Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Noninvasive duplex scanning of carotid artery atherosclerotic plaque was performed in 286 consecutive patients referred to a cerebrovascular diagnostic laboratory. The presence and thickness of such plaque in the region of the carotid bifurcation were examined for association with the degree of vessel stenosis, age, sex, smoking history, history of prior transient ischemic attack or stroke, and systemic manifestations of atherosclerotic disease. Atherosclerotic plaque thickness was positively correlated with degree of vessel stenosis (P less than 0.0001). Both parameters were independent predictors of cerebrovascular events but plaque thickness was a better predictor of prior transient ischemic attacks (P less than 0.05), and vessel stenosis was a better predictor of prior stroke (P less than 0.005). Patient age (P less than 0.001) and pack-years of cigarette use (P less than 0.001) were independent positive predictors of carotid atherosclerotic plaque thickness. The greatest effect of smoking and atherosclerotic plaque thickness was seen in heavy smokers younger than age 55. Both carotid artery plaque thickness and pack-years of smoking were significant independent predictors of other systemic manifestations of atherosclerotic disease (P less than 0.05). Such noninvasive scanning of carotid artery atherosclerotic plaque demonstrates the significant role of age and smoking in the progression of disease. It also suggests a significant role for carotid atherosclerotic artery plaque in the pathophysiology of cerebrovascular events, especially transient ischemic attacks, even prior to the production of a flow-limiting stenosis. Finally, noninvasive screening of carotid artery plaque may provide a useful marker for the patient at risk for systemic atherosclerotic disease and identify the patient for whom maximal atherosclerotic risk factor modification is needed.
 ...
PMID:Thickness of carotid artery atherosclerotic plaque and ischemic risk. 223 25

Nonstenotic ulcerated atherosclerotic plaques of the carotid arteries may be associated with symptoms of transient ischemic attacks, amaurosis fugax, and stroke. Preoperative evaluation of patients with these symptoms has traditionally included ultrasound and arch aortography angiograms of the area of the carotid bifurcation. Recent evidence has shown that ultrasound is more accurate in detection and morphologic delineation of these nonstenotic lesions. We analyzed the hospital records of 21 patients with ultrasonographic evidence of disease in whom arteriograms were negative. The patient group comprised 15 men and six women, with an average of 66 years. All patients had symptoms of hemispheric transient ischemic attacks and were evaluated with B-mode ultrasound and arteriography. Ultrasound was positive and arteriogram "negative" in all of the patients (i.e., described by the radiologist as without hemodynamic significant disease or ulceration, or as normal). The ultrasound diagnosis was confirmed at operation with findings of 20 to 50 per cent stenosis and ulcerative plaques. At retrospective review of the arteriograms, three ulcerations were found in the 21 patients. We conclude that B-mode ultrasound better defines nonstenotic ulcerative lesions and decisions to perform carotid endarterectomy may be based on either positive test. An ulcerative plaque by B-mode ultrasound and appropriate symptoms, therefore, may not require angiography before operation.
 ...
PMID:Normal angiograms and carotid pathology. 224 Aug 70

From March 1980 to July 1988 a consecutive series of 256 patients (p.) underwent 301 carotid endarterectomy + patch with routine use of continuous intraoperative EEG monitoring and selective use of an intraluminal shunt (IS) for the presence of an atherosclerotic plaque concerning the internal carotid artery (ICA). Patients were divided in two groups: the first (42 p.) marked by contralateral ICA occlusion, the second (214 p.) without contralateral ICA occlusion (259 CEA). Immediate peroperative, long term and global (immediate and long term) outcomes were prospectively and comparatively studied. A temporary IS was inserted in 27 p. (64%) of the group I and in 38 p. (14%) of the group II. Immediate permanent postoperative neurological deficit occurred in 1 p. of group I (2.38%) and in 2 p. (0.9%) in group II. Immediate postoperative mortality was 0% and 0.9% in group I and II respectively. All p. had neurological valuation and Echo-Doppler of operated ICA and of the contralateral ICA every 6 months (middle follow-up 44 months). New neurological symptoms compared in 5.8% of p. of group I and in 5.23% of p. of group II with a stroke rate of 0% and 2.32% respectively. There were 2 restenosis of operated ICA, both of them in p. of group I, that underwent reoperation. In the two groups the principal causes of deaths were myocardial infarct and cancer; in the group I no death was due to stroke versus 1.86% in the group II.
 ...
PMID:[Carotid stenosis and obliteration of the contralateral carotid. A prospective study of the risks of a carotid endarterectomy intervention and its long-term results]. 224 48

Sudden fissuring of an atherosclerotic plaque has been suggested as the primary trigger of transient spontaneous ischemia in both the coronary and cerebral circulation. Measurements of urinary 11-dehydro-TXB2 and 2,3-dinor-TXB2, as well as results of Aspirin trials, have suggested that episodic platelet activation at the site of this acute vascular lesion is mediated, at least partly, by enhanced thromboxane (TX) A2 biosynthesis. Thus, episodic increases in metabolite excretion have been detected in unstable angina. Aspirin (75-325 mg/day) prevents about one third of all fatal and nonfatal thrombotic events in this setting. That a similar "dynamic" thrombotic process occurs during the early phase of acute myocardial infarction is suggested by thromboxane metabolite measurements and by the results of the ISIS-2 trial showing a similar impact of short-term Aspirin therapy to that seen in unstable angina. Percutaneous transluminal coronary angioplasty is associated with transiently enhanced TXA2 biosynthesis and Aspirin-suppressable periprocedural thrombotic complications. On the other hand, both non-insulin-dependent diabetes mellitus and type IIa hypercholesterolemia are associated with a relatively reproducible and persisting abnormality of TXA2-dependent platelet function. This association is likely to reflect a systemic rather than localized stimulus to platelet activation and a continuous rather than episodic alteration. Low-dose (50 mg/day) Aspirin can largely suppress thromboxane metabolite excretion in both diseases. Thus, low-dose Aspirin and/or selective prostaglandin H2/TXA2-receptor antagonists may be important tools to test the hypothesis that TXA2-dependent platelet activation represents an important transducer of the enhanced thrombotic risk associated with these metabolic abnormalities.
Stroke 1990 Dec
PMID:Thromboxane biosynthesis in cardiovascular diseases. 226 Jan 37

Free-floating clots of the extracranial internal carotid artery are generally considered as surgical emergencies. This retrospective study analyzes six free-floating clots diagnosed by arteriography. Three of these patients had a fixed stroke while the other three had an evolving stroke. Three patients had antecedent ocular or hemispheric transient ischemic attacks. The causes of free-floating clots in the internal carotid artery were atheromatous stenosis in two cases, ulcerated plaque in three cases, and carotid artery dissection in one. All six patients were seen late, approximately 15 hours after their neurologic accident. They were treated with intravenous heparin over a two to five week period. Repeat arteriograms demonstrated complete clot lysis in four instances, while partial lysis was seen in one case. Moderate extension of thrombus occurred in one case only. No further neurologic complications were noted during the treatment by heparin. As indicated by follow-up arteriographic findings, secondary surgery was performed for major carotid lesions and residual clots in five cases. The free-floating thrombus syndrome of the carotid artery should not be considered as a surgical emergency when discovered late in the wake of an acute neurologic accident.
 ...
PMID:Free-floating thrombus of the extracranial internal carotid artery. 226 24

In vitro studies have demonstrated that geometry of the carotid bifurcation predicts blood flow alterations associated with atherosclerotic plaque formation. We investigated intraindividual asymmetry of carotid atherosclerosis by measuring geometric aspects of the carotid bifurcation. We measured diameter stenosis, the internal carotid artery/common carotid artery area ratio, and the angle of the carotid bifurcation on 40 arteriograms. Stenosis asymmetry was significantly associated with area ratio asymmetry (r = 0.355, p less than 0.025); there was no such association between stenosis asymmetry and bifurcation angle asymmetry. Geometric factors of the carotid bifurcation, particularly the area ratio, may help explain intraindividual asymmetry in carotid atherosclerosis.
Stroke 1990 Feb
PMID:Geometric factors of the bifurcation in carotid atherogenesis. 230 2

We correlated the clinical and pathologic findings in 77 consecutive carotid plaques removed at endarterectomy to determine the clinical role of intraplaque hemorrhage. Intraplaque hemorrhages of various severity were seen in 86% of plaques. They were, for the most part, deeply located (63%) and infrequently connected with the lumen. They related closely to the severity of carotid stenosis, but bore no relationship to the timing of symptoms. Luminal thrombus was infrequently seen, and was always microscopic. Hemorrhage into carotid plaque appears to represent an index of the severity of the stenosis and plaque instability rather than to play a direct role in the pathogenesis of transient ischemic attacks or stroke.
 ...
PMID:Clinical significance of carotid plaque hemorrhage. 239 36

We conducted a prospective study of serial intravenous digital subtraction angiography to determine the relation of arterial disease risk factors and hemostatic variables with the presence of visible atheroma at the carotid bifurcation. Of the 492 patients with cerebrovascular disease or ischemic heart disease who entered the study, 354 had hematologic studies, including platelet aggregation in 230. Abnormal angiograms were associated with greater age, treated hypertension, current smoking, and lower hemoglobin levels but with higher uric acid, factor VIII, and fibrinogen concentrations. In patients presenting with isolated transient ischemic attacks, abnormal angiograms were also associated with higher levels of cholesterol and triglycerides. To study atheroma progression, the 230 patients with complete data at entry were recalled 2 years later. Repeat angiography in 209 patients showed progression of visible bifurcation disease in 13.4%. There was some evidence that progression was linked to higher age, hypertension, and more severe disease at entry, but further analysis was hampered by the small number of patients showing increased plaque size. The possible role of risk factors and hemostatic variables, especially fibrinogen, is discussed. Factors that did not correlate with progression of angiographically visible disease may also influence clinical end points by other mechanisms, such as thrombogenesis.
Stroke 1989 Nov
PMID:Arterial disease risk factors and angiographic evidence of atheroma of the carotid artery. 236 11

This paper reports the real time B-mode Doppler scanning findings of the extracranial portion of carotid arterial system (CAS) in 182 healthy persons (119 males and 63 females). The results showed that the diameter of the lumen of common carotid artery (CCA), bifurcation of common carotid artery (BCCA) and internal carotid artery (ICA) was larger in males than in females; there was no relationship between the diameter of the lumen of CCA, BCCA and ICA and body height; the diameter of lumen of CCA increased with age; 29 cases of atherosclerosis of the arterial wall (11 lesions with thickening of intima, 16 with hard plaque, one with soft plaque and 5 with stenosis) were observed; and the incidence of positive findings of atherosclerotic lesion of extracranial portion of CAS in the 40-49 age group and 50-59 age group was only 4.2% and 4.8% respectively, while the incidence in those aged over 60 increased markedly to 26.5-41.7%. These suggested that incidence of atherosclerosis in extracranial portion of CAS was not low in healthy persons without any evidence of stroke. As atheromatous lesions may be related to the consequent onset of stroke in the future, follow-up study and repeated Doppler scanning are necessary so as to observe the relationship between the location and severity of the lesion and the occurrence of cerebrovasculor disease. They may be helpful in determining the indication for carotid artery operation and also play a role in the prevention and treatment of CVD.
 ...
PMID:Study on atherosclerosis of extracranial portion of carotid artery system in healthy persons. 251 65

During the past 5 years it has been clearly established that there is a prominent morning increase in the frequency of onset of acute myocardial infarction. Similar increases have also been observed for the related conditions of sudden cardiac death, stroke and episodes of transient myocardial ischemia. The period from 6 a.m. to noon is also a time when a number of physiologic processes that could contribute to the onset of coronary thrombosis are intensified. Arterial pressure, which could lead to plaque rupture, rises; coronary tone increases; and platelet aggregability, which could contribute to a hypercoagulable state, increases. The immediate significance of these observations is the emphasis that should be placed on pharmacologic protection of patients during the morning hours. The primary longer-term significance of the recognition of the morning increase of onset of acute cardiovascular disease is the contribution it makes to the concept that onset of coronary thrombosis at any time of the day is frequently triggered by the activities of the patient. Investigation of this possibility may yield more information about the mechanism of disease onset and facilitate design of more effective preventive therapy.
 ...
PMID:Morning increase of onset of myocardial infarction. Implications concerning triggering events. 256 81


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>