Silent brain infarctions in patients with first-ever stroke. A community-based study in Umbria, Italy

Targeting autonomic nervous system as a biomarker of well-ageing in the prevention of stroke

Stroke prediction is a key health issue for preventive medicine. Atrial fibrillation (AF) detection is well established and the importance of obstructive sleep apneas (OSA) has emerged in recent years. Although autonomic nervous system (ANS) appears strongly implicated in stroke occurrence, this factor is more rarely considered. However, the consequences of decreased parasympathetic activity explored in large cohort studies through measurement of ANS activity indicate that an ability to improve its activity level and equilibrium may prevent stroke. In support of these observations, a compensatory neurostimulation has already proved beneficial on endothelium function. The available data on stroke predictions from ANS is based on many long-term stroke cohorts. These data underline the need of repeated ANS evaluation for the general population, in a medical environment, and remotely by emerging telemedicine digital tools. This would help uncovering the reasons behind the ANS imbalance that would need to be medically adjusted to decrease the risk of stroke. This ANS unbalance help to draw attention on clinical or non-clinical evidence, disclosing the vascular risk, as ANS activity integrates the cumulated risk from many factors of which most are modifiable, such as metabolic inadaptation in diabetes and obesity, sleep ventilatory disorders, hypertension, inflammation, and lack of physical activity. Treating these factors may determine ANS recovery through the appropriate management of these conditions. Natural aging also decreases ANS activity. ANS recovery will decrease global circulating inflammation, which will reinforce endothelial function and thus protect the vessels and the associated organs. ANS is the whistle-blower of vascular risk and the actor of vascular health. Such as, ANS should be regularly checked to help draw attention on vascular risk and help follow the improvements in response to our interventions. While today prediction of stroke relies on classical cardiovascular risk factors, adding autonomic biomarkers as HRV parameters may significantly increase the prediction of stroke.

Effect of methylenetetrahydrofolate reductase gene polymorphisms and oxidative stress in silent brain infarction

Ischemic infarctions occur under the influence of genetic and environmental factors. In our study, the role of ischemia-modified albumin and thiol balance, which are new markers in determining oxidative damage together with MTHFR gene polymorphisms and homocysteine levels, in the development of SBI was investigated. White matter lesions in the magnetic resonance imaging (MRI) results of the patients were evaluated according to the Fazekas scale and divided into groups (Grade 0, 1, 2, and 3). Homocysteine, folate, B12, IMA, total thiol, and native thiol were measured by biochemical methods. The polymorphisms in MTHFR genes were investigated by the RT-PCR method. According to our results, a significant difference was found between the groups in age, homocysteine, folate, IMA, total thiol, and native thiol parameters (p < 0.05). When we compared the groups in terms of genotypes of the C677T gene, we found a significant difference in TT genotype between grades 0/3 and 1/3 (p < 0.05). We determined that homocysteine and IMA levels increased and folate levels decreased in CC/TT and CT/TT genotypes in the C677T gene (p < 0.05). Considering our results, the observation of homocysteine and IMA changes at the genotype level of the MTHFR C677T gene and between the groups, and the deterioration of thiol balance between the groups suggested that these markers can be used in the diagnosis of silent brain infarction.

Prevalence of and risk factors for silent ischemic stroke in patients with atrial fibrillation as determined by brain magnetic resonance imaging

Varied silent ischemic stroke (SS) prevalence occurs in patients with atrial fibrillation (AF). Stroke history is worth 2 points in the CHADS2 scoring system. An unknown proportion of patients with AF with a CHADS2 score of 0 or 1 have been undertreated for stroke prevention. We investigated SS risk factors using magnetic resonance imaging and estimated SS impact on clinical outcomes in patients with AF. We analyzed a total of 1,200 patients (400 with AF and 800 with sinus rhythm) who had brain magnetic resonance imaging performed for routine health checkups. Clinical outcomes including symptomatic stroke, dementia, and cognitive disorder were also evaluated in patients with AF (follow-up duration: 66.7 ± 35.9 months; range 10 to 162). SS was observed in 113 patients with AF (28.3%), which was significantly higher than that in 53 subjects (6.6%) with sinus rhythm (p <0.001, odds ratio [OR] 5.549). Independent risk factors for SS in patients with AF were age (OR 1.049), hypertension (OR 2.086), dyslipidemia (OR 2.073), and valvular AF (OR 3.157). Symptomatic stroke incidence during the follow-up was significantly greater in patients with AF with SS than without SS (5.6% vs 2.7% per year, respectively; p = 0.022, hazard ratio 1.787, 95% confidence interval 1.089 to 2.933). Using current scoring systems without correcting for subclinical stroke, clinicians have likely underestimated the stroke risk in low-risk patients with AF; thus many patients with AF might not receive optimal anticoagulation treatment. In conclusion, a screening tool for detecting SS could be considered for stroke risk evaluation in patients with AF, especially those with valvular AF, elderly patients, and patients with dyslipidemia or hypertension.

Silent cerebral infarcts associated with cardiac disease and procedures

The occurrence of clinically silent cerebral infarcts (SCIs) in individuals affected by cardiac disease and after invasive cardiac procedures is frequently reported. Indeed, atrial fibrillation, left ventricular thrombus formation, cardiomyopathy, and patent foramen ovale have all been associated with SCIs. Furthermore, postprocedural SCIs have been observed after left cardiac catheterization, transcatheter aortic valve implantation, CABG surgery, pulmonary vein isolation, and closure of patent foramen ovale. Such SCIs are often described as precursors to symptomatic stroke and are associated with cognitive decline, dementia, and depression. Increased recognition of SCIs might advance our understanding of their relationship with heart disease and invasive cardiac procedures, facilitate further improvement of therapies or techniques aimed at preventing their occurrence and, therefore, decrease the risk of adverse neurological outcomes. In this Review, we provide an overview of the occurrence and clinical significance of, and the available diagnostic modalities for, SCIs related to cardiac disease and associated invasive cardiac procedures.

Silent brain infarction in the presence of systemic vascular disease

Objective

To determine the prevalence of asymptomatic brain ischaemic in the presence of vascular disease in other arterial territories.

Design

Studies up to January 2011 were identified through comprehensive search strategies. Arcsine transformation for meta-analysis was used to calculate the standardized mean difference (SMD) and 95% confidence intervals (CI).

Setting

A systematic review and meta-analysis were performed.

Participants

For each study, the proportion of patients positive for SBI in the presence of other systemic vascular disease was extracted and analyzed.

Main outcome measures

Using a random-effects model, a pooled effect estimate interpreted as a percentage prevalence of disease was calculated.

Results

SBI in the presence of acute ischaemic stroke was found in 23% (SMD 0.99; P < 0.001; 95% CI 0.88–1.10); a 35% prevalence was found in patients with coronary artery disease (SMD 1.26; P < 0.001; 95% CI 0.95–1.58); and a 14% prevalence in patients with peripheral artery disease (SMD 0.48; P < 0.002; 95% CI 0.42–0.54), although the data-set in the latter is smaller.

Conclusions

Patients with systemic vascular disease are at an increased risk of silent brain infarction.

Lacune-associated cerebral hypoperfusion correlates with cognitive testing

The hypothesis was tested among 83 patients with multiple lacunar infarctions that cerebral hypoperfusion will correlate with cognitive impairments. Patients were subdivided according to Cognitive Capacity Screening Examination (CCSE) scores into a cognitively impaired group (Group D, n = 40; mean age, 68.2 years) with CCSE scores between 6 and 25 (mean, 19.9) and a cognitively intact group (Group I, n = 43; mean age, 66.0) with normal scores (mean, 29.4). Gray and white matter tissue densities were measured by plain computed tomography (CT), and their compartmental perfusions were estimated during stable xenon inhalation. Eighty infarcts in basal ganglia and white matter were detected in Group D and 62 in Group I. Cognitive impairments correlated with (a) multiplicity and bilaterality of lacunes; (b) hypertension, diabetes mellitus, and multiplicity of risk factors for stroke; (c) hypoperfusion of white and gray matter, but particularly of frontal white matter; (d) leuko-araiosis; (e) aging; and (f) lower education. The conclusion was that hypertension and diabetes mellitus are potent risk factors for cerebral small vessel disease or arteriolosclerosis ultimately resulting in lacunar infarcts, leuko-araiosis, white matter hypoperfusion, and impaired cognitive test performance.

Association between cholesterols, homocysteine and silent brain infarcts

BACKGROUND

The aim of this study was to assess the relationship between total plasma homocysteine, cholesterol levels, vitamin B(12), folate, thyroid hormones, urea, ferritin, uric acid, C-reactive protein, cardiovascular risk factors and silent brain infarct (SBI) in patients without any neurological disorder. Whether the factors of interest were associated with SBI is investigated.

METHODS

One hundred and forty-two subjects with a mean age of 52.1 +/- 13.1 years (21-87 years) without any history of stroke, transient ischaemic attack and neurological abnormality were enrolled in this cross-sectional study. The subjects underwent brain magnetic resonance imaging and blood chemistry determinations. Student's t-test was used to compare differences in means of laboratory results between the groups with and without SBI. The chi(2)-test was used for categorized variables. Multiple logistic regression analysis was used to determine the independent predictors of SBI.

RESULTS

The group comprised 56 men and 86 women. SBI were found in 40 patients (28%). The low-density lipoprotein levels were significantly higher in the infarct group (P = 0.019), homocysteine concentrations were significantly higher in the men-infarct group (P = 0,029) and total cholesterol levels were significantly higher in the women-infarct group than the women non-infarct group (P = 0.006).

CONCLUSION

Serum low-density lipoprotein, total cholesterol and homocysteine levels were associated with SBI.

Prevalence of atrial fibrillation and stroke in paced patients without prior atrial fibrillation: a prospective study

BACKGROUND

Several reports suggest that the incidence of stroke and atrial fibrillation is reduced in patients receiving physiologic pacemakers, compared with patients receiving a ventricular pacemaker.

HYPOTHESIS

The study was undertaken to address the impact of different pacing modalities on the incidence of stroke and atrial fibrillation.

METHODS

We prospectively analyzed 210 consecutive patients. Those with previous episodes of cerebral ischemia and/or atrial fibrillation were excluded from the study. The study population included 100 patients paced for total atrioventricular (AV) block or second-degree AV block (type II Mobitz) and 110 patients paced for sick sinus syndrome (SSS). The pacing mode was randomized. All patients underwent a brain computed tomography (CT) scan at the date of enrollment and after 1 and 2 years. Patients were followed for 2 years, and the incidence of atrial fibrillation and stroke was evaluated.

RESULTS

The incidence of atrial fibrillation was 10% at 1 year and 11% at 2 years. Comparing the different pacing modalities, we reported an increase in the incidence of atrial fibrillation in patients receiving ventricular pacing (p < 0.05). On the other hand, no difference was found between patients paced for AV block and those paced for SSS. At the end of follow-up, we reported 29 cases of cerebral ischemia: 9 patients had AV block while 20 had SSS (p < 0.05). Comparing the different pacing modalities, there was an increase in the incidence of stroke in patients receiving ventricular pacing (p < 0.05).

CONCLUSION

There was an increase in the incidence of stroke and atrial fibrillation in patients with ventricular pacing.

Silent cerebral infarction in chronic heart failure: ischemic and nonischemic dilated cardiomyopathy

Objectives

Patients with dilated cardiomyopathy (DCM) may have a high incidence of clinically asymptomatic silent cerebral infarction (SCI). Prevalence of SCI and its risk factors may differ between ischemic and nonischemic DCM. The purpose of this study was to evaluate prevalence and related parameters of silent cerebral infarction in patients with ischemic and nonischemic DCM.

Methods

Patients with ischemic and nonischemic DCM (53 male, 19 female, aged 62 ± 12 years) were included in the study. Etiology of DCM was ischemic in 46 and nonischemic in 26 patients. Fifty-six age- and gender-matched healthy volunteers served as a control group for comparison of SCI prevalence.

Results

Prevalence of SCI was 39%, 27%, and 3.6% in ischemic, nonischemic DCM, and control group, respectively (ischemic DCM vs control group, p < 0.001, nonischemic DCM vs control group, p = 002). In patients with nonischemic DCM, the mean age of the subjects with SCI was significantly higher than that of subjects without lesions (67 ± 5 years vs 53 ± 13, p < 0.001), whereas in ischemic DCM NHYA Functional Class was statistically higher in patients with SCI than without SCI (p = 0.03). In both groups, patients with SCI had lower systolic functions than patients with normal MRI findings. In multivariable logistic regression analysis, restrictive type of diastolic filling pattern was found as an independent factor for SCI occurrence on the whole patient population (OR: 16.5, 95% CI: 4.4–61.8, p < 0.001).

Conclusion

SCI is common in patients with both ischemic and nonischemic DCM. In univariate analysis, both groups have similar systolic and diastolic characteristics in the occurrence of SCI. Logistic regression analysis revealed that restrictive diastolic filling pattern is an independent risk factor in the occurrence of SCI for the whole patient population.

Silent cerebral infarction in patients with dilated cardiomyopathy: Echocardiographic correlates

BACKGROUND

Patients with dilated cardiomyopathy (DCM) have an increased risk of thromboembolic events. Incidence of silent cerebral infarction (SCI) has not been investigated in these patients. The aim of this study was to investigate the incidence of SCI in patients with DCM and to determine its associations with echocardiographic parameters.

METHODS AND RESULTS

Seventy-two patients (mean age 62+/-12 years) with DCM underwent cranial magnetic resonance imaging in addition to transthoracic and transesophageal echocardiographic examination. A total of 56 age-matched healthy volunteers served as a control group for comparison SCI prevalence. Prevalence of SCI was significantly higher in patients with DCM (35% vs. 3.6%; p<0.001). In DCM group, patients with SCI had significantly impaired left ventricular systolic function, higher frequency of restrictive diastolic filling, moderate to severe left atrial spontaneous echo contrast (SEC), aortic SEC, and complex atherosclerosis or calcified plaques in the aorta. In logistic regression analysis, type of diastolic filling emerged as the only independent risk factor for SCI (p<0.001). When the type of diastolic filling was removed from the analysis, ejection fraction, marked left atrial SEC, complex-calcified aortic atheroma and age appeared as the other independent risk factors (p = 0.003, p = 0.009, p = 0.013 and p = 0.018, respectively).

CONCLUSION

SCI is a frequent finding in DCM patients. Impaired systolic function, restrictive filling pattern, presence of moderate to severe left atrial SEC, and complex atherosclerosis in the aorta are the factors contributing to the development of SCI.

Functional and cognitive consequences of silent stroke discovered using brain magnetic resonance imaging in an elderly population

OBJECTIVES

To evaluate the prevalence of silent stroke and its associated consequences on physical, cognitive, and emotional functioning in an elderly population.

DESIGN

Population-based cross-sectional survey.

SETTING

The Memory and Morbidity in Augsburg Elderly project in the Augsburg region of southern Germany.

PARTICIPANTS

Two hundred sixty-seven community-dwelling persons aged 65 to 83.

MEASUREMENTS

The presence of silent stroke was determined using magnetic resonance imaging brain scan and a single question asking for physician-diagnosed stroke in each participant. The health effect of silent stroke was assessed using rating scales for self-perceived health status (36-item short-form health survey), activities of daily living (ADLs) and instrumental ADLs, cognitive function, and depression (Center for Epidemiologic Studies Depression scale).

RESULTS

Just fewer than 13% (12.7%) of participants were affected by silent stroke. Silent stroke was associated with a history of hypertension, heart surgery, and elevated C-reactive protein. Individuals with silent stroke showed impairments on the Mini-Mental State Examination test and in the cognitive domains of memory, procedural speed, and motor performance.

CONCLUSION

The presence of silent stroke has a considerable effect on cognitive performance in those affected. Determining the presence of silent stroke using brain imaging may contribute to identifying individuals at risk for developing gradual neurological deficits.

Lacunar stroke in patients with intermittent claudication

OBJECTIVES

To compare the characteristics of lacunar stroke (LS) in patients with and without intermittent claudication.

MATERIAL AND METHODS

Data of 484 consecutive patients with LS were collected from a prospective hospital-based stroke registry in which 2500 patients are included.

RESULTS

Of the 142 patients with ischemic stroke and intermittent claudication, 39 (27.5%) had LS (8% of all lacunes). In the multivariate analysis, small centrum ovale topography (odds ratio 7.35), carotid stenosis >50% (odds ratio 3.17), and absence of limitation at discharge (odds ratio 2.01) were independent variables significantly associated with LS in patients with intermittent claudication.

CONCLUSION

Only 8% of patients with LS had intermittent claudication. The short-term prognosis is good with a spontaneous early neurological recovery at discharge in 51.3% of patients. LS patients with intermittent claudication showed a striking similarity in risk factors and clinical syndromes in comparison with the LS patients without intermittent claudication.

Aspirin attenuates the incidence of silent brain lesions in patients with nonvalvular atrial fibrillation

BACKGROUND

Abnormal findings, including silent cerebral infarction, are frequently observed by magnetic resonance imaging (MRI) in patients with nonvalvular atrial fibrillation (NVAF); however, the prevalence and prevention strategy for these lesions have not been extensively studied. In the present study the preventive effects of aspirin on silent ischemic lesions was investigated.

METHODS AND RESULTS

Silent lesions were counted using cranial MRI performed in 78 neurologically normal adults with sinus rhythm and in 212 patients with NVAF without a history of stroke. MRIs were repeated twice in the NVAF patients at 12-month intervals. During the first year, patients received neither antiplatelet agent nor anticoagulant; in the second year, aspirin (330 mg daily) was administered. The prevalence of lesions in the initial MRI was higher in NVAF patients (86.4%) than in sinus rhythm subjects (53.8%; p<0.001). After 12 months without aspirin, new lesions were seen in 20.6% of NVAF patients. The yearly occurrence of new lesions was decreased to 9.6% during the year of treatment with aspirin (p=0.014).

CONCLUSIONS

In patients with NVAF, abnormal lesions are frequently observed by MRI and aspirin treatment may be effective in preventing further small silent lesions.

Obstructive sleep apnoea and stroke

Many patients with stroke have concomitant sleep apnoea, which can affect recovery potential. Although stroke can lead to the development of sleep-disordered breathing, the current evidence suggests that sleep-disordered breathing may function as a risk factor for stroke. In this review, we focus on the association between obstructive sleep apnoea and stroke reviewing both the epidemiological data with respect to causation and the biological data, which explores pathogenesis. There is convincing evidence to believe that sleep apnoea is a modifiable risk factor for stroke; however, prospective studies are needed to establish the cause-and-effect relationship.

Confused and disturbed behavior in the elderly following silent frontal lobe infarction

It is unclear whether silent frontal lobe infarction is truly asymptomatic; frontal behavioral syndromes following strokes have rarely been reported. We studied 12 elderly patients with silent frontal lobe infarction who were exhibiting confused and disturbed behavior. Ten were male and two female; their ages ranged from 68 to 79 (mean 78). Three groups of symptom clusters emerged: changes in mood and emotional behavior, cognitive deterioration with minor psychiatric symptoms, and a confusional state. When related to the CT scan location, three regions were identified: predominantly orbitofrontal, deep white matter and caudate, and border-zones, respectively. These findings were related to what is known about the neuroanatomic location of the lesions and the role of the frontal subcortical circuitry in relation to behavior. The different manifestations could be explained by damage to the frontal lobe or interruption of the complex frontal subcortical circuits.

Sleep-disordered breathing and stroke

Sleep-related breathing disorders are strongly associated with increased risk of stroke independent of known risk factors. The direction of causation favors sleep-disordered breathing leading to stroke rather than the other way around, although definitive proof of this awaits the results of prospective cohort studies. If causal, even a moderately elevated risk of stroke coupled with the high prevalence of sleep-disordered breathing could have significant public health implications. The relationship between sleep-disordered breathing and stroke risk factors is complex, and likely part of the risk for cerebrovascular events is because of higher cardiovascular risk factors in patients with increased RDI. The mechanisms underlying this increased risk of stroke are multi-factorial and include reduction in cerebral blood flow, altered cerebral autoregulation, impaired endothelial function, accelerated atherogenesis, thrombosis, and paradoxic embolism. Because of the effects of sleep-disordered breathing on vascular tone, hypertension is believed to be a major mechanism by which sleep-disordered breathing might influence risk of stroke. Because sleep-related breathing disorders are treatable patients with stroke/TIA should undergo investigation, with a thorough sleep history interview, physical examination, and polysomnography. Treatment of sleep apnea has been shown to improve quality of life, lower blood pressure, improve sleep quality, improve neurocognitive functioning, and decrease symptoms of excessive daytime sleepiness [98]. Further treatment trials are needed to determine whether treatment improves outcome after stroke and whether treatment may serve as secondary prophylaxis and modify the risk of recurrent stroke or death.

Hypersexuality in nursing care facilities—a descriptive study

The continuance of sexual expression in the elderly as age advances is well recognized. Sexual disinhibition, however, in a restricted environment such as in nursing care facilities has received scant attention. We wish to describe eight patients residing in nursing care facilities who were seen because of their problematic sexually related behaviors. These behaviors include cuddling, touching of the genitals, sexual remarks propositioning, grabbing and groping, use of obscene language and masturbating without shame. In all instances concern emanated from members of the nursing staff. Other associated behaviors included aggression, agitation, and irritability amongst others. The computed tomography (CT) scan of the brain showed infarction in the frontal lobe (4), parietal lobe (1), and the caudate (1). One had severe Parkinson's Disease and one had severe dementia of the Alzheimer's disease. All ten patients had an organic basis for their symptoms. Sexually inappropriate behaviors remain highly controversial and labeling them as 'diseased' or an 'illness' may have enormous individual, cultural and medico-legal implications. The clinico-anatomical correlation are discussed.

Brain CT-scan in acute stroke patients: silent infarcts and relation to outcome

Silent infarcts (SIs) are common findings in stroke patients, but their clinical significance remains controversial. Aim of this study was to evaluate the prevalence of SI in consecutive stroke patients, characteristics, associated factors, and influence on in-hospital mortality. The population consisted of 191 patients, consecutively admitted for an acute stroke. Of 191 patients, 74 had SI on CT-scan. Silent infarcts were often multiple, right sided, lacunar. We found SI more frequently in older patients, smokers, with an ischemic stroke having small vessel disease as presumed cause. In our study SI were associated with ageing, smoke habit and lacunar stroke. Silent infarcts size influenced the rate of in-hospital mortality.

Quantitative MRI findings and cognitive impairment among community dwelling elderly subjects

OBJECTIVES

To study the factors which influence cognitive impairment among elderly subjects living in a local community, based on both MRI and clinical findings, to further elucidate the causes of dementia, and also to help develop strategies for its prevention.

METHODS

Cranial MRI and other medical examinations were performed on non-demented elderly subjects who resided in one rural community. A total of 254 subjects aged from 60 to 91 years of age, with a mean age of 73.9 (SD 6.8) were examined. The mini mental state examination (MMSE) was used to identify cognitive impairment. White matter lesions and cerebral atrophy on MR images were measured quantitatively. A multivariate analysis was also performed with the existence of cognitive impairment as the dependent variable, and the MRI findings and clinical observations were used as the independent variables.

RESULTS

Cognitive impairment was present in 46 subjects (18.1%). They were older, had a lower educational level, and more frequent hypertension compared with those without cognitive impairment. The packed cell volume was lower in the impaired group. In addition, their MRI findings showed significantly larger quantities of white matter lesions and cerebral atrophy, as well as more infarcts. A logistic regression analysis demonstrated a significant relation among such factors as white matter lesions (odds ratio (OR) 1.575, 95% confidence interval (95% CI) 1.123-2.208), cerebral atrophy (OR 0.761, 95%CI 0.587-0.987), and lower education (OR 0.682, 95%CI 0.544-0.855) for subjects with a cognitive impairment.

CONCLUSIONS

White matter lesions and cerebral atrophy are factors which induce a cognitive impairment in community dwelling elderly subjects without dementia. It is important to carefully watch for any abnormalities in these factors, and to perform cohort studies to check for the above risk factors, to both prevent and make an early diagnosis of dementia.

Silent brain infarction in patients with rheumatic mitral stenosis

Silent brain infarction (SBI) is defined as asymptomatic infarction areas detected in computerized tomography (CT) scans in patients without a history of stroke. The incidence of SBI is increased in CT or magnetic resonance imaging in patients with carotid stenosis and with atrial fibrillation (AF), but its relation with rheumatic mitral stenosis (MS), another major source of emboli, is uncertain. The aim of this study was to investigate the incidence of SBI in patients with MS. Fifty-three patients with MS (44 females and 9 males; range 25-52 years; mean age 38 +/- 7 years) diagnosed by transthoracic echocardiography (TTE) were enrolled in the study. Mitral valve calcification, left atrium (LA) dimension, and the presence of associating mitral regurgitation on TTE were recorded. Electrocardiographic evaluation was done for rhythm analysis and neurologic examination was performed prior to cerebral CT. Carotid artery Doppler examination was carried out in patients with SBI to exclude carotid artery lesions. Patients with a history of hypertension, diabetes mellitus, anticoagulant drug usage, presence of thrombus in LA, left ventricular segmental or systolic dysfunction, or other valve diseases were excluded from the study. The incidence of SBI was found to be 24.5% in patients with MS (47% cortical, 53% lacunar). SBI was observed to be significantly high in patients with LA dimension > 4 cm or in patients with AF (p < 0.05). The SBI incidence was markedly higher if AF was found with enlarged LA when compared with patients having sinus rhythm and small LA (p < 0.01). When moderate to severe mitral regurgitation was associated with MS, the SBI incidence was found to be lower (p < 0.05). Although SBI was higher in patients with MVA < 1.5 cm2, it was not statistically significant (p > 0.05). No significant correlation was found between calcific and noncalcific valves for SBI (p > 0.05). Our data suggest that SBI may be expected in about 1/4 of patients with MS. The presence of LA enlargement and AF increase the incidence of SBI in patients with MS, whereas the presence of moderate to severe mitral regurgitation decreases the incidence of SBI.

Carotid disease in acute stroke: A review

This article reviews the literature about carotid disease in acute stroke. Several conclusions are drawn. First, carotid disease is an important cause of ipsilateral cortical strokes, with significant ipsilateral disease found in about one fourth of patients. Second, the role of carotid disease in lacunar stroke is less certain but probably causes a small number of lacunar infarcts. Third, the majority of infarcts that occur with severe carotid stenosis or acute carotid occlusion are caused by cerebral emboli, whereas most infarcts with preexisting occlusion are probably caused by hemodynamic factors. Fourth, the optimal timing of carotid surgery in acute stroke is uncertain. Clinical trials of endarterectomy in acute stroke are now required.

Cerebral tomographic findings in patients undergoing carotid endarterectomy for asymptomatic carotid stenosis: short-term and long-term implications

PURPOSE

Preoperative cerebral imaging has been considered not to be cost-effective in carotid endarterectomy (CEA) for asymptomatic carotid stenosis. Yet, silent brain infarction (SBI) has been associated with the embolization potential of a severe carotid stenosis. Thus the presence of SBI may represent an additional indication for CEA in asymptomatic patients. We examined the predictive value of preoperatively detected silent cerebral lesions on early and late outcomes in patients undergoing CEA for asymptomatic carotid stenosis.

METHODS

Preoperative cerebral tomographic (CT) scans performed on 301 asymptomatic patients undergoing 346 CEAs from 1986 to 1995 were reviewed by a single neuroradiologist blinded to patients' records. Mean follow-up was 67. 3 months (range, 24-130 months). The degree of internal carotid lumen reduction was measured bilaterally in all patients (602 carotid arteries); carotid stenosis of 60% or more was found in 399 carotid arteries.

RESULTS

Of the 103 (34%) CT scans positive for cerebral lesions, 58% were lacunar. No significant association was observed between the side of the cerebral lesion on CT scan and the severity of the corresponding carotid stenosis; 38 silent lesions were detected in the 203 hemispheres ipsilateral to carotid stenoses that were less than 60% versus 95 SBIs in the 399 hemispheres ipsilateral to carotid stenoses that were 60% or more (19% vs 24%; P =.2). There were no significant differences in the perioperative stroke/death rate in patients with or without cerebral CT lesions (2% vs 1%; odds ratio, 1.94; P =.6). Mortality rate during follow-up was 22% in patients with preoperative SBI and 15% in patients without SBI (P =.1). However, actuarial survival at 10 years was shorter (P =.02) in patients with SBI. Late stroke occurred in 11% of patients with preoperative SBI and in 3% of patients without preoperative SBI (P =.006). Cox regression analysis showed that both preoperative lacunar and nonlacunar infarctions were independent predictors of late stroke (hazard ratio, 3.6; P =.04; and hazard ratio, 7.1; P =.001; respectively).

CONCLUSION

In our experience, preoperative SBI did not occur more frequently in the hemisphere ipsilateral to asymptomatic severe carotid stenosis. Although our study lacks a medically treated control group, our data show that SBI is predictive of poor neurologic outcome in asymptomatic patients undergoing CEA. We conclude that CT before CEA, selectively applied, provides information on long-term neurologic prognosis and that a less aggressive attitude towards CEA in asymptomatic patients with SBI may be justified.

The changes of lacunar state during a 5-year period in NIDDM

With the increment of the aged, primary and secondary prevention of cerebrovascular disease in the Japanese diabetics are crucial problems. Early detection of asymptomatic infarction, not rare in diabetics, is important in the view of cost benefits. Little is known about the development and progression of asymptomatic infarction. We investigated the number of lacuna during a period of 5 years in 51 non-insulin-dependent diabetes mellitus (NIDDM). At the initiation of this study, 22 patients were free from lacuna and another 29 patients had asymptomatic multiple lacunae. In the former patients, no risk factors were different between the 13 patients with still no lacuna and the nine patients with lacuna-developed after 5 years. In the latter patients, the 17 patients with worsening lacunar state had significantly higher systolic blood pressure, and a higher prevalence of macroalbuminuria than the 12 patients with no increment of lacuna. Multiple logistic regression analysis showed that macroalbuminuria after 5 years was the only contributing factor to the increased lacuna. Therefore, in the NIDDM, macroalbuminuria induced an increase of lacuna in magnetic resonance imaging, although numbers of cases were relatively small. Prevention of the development of macroalbuminuria are essential to avoid the progression of asymptomatic lacuna.

Cerebral blood flow and metabolism in patients with silent brain infarction: occult misery perfusion in the cerebral cortex

OBJECTIVES

Silent brain infarction (SBI) is of growing interest as a possible risk factor for symptomatic stroke. Although morphological characteristics of SBI have been well defined, their characteristic patterns of cerebral blood flow (CBF) and metabolism are in dispute. The purpose of this study was to elucidate CBF and metabolism in patients with SBI in relation to symptomatic stroke.

METHODS

The patients underwent PET and were separated into three groups; control group (C group), with no lesions on CT (n=9, mean age 57), SBI group, with no neurological signs or history of stroke, but with ischaemic lesions on CT (n=9, mean age 63), and brain infarction group (BI group), with neurological deficits and compatible CT lesions in the area supplied by perforating arteries (n=19, mean age 56). Regional CBF, oxygen extraction fraction (OEF), cerebral metabolic rate for oxygen (CMRO2), and cerebral blood volume (CBV) were measured by PET.

RESULTS

Mean values for CBF to the cerebral cortex and deep grey matter were lower in the SBI group (31.6 (SD 5.8) and 34.3 (SD 6.9) ml/100 g/min, respectively) and in the BI group (30.8 (SD 5.2), 33.9 (SD 5.9), respectively) than in the C group (36.0 (SD 6.6) and 43.5 (SD 9.5), respectively). Although mean CMRO2 of deep grey matter (2.36 (SD 0.52) ml/100 g/min) was significantly decreased in the SBI group compared with the C group (2.76 (SD 0.480), p<0.01), CMRO2 of the cortical area was as well preserved in the SBI patients (2.36 (SD 0.39)) as in the controls (2.48 (SD 0.32)) with a compensatory increase of mean OEF (0.45 (SD 0.06) and 0.41 (SD 0.05), respectively).

CONCLUSIONS

Patients with SBI showed decreased CBF and CMRO2 in deep grey matter. On the other hand, decreased CBF with milder increased OEF, resulting in preserved CMRO2 in the cerebral cortex indicates the presence of occult misery perfusion, suggesting that patients with SBI have reduced cerebral perfusional reserves.

Silent lacunar infarcts in elderly patients with chronic non valvular atrial fibrillation

It is still debated whether non valvular atrial fibrillation (NVAF) may be responsible for "silent" lacunar lesions. The aims of our study were to compare the prevalence of subcortical lacunar infarctions in highly selected elderly subjects with or without NVAF, and to investigate the positive relationship of such lesions to the impairment in cognitive and physical functions. Thirty-eight patients with NVAF (mean age 80.6 years) were compared with 40 patients in sinus rhythm (mean age 80.4 years). Exclusion criteria were previous stroke or transient ischemic attacks, significant lesions of extracranial arteries, and any previous disease leading to cognitive impairment or potentially interfering with cognitive functions. A cranial computed tomogram was performed in every case, and the number of lacunae was recorded. Cognitive status and mood were assessed by means of Mini Mental Status Examination and the Geriatric Depression Scale, respectively. The number of impaired basic and instrumental activities of daily living (BADL e IADL) was also recorded. A significantly higher percentage of patients with lacunar lesions was detected in the NVAF group. The MMS score was lower in these patients, but did not reach significant levels. In univariate analysis, the presence of lacunae was found to be significantly associated with age, systolic blood pressure and atrial fibrillation, but, in a multiple logistic regression model, only age and atrial fibrillation retained a significant association. Similarly, in univariate analysis, a low MMS score was found to be related to age, systolic blood pressure, leukoaraiosis and both the presence and the number of lacunar lesions. In multivariate analysis, only age and the number of lacunae were significantly associated with a low MMS. It is concluded that in elderly patients NVAF is associated with subcortical ischemic lesions which may contribute to the impairment of cognitive function.

The Copenhagen Stroke Study experience

The Copenhagen Stroke (COST) Study was a prospective, consecutive, community-based study of 1,197 patients with acute stroke who underwent acute stroke care and rehabilitation in a stroke unit setting. This article reviews the results of this study with respect to (1) the effect of organized stroke care and rehabilitation, (2) neurological outcome and functional outcome of stroke in relation to initial stroke severity and functional disability, (3) recovery of upper-extremity function and walking, (4) time course of neurological and functional recovery relative to initial stroke severity, (5) mechanisms of stroke recovery, and (6) the effect on stroke recovery of various demographic, medical, and pathophysiological factors, such as stroke in progression, spontaneous reperfusion age, diabetes, blood glucose on admission, stroke type (hemorrhage/infarction), silent infarction, and leuco-araiosis.

Computerised tomography findings as a risk factor in carotid endarterectomy: early and late results

OBJECTIVES

To evaluate whether preoperative CT evidence of brain infarction is associated with an increased risk of early and late stroke and death in patients undergoing CEA.

DESIGN

Retrospective clinical study.

MATERIALS AND METHODS

We evaluated 844 CT scanning records from 893 patients undergoing CEA from 1986-1994: 43% (367) CT positive for cerebral infarction and 57% (477) negative. Univariate and multivariate analysis was performed for risk factors and preoperative symptoms in patients with positive and negative CT scans, and Kaplan Meier survival curves for late events.

RESULTS

A positive CT was significantly more frequent in males vs. females (p < 0.0001; O.R. 2.52; C.I. 1.73-3.73), diabetics vs. non-diabetics (p = 0.03; O.R. 1.52; C.I. 1.03-2.26), symptomatics vs. asymptomatics (p < 0.001; O.R. 2; C.I. 1.93-3.53) and contralateral occlusion vs. patency (p < 0.001; O.R. 2; C.I. 1.30-3.10). The perioperative disabling stroke/ death rate was higher in patients with a positive CT (p = 0.002; O.R. 6.27; C.I. 1.73-34.20); in asymptomatic patients this difference was striking (5 patients vs. O, p = 0.0002). Multiple logistic regression analysis for risk factors, CT findings, symptoms preceding surgery, and congruity of brain infarction confirmed a significantly higher incidence of perioperative stroke/death rate (p = 0.003; O.R. 6.37; C.I. 5.12-7.63) and early and late stroke (p = 0.02; O.R. 1.95; C.I. 1.38-2.53) and death (p = 0.0005; O.R. 2.38; C.I. 1.89-2.88) in patients with brain lesions. After 7 years, the survival rate (p = 0.0009) and stroke-free interval (p = 0.003) were lower in patients with a positive CT. After 5 years, in asymptomatic patients the survival rate (p = 0.003) and stroke-free interval (p = 0.01) were lower in the positive CT group.

CONCLUSIONS

A positive CT finding, regardless of congruity of the lesion, should be regarded as an indicator of an increased risk of stroke and death in patients scheduled for carotid surgery, especially in those with asymptomatic stenosis.

Asymptomatic multiple lacunae in diabetics and non-diabetics detected by brain magnetic resonance imaging

We investigated the relationship between asymptomatic multiple lacunae (ASML) and related risk factors by using brain MRI in 209 patients including 152 NIDDM patients. Patients with ASML (97 cases) were significantly older (68 +/- 9 vs. 63 +/- 10) and hypertension was more frequent (57/97 vs. 33/112) than in patients without ASML. In addition, by multivariate analysis, ASML showed significant association with aging and hypertension, but not with NIDDM. In the NIDDM patients, diabetics with ASML were significantly older, and showed a higher association with hypertension and triopathy than those without ASML, although the results were the same for the middle-aged (< 65 years old) diabetics. From multivariate analysis, the lesions in the penetrating branch area were highly associated with hypertension (F = 8.46) and nephropathy (F = 4.75), while those in the subcortex and white matter were associated with aging (F = 6.02) and retinopathy (F = 5.15). In the middle-aged diabetics, the former was associated with hypertension (F = 10.72) and retinopathy (F = 13.32), whereas the latter was associated with retinopathy (F = 20.76). In the elderly diabetics, no significant association was found in either lesions. These results suggest that control of hypertension and prevention of microangiopathy by keeping good control of blood glucose, is essential to prevent asymptomatic lacunae in NIDDM patients.

Stroke and atrial fibrillation: risks, prevention and therapy in the elderly

Atrial fibrillation (AF) represents a high risk of systemic embolism, particularly of stroke (S). This is true not only when AF is associated with an organic cardiopathy, but also in the so-called nonvalvular AF (NVAF). Not all cases of AF are of the same S-risk; such risk is higher for rheumatic AF and lower for NVAF. Therefore, a risk stratification is important in order to decide long-term antithrombotic prophylaxis. Five major trials have recently examined the thromboembolic prophylaxis in this group of patients. These randomised prospective open studies showed a significant reduction of S and systematic embolism in patients receiving low dose of warfarin (W), even in the elderly, as compared to placebo, and the incidence of hemorrhagic complications was also very low. Significant benefits of aspirin (ASA) were observed only in one trial in patients, except those older than 75 years. In a double blind, randomised trial indobufene was found effective resulting in 67% reduction of S and systematic embolism in patients with various cardiac diseases in AF or sinus rhythm. Consequently, a reasonable policy would be to treat patients with NVAF (also old ones) with anticoagulants unless contraindications or lone atrial fibrillations are present; in the latter cases ASA and indobufene should be considered. In the secondary prevention of ischemic S, W has given good results, whereas ASA and indobufene seem to be promising.