Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Does the abandonment of hypothermic perfusion during cardiopulmonary bypass compromise cerebral protection and thus lead to a higher incidence of stroke? From 1987 to June 1993, 2,585 consecutive patients underwent myocardial revascularization using warm-body (perfusion at 37 degrees C), cold-heart (cold cardioplegic arrest) surgical technique and were followed for new overt neurologic deficits. Perfusion pressure was maintained between 50 and 70 mm Hg, and hematocrit was kept around 20%. There were 25 operative deaths (1%) in this normothermic group, and new neurologic deficits developed after operation in 25 patients (1%). These results were compared retrospectively with those in 1,605 patients who underwent myocardial revascularization between 1980 and 1986 with moderate hypothermic (25 degrees to 30 degrees C) perfusion, the same surgical team, and similar operative techniques. The normothermic group included more elderly patients, more patients with left ventricular dysfunction and unstable angina, and more frequent use of an internal mammary artery conduit. Neurologic complication rates were 1% and 1.3% for the normothermic and hypothermic perfusion groups, respectively. Risk factors for stroke that were identified included age greater than 70 years, severity of aortic arch atherosclerosis, and severe hypotension in the perioperative period. Thus, in a large clinical series, the incidence of overt neurologic injuries was found to be no higher with normothermic perfusion than with hypothermic perfusion.
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PMID:Stroke during coronary artery bypass grafting using hypothermic versus normothermic perfusion. 781 65

Recent studies have demonstrated that hypercholesterolemia is one of the major factor involved in the progression of coronary heart disease and that the reduction in plasma cholesterol reduces mortality for cardiovascular events. Indeed, recent experimental studies have demonstrated alterations in vascular reactivity in atherosclerosis. The aim of this study was to evaluate in patients with primary hypercholesterolemia the consequences of an effective of chronic treatment with inhibitor of HMG-CoA reductase on vascular responsiveness to cold pressure test. We observed a significant reduction in total plasma cholesterol during the study that was accompanied by a significant decrease in the response of peripheral vascular resistances to cold pressure test (55 +/- 4% vs 73 +/- 5% p < 0.01). There was also a significant relationship between the reduction of total cholesterol and the response of vascular resistance to the cold pressure test (r = 0.853, p < 0.05). Our results demonstrate that the reduction in total plasma cholesterol may influence the haemodynamic response induced by the activation of the sympathetic system.
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PMID:[The effects of plasma cholesterol reduction on vasoconstriction due to sympathetic activation in patients with moderate primary hypercholesterolemia]. 802 44

Does the use of warm-body perfusion in elderly patients with severe cerebrovascular disease lead to a higher incidence of stroke, due to hypotension secondary to low systemic vascular resistance? Two thousand, three hundred eighty-three (2,383) consecutive myocardial revascularizations were performed (1987-1992) using warm-body (perfusion 37 degrees C), cold-heart surgery (cold cardioplegic arrest). The perfusion pressure was maintained between 50-70 torr; hematocrit was kept around 20%. Prospective data during hospitalization revealed 23 operative deaths (1%), and 24 patients (1%) who developed new neurological signs after surgery. The latter formed three groups: Group I consisted of six patients with severe neurological deficits, who never regained consciousness and died after support systems withdrawal. Group II included 14 patients with postoperative clinical evidence of focal cerebral infarction (9 had hemiplegia, 2 had visual disturbance, and 3 showed alteration of memory), all of whom had residual defects at discharge; Group III was composed of four patients with minor neurological deficits after surgery (hemiparesis, gait disturbance, mental changes) which had cleared up by discharge. These data were compared retrospectively with 1605 patients (1980-1986) undergoing myocardial revascularization with moderate (25-30 degrees C) hypothermia and the same surgical team and operative techniques. Both groups had similar preoperative demographics except the warm group included more elderly patients, higher numbers with unstable angina and poor ejection fraction, and more frequent use of a mammary artery conduit. Neurological complications were 1% and 1.3% for the normothermic and hypothermic perfusion groups respectively. Incremental risk factors of stroke remain: age over 70 years, diffuse atherosclerosis of the aorta, carotid occlusive disease, and severe hypotension during perfusion.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Neurological complications during myocardial revascularization using warm-body, cold-heart surgery. 804 89

The regulation of flow and diameter of the coronary arteries depends on many factors. In normal subjects, increased coronary flow is associated with an increase in diameter of the epicardial coronary vessels. The coupling of these two independent variables depends on the integrity of endothelial function. In isolated arteries suppression of the endothelium induces an abnormal vasomotor response to acetylcholine. The presence of atherosclerotic lesions on the coronary vessels also induces the opposite response to the administration of acetylcholine, even in apparently normal segments. Other physiological coronary vasodilator stimuli, especially those which increase the concentration of noradrenaline, become vasoconstrictor in diseased coronary vessels. Finally, increasing coronary blood flow is not associated with increases in coronary diameter in patients with coronary atherosclerosis. This loss of flow-dependent vasodilatation is an early and diffuse phenomenon in subjects with cardiovascular risk factors. The authors have shown that this inversion of vasomotor responses observed by angiographic techniques, may also be documented by endocoronary ultrasonography. Their results demonstrate that the vasodilatation induced by papaverine or by the cold pressor test in 6 normal subjects is lost in 20 patients with coronary atherosclerosis and that the administration of Sin 1 induces a comparable vasodilatation in normal and diseased vessels. This study confirms that endothelial function is globally altered in atherosclerotic coronary artery disease.
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PMID:[Endothelial dysfunction and coronary vasomotricity. Contribution of endocoronary echography]. 828 21

This study was performed to evaluate the accuracy of intravascular ultrasound for the assessment of coronary artery vasomotion and endothelial function in patients with atherosclerosis. Twenty patients with luminal irregularities on the coronary angiogram and a high cholesterol level (287 +/- 19 mg/dl) (group 1) and six patients with angiographically smooth arteries and a minimally elevated cholesterol level (197 +/- 12 mg/dl) (group 2) were studied. A mechanical intravascular ultrasound probe (4.3F) was placed into the proximal segment of the coronary artery. The ultrasound images were recorded on super VHS videotape and were then digitized allowing the measurement of the lumen area and then the calculation of a mean intimal thickness index. Endothelial function was studied during sympathetic stimulation by a cold pressor test and, after increasing coronary blood flow, by intracoronary papaverine administration; a 1 mg bolus of linsidomine was then administered into the coronary artery. Patients in group 1 had a higher mean intimal thickness (1.52 +/- 0.64 mm) than those in group 2 (0.18 +/- 0.08 mm) (p < 0.001). In response to sympathetic stimulation, a vasoconstricting effect occurred in group 1 (9.5 +/- 1.3 mm2 vs 11.4 +/- 1.2 mm2 at baseline, p < 0.05), while a vasodilating action was observed in the control group (11.6 +/- 2.1 mm2 vs 10.4 +/- 1.8 mm2 at baseline, p < 0.05). After papaverine infusion, a trend toward a vasoconstricting effect was observed in response to increased flow in group 1 (10 +/- 1.3 mm2 vs 11.4 +/- 1.2 mm2 at baseline, p < 0.05). that was not observed in group 2 (9.4 +/- 2 mm2 vs 8.9 +/- 1.9 mm2, p = NS). Linsidomine infusion induced a significant vasodilating effect in both groups (p < 0.001). In conclusion, intravascular ultrasound may be considered a useful tool to assess endothelial function of large coronary arteries and to obtain the precise relationship between wall thickness and the vasomotor response.
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PMID:Assessment of coronary vasomotion by intracoronary ultrasound. 832 94

Raynaud's syndrome manifests as a progressive color change of the fingers in response to cold, vibration or stress; the digits first turn white, then blue and finally red. The condition is called Raynaud's disease when it is a benign, primary condition. When it is secondary to another disease, such as lupus, scleroderma or atherosclerosis, it is termed Raynaud's phenomenon. Laboratory tests, i.e., complete blood count, chemistry screen, antinuclear antibody, lupus erythematous test and rheumatoid factor, should be used to seek underlying diseases before the symptoms are manifest. Other tests should be selected as indicated by the history and physical. There are many adjustments in lifestyle and working conditions that the patient can use to minimize the symptoms of Raynaud's syndrome. The primary care provider has an important role in teaching patients to protect their hands from the effects of cold, stress, nicotine and vibration. Adaptive devices and protective clothing minimize the symptoms of Raynaud's syndrome.
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PMID:The diagnostic puzzle and management challenge of Raynaud's syndrome. 845 39

Abnormal vasoreactions of peripheral arteries to cold stimulus of both hands were studied in controls and NIDDM patients by measuring changes of toe skin temperatures using thermography, and compared with thickness and calcification of wall and inner diameters of popliteal and dorsal pedal arteries using B mode ultrasonic imaging. Cold stimulated vasoreactions were divided into four patterns: (1) normal type (skin temperature going up and down within 1 degree C on the basal line), (2) increasing type (temperature going up), (3) decreasing type (temperature going down) and (4) flat type (no change of temperature). The difference in patterns was suggested to be related to the degree of atherosclerotic changes of the dorsal pedal artery obtained from the ultrasonic studies. The mechanism of abnormal vasoreactions of arteries with atherosclerosis is not clear, but cold stimulated thermography may be a useful tool in evaluating the state of peripheral atherosclerosis.
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PMID:Abnormal vasoreaction of peripheral arteries to cold stimulus of both hands in diabetics. 880 82

A method is described for the large scale preparation of reconstituted high density lipoproteins (rHDL) suitable for therapeutic use. Apolipoprotein A-I (apoA-I was isolated from precipitates obtained by cold ethanol fractionation of human plasma. This process includes several steps for virus removal and virus inactivation, among them pasteurization. Reconstitution of lipoprotein particles was performed by cholate dialysis using soybean phosphatidylcholine as the lipid source. An apoA-I:lipid ratio of 1:150 (mol:mol) was obtained. Redissolved rHDLs were disc-shaped particles resembling nascent HDL, as assessed by electron microscopy. The method was optimized for low content of free apoA-I protein as well as the low concentration of free lipid. The product was stabilized by lyophilization in the presence of sucrose. In vitro studies show potential effects it the prevention of gram-negative septic shock and in the inhibition of atherosclerosis.
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PMID:Production and characterization of a reconstituted high density lipoprotein for therapeutic applications. 891 58

Nitrotyrosine in human and animal tissues has been associated with pathologic conditions such as atherosclerosis, renal failure, and acute lung disease. In this study, free and protein-associated nitrotyrosine were determined in plasma and tissue samples using a dual-channel electrochemical detection method. Free nitrotyrosine was quantified in acetonitrile-extracted samples while protein-associated nitrotyrosine was determined in proteinase K-digested samples. In human plasma, total nitrotyrosine increased from 2.3 to 4.3 and 13.2 mumol/mol Tyr following addition of 0, 0.5, and 1 mM ONOO-. To determine if nitrotyrosine was produced during ex vivo hypothermic preservation, rat livers were stored in University of Wisconsin solution (UW) for 0, 6, or 8 h and reperfused for 3 h. Total nitro-tyrosine increased 359 and 908% after 6 and 8 h preservation compared to 0 h. To determine if nitrotyrosine was produced in vivo following hepatic ischemia, a rat preservation-transplantation model was utilized in which livers were flushed with cold UW (0-h group) or transplanted following 6 h hypothermic preservation in UW. Free nitrotyrosine increased from 15.7 +/- 0.3 in the 0-h group to 23.6 +/- 2.5 mumol/mol Tyr, 24 h posttransplant of 6-h preserved livers. Protein-associated nitrotyrosine increased from 9.5 +/- 1.1 in the 0-h group to 27.5 +/- 0.7 mumol/mol Tyr in the 6-h preservation-transplantation group. Protein-associated nitrotyrosine provides an integrative determination of nitration. Detection of free and protein-associated nitrotyrosine in biologic samples may allow insight into the role of .NO-derived oxidants in tissue injury associated with various pathologic conditions.
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PMID:Free and protein-associated nitrotyrosine formation following rat liver preservation and transplantation. 918 89

We describe an unusual case of acute myocardial infarction due to vasospasm in a 13-year-old boy. He was admitted to our hospital with severe congestive heart failure and shock. He had experienced a feeling of chest oppression with dyspnea while running, which grew worse. He then lost consciousness and was brought by ambulance to our intensive care unit. He had had similar but milder episodes of chest oppression months earlier. The family history revealed that his father had died suddenly from hypertrophic cardiomyopathy and that his grandmother also had hypertrophic cardiomyopathy. On admission, the patient was bathed in a cold sweat, his pulse was weak, and his blood pressure was too low to measure. Coarse crackling and wheezing were audible in both lung fields. Administration of catecholamine and intra-aortic balloon pumping failed to stabilize the hemodynamic variables, but percutaneous cardiopulmonary support proved to be lifesaving. Coronary arteriography performed during his convalescence showed on evidence of atherosclerosis. The acetylcholine provocation test ultimately revealed a diagnosis of acute myocardial infarction due to vasospasm.
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PMID:Acute myocardial infarction due to vasospasm in a 13-year-old-boy. 922 1


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