Risk of stroke with mitral valve prolapse in population-based cohort study

TOAST stroke subtype classification in clinical practice: implications for the Get With The Guidelines-Stroke nationwide registry

Introduction

The TOAST (Trial of ORG 10172 in Acute Stroke Treatment) is the most commonly used ischemic stroke subtype classification system worldwide and a required field in the US National Get With The Guidelines-Stroke (GWTG-Stroke) registry. However, stroke diagnostics have advanced substantially since the TOAST classification was designed 30 years ago, potentially making it difficult to apply reliably.

Methods

In this prospective diagnostic accuracy study, we analyzed consecutive ischemic stroke patients admitted to a Comprehensive Stroke Center between July-October 2021. Clinical practice TOAST classification diagnoses rendered by the stroke team in the electronic medical record (EMR) at discharge were retrieved from GWTG-Stroke registry and compared to a reference ("gold") standard diagnosis derived from agreement between two expert raters after review of the EMR and patient imaging.

Results

Among 49 patients; age was 72.3 years (±12.1), 53% female, and presenting NIHSS median 3 (IQR 1-11). Work-up included: brain imaging in 100%; cardiac rhythm assessment in 100%; cervical/cerebral vessel imaging in 98%; TTE ± TEE in 92%; and TCD emboli evaluation in 51%. Reference standard diagnoses were: LAA-6%, SVD-14%, CE-39%, OTH-10%, UND-M (more than one cause)-20%, and UND-C (cryptogenic)-10%. GWTG-Stroke TOAST diagnoses agreed with reference standard diagnoses in 30/49 (61%). Among the 6 subtype diagnoses, specificity was generally high (84.8%-97.7%), but sensitivity suboptimal for LAA (33%), OTH (60%), UND-M (10%), and UND-C (20%). Positive predictive value was suboptimal for 5 of the 6 subtypes: LAA (13%), SVD (58%), OTH (75%), UND-M (50%), and UND-C (50%).

Discussion

Clinical practice TOAST classification subtype diagnoses entered into the GWTG-Stroke registry were accurate in only 61% of patients, a performance rate that, if similarly present at other centers, would hamper the ability of the national registry to provide dependable insights into subtype-related care. Development of an updated ischemic stroke subtype classification system, with algorithmic logic embedded in electronic medical records, is desirable.

Multimodal Cardiac Imaging in the Assessment of Patients Who Have Suffered a Cardioembolic Stroke: A Review

Cardioembolic strokes account for 20-25% of all ischaemic strokes, with their incidence increasing with age. Cardiac imaging plays a crucial role in identifying cardioembolic causes of stroke, with early and accurate identification affecting treatment, preventing recurrence, and reducing stroke incidence. Echocardiography serves as the mainstay of cardiac evaluation. Transthoracic echocardiography (TTE) is the first line in the basic evaluation of structural heart disorders, valvular disease, vegetations, and intraventricular thrombus. It can be used to measure chamber size and systolic/diastolic function. Trans-oesophageal echocardiography (TOE) yields better results in identifying potential cardioembolic sources of stroke and should be strongly considered, especially if TTE does not yield adequate results. Cardiac computed tomography and cardiac magnetic resonance imaging provide better soft tissue characterisation, high-grade anatomical information, spatial and temporal visualisation, and image reconstruction in multiple planes, especially with contrast. These techniques are useful in cases of inconclusive echocardiograms and can be used to detect and characterise valvular lesions, thrombi, fibrosis, cardiomyopathies, and aortic plaques. Nuclear imaging is not routinely used, but it can be used to assess left-ventricular perfusion, function, and dimensions and may be useful in cases of infective endocarditis. Its use should be considered on a case-by-case basis. The accuracy of each imaging modality depends on the likely source of cardioembolism, and the choice of imaging approach should be tailored to individual patients.

Stroke in mitral valve prolapse: risk factors and left atrial function in cryptogenic versus non-cryptogenic ischemic subtypes

Background and purpose

Mitral valve prolapse (MVP) has been associated with an increased risk of ischemic stroke. Older age, thicker mitral leaflets, and significant mitral regurgitation (MR) leading to atrial fibrillation have been traditionally considered risk factors for ischemic stroke in MVP. However, specific risk factors for MVP-stroke subtypes are not well defined. The aim of this study is to evaluate clinical and echocardiographic parameters, including left atrial (LA) function, in MVP with cryptogenic (C) vs. non-cryptogenic (NC) stroke.

Methods

In this case-control matched study, MVPs were identified in consecutive echocardiograms obtained after a stroke from January 2013 to December2016 at the University of California, San Francisco. MVP was defined as leaflet displacement ≥2 mm in the parasternal long-axis view at end-systole. Age/gender matched MVPs without stroke and healthy controls without MVP were also identified. We analyzed LA end-systolic/diastolic volume index, emptying fraction (LAEF), function index (LAFI), and global longitudinal strain in all MVPs and controls. We also measured left ventricular (LV) volume indexes, mass index, ejection fraction (EF), degree of MR and leaflet thickness.

Results

We identified a total of 30 MVPs (age 70 ± 12, 50% females) with stroke (11 with C- and 19 with NC-stroke), 20 age/gender matched MVPs without a stroke and 16 controls. MVPs without stroke had lower BMI, less hypertension but more MR (≥moderate in 45% vs. 17%), more abnormal LA function (lower LAEF, LAFI) and larger LV volumes/mass (all p < 0.05) when compared to MVPs with stroke. Leaflet thickness was overall mild (<3 mm) and similar in the 2 groups. Within the MVP stroke group, NC-stroke had higher BMI, more hypertension and more atrial fibrillation compared to C-stroke. In the variables tested, patients with C-stroke did not differ from controls.

Conclusions

MVP-related MR may be protective against stroke despite abnormal LA function. Risk of NC-stroke in MVP is related to common stroke risk factors rather than mitral valve leaflet thickness. The etiology of C-stroke in MVP warrants further studies.

Epidemiology of young stroke in the ludhiana population-based stroke registry

Objective:

The objective of the study was to determine incidence, risk factors, and short-term outcomes of young stroke in Ludhiana city, Northwest India.

Methods:

Data were collected on first-ever stroke in patients of age ≥18 years, from hospitals, diagnostic imaging centers, general practitioners, and municipal corporation during March 2011–March 2013 in Ludhiana city, using the World Health Organization Stepwise Approach to Surveillance (WHO STEPS). Outcome was documented using the modified Rankin Scale at 28 days.

Results:

Of 2948 patients, 700 (24%) were in the age group 18–49 years. Annual incidence in this age group was 46/100,000 person-years (95% confidence interval [CI], 41–51/100,000). Hypertension (84%), diabetes mellitus (48%), and atrial fibrillation (AF) (12%) were found more common in >49 years age group, as compared with 18–49 years age group. Drug abuse (8.7% vs. 6% in age >49 years; P = 0.04) and tobacco intake (8.7% vs. 5.6% in age >49 years; P = 0.02) was more common in young people, that is, 18–49 years age group in comparison to older patients, >49 years age group. Recovery was better in younger subjects (60% vs. 46% in age >49 years P < 0.001). In a multivariable analysis, younger people were more often literate (odds ratio [OR] 2.52; 95% CI, 1.68–3.77; P < 0.001), employed (OR 3.92; 95% CI, 2.20–5.21; P < 0.001), and 374 (60%) had good clinical outcome, modified Rankin Scale <2 at 28 days follow-up as compared with 938 (46%) older patients (OR 1.52; 95% CI, 1.15–2.00; P = 0.003).

Conclusion:

Hypertension, diabetes mellitus, drug addiction, and tobacco intake were significantly associated with young stroke. Outcome was also better in younger people.

Mitral Valve Prolapse and Its Motley Crew-Syndromic Prevalence, Pathophysiology, and Progression of a Common Heart Condition

Mitral valve prolapse (MVP) is a commonly occurring heart condition defined by enlargement and superior displacement of the mitral valve leaflet(s) during systole. Although commonly seen as a standalone disorder, MVP has also been described in case reports and small studies of patients with various genetic syndromes. In this review, we analyzed the prevalence of MVP within syndromes where an association to MVP has previously been reported. We further discussed the shared biological pathways that cause MVP in these syndromes, as well as how MVP in turn causes a diverse array of cardiac and noncardiac complications. We found 105 studies that identified patients with mitral valve anomalies within 18 different genetic, developmental, and connective tissue diseases. We show that some disorders previously believed to have an increased prevalence of MVP, including osteogenesis imperfecta, fragile X syndrome, Down syndrome, and Pseudoxanthoma elasticum, have few to no studies that use up-to-date diagnostic criteria for the disease and therefore may be overestimating the prevalence of MVP within the syndrome. Additionally, we highlight that in contrast to early studies describing MVP as a benign entity, the clinical course experienced by patients can be heterogeneous and may cause significant cardiovascular morbidity and mortality. Currently only surgical correction of MVP is curative, but it is reserved for severe cases in which irreversible complications of MVP may already be established; therefore, a review of clinical guidelines to allow for earlier surgical intervention may be warranted to lower cardiovascular risk in patients with MVP.

Mitral Prolapse: An Old Mysterious Entity - The Incremental Role of Multimodality Imaging in Sports Eligibility

Mitral valve prolapse is generally a benign condition characterized by fibromyxomatous changes of the mitral leaflet with displacement into the left atrium and late-systolic regurgitation. Although it is an old clinical entity, it still arouses perplexity in diagnosis and clinical management. Complications, such as mitral regurgitation (MR), atrial fibrillation, congestive heart failure, endocarditis, ventricular arrhythmias, and sudden cardiac death (SCD), have been reported. A large proportion of the overall causes of SCD in young competitive athletes is explained by mitral valve prolapse. Recent studies have shown the fibrosis of the papillary muscles and inferobasal left ventricular wall in mitral valve prolapse, suggesting a possible origin of ventricular fatal arrhythmias. Athletes with mitral valve prolapse and MR should undergo annual evaluations including physical examination, echocardiogram, and exercise stress testing to evaluate the cardiovascular risks of competitive sports and obtain the eligibility. In this setting, multimodality imaging techniques – echocardiography, cardiac magnetic resonance, and cardiac computed tomography – should provide a broad spectrum of information, from diagnosis to clinical management of the major clinical profiles of the disease.

Progress in Clinical Neurosciences: Migraine-Stroke: A Causal Relationship, but Which Direction?

A significant association between migraine and ischemic stroke has been demonstrated in population and case-control studies. The risk of ischemic stroke appears to be higher in migraine with aura (MWA) than migraine without aura (MwoA). Migraine-stroke comprises a number of distinct entities, including migrainous infarction, in which ischemic stroke occurs during an attack of MWA and migraine-related stroke, in which the causal link is less clear. Migrainous infarction accounts for only one-third of migraine-stroke, strokes may occur during attacks of MwoA, and a number of cerebrovascular disorders may present as MWA or MwoA. Migraine may occur as a consequence of conditions that are known to cause stroke; therefore it remains to be determined whether migraine predisposes to stroke in the absence of any known disease associations, if it is an epiphenomenon of an underlying stroke diathesis, or if it requires the presence of another stroke risk factor to produce cerebral ischemia. Furthermore, it is unclear if ischemia results in migraine more often than migraine results in ischemia. Careful clinical studies that evaluate this bidirectional relationship are needed to determine why migraine patients are subject to a higher risk of ischemic stroke.

Microembolus detection by transcranial Doppler sonography: review of the literature

Transcranial Doppler can detect microembolic signals which are characterized by unidirectional high intensity increase, short duration, random occurrence, and a “whistling” sound. Microembolic signals have been detected in a number of clinical settings: carotid artery stenosis, aortic arch plaques, atrial fibrillation, myocardial infarction, prosthetic heart valves, patent foramen ovale, valvular stenosis, during invasive procedures (angiography, percutaneous transluminal angioplasty), surgery (carotid, cardiopulmonary bypass, orthopedic), and in certain systemic diseases. Microembolic signals are frequent in large artery disease, less commonly detected in cardioembolic stroke, and infrequent in lacunar stroke. This article provides an overview about the current state of technical and clinical aspects of microembolus detection.

Population-based study of the relationship between atherosclerotic aortic debris and cerebrovascular ischemic events

OBJECTIVE

To assess the validity of the suggestion that protruding atheromatous material in the thoracic aorta is an important cause of cerebrovascular ischemic events (CIEs) (ie, transient ischemic attack or ischemic stroke).

METHODS

This case-control study of Olmsted County, Minnesota, residents who underwent transesophageal echocardiography (TEE) from 1993 to 1997 included controls without CIE randomly selected from the population, controls without CIE referred for TEE because of cardiac disease, cases with incident CIE of obvious cause (noncryptogenic), and cases with incident CIE of uncertain cause (cryptogenic).

RESULTS

Of the 1135 subjects, 520 were randomly selected controls without CIE, 329 were controls without CIE referred for TEE, 159 were noncryptogenic CIE cases, and 127 were cryptogenic CIE cases. Complex atherosclerotic aortic debris in ascending and transverse segments of the arch was detected in 8 randomly selected controls (1.5%), 13 referred controls (4.0%), and 15 noncryptogenic (9.4%) and 4 cryptogenic (3.1%) CIE cases. After adjusting for age, sex, hypertension, smoking, atrial fibrillation, valvular heart disease, congestive heart failure, and atherosclerosis other than in the thoracic aorta, complex atherosclerotic aortic debris was not significantly associated with group status. With randomly selected controls as the referent group, odds ratios (95% confidence intervals) were 1.72 (0.61-4.87) for referred controls, 3.16 (1.18-8.51) for noncryptogenic CIE cases, and 1.39 (0.39-4.88) for cryptogenic CIE cases.

CONCLUSIONS

Complex atherosclerotic aortic debris is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack but is a marker for generalized atherosclerosis and well-established atherosclerotic and cardioembolic mechanisms of cerebral ischemia. Embolization from the aorta is not a common mechanism of ischemic stroke or transient ischemic attack.

Clinical significance of microembolus detection by transcranial Doppler sonography in cardiovascular clinical conditions

Transcranial Doppler can detect microembolic signals, which are characterized by unidirectional high intensity increase, short duration, and random occurrence, producing a "whistling" sound. Microembolic signals have been proven to represent solid or gaseous particles within the blood flow. Microemboli have been detected in a number of clinical cardiovascular settings: carotid artery stenosis, aortic arch plaques, atrial fibrillation, myocardial infarction, prosthetic heart valves, patent foramen ovale, valvular stenosis, during invasive procedures (angiography, percutaneous transluminal angioplasty) and surgery (carotid, cardiopulmonary bypass). Despite numerous studies performed so far, clinical significance of microembolic signals is still unclear. This article provides an overview of the development and current state of technical and clinical aspects of microembolus detection.

Silent cerebral infarct in patients with mitral valve prolapse

It is still not clear whether mitral valve prolapse (MVP) is a risk factor for ischemic stroke. The aim of this study was to evaluate whether uncomplicated MVP is a risk factor for silent cerebral ischemic events. Fifty-two patients with uncomplicated MVP and 46 control subjects without MVP were included in the study. All subjects were evaluated for silent cerebral infarct (SCI) with a magnetic resonance imaging. Five (9.6%) of the patients who had MVP but no other risk factors for ischemic cerebral events had SCI. The results suggest that uncomplicated MVP is a risk factor for SCI, and that patients with MVP should receive anti-platelet-aggregating drugs.

Outcomes among valvular heart disease patients experiencing ischemic stroke or transient ischemic attack in Olmsted County, Minnesota

OBJECTIVE

To estimate the rates and predictors of survival and recurrence among residents of Olmsted County, Minnesota, who received an Initial diagnosis based on 2-dimensional color Doppler echocardiography of moderate or severe mitral or aortic stenosis or regurgitation and who experienced a first ischemic stroke, transient ischemic attack (TIA), or amaurosis fugax.

PATIENTS AND METHODS

At the Mayo Clinic in Rochester, Minn, we used the resources of the Rochester Epidemiology Project to identify Individuals who met the criteria for inclusion in the study and to verify exclusion criteria. The study included all residents of Olmsted County, Minnesota, who experienced a first Ischemic stroke, TIA, or amaurosis fugax within 30 days of or subsequent to receiving a first-time 2-dimensional color Doppler echocardlography-based diagnosis of moderate or severe mitral or aortic stenosis or regurgitation between January 1, 1985, and December 31, 1992. The Kaplan-Meier product-limit method was used to estimate the rates of subsequent stroke and death after the ischemic stroke, TIA, or amaurosis fugax. The Cox proportional hazards model was used to assess the effect of several potential risk factors on subsequent stroke occurrence and death.

RESULTS

For the 125 patients in the study, the Kaplan-Meier estimates of the risk of death and the risk of stroke at 2-year follow-up were 38.6% (95% confidence interval [CI], 29.9%-47.5%) and 18.5% (95% CI, 10.0%-27.0%), respectively. Compared with the general population, death rates were significantly Increased (standardized mortality ratio = 1.75; 95% CI, 1.38-2.19; P < .001) but rates of subsequent stroke occurrence were not (standardized morbidity ratio = 1.20; 95% CI, 0.75-1.84; P = .40). After adjustment for age, sex, and cardiac comorbidity, neither the type nor severity of valvular heart disease was an independent determinant of survival or subsequent stroke occurrence.

CONCLUSIONS

Patients with mitral or aortic valvular heart disease who experience Ischemic stroke, TIA, or amaurosis fugax have Increased rates of death, but not recurrent stroke, compared with expected rates. Other cardiovascular risk factors are more important determinants of survival In these patients than the type or echocardiographic severity of the valvular heart disease.

Mitral valve prolapse

Mitral valve prolapse is a common valvular abnormality that is the most common cause of severe non-ischaemic mitral regurgitation in the USA. The overall prognosis of patients with mitral valve prolapse is excellent, but a small subset will develop serious complications, including infective endocarditis, sudden cardiac death, and severe mitral regurgitation. We present a comprehensive review of mitral valve prolapse, examining normal mitral anatomy, the clinical and echocardiographic features of mitral valve prolapse, and the pathophysiology and genetics of the disorder. We discuss the contemporary management of both asymptomatic and symptomatic prolapse, with particular attention to the timing and technique of surgical repair. We conclude that echocardiography is the method of choice for diagnosing mitral valve prolapse, that clinical and echocardiographic features can predict which patients with prolapse are at highest risk for complications, and that mitral valve repair is the treatment of choice for symptomatic prolapse.

An evidence-based causative classification system for acute ischemic stroke

Regular, evidence-based assignment of patients to etiologic stroke categories is essential to enable valid comparison among studies. We designed an algorithm (SSS-TOAST) that incorporated recent advances in stroke imaging and epidemiology to identify the most probable TOAST category in the presence of evidence for multiple mechanisms. Based on the weight of evidence, each TOAST subtype was subdivided into 3 subcategories as "evident", "probable", or "possible". Classification into the subcategories was determined via predefined specific clinical and imaging criteria. These criteria included published risks of ischemic stroke from various mechanisms and published reports of the strength of associations between clinical and imaging features and particular stroke mechanisms. Two neurologists independently assessed 50 consecutively admitted patients with acute ischemic stroke through reviews of abstracted data from medical records. The number of patients classified as "undetermined-unclassified" per the original TOAST system decreased from 38-40% to 4% using the SSS-TOAST system. The kappa value for inter-examiner reliability was 0.78 and 0.90 for the original TOAST and SSS-TOAST respectively. The SSS-TOAST system successfully classifies patients with acute ischemic stroke into determined etiologic categories without sacrificing reliability. The SSS-TOAST is a dynamic algorithm that can accommodate modifications as new epidemiological data accumulate and diagnostic techniques advance.

Late outcomes of mitral valve repair for floppy valves: Implications for asymptomatic patients

OBJECTIVES

We sought to evaluate the long-term results of mitral valve repair in patients with mitral regurgitation caused by floppy mitral valves and compare the outcomes of asymptomatic patients with those of symptomatic patients.

METHODS

A retrospective review of 488 consecutive patients who had mitral valve repair for floppy mitral valve disclosed 199 patients who were asymptomatic or had minimal symptoms and 289 patients who were symptomatic at the time of the operation. Asymptomatic patients were younger, had better ventricular function, had a lower incidence of coronary artery disease, and had higher rates of atrial fibrillation than symptomatic patients.

RESULTS

Survival at 15 years was 61% for all patients. Survival was 76% for asymptomatic patients, which was identical to that for the general population matched for age and sex, whereas the survival of symptomatic patients was 53% and significantly lower than that of the general population. Cox regression analyses validated by means of bootstrap methodology identified the following predictors of late death: age by increments of 5 years (risk ratio = 1.2), New York Heart Association functional classes 3 and 4 (risk ratio = 3.0), left ventricular ejection fraction of less than 40% (risk ratio = 2.7), preoperative stroke or transient ischemic attack (risk ratio = 3.1), previous cardiac operation (risk ratio = 4.6), and severe chronic obstructive pulmonary disease (risk ratio = 3.1). Freedom from reoperation at 15 years was 91%, and it was similar for asymptomatic and symptomatic patients. Freedom from mitral regurgitation of greater than 2+ at 15 years was 85% for all patients, 96% for asymptomatic patients, and 76% for symptomatic patients.

CONCLUSIONS

This study supports the recommendation of surgical intervention in asymptomatic patients with mitral regurgitation caused by a floppy mitral valve if mitral valve repair is feasible and associated with low operative mortality and morbidity.

Cardioembolic stroke: an update

Embolism of cardiac origin accounts for about one fifth of ischaemic strokes. Strokes due to cardioembolism are in general severe and prone to early recurrence. The risk of long term recurrence and mortality are high after a cardioembolic stroke. Cardioembolism can be reliably predicted on clinical grounds but is difficult to document. MRI, transcranial doppler, echocardiogram, Holter monitoring, and electrophysiological studies increase our ability to identify the source of cardioembolism. Non-valvular atrial fibrillation is the commonest cause of cardioembolic stroke. Despite its enormous preventive potential, continuous oral anticoagulation is prescribed for less than half of patients with atrial fibrillation who have risk factors for cardioembolism and no contraindications for anticoagulation. Alternatives to oral anticoagulation in this setting include safer and easier to use antithrombotic drugs and definitive treatment of atrial fibrillation. Available evidence does not support routine immediate anticoagulation of acute cardioembolic stroke.

Stroke prevention: cardiac and carotid-related stroke

The aim of this article is to discuss cardiac sources of stroke as well as the management of symptomatic and asymptomatic carotid stenosis. The authors detail the risks of cardioembolic stroke in the following conditions: aortic arch atheroma, atrial fibrillation, atrial myxoma, atrial septal aneurysm, dilated cardiomyopathy, infective endocarditis, left ventricular thrombus, mitral annular calcification, mitral valve prolapse, patent foramen ovale, prosthetic heart valves, valvular strands, and the optimal medical management for these conditions. The indications for carotid endarterectomy, angioplasty, and stenting are also outlined.

Role of routine transthoracic echocardiography in evaluation and management of stroke

OBJECTIVE

To determine the value of routine transthoracic echocardiography in patients with cerebral ischemia without known cardiac disease.

DESIGN

The literature from 1990 to 1995 was searched and relevant bibliographies from these papers reviewed. Articles reporting the prevalence and/or risk of stroke for myxoma, vegetation, mitral stenosis, left atrial thrombus, left ventricular thrombus or cardiomyopathy, patent foramen ovale, and atrial septal aneurysm were used. Prevalences and recurrent stroke risk were examined for adult patients less than and greater than 45 years.

RESULTS

Both the prevalence of transthoracic echocardiographic findings and recurrent risk of stroke differ by age. The finding of a patent foramen ovale can be expected in nearly half of younger patients with stroke, whilst transthoracic echo can be expected to yield no relevant lesion in three quarters of patients > 45 years. Warfarin anticoagulation appears beneficial in patients with mitral stenosis, left atrial thrombus, left ventricular thrombus, and left ventricular dysfunction, but is of unproven benefit for patent foramen ovale, atrial septal aneurysm, or in the absence of a risk-associated abnormality.

CONCLUSION

For most transthoracic echo findings in stroke, optimal management strategies have not been well defined. Future research is needed to evaluate the appropriate therapeutic approaches.

Correlations of flow velocity changes during mental activity and recovery from aphasia in ischemic stroke

Mean flow velocity in the middle cerebral arteries (MCAs) during a rest period and during execution of a word-fluency task were measured by means of bilateral transcranial Doppler ultrasonography in 26 stroke patients with Broca's aphasia and in 25 healthy controls. Changes in flow velocity were calculated as percentage of increase from rest to mental activity. In patients, the evaluation was made within 21 days from onset of symptoms and after 2 months of speech therapy, when they were classified into two groups on the basis of extent of recovery from aphasia: absent or slight recovery (group 1, 10 patients) and good recovery (group 2, 16 patients). During the word-fluency task in the first evaluation, the increase in flow velocity in the left MCA was similar in controls and in group 2 patients. In both groups the increase was higher than in group 1 patients (p < 0.0001). Changes in mean flow velocity on the right side were slight and comparable in the three groups of study subjects. After speech therapy, group 1 patients showed a hemodynamic pattern on both sides similar to that observed in the first examination. In group 2 patients, comparison between values of the first and second evaluations showed that the increase of flow velocity in the left MCA was similar. On the right side, the increase was higher in the second than in the first examination (p < 0.01). These data further support the involvement of cerebral areas contralateral to the lesion in functional recovery after stroke. Moreover, the presence of an activation of areas in the lesioned hemisphere, soon after stroke onset, seems to be a predictor of recovery from aphasia.

Meta-analysis of the Hachinski Ischemic Score in pathologically verified dementias

Our objectives were to investigate the utility of the Hachinski Ischemic Score (HIS) in differentiating patients with pathologically verified Alzheimer's disease (AD), multi-infarct dementia (MID), and "mixed" (AD plus cerebrovascular disease) dementia, and to identify the specific items of the HIS that best discriminate those dementia subtypes. Investigators from six sites participated in a meta-analysis by contributing original clinical data, HIS, and pathologic diagnoses on 312 patients with dementia (AD, 191; MID, 80; and mixed, 41). Sensitivity and specificity of the HIS were calculated based on varied cutoffs using receiver-operator characteristic curves. Logistic regression analyses were performed to compare each pair of diagnostic groups to obtain the odds ratio (OR) for each HIS item. The mean HIS (+/- SD) was 5.4 +/- 4.5 and differed significantly among the groups (AD, 3.1 +/- 2.5; MID, 10.5 +/- 4.1; mixed, 7.7 +/- 4.3). Receiver-operator characteristic curves showed that the best cutoff was < or = 4 for AD and > or = 7 for MID, as originally proposed, with a sensitivity of 89.0% and a specificity of 89.3%. For the comparison of MID versus mixed the sensitivity was 93.1% and the specificity was 17.2%, whereas for AD versus mixed the sensitivity was 83.8% and the specificity was 29.4%. HIS items distinguishing MID from AD were stepwise deterioration (OR, 6.06), fluctuating course (OR, 7.60), hypertension (OR, 4.30), history of stroke (OR, 4.30), and focal neurologic symptoms (OR, 4.40). Only stepwise deterioration (OR, 3.97) and emotional incontinence (OR, 3.39) distinguished MID from mixed, and only fluctuating course (OR, 0.20) and history of stroke (OR, 0.08) distinguished AD from mixed. Our findings suggest that the HIS performed well in the differentiation between AD and MID, the purpose for which it was originally designed, but that the clinical diagnosis of mixed dementia remains difficult. Further prospective studies of the HIS should include additional clinical and neuroimaging variables to permit objective refinement of the scale and improve its ability to identify patients with mixed dementia.

The impact of apolipoprotein E4 on cause of death in Alzheimer's disease

OBJECTIVE

We tested the hypothesis that the apolipoprotein E epsilon 4 (apoE4) allele is associated with an increased proportion of vascular-related mortality in Alzheimer's disease (AD).

BACKGROUND

ApoE4 is associated with an increased risk of developing AD, with an earlier onset, and may predispose to vascular dementia as well. In the general population, apoE4 has been associated with increased coronary artery disease and shorter lifespan. There is a paucity of data regarding the effect of the apolipoprotein E (apoE) genotype upon the contributing causes of death in AD.

METHODS

Death certificates of 114 AD cases were reviewed blind to apoE genotype. Deaths due to ischemic heart disease (IHD), cerebrovascular disease (CVD), vascular disease (either IHD or CVD), pneumonia, and other causes were analyzed as a function of apoE genotype. Logistic regression analyses were employed to control for age and gender effects.

RESULTS

The likelihood of vascular disease contributing to death increased in association with the epsilon 4 allele (29% in cases without an epsilon 4 allele, 43% in cases with one epsilon 4 allele, 53% in epsilon 4/4 homozygous cases; p = 0.035 after corrections for age and gender). This increase appeared largely due to an increase in ischemic heart disease, which was reported more frequently on death certificates of cases with one or more epsilon 4 allele (adjusted odds ratio [OR] = 1.85 per epsilon 4 allele; p < 0.05). There were nonsignificant trends for apoE4 to be associated with increased mortality related to cerebrovascular disease (OR = 1.45) and decreased mortality related to pneumonia (OR = 0.77) and AD itself (OR = 0.72). The epsilon 4/4 cases had significantly earlier age of onset (mean = 64.5 yr), earlier death, and longer duration of disease (mean = 10.1 yr). Cases with one or more epsilon 4 allele tended to have lower mean MMSE scores prior to death (6.6 versus 9.5) and were more often female (54% versus 45%).

CONCLUSIONS

The apoE4 allele appears to increase the risk of vascular and ischemic heart disease-related death in patients with AD.