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H Mast

Publications and source records attributed to H Mast.

At least 55 records · Page 3Linked to original sources
PubMed1996

[Diagnostic advantage by transthoracic and transesophageal echocardiography in acute ischemic infarct. A contribution to indications for transesophageal echocardiography].

The yield of TTE and TEE in identifying cardiac sources of embolism in patients with TIA or stroke was calculated from data from the Berlin Stroke Data Bank. High risk sources of embolism were detected by TTE in 4.2% with and in 1.6% of patients without evidence of cardiac disease from case history, clinical symptomatology, and ECG respectively. TEE yielded high risk sources of embolism in 10.6% of patients with and in 4.2% of patients without evidence of cardiac disease from case history, clinical symptomatology, ECG, and TTE respectively. Pathological findings were 12 atrial thrombi, 4 ventricular thrombi, and 1 atrial myxoma. 12 out of 14 atrial thrombi were only detected by TEE and not by TTE. There was a significant association of high risk cardiac sources of embolism with pial artery infarct pattern in CCT compared with lacunes. The yield of TEE in detecting high risk sources was not significantly associated with CCT infarct pattern probably due to the small numbers of investigations.

Adult↗
PubMed1996

"Semantic" conduction aphasia from a posterior insular cortex infarction.

A unique infarction limited to the posterior insula and intrasylvian parietal opercular cortex produced a subtype of conduction aphasia, characterized by a predominance of semantic paraphasias. Temporal lobe hypoperfusion seen on hexamethylpropyleneamineoxime single-photon emission computed tomography in the absence of any signs of ischemia suggested that cortical diaschisis played a role in the emergence of this syndrome.

Aphasia, Conduction↗
PubMed1996

[Potential embolism sources in transesophageal echocardiography--prognostic value in patients with cerebral ischemia].

To determine whether potential sources of embolism such as atrial septal aneurysm (ASA), patent foramen ovale (PFO), mitral valve prolapse and atherosclerotic aortic debris can influence the outcome of patients after first cerebral ischemic event (CIE), 214 patients (124 stroke, 21 RIND, 69 TIA) were examined by transesophageal echocardiography (TEE) up to 3 weeks after CIE and followed up for 12 months. For risk estimation, the patients were subdivided into group I = without and group II = with potential sources of embolism. We additionally took into account cardiovascular diseases and atherosclerotic risk factors (group la + IIa without, Ib + IIb with). Recurrence occurred in 14 out of 214 patients (6.5%). Univariate analysis demonstrated that the presence of ASA, PFO and aortic debris as well as cardiovascular diseases and atherosclerotic risk factors was associated with a twofold to threefold higher incidence of recurrent events. While potential sources of embolism alone had no influence on the recurrence rate (group I:8/111 = 7.2% versus group II: 6/103 = 5.8%, n.s.), this was significantly different in relation to cardiovascular diseases and atherosclerotic risk factors (groups Ia + IIa: 0/66 = 0%, groups Ib + IIb: 14/148 = 9.8%, p < 0.01). Our results show that potential sources of embolism do not appear to influence the recurrence rate in cardiac healthy subjects. In patients with cardiovascular diseases, however, potential sources of embolism are associated with a higher risk of recurrence, and should therefore be imaged by TEE.

Adult↗
PubMed1996

[Indications for endarterectomy in asymptomatic stenoses of the internal or common carotid artery--results of the North American ACAS Study].

OBJECTIVE: To determine the effect of endarterectomy on the primary prevention of ischemic stroke in patients with asymptomatic carotid artery stenosis. METHODS: In a prospective, randomized, multicenter trial 1659 patients with asymptomatic carotid stenosis of 60% or more were studied in two treatment arms (endarterectomy: n = 825; medical therapy: n = 834). Endpoints were: (1) ischemic stroke in the vascular territory of the study artery, (2) any perioperative stroke or any perioperative death. RESULTS: The Kaplan-Meier 5-year-risk estimation showed a relative risk reduction of 53% (confidence interval: 22%-72%) for patients in the surgical arm. The combined perioperative morbidity and mortality rate was 2.3%. CONCLUSION: Endarterectomy of asymptomatic carotid artery stenosis performed with a perioperative complication rate of less than 3% reduces the 5-year risk of ipsilateral stroke.

Adult↗
PubMed1995

Central pontine myelinolysis: clinical syndrome with normal serum sodium.

Central pontine myelinolysis (CPM) is a rare syndrome generally linked to hyponatremia. Autopsy and imaging studies described demyelination in the central pons, in some cases combined with thalamic, internal capsular, hemispheric and cerebellar white matter lesions. The clinical syndrome and prognosis spans from asymptomatic patients displaying only imaging lesions to coma and death. Frequent findings are pyramidal tract and pseudobulbar signs. No effective treatment is known. Alcohol abuse is often associated. The imaging pattern of CPM is unique and generally accepted as diagnostic when other causes such as ischemia, multiple sclerosis, tumors, radiation, or pharmacological effects are ruled out. However, the exact mechanism of this selective process of demyelination remains obscure. The current major controversy concerns the role of therapeutic efforts of sodium level restoration in the etiology of CPM. We present a case of CPM where no hyponatremia was found. We hypothesize that (1) iatrogenic sodium restoration may not in all cases of CPM be the putative mechanism, (2) the clinical onset of CPM may in some patients represent a delayed response to an initially asymptomatic demyelination, and (3) normal admission sodium levels do not exclude the diagnosis of CPM.

Humans↗
PubMed1995

Hypertension and diabetes mellitus as determinants of multiple lacunar infarcts.

BACKGROUND AND PURPOSE: We investigated the relationship between hypertension, diabetes mellitus, and lacunes. METHODS: From 1237 cases of ischemic stroke in the Stroke Data Bank of the National Institute of Neurological and Communicative Disorders and Stroke, data from 637 patients whose initial computed tomogram showed lacunar (n = 184) or nonlacunar infarcts (n = 453) were analyzed. The group with lacunar infarcts was further divided into subgroups according to whether the patients had multiple (n = 40) or single (n = 144) lacunar infarcts. The association of hypertension and diabetes mellitus with lacunar infarcts was investigated using logistic regression models that included age, sex, and cardiac disease. Similar models were used to analyze the effects of diastolic and systolic blood pressure. RESULTS: Hypertension (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.1 to 6.0) and diabetes (OR, 2.3; 95% CI, 1.1 to 4.5) were significantly related to multiple but not to single lacunes. Cardiac disease was inversely associated with both single and multiple lacunes. Diastolic blood pressure significantly affected the probability of multiple lacunar infarcts (OR, 1.4; 95% CI, 1.04 to 1.9), whereas systolic pressure did not. CONCLUSIONS: There may be etiologically distinct lacunar infarct subgroups, with multiple lacunes being strongly related to hypertension and diabetes mellitus. Other stroke risk factors may be more important in patients with single lacunes. Diastolic rather than systolic pressure seems to be a major determinant of multiple lacunes.

Adult↗
PubMed1995

Transcranial Doppler ultrasonography in cerebral arteriovenous malformations. Diagnostic sensitivity and association of flow velocity with spontaneous hemorrhage and focal neurological deficit.

BACKGROUND AND PURPOSE: We sought to investigate (1) the sensitivity of transcranial Doppler ultrasonography (TCD) for diagnosis of cerebral arteriovenous malformations (AVMs) and (2) the association of feeding artery flow velocity profiles with spontaneous hemorrhage and focal neurological deficit in AVM patients. METHODS: We examined 114 consecutive AVM patients prospectively by TCD; 22 non-AVM patients with acute cerebral hemorrhage and 52 normal subjects served as controls. To estimate the association of blood flow velocity patterns in feeding arteries with spontaneous hemorrhage and focal neurological deficit, the total group of AVM subjects was divided into patients with and without a history of bleeding and also into those with and without clinical signs of "steal" (focal deficit unrelated to hemorrhage). RESULTS: Sensitivity for large and medium-sized AVMs was high (> 80%), whereas 62% of small AVMs were missed. TCD was also highly sensitive (80%) in a group of five AVM patients with acute hemorrhage. Flow velocity profiles were not related to spontaneous hemorrhage (mean velocity, 111 cm/s in patients with hemorrhage versus 114 cm/s in patients without hemorrhage; P = .65) or clinical signs of steal (mean velocity, 111 cm/s versus 113 cm/s in patients with and without steal, respectively; P = .89). CONCLUSIONS: We concluded that (1) TCD is highly sensitive for large and medium-sized AVMs; (2) in acute cerebral hemorrhage TCD may help to differentiate AVM from non-AVM bleeds; (3) the predictive value of TCD findings for clinical sequelae of AVMs remains undetermined; and (4) the concept of hemodynamic steal in AVMs is not supported by TCD data.

Adult↗
PubMed1995

'Steal' is an unestablished mechanism for the clinical presentation of cerebral arteriovenous malformations.

BACKGROUND AND PURPOSE: Focal neurological deficits (FNDs) in patients with arteriovenous malformations (AVMs) have been widely attributed to the phenomenon of "cerebral steal." The incidence of focal deficits was investigated in a large prospective sample. METHODS: Using data from patient history and examination, CT or MRI, and transcranial Doppler sonography, we studied 152 consecutive, prospective AVM patients for evidence of FNDs unrelated to a hemorrhagic event. Feeding mean arterial pressure was measured during superselective angiography. RESULTS: Two (1.3%) of 152 patients met the criteria for a progressive FND. Nonprogressive FNDs were seen in 11 (7.2%) patients (stable in 4.6%, reversible in 2.6%). The median observation time period was 17 months (range, 1 to 60 months). There were no differences in transcranial Doppler mean velocities in feeding arteries in FND versus non-FND groups (118 +/- 44 versus 112 +/- 37 cm/s, P > .05) or pulsatility indexes (0.53 +/- 0.20 versus 0.55 +/- 0.15, P > .05). Feeding artery pressure was similar in FND (n = 10) and non-FND (n = 96) groups (39 +/- 16 versus 39 +/- 16 mm Hg at a systemic pressure of 82 +/- 18 versus 75 +/- 14 mm Hg, NS). CONCLUSIONS: Nonhemorrhagic focal neurological syndromes in AVM patients are infrequent. Progressive deficits are especially rare. There was no relation between feeding artery pressure or flow velocities and FND. There does not appear to be sufficient evidence to assign steal as an operative pathophysiological mechanism in the vast majority of AVM patients.

Adult↗
PubMed1995

Superior vena cava syndrome: current concepts of management.

Superior vena cava syndrome usually results from extraluminal compression by tumor or intraluminal thrombosis due to an indwelling catheter. Percutaneous interventional techniques and thrombolysis allow for immediate relief of symptoms with low recurrence rates.

Carcinoma, Small Cell↗
PubMed1995

Outcome analysis of preoperative embolization with N-butyl cyanoacrylate in cerebral arteriovenous malformations.

PURPOSE: To determine the influence of preoperative N-butyl cyanoacrylate embolization on outcome in the treatment of cerebral arteriovenous malformations. METHODS: Two groups were compared: 30 patients who underwent surgery and embolization versus 41 patients who underwent surgery only. Both groups were categorized by Spetzler-Martin grade and evaluated with the Glasgow Outcome Scale at various intervals. The long-term follow-up in months was, for surgery only, mean of 35 and range of 4 to 59, and for surgery and embolization, mean of 10 and range of 1 to 19). RESULTS: The arteriovenous malformations in the surgery and embolization group had a larger average greatest diameter (4.2 +/- 1.5 cm versus 3.4 +/- 1.8 cm) and were of higher Spetzler-Martin grade (89% versus 68% grade III-V). No significant difference in the preoperative or immediate postoperative (less than 24 hours) Glasgow Outcome Scale was identified between the two groups. At I week after surgery, the surgery and embolization group displayed a significantly better outcome evaluation (70% versus 41% with Glasgow Outcome Scale score of 5). The long-term evaluation continued to favor the surgery and embolization patients (86% versus 66% with Glasgow Outcome Scale score of 5). CONCLUSION: Preoperative N-butyl cyanoacrylate embolization improves postsurgical outcome.

Adult↗
PubMed1994

Cardioembolic stroke: results from three current stroke data banks.

About 17% of all transient ischemic attacks (TIA) and ischemic strokes were due to cardiogenic embolism in three prospective stroke registries (Berlin, Giessen, Klosterneuburg). Most of these patients can be identified by history, clinical examination, conventional ECG, and appropriate use of echocardiography. Widespread screening of stroke patients with transesophageal echocardiography, as intented in the protocol of two registries, did not appreciably increase the portion of patients with the final diagnosis of cardiogenic embolism, although, in many cases, minor-risk embolic sources can be identified. Prognosis for death or early recurrence after cardiogenic brain embolism was not worse than assumed previously.

Adult↗
PubMed1994

Cardiac sources of embolism in patients with pial artery infarcts and lacunar lesions.

BACKGROUND AND PURPOSE: On the assumption that the majority of lacunes are caused by small-vessel diseases and that pial artery infarcts arise from cardio-embolic or large-vessel diseases, 194 patients from the Berlin Cerebral Ischemia Data Bank with either lacunar or pial artery infarcts were analyzed for the frequency of cardiac sources of embolism. The primary hypothesis was that the frequency of cardiac sources of embolism is higher among pial artery infarct subjects. METHODS: The presence of cardiac sources of embolism was estimated by electrocardiographic and transthoracic and transesophageal echocardiographic studies. Cranial computed tomography scans were evaluated by two masked observers. RESULTS: The overall rate of cardiac sources of embolism did not differ significantly between the lacunar and the pial artery infarct group (66% versus 71%; odds ratio, 0.80; confidence interval, 0.43 to 1.50). Echocardiographic evidence of cardiac thrombi was positively associated with pial artery infarcts (odds ratio, 0.18; confidence interval, 0.04 to 0.80); atrial fibrillation and all other cardiac sources were not. CONCLUSIONS: Left cardiac thrombi are significantly associated with pial artery infarcts. Other presumed cardiac sources of embolism, including atrial fibrillation, may often represent coincidental findings or have a less strong tendency to result in pial artery infarcts.

Adolescent↗
PubMed1994

The influence of hemodynamic and anatomic factors on hemorrhage from cerebral arteriovenous malformations.

The physiological and anatomical aberrations that result in hemorrhage from cerebral arteriovenous malformations (AVMs) remain unclear. In an attempt to clarify which conditions may predispose to hemorrhage, we examined clinical and physiological indices on presentation groups of either hemorrhage or nonhemorrhage in a large cohort of patients (n = 449). Variables examined included AVM size, type of venous drainage, transcranial Doppler (TCD) velocities, feeding mean arterial pressure (FMAP), and draining vein pressure. TCD and pressure data were obtained before any treatment. Age (mean +/- standard deviation) at the time of presentation was 33 +/- 13 years and did not differ between groups. Patients with small (< or = 2.5 cm) AVMs presented more frequently with hemorrhage (90%) than did patients with medium (> 2.5 and < or = 5.0 cm; 52%) or large (> 5.0 cm; 50%) AVMs (P = 0.0001). The 48 of 94 AVMs (51%) with deep venous drainage were more likely to have hemorrhage (P = 0.0219) than were those with superficial drainage (24 of 73 [33%]). Deep drainage was a predictor of hemorrhage even in the subgroup of medium and large supratentorial AVMs (P = 0.005). There was no difference in draining vein pressure (n = 18) between groups (21 +/- 10 and 19 +/- 11 mm Hg, respectively; P = 0.7812). FMAP (n = 52) was higher in the hemorrhage than in the nonhemorrhage group (44 +/- 13 versus 34 +/- 10 mm Hg; P = 0.0007) but was only weakly related to the size of the lesion (largest dimension) (y = -0.74x + 40; r = 0.09).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Lacunar brain infarct in carotid occlusion].

The etiology of lacunar CCT lesions is controversial. We report a patient with recurrent ischemia in the territory of the right internal carotid artery. CCT initially showed a fresh non-lacunar lesion in the area of the basal ganglia and internal capsule. Subsequently, repeat CCT revealed a singular lacunar defect in the internal capsule. The Doppler sonographic investigations showed an internal carotid artery occlusion. This case supports the hypothesis that an embolic or hemodynamic etiology of the lacunae is possible.

Aged↗
PubMed1993

Cerebral ischemia induced by compression tests during transcranial Doppler sonography.

Compression tests performed during transcranial Doppler sonography are intended for support in identifying vessels and measuring collateral circulation within the circle of Willis. The resulting information is thought to be valuable in patients with extracranial carotid stenoses, especially for planning carotid and extra-/intracranial bypass surgery. In a retrospective analysis of a series of 380 cases, two patients with symptomatic carotid artery stenoses suffered three compression-induced focal cerebral ischemias. In two instances, these ischemias started under compression. The resulting deficits were reversible. One patient developed an additional and persisting motor deficit whose onset was delayed. The diagnostic benefit of compression tests is not established nor its risk well defined. They should not be used routinely.

Aged↗