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H Mast

Publications and source records attributed to H Mast.

At least 37 records · Page 2Linked to original sources
PubMed2000

Incident hemorrhage risk of brain arteriovenous malformations located in the arterial borderzones.

BACKGROUND AND PURPOSE: We sought to assess the relative risk of hemorrhagic presentation of brain arteriovenous malformations (AVMs) located in the arterial borderzone territories. METHODS: The 464 consecutive, prospectively enrolled patients from the New York AVM Databank were analyzed. AVM borderzone location was coded positive when the malformation was supplied by branches of at least 2 of the major circle of Willis arteries (anterior, middle, and/or posterior cerebral arteries). AVMs fed by branches of only 1 major pial or any other single artery served as a comparison group. Clinical presentation (diagnostic event) was categorized as (1) intracranial hemorrhage, proven by brain imaging, or (2) seizure, focal neurological deficit, headache, or other event with no signs of AVM hemorrhage on brain imaging. RESULTS: In 48% (n=222) of the patients, AVMs were located in the arterial borderzone territories; in 52% (n=242) a non-borderzone location was found. Hemorrhage was the presenting symptom in 44% (n=205); 28% (n=132) presented with seizures, 11% (n=52) with headaches, 7% (n=34) with a neurological deficit, and 9% (n=41) with other or no AVM-related symptoms. The frequency of incident AVM hemorrhage was significantly lower in borderzone AVMs (27%, n=61) than in non-borderzone malformations (60%, n=144; P:<0.001). This difference remained significant in a multivariate model controlling for age, sex, AVM size, deep venous drainage, and presence of aneurysms (odds ratio, 0.4; 95% CI, 0.25 to 0.66). CONCLUSIONS: Our findings suggest that borderzone location is an independent determinant for a lower risk of AVM hemorrhage at initial presentation.

Adult↗
PubMed2000

Demographic, morphological, and clinical characteristics of 1289 patients with brain arteriovenous malformation.

BACKGROUND AND PURPOSE: The purpose of this study was to assess demographic, clinical, and morphological characteristics of patients with brain arteriovenous malformations (AVMs). METHODS: Prospectively collected data of 1289 consecutive AVM patients from 3 independent databases (1 multicenter [Berlin/Paris/Middle and Far East, n=662] and 2 single centers [New York, n=337, and Toronto, n=290]) were analyzed. The variables assessed were age at diagnosis, sex, AVM size, AVM drainage pattern, AVM location in functionally important brain areas ("eloquence"), and type of presentation (hemorrhage, seizure, chronic headache, or focal neurologic deficit). Comparisons were made by ANOVA, contingency tables, and log-linear models. RESULTS: Overall, mean age at diagnosis was 31.2 years (95% CI 30.2 to 32.2 years), and 45% of the patients were female (95% CI 42% to 47%). AVM maximum diameter was <3 cm in 38% (95% CI 35% to 41%). Deep venous drainage was present in 55% (95% CI 52% to 59%). An eloquent AVM location was described in 71% (95% CI 69% to 74%). AVM hemorrhage occurred in 53% (95% CI 51% to 56%). Generalized or focal seizures were described in 30% (95% CI 27% to 33%) and 10% (95% CI 8% to 12%), respectively. Chronic headache was recorded in 14% (95% CI 12% to 16%). Persistent neurological deficits were found in 7% (95% CI 6% to 9%), and progressive neurological deficits in 5% (95% CI 4% to 6%). Significant differences between centers were found for age (P<0.001), sex (P=0.04), eloquence (P=0.04), size (P<0.001), hemorrhage (P=0.006), persistent neurological deficit (P<0.001), and reversible neurological deficit (P=0.013). The intercenter difference found for hemorrhage frequency did not remain after adjustment for AVM size. CONCLUSIONS: Baseline characteristics differed considerably between centers. The differences found in patient age and AVM size may be explained by center-specific referral patterns and the influence of access to treatment resources, whereas those found for other characteristics may be attributable to center-specific definitions. Analysis of natural history data from tertiary referral center databases may be improved by consistent definitions applicable to the entire population of AVM patients.

Adolescent↗
PubMed1999

Dysarthria during basilar artery balloon occlusion.

A 49-year-old woman presenting with recurrent, reversible brainstem symptoms and a distal basilar artery aneurysm underwent balloon test occlusion. Five minutes after balloon inflation she developed a reversible isolated dysarthria. Despite failing the test occlusion (and after an additional brainstem event), the patient underwent surgery with placement of a clip across the basilar artery. The operation was tolerated without complication. The authors conclude that 1) pure dysarthria may be a symptom of temporary basilar artery occlusion and 2) balloon testing may overestimate the risk of basilar artery clipping.

Angioplasty, Balloon↗
PubMed1999

[In Process Citation]

BACKGROUND: We investigated the association of cigarette smoking with high-grade carotid artery stenosis in patients with ischemic stroke and transient ischemic attacks. METHODS: Prospectively collected data from 404 patients with focal brain ischemia were used for a cross-sectional study estimating the association between cigarette smoking and high-grade carotid artery stenosis (diagnosed by Doppler-ultrasound and defined as a luminal narrowing of > or = 70%). Cerebral ischemia patients with normal sonographic findings served as a comparison group. Multivariate logistic regression models were used for statistical tests to determine the association between smoking and high-grade carotid stenosis. Age, gender, hypertension, diabetes mellitus, hypercholesterolemia and co-existing heart disease (myocardial infarction, angina, heart failure) were considered potential confounders. RESULTS: High-grade carotid stenoses were found in 25% (n = 101) of the patients; 39% (n = 156) were classified as smokers. Smoking (odds ratio 3.6, 95% confidence interval [CI] 2.2 to 5.8), hypercholesterolemia (odds ratio 1.8; CI 1.1 to 2.8) and preexisting heart disease (odds ratio 1.7; CI 1.1 to 2.7) were significantly associated with carotid stenosis > or = 70%. The impact of smoking augmented with increasing degree of stenosis (odds ratio for stenoses > or = 80%: 4.3, CI 2.3 to 7.7), whereas the association with hypercholesterolemia, and co-existing heart disease decreased in strength for stenoses greater than 80%. Hypertension and diabetes mellitus were not found to be significantly with high-grade carotid artery stenoses. CONCLUSION: Smoking is an independent determinant of severe carotid artery stenosis in patients with focal cerebral ischemia.

Journal Article↗
PubMed1999

Interrater reliability of plaque morphology classification in patients with severe carotid artery stenosis.

OBJECTIVE: Ultrasonographic assessment of carotid artery plaque morphology is widely used to identify patients at high risk for stroke. However, the reliability of plaque analysis in high-grade stenosis is uncertain. We determined the interrater reliability of sonographic plaque morphology analysis in patients with severe carotid artery stenosis. MATERIALS AND METHODS: Duplex Doppler was performed on 114 patients with 80-99% stenosis of the internal carotid artery using a Siemens Quantum 2000 D with a handheld 7.5 MHz transducer. B-mode pictures with and without color coding were printed on a Sony color video printer UP-5000 W. Three raters independently evaluated plaque echolucency, heterogeneity, calcification, and surface structure. Interrater agreement was calculated by a jackknife procedure generating kappa values and two-sided 95% confidence intervals. RESULTS: Kappa values and 95% confidence intervals were 0.05 (-0.07 to 0.16) for plaque surface structure, 0.15 (0.02 to 0.28) for plaque heterogeneity, 0.18 (0.09 to 0.29) for plaque echogenicity, and 0.29 (0.19 to 0.39) for plaque calcification. The upper bounds of all of the confidence intervals were below the 0.40 level suggested for minimal reliability. CONCLUSION: The low interrater agreement indicated that unaided visual assessment of static B-mode pictures to assess plaque morphology in patients with severe carotid artery stenosis is not reliable. Other evaluation procedures and standardized criteria, as yet undeveloped, are needed to improve reliability.

Arteriosclerosis↗
PubMed1999

Cerebral hemorrhage after systemic fibrinolysis in a patient with severe carotid artery stenosis.

Despite the beneficial effect of systemic fibrinolysis in treatment within 3 hours from ischemic stroke onset, the unpredicted occurrence of intracerebral hemorrhage remains a risk from such therapy. Few data exist defining patients at risk for this outcome. We report clinical and neuropathological data on a patient fulfilling NINDS rt-PA study and ECASS-2 inclusion criteria with an acute stroke due to high-grade carotid artery stenosis and preceded by amaurosis fugax. He died from an intracerebral hemorrhage after systemic fibrinolysis. The fatal outcome adds support to recommendations that rapid Doppler-sonographic evaluation of the extra- and intracranial vascular status be undertaken before systemic rt-PA is implemented in acute ischemic stroke.

Adult↗
PubMed1998

[Effect of cardiac embolism sources on origin of territorial cerebral infarcts].

BACKGROUND AND PURPOSE: To test the association of cardiac sources of embolism with territorial type brain infarcts. METHODS: From a prospective cerebral ischemia data base the 106 consecutive patients with territorial type cerebral infarcts on computerized tomography were analyzed. The 85 consecutive patients with lacunar lesions served as a comparison group. The association of cardiac sources of embolism with territorial types infarcts was assessed using univariate Chi Square tests and logistic regression models. Cardiac sources of embolism were defined as:atrial fibrillation, left cardiac thrombi, valvular vegetations, wall motion and valvular abnormalities, left atrial enlargement, open foramen ovale, septal aneurysm, mitral valve prolaps, and aortic arch atherothrombosis (all findings--except for atrial fibrillation--assessed by echocardiography). RESULTS: Atrial fibrillation was significantly associated with territorial type infarcts (odds ratio 2.2, 95% confidence interval 1.01-4.8). This effect was independent of additional cardiac diseases, other cardiac abnormalities, carotid artery stenosis, and patient age. Most likely due to the small sample size, left cardiac thrombi only showed a non-significant trend towards an association with territorial infarcts (odds ratio 3.0, 95% confidence interval 0.7-12.3). The rate of all other cardiac findings did not differ significantly between the comparison groups. CONCLUSION: Atrial fibrillation and cardiac thrombi showed an association with territorial type infarcts. Other so-called cardiac sources of embolism--except for mechanical valves and bacterial endocarditis which were not represented in our sample--revealed no clinically relevant association with embolic brain infarct pattern.

Adult↗
PubMed1998

[Therapy of cerebral arteriovenous malformations].

The rapid development of modern endovascular, microsurgical, and radiation therapies has considerably expanded the treatment options for encephalic arteriovenous malformations (AVMs). Surgery has the longest history. Single or staged intravascular procedures (embolizations) using fast-acting glues, sclerotic agents, and thrombogenic coils serve to reduce the size of AVM to that suitable for extirpation and may reduce the risk of surgery. Radiation ("gamma-knife") therapy, most frequently used in small, non-operable AVMs, is also viewed by some authors as an alternative or even superior tool in small, operable malformations. Partial embolization to reduce the mass-effect of space-occupying AVMs, to reverse diaschisis, and to treat AVM-related seizure disorders is being discussed and practiced. Given the in part competing or even controversial options, the selection of optimal treatment for AVM patients is becoming increasingly difficult. Current management is impeded by the paucity of information on the exact risks of invasive therapies and by insufficient criteria for identifying patients at risk of spontaneous bleeding during the natural course, including the seriousness of such hemorrhage.

Cerebral Angiography↗
PubMed1998

Theoretical modelling of arteriovenous malformation rupture risk: a feasibility and validation study.

PURPOSE: To explore the feasibility of using a theoretical computational model to simulate the risk of spontaneous arteriovenous malformation (AVM) haemorrhage. METHODS: Data from 12 patients were collected from a prospective databank which documented the angioarchitecture and morphological characteristics of the AVM and the feeding mean arterial pressure (FMAP) measured during initial superselective angiography prior to any treatment. Using the data, a computational model of the cerebral circulation and the AVM was constructed for each patient (patient-specific model). Two model risk (Risk(model)) calculations (haemodynamic- and structural-weighted estimates) were performed by using the patient-specific models. In our previously developed method of haemodynamic-weighted estimate, Risk(model) was calculated with the simulated intranidal pressures related to its maximal and minimal values. In the method of structural-weighted estimate developed and described in this paper, the vessel mechanical properties and probability calculation were considered in more detail than in the haemodynamic-weighted estimate. Risk(model) was then compared to experimentally determined risk which was calculated using a statistical method for determining the relative risk of having initially presented with AVM haemorrhage, termed Risk(exp). RESULTS: The Risk(model) calculated by both haemodynamic- and structural-weighted estimates correlated with experimental risks with chi2 = 6.0 and 0.64, respectively. The risks of the structural-weighted estimate were more correlated to experimental risks. CONCLUSIONS: Using two different approaches to the calculation of AVM haemorrhage risk, we found a general agreement with independent statistical estimates of haemorrhagic risk based on patient data. Computational approaches are feasible; future work can focus on specific pathomechanistic questions. Detailed patient-specific computational models can also be developed as an adjunct to individual patient risk assessment for risk-stratification purposes.

Cerebral Hemorrhage↗
PubMed1998

Cigarette smoking as a determinant of high-grade carotid artery stenosis in Hispanic, black, and white patients with stroke or transient ischemic attack.

BACKGROUND AND PURPOSE: We sought to investigate the association of cigarette smoking with high-grade carotid artery stenosis in Hispanic, black, and white patients with cerebral ischemia in two independent samples. METHODS: Prospectively collected data from the Northern Manhattan Stroke Study (NOMASS) (n=431) and the Berlin Cerebral Ischemia Databank (BCID) (n=483) were used separately for a cross-sectional study estimating the association between cigarette smoking and high-grade carotid stenosis (defined as a luminal narrowing of > or =60%, diagnosed by duplex and/or Doppler ultrasound). In both studies, cerebral ischemia patients with normal sonographic findings or nonstenosing plaques of their carotid arteries served as a comparison group. Multivariate logistic regression models were used for statistical tests to determine the association between smoking and the dependent variable for high-grade carotid stenosis. Age, sex, hypertension, diabetes, hypercholesterolemia, and race/ethnicity were considered potential confounders. Further analyses of the NOMASS data estimated the effect of the amount of cigarette use and the impact of race/ethnicity. RESULTS: High-grade carotid stenoses were found in 14% of the NOMASS and in 21% of the Berlin patients. In Berlin the entire sample was white, whereas in New York only 19% of the cohort were white. In both samples, smoking was independently associated with severe carotid stenosis (NOMASS: odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1 to 2.0; BCID: OR, 3.9; 95% CI, 2.4 to 6.4). Patients smoking 20 pack-years or more showed a significant association (OR, 2.0; 95% CI, 1.1 to 3.9), whereas no significant effect was found for lower amounts of cigarette use. In NOMASS, white smokers displayed a significant (OR, 3.2; 95% CI, 1.1 to 8.9) association with high-grade carotid stenosis, the association for black smokers was less strong, and no association was found among Hispanics. CONCLUSIONS: Smoking is an independent determinant of severe carotid artery stenosis in patients with focal cerebral ischemia. The association differs by race/ethnicity, with the greatest effect observed among whites.

Adult↗
PubMed1998

Morbidity of intracranial hemorrhage in patients with cerebral arteriovenous malformation.

BACKGROUND AND PURPOSE: Decisions on invasive arteriovenous malformation (AVM) treatment are currently based on natural-course risk estimates of AVM bleeding and assumptions on morbidity from cerebral hemorrhage in general. However, morbidity of AVM hemorrhage has rarely been reported. We sought to assess the morbidity of intracranial hemorrhage in patients with cerebral AVMs. METHODS: From a prospective AVM database, 119 patients were analyzed: 115 had a hemorrhage as the diagnostic event, and 27 of them suffered a second hemorrhage during follow-up; an additional 4 patients had other diagnostic symptoms but bled during follow-up. The type (parenchymal, subarachnoid, intraventricular) and location of AVM hemorrhage were determined by CT/MR brain imaging. Disability and neurological impairment were assessed with the Barthel Index, the Rankin Scale, and the National Institutes of Health Stroke Scale, with a mean follow-up time of 16.2 months. RESULTS: Of the 115 incident hemorrhages, 34 (30%) were subarachnoid, 27 (23%) parenchymal, 18 (16%) intraventricular, and 36 (31%) in combined locations. In 54 patients (47%; 95% confidence interval [CI], 38% to 56%) the incident hemorrhage resulted in no neurological deficit, and an additional 43 patients (37%; 95% CI, 28% to 46%) were independent in their daily activities (Rankin 1). Fifteen patients (13%; 95% CI, 7% to 19%) were moderately disabled (Rankin 2 or 3), and 3 (3%; 95% CI, 0% to 6%) were severely disabled (Rankin > or =4). Parenchymal hemorrhages were most likely to result in a neurological deficit (52%). Type and morbidity of hemorrhage during follow-up were similar to incident events. Twenty (74%) of 27 patients with both incident and follow-up hemorrhages were normal or independent (Rankin 0 or 1). None of the patients with a hemorrhage during follow-up died during the observation period. CONCLUSIONS: Hemorrhage from cerebral AVMs appears to have a lower morbidity than currently assumed. This finding encourages a reevaluation of the risks and benefits of invasive AVM treatment.

Activities of Daily Living↗
PubMed1998

Feeding artery pressure and venous drainage pattern are primary determinants of hemorrhage from cerebral arteriovenous malformations.

PURPOSE: The purpose of this study was to define the influence of feeding mean arterial pressure (FMAP) in conjunction with other morphological or clinical risk factors in determining the probability of hemorrhagic presentation in patients with cerebral arteriovenous malformations (AVMs). METHODS: Clinical and angiographic data from 340 patients with cerebral AVMs from a prospective database were reviewed. Patients were identified in whom FMAP was measured during superselective angiography. Additional variables analyzed included AVM size, location, nidus border, presence of aneurysms, and arterial supply and venous drainage patterns. The presence of arterial aneurysms was also correlated with site of bleeding on imaging studies. RESULTS: By univariate analysis, exclusively deep venous drainage, periventricular venous drainage, posterior fossa location, and FMAP predicted hemorrhagic presentation. When we used stepwise multiple logistic regression analysis in the cohort that had FMAP measurements (n = 129), only exclusively deep venous drainage (odds ratio [OR], 3.7; 95% confidence interval [CI], 1.4 to 9.8) and FMAP (OR, 1.4 per 10 mm Hg increase; 95% CI, 1.1 to 1.8) were independent predictors (P < 0.01) of hemorrhagic presentation; size, location, and the presence of aneurysms were not independent predictors. There was also no association (P = 0.23) between the presence of arterial aneurysms and subarachnoid hemorrhage. CONCLUSIONS: High arterial input pressure (FMAP) and venous outflow restriction (exclusively deep venous drainage) were the most powerful risk predictors for hemorrhagic AVM presentation. Our findings suggest that high intranidal pressure is more important than factors such as size, location, and the presence of arterial aneurysms in the pathophysiology of AVM hemorrhage.

Adult↗
PubMed1997

Cerebellar atrophy with basilar artery occlusion.

Small and large vessel occlusive disease leading to chronic cerebral ischemia and brain atrophy is a concept originating in the last century. The modern notion of acute brain infarct, however, appears to have eclipsed the idea of chronic hypoperfusion as an important factor in ischemic cerebral damage. We present a patient history featuring recurrent episodes of acute posterior circulation infratentorial ischemia in addition to a progressive cerebellar syndrome over a course of several years. Laboratory work-up including cerebral angiography, repeated CT and MR scanning revealed basilar artery occlusion, a pontine infarct and a subsequently developing cerebellar atrophy without signs of cerebellar infarction. Findings indicating causes of cerebellar atrophy other than ischemia could not be elicited. We offer the hypothesis that basilar artery occlusion, inducing subsequent chronic ischemia, is the most likely cause of the cerebellar atrophy observed in our case.

Adult↗
PubMed1997

Risk of spontaneous haemorrhage after diagnosis of cerebral arteriovenous malformation.

BACKGROUND: A small proportion of strokes are caused by cerebral arteriovenous malformations (AVM). Treatment to prevent intracranial haemorrhage itself carries risks, and untreated AVM may in many cases have a good prognosis. We investigated the risk of subsequent symptomatic bleeding in the clinical course of AVM in patients with and without an initial haemorrhage. METHODS: 281 unselected, consecutive, prospectively enrolled patients with cerebral AVM were grouped according to their initial clinical presentation--142 presented with and 139 without haemorrhage. The frequency of AVM haemorrhages during the subsequent clinical course (before the start of endovascular, surgical, or radiation treatment) in the two groups was compared by means of Kaplan-Meier life-tables, log-rank test, and multivariate proportional-hazards regression models. Haemorrhage was defined as a clinically symptomatic event with signs of acute bleeding on computed tomography or magnetic resonance brain imaging. FINDINGS: During mean follow-up of 8.5 months for the haemorrhage group and 11.9 months for the non-haemorrhage group, haemorrhages occurred in 18 (13%) of the former patients and in three (2%) of the latter (p=0.0002). The annual risk of haemorrhage was 17.8% and 2.2%, respectively. In the multivariate regression model, the adjusted hazard ratio for haemorrhage at initial presentation was 13.9 (95% CI 2.6-73.8; p=0.002). Deep venous drainage (hazard ratio 4.1 [1.2-14.9], p=0.029) and male sex (9.2 [2.1-41.3], p=0.004) were also significantly associated with subsequent haemorrhage, but no significant association was found for age or AVM size. The annual rate of spontaneous haemorrhage was 32.6% for men and 10.4% for women in the haemorrhage group compared with 3.3% for men and 1.3% for women in the non-haemorrhage group. Among patients with haemorrhage at initial presentation, the risk of haemorrhage fell from 32.9% in year 1 to 11.3% in subsequent years (34.2% to 31.0% in men; 31.1% to 5.5% in women). INTERPRETATION: In AVM, patients initially presenting with haemorrhage have a higher risk of subsequent bleeding than those presenting with other symptoms. The risk is higher in men than in women.

Adult↗
PubMed1997

[Association of hypertension and diabetes mellitus with microangiopathic cerebral infarct patterns].

OBJECTIVE: To test the hypothesis of a positive association of hypertension and diabetes mellitus with cerebral small-vessel disease infarct patterns. METHODS: Using a prospective stroke database, the 152 patients with computertomographic signs of small-vessel disease (lacunes and/or leucoaraiosis)--including as a subgroup of 85 cases with multiple lacunes and/or leucoaraiosis-were compared with 106 patients featuring pial artery infarcts. Statistical analyses of the rates of hypertension and diabetes included univariate tests (odds ratios) and a logistic regression model comprising the additional variables hypercholesterolemia, cigarette smoking, carotid stenosis, atrial fibrillation, and left cardiac thrombus. RESULTS: Multivariate testing revealed a significant association of hypertension and diabetes with multiple lacunar infarcts and/or leucoaraiosis (hypertension: odds ratio 2.0; 95% confidence interval 1.04-3.7; diabetes: odds ratio 1.9; 95% confidence interval 1.01-3.8), whereas for the total group of patients with small-vessel disease lesions no such effect was found. Among the other tested variables, only atrial fibrillation/left cardiac thrombus showed a significant negative association (odds ratio 0.5; 95% confidence interval 0.2-0.9) with lacunes/leucoaraiosis. CONCLUSION: Independent of other risk factors and other possible causes of stroke, both hypertension and diabetes appear to be strong determinants of multiple lacunar infarcts and/or leucoaraiosis.

Adult↗
PubMed1997

Microemboli on transcranial Doppler in patients with spontaneous carotid artery dissection.

High-intensity transient signals on transcranial Doppler sonography (TCD) are associated with atherosclerotic stenosis of the internal carotid artery. Few data exist regarding the detection of high-intensity transient signals in dissected carotid arteries. In the present study, 6 patients with spontaneous carotid dissection, defined by magnetic resonance techniques and duplex sonography, were examined by TCD. Both middle cerebral arteries were monitored simultaneously for 30 minutes. Four of the patients had ipsilateral cerebral ischemia, while 2 presented with other symptoms. High-intensity transient signals were detected in the middle cerebral artery ipsilateral to the dissection in 3 of the 4 patients with cerebral ischemia and in none of the patients with other presenting symptoms. No microemboli were found contralateral to the dissected arteries. Microemboli can be detected distally from dissected carotid arteries. The present findings support the assumption that embolism is a major cause of stroke in patients with carotid dissection, and suggest that high-intensity transient signals are more common among patients with cerebral ischemia secondary to dissection.

Adult↗
PubMed1997

Microemboli in patients with vertebrobasilar ischemia: association with vertebrobasilar and cardiac lesions.

BACKGROUND AND PURPOSE: Microembolic high-intensity transient signals (HITS) on transcranial Doppler ultrasound (TCD) are associated with carotid stenosis, artificial heart valves, and other cardiac conditions. Only one case report describes stroke-related HITS in the posterior cerebral circulation. This study was designed to assess prospectively the prevalence of asymptomatic microemboli in vertebrobasilar ischemia and to determine whether potential cardioembolic sources, vertebral or basilar occlusive disease, and infarct subtypes predict the detection of HITS. METHODS: We investigated 52 consecutive patients with acute or recent vertebrobasilar ischemia within 48 hours after admission. TCD monitoring was performed according to established criteria for 20 minutes on each posterior cerebral artery. Fetal origin of the posterior cerebral artery was an exclusion criterion and ruled out by carotid compression. RESULTS: Microembolic signals were detected in 10 patients (19.2%). In a multivariate logistic regression analysis that included all independent variables, potential cardiac sources were significantly associated with HITS (odds ratio [OR], 14.3; 95% confidence interval [CI], 1.6 to 128.4), in particular when more than one cardiac abnormality (OR, 32.7; CI, 4.1 to 259.3) or a high-risk source (OR, 14.0; 95% CI, 2.3 to 84.9) was found. Vertebrobasilar vessel lesions and infarct subtype were not related to the detection of microemboli. CONCLUSIONS: Cardiac sources of embolism are a determinant of HITS in posterior cerebral circulation ischemia, suggesting that cardioembolic infarcts in that territory might be more common than suspected. Vertebrobasilar vessel abnormalities are less likely to lodge microemboli, which may indicate histopathological changes different from carotid artery disease.

Aged↗