Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Platelet behaviour (activation) in ischemic heart disease (stable angina) during pacing-induced tachycardia was studied. ECG was recorded during the trial. Ischemic heart disease (IHD) subjects had 75% or more narrowing of the luminal diameter of a coronary artery, demonstrated by coronary angiography. Eight subjects needing cardiac catheterism because of supraventricular rhythm disturbances with no evidence of IHD were studied as controls. Beta-thromboglobulin (beta-tg) and platelet factor 4 (PF4) were studied as platelet activation markers; beta-tg and PF4 were evaluated before atrial pacing in peripheral venous blood and, by catheterism, before and at maximum pacing rate in coronary venous sinus (CVS) and in ascending aorta (AA). Catheterism and blood withdrawals were performed in order to reduce platelet activation in vivo. No significant difference in platelet activation between IHD patients and control group in peripheral venous blood were found. No trans-myocardial gradient neither in IHD subjects nor in controls were observed. In conclusion, no platelet activation in IHD patients during pacing-induced tachycardia could be observed.
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PMID:No evidence of platelet activation during atrial pacing in subjects with stable angina. 252 53

Indexes of in vivo platelet activation, beta-thromboglobulin and platelet factor 4 were measured in triplicate in plasma from venous blood of 69 patients with proven ischaemic heart disease (IHD), discarding samples with a ratio of the plasma concentrations of the two proteins less than 2.6, in order to rule out sampling artifacts. Compared with 60 control volunteers, differences were not significant [for beta-thromboglobulin controls (ng ml-1, mean +/- SD) 27.8-8.6, ischaemic patients 32.3 +/- 17.1; for platelet factor 4 controls 4.3 +/- 1.4, ischaemic patients 5.9 +/- 5.7]. However, when patients were stratified according to disease activity (Group I--patients without spontaneous ischaemic episodes at rest during 4 days of continuous electrocardiographic monitoring; Group II--patients with less than 1 ischaemic episode/day; Group III--patients with greater than 1 episode/day), these indexes were increased in 'active' patients (for beta-thromboglobulin, in Group II--32.4 +/- 10.5 ng ml-1, P less than 0.05 vs. Group I; in Group III--42.6 +/- 14.6 ng ml-1, P less than 0.01 vs. Group I, P less than 0.05 vs. control. Platelet factor 4 was increased only in Group III--8.9 +/- 7.2 ng ml-1, P less than 0.05 vs. control). Beta-thromboglobulin and platelet factor 4 were 25.0 +/- 6.7 ng ml-1 and 4.9 +/- 4.8 ng ml-1, respectively, in Group I (P = NS vs. control). A relationship with the number of spontaneous ischaemic episodes at rest was confirmed by linear regression analysis (in Group III patients for beta-thromboglobulin: r = 0.76, P less than 0.01, and for platelet factor 4 r = 0.62, P less than 0.01). Levels were not elevated in patients with previous myocardial infarction without ischaemia at rest and/or patients with stable angina, and were not influenced by the occurrence of a positive exercise stress test. Coronary angiograms of ischaemic patients were analyzed to assess the extent and severity of atherosclerotic involvement: for both extent and severity, involvement was similar in the three groups. These data support the hypothesis of the occurrence of platelet activation in patients with spontaneous angina at rest, but not in other subsets of IHD patients, and establish the possibility of detecting in vivo platelet activation in IHD by means of such circulating markers.
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PMID:Platelet activation in angina at rest. Evidence by paired measurement of plasma beta-thromboglobulin and platelet factor 4. 297 44

Beta-thromboglobulin (beta TG) plasma levels were measured by radioimmunoassay in 14 patients with acute myocardial infarction (MI), in 13 with myocardial ischemia and recurrent episodes of angina and in 14 subjects with a past history of MI. Increased beta TG plasma values were observed in patients with acute MI and with myocardial ischemia whereas subjects with a past history of MI showed results not significantly different from normal subjects. Daily measurements in acute MI showed in five cases a second peak of beta TG values which suggests the occurrence of a deep vein thrombosis. The increased platelet consumption in MI was not related with the extent of the necrosis. We suggest, therefore, that platelet activation is associated with myocardial ischemia rather than necrosis.
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PMID:Beta-thromboglobulin in patients with acute and chronic coronary artery disease. 618 23