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)

A 48-year-old black man had his first attack of chest pain on exertion, radiating to both arms, in December 1982 (angina pectoris). It was undoubtedly preceded by a period of asymptomatic coronary atherosclerosis of unknown duration. The first anginal attack was followed by three to four similar episodes over the next four months. The attacks became more prolonged, frequent, and severe thereafter (so-called "pre-infarct" angina), and six days later the patient showed signs of having developed actual myocardial necrosis. The patient underwent saphenous vein coronary artery bypass surgery but could not be weaned from the pump. He died late on the day of surgery. He was found at autopsy to have severe old three-vessel coronary artery disease with the myocardial changes that would be expected from the severe global ischemia to which this heart was undoubtedly subjected. Several basic and important differences between this sort of a circumferential subendocardial infarct and a transmural infarct are discussed, as is the basis for the striking subendocardial hemorrhage.
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PMID:Acute circumferential subendocardial infarction. 162 59

The aim of this study was to determine the significance of the "coronary factor" in patients with essential hypertension (EH). Electrocardiogram Holter monitoring was performed in 61 patients with EH stage II (according to the World Health Organization criteria). Silent, ie, painless ST-segment depression, was found in 34 patients on whom echocardiography, a treadmill test, and transesophageal pacing were performed. In 21 patients with EH and silent ischemia, the examination included 201Tl stress scintigraphy, coronary angiography, and a platelet aggregation test. In 15 patients, catecholamines and beta-endorphins were obtained in blood samples during silent ischemia. 201Tl scintigraphy showed transient defects of perfusion without clearance abnormalities (group I) and with clearance abnormalities (group II). The patients in group I had more severe left ventricular hypertrophy (LVH) and a significantly higher platelet aggregation response to 0.5 mumol/L adenosine diphosphate; one patient in this group had coronary atherosclerosis. LVH and the platelet aggregation response was less pronounced in the patients in group II, but atherosclerotic lesions of a coronary artery were observed in four patients. In both groups, norepinephrine and beta-endorphin levels were increased during silent episodes of ischemia. The results suggest that there are different pathogenetic mechanisms of coronary insufficiency in patients with EH, a hypertensive heart, and silent ischemia.
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PMID:Silent myocardial ischemia in patients with essential hypertension. 163 37

The normal control of coronary blood flow is through alterations in the resistance of the intramyocardial arterioles (R2). Myocardial cellular hypoxia causes increased breakdown of ATP (or decreases synthesis) resulting in increased concentrations of the purine metabolite, adenosine. This potent endogenous, vascular smooth muscle relaxant vasodilates the R2 arterioles increasing coronary blood flow and myocardial O2 delivery. This mechanism autoregulates coronary blood flow according to myocardial O2 needs. Myocardial hypertrophy (from chronic hypertension) or coronary atherosclerosis interfere with this process and result in myocardial ischemia which may cause symptoms (angina), signs (ECG changes, regional muscle dysfunction) or tissue death (myocardial infarction). In addition, coronary atheroma disrupt endothelial function in the large R1 coronary arteries predisposing to vasoconstriction, platelet aggregation and thrombosis. Therapeutic measures for controlling ischemia may include decreasing oxygen demand (especially heart rate) and maintaining supply (R1 vasodilators and anti-thrombotic drugs such as non-steroidal anti-inflammatories). Intravenous, most inhalational and regional anesthesia appear to interfere minimally in the control of both the normal and ischemic coronary circulation. Thus optimizing myocardial oxygen balance (maintaining supply and decreasing demand) during anesthesia protects the ischemic myocardium. High doses of isoflurane, sevoflurane or desflurane are potent R2 coronary vasodilators which may cause redistribution of collateral blood flow away from ischemic regions (coronary steal). However, if tachycardia and hypotension are avoided, such an effect has not been shown experimentally or clinically. Preliminary evidence suggests that halothane may preferentially dilate R1 arteries and/or interfere with platelet aggregation. If these effects are confirmed, then halothane may prove to be the anesthetic of choice in the non-failing ischemic heart.
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PMID:Physiology, pathophysiology and pharmacology of the coronary circulation with particular emphasis on anesthetics. 164 43

1. Nilvadipine (FK 235, FR 34235) suppressed ischemia (20 min)-reflow (20 min)-induced paw edema of mice (ED30:0.4 mg/kg i.v. and 2 mg/kg p.o.). Other calcium entry blockers of dihydropyridine-type also suppressed the edema, but 30-fold higher doses were required. 2. Oral dosing of nilvadipine suppressed carrageenan-induced paw edema (ED30:15 mg/kg in rats and 20 mg/kg in mice) at a potency corresponding to that of an anti-inflammatory drug, ibuprofen. Nifedipine, nicardipine and nimodipine resulted in a suppression of 30% only with 100 mg/kg oral dosing in rats. Nitrendipine, diltiazem and verapamil were without effect. 3. Nilvadipine inhibited superoxide radical (O-2production from xanthine oxidase (XOD) both with lactate dehydrogenase + NADH method and cytochrome c method (IC50:90 and 100 micrograms/ml, respectively). Nifedipine and nicardipine showed some inhibition, but the other calcium entry blockers failed to inhibit significantly even at 320 micrograms/ml. As uric acid formation was not reduced by the tested drugs, the inhibitory action might be due to their O-2scavenging effects. 4. Superoxide production of neutrophils from casein-induced peritoneal fluid in rats was most strongly inhibited by nilvadipine when the cells were stimulated by a calcium ionophore, A23187 (IC50:4 micrograms/ml). Inhibition by this drug when stimulated by f-methonyl-leucyl-phenylalanine and phorbol myristate acetate was less effective (IC50:20 and 30 micrograms/ml, respectively). Nifedipine and nicardipine inhibited neutrophil O-2production at higher concentrations (30-200 micrograms/ml) with all stimulants. Inhibitory actions by other drugs were weak. 5. Triggering of atherosclerosis depends largely on the oxidative stress on blood vessels after recently established concept.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Inhibition by nilvadipine of ischemic and carrageenan paw edema as well as of superoxide radical production from neutrophils and xanthine oxidase. 165 7

Intra-arterial infusions used in treatment of ischemia of lower extremities in patients with obliterating atherosclerosis can cause pronounced vasoconstrictory reactions in distal parts of the extremity with reduced pulse blood filling and oxygenation of tissues. As necessary measures of prophylactics of negative shifts in regional blood circulation the author suggests to be valuable anesthesia and atraumatic character of interventions, use of warm solutions, exclusion of irritating drugs and osmotically active substances. The final efficiency of intra-arterial infusions is dependent on the observation of the above conditions.
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PMID:[An evaluation of the results of intra-arterial injections in treating chronic ischemia of the lower extremities]. 166 30

Discriminative mathematical function was used for the classification of patients with atherosclerosis in the lower limbs. Considering 8 features of the blood supply to the lower limbs, 500 patients selected from the Polish centres of vascular surgery were classified according to the degree of ischemia. This mathematical analysis and classification proved to be comparable with clinical assessment. Described method is an example of the use of the mathematic tool which is particularly useful in the analysis of large groups of patients.
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PMID:[Test for evaluating diagnostic discriminative function for assessment of blood supply to the lower limbs in patients with atherosclerosis]. 166 32

The Cardiovascular Health Study (CHS) is a population-based, longitudinal study of coronary heart disease and stroke in adults aged 65 years and older. The main objective of the study is to identify factors related to the onset and course of coronary heart disease and stroke. CHS is designed to determine the importance of conventional cardiovascular disease (CVD) risk factors in older adults, and to identify new risk factors in this age group, especially those that may be protective and modifiable. The study design called for enrollment of 1250 men and women in each of four communities: Forsyth County, North Carolina; Sacramento County, California; Washington County, Maryland; and Pittsburgh, Pennsylvania. Eligible participants were sampled from Medicare eligibility lists in each area. Extensive physical and laboratory evaluations were performed at baseline to identify the presence and severity of CVD risk factors such as hypertension, hypercholesterolemia and glucose intolerance; subclinical disease such as carotid artery atherosclerosis, left ventricular enlargement, and transient ischemia; and clinically overt CVD. These examinations in CHS permit evaluation of CVD risk factors in older adults, particularly in groups previously under-represented in epidemiologic studies, such as women and the very old. The first of two examination cycles began in June 1989. A second comprehensive examination will be repeated three years later. Periodic interim contacts are scheduled to ascertain and verify the incidence of CVD events, the frequency of recurrent events, and the sequellae of CVD.
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PMID:The Cardiovascular Health Study: design and rationale. 166 7

Platelet activation releases not only thromboxane A2 but also serotonin, another vasoconstrictor agent that acts on blood vessels through a specific, 5-HT2 receptor. The development of ketanserin, the selective 5-HT2-receptor blocker, has made it possible to explore the role of serotonin in animal models and patients with endothelial injury and atherosclerotic disease. In animals models, growing collateral arterial vessels are exquisitely sensitive to the vasoconstrictor effects of serotonin, which are reversed by ketanserin. When endogenous platelet activation is induced by endothelial injury, a combination of ketanserin and a thromboxane synthesis inhibitor or antagonist is more effective at reversing collateral arterial vasoconstriction than either agent alone. More recently, studies at the time of angiography in humans with advanced atherosclerosis have shown that more than 50% display a dilator response to ketanserin in low doses: the response primarily involves dilatation of collateral arterial vessels, which is associated with a significant increase in calf blood flow. These findings support existing evidence that platelet products contribute to the ischemia syndromes due to atherosclerosis, and provide a promising approach to improved management.
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PMID:Implications of thrombosis and vasospasm in peripheral vascular disease. 171 69

We have previously shown the safety and efficacy of University of Wisconsin solution for hypothermic preservation of the human donor heart in a pilot group of 16 transplant recipients. The present study is a randomized clinical trial comparing University of Wisconsin solution to conventional preservation using crystalloid cardioplegia and saline storage within a 4-hour limit of ischemia. Heart transplant recipients (n = 42) were randomized into two groups: those receiving hearts preserved by University of Wisconsin solution, the UWS group (n = 22), and those receiving hearts preserved in the conventional manner, the CCS group (n = 20). Recipient age, gender, heart disease, and preoperative inotropic support and donor age, gender, and mean ischemic time in hours (UWS 2 hours 36 minutes, range 1 hour 36 minutes to 2 hours 53 minutes; CCS 2 hours 20 minutes, range 1 hour 20 minutes to 2 hours 44 minutes; p = not significant) were similar. Significant differences observed between the two groups included (1) mean time (minutes) from reperfusion to achieve a stable rhythm, (2) need for intraoperative defibrillations, (3) need for transient cardiac pacing, and (4) integrated postoperative creatinine kinase and aspartate aminotransferase release over 48 hours. There was no difference in postoperative electrocardiogram, endomyocardial biopsy, or hemodynamics. One UWS patient died of sepsis and another of a ruptured cerebral aneurysm. UWS is safe for donor organ arrest and preservation despite high viscosity and potassium concentration. When compared with CCS hearts, hearts preserved in UWS regained electrical activity more rapidly and had better myocardial protection as demonstrated by enzymatic analysis. Further investigation is required to determine the effects of UWS preservation on long-term survival, to determine the prevalence of rejection and graft atherosclerosis, and to test the ability of UWS to extend donor ischemic time in human cardiac transplantation.
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PMID:University of Wisconsin solution versus crystalloid cardioplegia for human donor heart preservation. A randomized blinded prospective clinical trial. 173 83

With regard to cardiac findings in cocaine abuse, at autopsy the vast majority of patients dying with cocaine toxicity have either no pathologic change in the heart or only minimal changes that could not account for the patient's death. The second most frequent finding is underlying, mild-to-moderate coronary atherosclerosis, with or without coronary thrombosis. There may be acute or healed myocardial infarction or a sudden cardiac death without myocardial changes of ischemia. A high incidence of contraction band necrosis has been reported in the absence of coronary artery disease and may cause a sudden arrhythmic death. Myocarditis also has been described in a few cases as either lymphocytic or lymphocytic and eosinophilic infiltrate in the presence of myocyte necrosis. Usually, the foci are sparse and not always associated with contraction band necrosis. The underlying mechanisms are thought to be either direct effects of norepinephrine on myocytes or through vasospasm of resistance vessels and secondary myocardial ischemia. Cocaine rarely has been associated with aortic dissection, which is probably a result of cocaine's hypertensive effects.
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PMID:Cocaine-associated cardiovascular disease: clinical and pathological aspects. 174 14


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