilateral carotid artery occlusion in Mongolian gerbils and cerebral microembolization in rats. 2. The cytoprotective effect of fasudil on delayed neuronal death in gerbils was compared with the effects of nimodipine, a calcium channel antagonist and ozagrel, a thromboxane A2 synthetase inhibitor. The average of the neuronal cell density in the ischaemic control group was 17.8 +/- 2.1 cells mm-1, whereas fasudil (30 mg kg-1) significantly diminished the loss of CA1 neurones with the average of the neuronal cell density of 101.0 +/- 22.0 cells mm-1; nimodipine (10 mg kg-1) and ozagrel (30 mg kg-1) did not significantly protect against the ischaemia-induced neuronal loss. 3. In the rat model, the effects of fasudil on the histological and neurological consequences of cerebral microembolization produced via the injection of microspheres were examined. Twenty-four hours after the injection of microspheres into the internal carotid artery, all animals in the control group showed typical symptoms of stroke. Neurological function was significantly improved in the fasudil-treated animals. In the controls, the infarcted area in a cortical slice selected to include the hippocampal area was 0.25 +/- 0.01 cm2 (mean +/- s.e.mean) (43.9 +/- 2.4% of cortical section of the half hemisphere); the difference was significant compared to the mean area of 32.7 +/- 2.8 and 21.5 +/- 4.8% observed in rats treated with fasudil (3, 10 mg kg-1), respectively. Fasudil (10 mg kg-1) significantly suppressed the increased water content in ischaemic brain tissues (saline-treated rats, 82.4 +/- 0.2% vs fasudil-treated rats, 81.0 +/- 0.4%). 4. These results suggest that: (i) various protein kinases are involved in the pathogenesis of ischaemic injury; and (ii) the inhibition of protein kinases may be efficacious in preventing neuronal death, thus improving neurological function in the brain damage associated with ischaemic stroke.

Long-term prognosis of first-ever lacunar strokes. A hospital-based study

BACKGROUND AND PURPOSE

Information concerning the long-term prognosis of lacunar strokes is still limited and has shown different results. The aim of this study was to investigate the long-term prognosis of first-ever lacunar strokes and the possible role of clinical prognostic factors and different pathogenic mechanisms.

METHODS

Between March 1990 and November 1993, a cohort of consecutive patients presenting with first-ever lacunar infarcts was prospectively evaluated after stroke onset at day 0 to 3 and/or day 7, every 3 months up to 1 year, and every 6 months thereafter. All patients were studied according to a protocol that included demographic and clinical data, neurological examination, Toronto Stroke Scale, Barthel Index, Rankin Scale, CT scan, routine laboratory workup, electrocardiogram, carotid duplex scanning, and echocardiogram. More recently, patients have also been evaluated with transcranial Doppler ultrasonography. Recurrent strokes, myocardial infarction, and death were registered through direct observation, chart review, or interviews with the attending physician or family members.

RESULTS

One hundred forty-five patients-94 (65%) with pure hemiparesis, 33 (23%) with sensorimotor stroke, 11 (8%) with ataxic hemiparesis, 5 (3%) with pure sensory stroke, and 2(1%) with dysarthria-clumsy hand syndrome-were followed for a median period of 39 months. During follow-up ther were 17 deaths (3 vascular), 30 recurrent strokes (1 fatal), and 4 myocardial infarctions. Five-year survival rate free of recurrent stroke was 63% (95% confidence interval [CI], 52% to 73%), while 5-year survival rate was 86% (95% CI, 78% to 91%). Cox proportional hazards analysis showed that age (p=.02) was the only significant predictor of survival free of recurrent stroke. Age (P<.001) and the degree of neurological dysfunction and functional disability at 7 days after the index stroke measured by the Toronto Stroke Scale (P=.05) and a Barthel Index score <40 (P=.04) were the only significant predictors of death. The 5-year probability rate of stroke-free recurrence was 72% (95% CI, 60% to 81%). Sixty-three percent of the first recurrent strokes were lacunar infarcts. When clinical, laboratory, and CT data as well as possible etiopathogenic mechanisms of lacunar strokes were considered, Cox proportional hazards analysis could not identify any predictor of stroke recurrence.

CONCLUSIONS

Our study confirms that lacunar infarcts are associated with low stroke recurrence and mortality rates. In our series, the majority of first recurrent strokes were also lacunar infarcts. Age, degree of neurological dysfunction, and functional disability at day 7 after the index stroke were significant predictors of death.

Recurrent stroke after transient ischaemic attack or minor ischaemic stroke: does the distinction between small and large vessel disease remain true to type? Dutch TIA Trial Study Group

The incidence and vascular type of recurrent ischaemic stroke was studied in patients with supratentorial transient ischaemic attacks or non-disabling ischaemic strokes, who were treated with aspirin (30 or 283 mg). Patients were divided into groups with small vessel disease (SVD) (n = 1216) or large vessel disease (LVD) (n = 1221) on the grounds of their clinical features and CT at baseline. Patients with evidence of both SVD and LVD (n = 180) were excluded from further analyses. During follow up (mean 2.6 years) annual stroke rate was 3.6% in both groups. Of the 107 patients with SVD at baseline who had recurrent strokes, 83 proved to have an identifiable infarct: 30 (28%) again had a small vessel infarct, 39 (36%) had a large vessel ischaemic stroke and in 14 (13%) the recurrent ischaemic stroke was in the posterior fossa. Of the 110 patients with LVD at baseline and recurrent stroke, 91 had an identifiable infarct: 67 (61%) again had a large vessel ischaemic stroke, 16 (15%) had a small vessel ischaemic stroke, and eight (7%) had the recurrent ischaemic stroke in the posterior fossa. Thus patients with a transient ischaemic attack or non-disabling ischaemic stroke caused by LVD were more likely to have an ischaemic stroke of the same vessel type during follow up than patients with SVD (relative risk 2.2; 95% confidence interval 1.5-3.4). Possible explanations for this difference are: (1) patients with a small vessel ischaemic stroke at baseline had both SVD and LVD or were misdiagnosed; (2) recurrent small vessel ischaemic stroke may have occurred more often than reported, because they were silent or only minimally disabling; (3) recurring large vessel ischaemic strokes occurring in patients initially diagnosed as having SVD might have been related to potential cardiac sources of emboli that had not been previously recognized; (4) the antiplatelet drug aspirin (30 or 283 mg) prescribed in this patient group may have prevented thrombosis in small vessels better than in large vessels.