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Plasminogen activator inhibitor (PAI) is a marker of recurrence of myocardial infarction. Diabetes mellitus is also an important risk factor of coronary artery disease, including myocardial infarction and angina pectoris.We examined baseline plasma PAI activity levels, clinical variables, and angiographic findings and assessed them as prospective values for subsequent coronary events, such as sudden death, nonfatal myocardial infarction and coronary revascularization by percutaneous transluminal coronary angioplasty or coronary artery bypass surgery during the follow-up period.We conducted a prospective study for 4 years of 249 consecutive patients admitted with angina pectoris. Blood samples for PAI were drawn at discharge.In the multivariate Cox proportional hazard model, PAI activity and diabetes mellitus were significant and independent risk factors (the risk increased by 10% in those with a higher PAI concentration and by 70% in diabetic patients). Event-free survival was reduced by higher PAI activity (or = 8.4 IU/mL) and the presence of diabetes. The patients with higher PAI activity and diabetes had a 4.2-fold risk in comparison with the patients with lower PAI activity and no diabetes. However, patients with lower PAI activity were less likely to have coronary events even when they had diabetes.Higher PAI activity and diabetes predict subsequent coronary events in patients with angina pectoris. Diabetes has less prognostic value for subsequent coronary events in patients with lower PAI activity.

E-selectin, also known as endothelial cell leukocyte adhesion molecule-1, is a member of the selectin family of adhesion molecules and is expressed on vascular endothelial cells in inflammatory reactions. The induction of surface E-selectin expression by endothelial cells is considered a marker of activation.We examined the plasma soluble E-selectin (sE-selectin) level in 41 patients within 6 hours after the onset of acute myocardial infarction (AMI) and in 37 patients with stable exertional angina and 27 control patients. Blood samples were obtained on admission, after reperfusion therapy, and at 4 hours, 8 hours, 12 hours, 24 hours, 48 hours, 3 days, 5 days, 1 week, and 2 weeks after admission in the AMI group. In this group, 21 patients had a history of prodromal unstable angina before infarction and 20 had sudden onset of infarction. The plasma sE-selectin level (ng/mL) on admission was higher in the AMI group than in the stable exertional angina group and control group (38.5 +/- 3.1 vs 28.5 +/- 1.5, P.01, 26.0 +/- 1.8, P.01, respectively). In addition, plasma sE-selectin levels were higher in the patients with AMI with prodromal unstable angina than in those with a sudden onset of infarction on admission (44.7 +/- 5.4 vs 32.0 +/- 2.1, P.05). The plasma sE-selectin level decreased slowly during the chronic phase both in patients with AMI with prodromal unstable angina (from 44.7 +/- 5.4 to 33.8 +/- 3.4, P.01) and those with a sudden onset of infarction (from 32.0 +/- 2.1 to 24.9 +/- 2.4, P.01).These results suggest that an increase of sE-selectin may reflect enhanced endothelial cell activation in patients with AMI. The higher sE-selectin level in patients with AMI with prodromal unstable angina may have been associated with repeated episodes of myocardial ischemia and reperfusion.

OBJECTIVES We investigated the effects of enalapril therapy on plasma tissue factor (TF), tissue factor pathway inhibitor (TFPI) and monocyte chemoattractant protein-1 (MCP-1) levels in patients with acute myocardial infarction. BACKGROUND Macrophages express TF in human coronary atherosclerotic plaques. Both TF and TFPI are major regulators of coagulation and thrombosis. Monocyte chemoattractant protein-1 is a monocyte and macrophage chemotactic and activating factor. METHODS In a randomized, double-blind, placebo-controlled study beginning about two weeks after myocardial infarction, 16 patients received four weeks of placebo (placebo group) and another 16 patients received four weeks of enalapril 5 mg daily therapy (enalapril group). We performed blood sampling after administration of the doses. RESULTS There were no significant differences in the serum angiotensin-converting enzyme (ACE) activity, plasma TF, free TFPI or MCP-1 levels before administration between the enalapril and placebo groups. In the enalapril group, ACE activity (IU/liter) (14.0 before, 5.2 on day 3, 5.8 on day 7, 6.3 on day 28), TF levels (pg/ml) (223, 203, 182, 178) and MCP-1 levels (pg/ml) (919, 789, 790, 803) significantly decreased by day 28. However, the free TFPI levels (ng/ml) (28.2, 26.5, 26.8, 28.4) did not change. These four variables were unchanged during the study period in the placebo group. CONCLUSIONS This study demonstrated that administration of enalapril reduces the increased procoagulant activity in patients with myocardial infarction associated with inhibition of the activation and accumulation of macrophages and monocytes.

Protein C is one of the most important antithrombotic components. After activation by the thrombin-thrombomodulin complex on endothelial cells, activated protein C (APC) inactivates factors Va and VIIIa, which leads to the inhibition of thrombin formation. We examined the association of plasma levels of APC with the responsiveness to coronary thrombolytic therapy of the infarct-related coronary artery in patients with acute myocardial infarction (AMI). Plasma levels of APC, thrombin-antithrombin III complex (TAT), and plasminogen activator inhibitor (PAI) activity were measured in 32 consecutive AMI patients who underwent coronary angiography followed by thrombolytic therapy, and compared to the measurements in 23 control subjects. On admission, APC levels (ng/mL) were significantly elevated in patients with AMI, as compared with controls (2.5+/-0.4 vs. 1.2+/-0.2, 1.3+/-0.2, respectively, p0.01). At discharge, plasma levels in AMI patients decline to values not significantly different from those in controls. (1.2+/-0.2, 1.3+/-0.2, respectively). TAT levels (ng/mL) were different among the groups in a fashion similar to that of APC (14.1+/-3.1 on admission vs. 3.3+/-0.4 at discharge, 1.8+/-0.1 in the control subjects, respectively, p0.01). PAI activity levels (IU/mL) were higher on admission than at discharge and higher than the control subjects (19.7+/-1.8 vs. 10.5+/-1.0, 5.4 +/- 0.7, respectively, p0.01). Thirty-two patients with AMI were classified into two groups according to the results of thrombolysis: the success group (24 patients) and the failure group (eight patients). APC levels were higher in the failure group than in the success group (5.1+/-0.7 vs. 1.6+/-0.2, p0.01). TAT levels were also higher in the failure group than in the success group (30.8+/-9.6 vs. 8.6+/-1.7, p0.01). PAI activity levels (IU/mL) were lower in the failure group than in the success group (13.5+/-3.1 vs. 21.7+/-2.1, p0.05). There were correlations between APC and TAT levels both on admission (r=0.75, p0.0001) and at discharge (r=0.71, p0.0001). Elevated APC was thought to correlate with increased thrombin generation in patients with AMI. This study demonstrated that there was a significant relation between plasma APC level and the responsiveness to thrombolytic therapy of the infarct artery. This study may also indicate that increased thrombin generation is a cause of the resistance to thrombolytic therapy.

Background —This study was designed to evaluate the plasma levels of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in patients with unstable angina and investigate whether there is a relationship between these levels and unfavorable outcome. Methods and Results —The plasma TF and free TFPI antigen levels were determined in plasma samples taken from 51 patients with unstable angina, 56 with stable exertional angina, and 55 with chest pain syndrome. The plasma TF and free TFPI antigen levels were higher in the unstable angina group than in the stable exertional angina and chest pain syndrome group. There was a good correlation between TF and TFPI. We established borderline as maximum level in the patients with chest pain syndrome. Seven patients (of the 22 in the high TF group) required revascularization to control their unstable angina during in-hospital stay. On the other hand, only 1 of the 29 patients in the low TF group required myocardial revascularization. Four patients of the 14 patients in the high free TFPI group required myocardial revascularization during in-hospital stay, and 4 of the 37 patients in the low free TFPI group required myocardial revascularization. We compared the TF and free TFPI levels between the cardiac event (+) group and cardiac event (−) group. TF levels were significantly higher in the cardiac event (+) group than in the cardiac event (−) group. Conclusions —We have demonstrated that not only the plasma TF levels but also the plasma-free TFPI levels are elevated in patients with unstable angina. Patients with unstable angina and heightened TF and free TFPI are at increased risk for unfavorable outcomes. The heightened TF level was a more important predictor in patients with unstable angina.

The hypercoagulability is associated with expression of tissue factor in patients with angina. Tissue factor pathway inhibitor regulates the extrinsic coagulation pathway mediated by tissue factor. Plasma samples were obtained from 14 patients with angina pectoris and 9 with chest pain syndrome before and 5, 30, 60, and 120 minutes after administration of heparin (50 IU/kg). The tissue factor and prothrombin fragment 1+2 levels before administration were elevated in patients with angina pectoris and were reduced to the levels of chest pain syndrome after the administration. The free tissue factor pathway inhibitor levels after the administration were higher in patients with angina pectoris than in patients with chest pain syndrome. Plasma tissue factor pathway inhibitor levels correlated positively with plasma tissue factor and prothrombin fragment 1+2 levels. We showed that plasma-free TFPI levels after administration of heparin, which may indicate endothelial cell associated TFPI levels, increased in patients with angina pectoris compared with patients with chest pain syndrome. Increased endothelial cell associated TFPI was associated with hypercoagulability in patients with angina pectoris. These may help to explain the reduction in thrombotic risk associated with the use of heparin.

It has been suggested that active inflammation plays an important role in the pathogenesis of acute coronary syndromes, including unstable angina. Intracellular adhesion molecule-1 (ICAM-1) is a major ligand on the endothelial cells for adherence of the activated polymorphonuclear leukocytes. Recently, it has been demonstrated that the soluble form of ICAM-1 has been detected in human serum and has been increased in many other inflammatory or autoimmune disorders. To evaluate the involvement of ICAM-1 in unstable angina, we examined plasma soluble ICAM-1 (sICAM-1) levels in coronary circulation. The plasma sICAM-1 levels in the coronary sinus and aortic root were simultaneously examined in 20 patients with unstable angina, 19 patients with stable exertional angina, and 16 control subjects. The plasma levels of sICAM-1 were measured by enzyme-linked immunosorbent assay. The mean plasma sICAM-1 levels (nanograms per milliliter) both in the coronary sinus and aortic root were significantly higher (p0.01) in patients with unstable angina than in those with stable exertional angina and in control subjects (217+/-14 vs 126+/-8; 120+/-10 in the coronary sinus, 202+/-13 vs 125+/-9; 123+/-10 in the aortic root). Furthermore, the mean value was higher in the coronary sinus than in the aortic root in patients with unstable angina. There were no significant differences in the values between in the coronary sinus and aortic root in patients with stable exertional angina and control subjects. Thus, sICAM-1 release is increased, especially in coronary circulation in unstable angina.

Objectives. This study sought to examine effect of vitamin C, an antioxidant, on the abnormal vasomotor reactivity in spasm coronary arteries.Background. Oxygen free radicals generated in the arterial walls have been shown to cause endothelial vasomotor dysfunction.Methods. Responses of the epicardial arterial diameters of the left coronary arteries to the intracoronary infusion of acetylcholine (ACh) (10 and 50 μg/min) were measured by quantitative coronary angiography before and during combined intracoronary infusion of vitamin C (10 mg/min) or saline as a placebo in 32 patients with coronary spastic angina and in 34 control subjects.Results. Vitamin C infusion suppressed the constrictor response of the epicardial diameter to ACh in spasm coronary arteries but had no significant effect in the control coronary arteries (percent change in distal diameter in response to 10 μg/min of ACh [constriction (−), dilation (+), mean ± SEM] before vitamin C: −8.2 ± 2.9% in spasm arteries, +8.4 ± 2.9%∗ in control arteries; during vitamin C: +0.2 ± 3.8%∗ in spasm arteries, +7.2 ± 1.3%∗ in control arteries [∗p < 0.01 vs. spasm arteries before vitamin C]). The coronary sinus–arterial difference in plasma thiobarbituric acid reactive substances during ACh infusion, an indicator of lipid peroxidation in coronary circulation, was higher in patients with coronary spastic angina than in control subjects (p < 0.01) but was suppressed in patients with coronary spastic angina to comparable levels in control subjects by combined infusion of vitamin C. Saline infusion had no effect.Conclusions. The results indicate that vitamin C attenuates vasomotor dysfunction in epicardial coronary arteries in patients with coronary spastic angina. Oxygen free radicals may at least in part play a role in the abnormal coronary vasomotor reactivity in response to ACh in spasm coronary arteries.

Tissue factor pathway inhibitor (TFPI) is known to inhibit the initial reaction in the tissue factor-mediated coagulation pathway. We measured plasma free-form TFPI antigen levels and monitored 24-h Holter recordings at 06.00, 14.00 and 22.00 h in 15 patients with coronary spastic angina, 13 patients with stable exertional angina, and 11 control subjects. There was a significant circadian variation in plasma free-form TFPI antigen levels in patients with coronary spastic angina (25.8±2.0 ng/ml at 06.00 h, 21.1 ±1.6 ng/ml at 14.00 h, 20.2±1.4 ng/ml at 22.00 h; p

We have reported that the plasma levels of plasma fibrinopeptide A and plasminogen activator inhibitor activity increase in patients with unstable angina and acute myocardial infarction. Tissue factor (TF) is a low-molecular-weight glycoprotein that binds to and acts on essential cofactor VII, and the resulting complex activates factors IX and X, initiating the coagulation cascade. We measured plasma TF antigen levels in 21 patients with unstable angina (on admission and after treatment), 27 patients with stable exertional angina, and 27 control subjects. The 3 groups were matched for age, gender, and other clinical variables. The plasma TF antigen levels were higher in the unstable angina group than in the stable exertional angina and control groups (240 +/- 75 vs 184 +/- 46 and 177 +/- 37 pg/ml, p0.01). There were no significant differences in the plasma TF antigen levels between the stable exertional angina and the control groups. Furthermore, the plasma TF antigen levels were reexamined after treatment in the 21 patients with unstable angina. The mean level in these 21 patients decreased after 2 weeks of treatment (from 240 +/- 75 to 206 +/- 57 pg/ml, p0.01). This study suggests that the plasma TF antigen levels correlate with disease activity in patients with unstable angina. The increased plasma TF antigen levels in patients with unstable angina may reflect intravascular procoagulant activity.

A 66-year-old woman was admitted to the hospital with a cerebral hemorrhage. An echocardiogram showed severe left ventricular hypokinesis and a left ventricular thrombus. An electrocardiogram showed ST segment elevation in the precordial leads. The patient's creatine kinase level was elevated. A follow-up echocardiogram performed 1 month after admission showed normalization of left ventricular wall motion and disappearance of the thrombus. The results of thallium myocardial scintigraphy, coronary arteriography, and left ventriculography performed 1 month after admission were normal, and the patient was discharged without clinical sequelae. The cause of the patient's left ventricular dysfunction was believed to be not myocardial infarction or myocarditis, but a massive adrenergic discharge due to the cerebral hemorrhage.

The levels of circulating monocyte chemoattractant protein-1 (MCP-1) and tissue factor (TF) were examined on admission in 46 consecutive patients with acute coronary syndromes (ACS) and 30 patients with stable exertional angina (SEA). The plasma levels of both MCP-1 and TF were higher in the ACS patients than in the SEA patients (MCP-1: p

We examined plasma TF and free TFPI levels in 26 consecutive patients with AMI, 26 patients with stable exertional angina, and 25 patients with chest pain syndrome. In patients with AMI, blood samples were obtained immediately after admission and at 4, 8, 16, 24, and 48 h, and the third, fifth, seventh, and fourteenth day after initiation of reperfusion therapy. Plasma TF levels in patients with AMI on admission were significantly higher than in the chest pain syndrome and stable exertional angina groups (248.0+/-117. 4 vs. 179.5+/-29.2 vs. 189.5+/-29.6 pg/ml, P

Vascular endothelial growth factor (VEGF) is a growth factor for vascular endothelial cells in vitro. The present study was designed to determine whether serum VEGF levels increase in patients with acute myocardial infarction (AMI) compared with patients with stable exertional angina and control subjects, and to examine the serial changes of serum VEGF levels in patients with AMI. We examined serum VEGF levels by using antibody prepared from serum immunized with human VEGF121. The serum VEGF level (pg/ml) was higher (p < 0.0001) on admission in the patients with AMI (177 ± 19) than in those with stable exertional angina (61 ± 7) and control subjects (62 ± 6). The serum VEGF level (pg/ml) of the patients with AMI was 177 ± 19 on admission, 125 ± 9 on day 3, 137 ± 11 on day 5, 242 ± 18 at 1 week, and 258 ± 22 at 2 weeks after admission. The value was higher on admission than on day 3 after admission (p = 0.014), the values were higher at 1 week and 2 weeks than on admission, on day 3, and 5 (p < 0.01). Furthermore, there were correlations between peak VEGF levels at 1 week or 2 weeks after admission and peak creatine kinase levels. The increase of VEGF on admission in the patients with AMI may be due to the hypoxia of acute myocardial ischemia. The elevation at 1 week and 2 weeks from the onset may cause the development of collateral circulation in relation to the healing of the infarction site.

An elevated level of angiotensin-converting enzyme (ACE) has been demonstrated to increase the risk of myocardial infarction. Plasminogen activator inhibitor (PAI) is the most important physiological inhibitor of tissue plasminogen activator in plasma. An elevated level of PAI has been reported to be associated with decreased fibrinolytic capacity and to constitute a marker of the risk for recurrent coronary thrombosis.We measured the serum ACE activity and plasma PAI activity in 34 patients with recent myocardial infarction, and evaluated the correlation between these two values by linear regression analysis. We also administered captopril (37.5 mg/day) to 17 of these patients and placebo to the other 17 patients at random, and compared the changes in PAI activity and ACE activity in these two groups over a 1-month period.There was a significant correlation between the serum ACE activity and the plasma PAI activity at baseline in the patients (r = 0.498, P0.01). The captopril-treated patients showed significantly reduced PAI activity (P0.01), and a concomitant decrease in ACE activity.These results suggest that elevated ACE activity is associated with impaired fibrinolysis and that treatment with an ACE inhibitor improves the fibrinolytic function in patients with recent myocardial infarction. The results also suggest that the renin-angiotensin system plays a role in the increased risk of ischemic cardiovascular events when it is activated, and in the reduction of risk of recurrent myocardial infarction by ACE inhibition.

Background —It remains undetermined whether triglyceride-rich lipoproteins are an independent risk factor for atherosclerosis. Methods and Results —The correlation of responses of coronary arterial diameter (quantitative coronary angiography) and coronary blood flow (intracoronary flow wire technique) to intracoronary infusion of acetylcholine (10 and 50 μg/min) with coronary risk factors including remnant lipoprotein levels was statistically analyzed in 106 consecutive subjects with normal coronary angiograms. Remnant lipoproteins were isolated from fasting blood with an immunoaffinity mixed gel containing anti–apolipoprotein (apo) A-1 and anti–apoB-100 monoclonal antibodies. In multivariate stepwise regression analysis, remnant lipoprotein levels had the most significant correlation with abnormal epicardial coronary vasomotor responses to acetylcholine infusion, reflected by impaired dilation or constriction of the epicardial coronary arteries, and the levels also had an inverse and independent correlation with the coronary blood flow increase in response to acetylcholine. In a subgroup of 53 consecutive subjects, constrictor responses of epicardial coronary diameters to intracoronary infusion of N G -monomethyl- l -arginine (50 μmol/min for 4 minutes) at baseline, reflecting the presence of coronary nitric oxide bioactivity, had an inverse and independent correlation with remnant lipoprotein levels by use of multivariate analysis. Conclusions —Remnant lipoprotein levels were independently associated with abnormal endothelium-dependent vasomotor function in large and resistance coronary arteries in humans, indicating that remnant lipoproteins may impair endothelial vasomotor function in human coronary arteries. The decrease in coronary nitric oxide bioactivity may be responsible in part for the inhibitory effects of remnant lipoproteins.

Tissue factor pathway inhibitor (TFPI) is a physiological regulator of the extrinsic coagulation cascade. Coronary spasm can alter endothelial cell properties in the coronary artery with resultant thrombosis. To determine whether coronary spasm affects plasma TFPI level, we measured the heparin-releasable endothelial cell-associated TFPI (heparin-releasable TFPI) (ng/ml) in the coronary sinus and the aortic root before and after coronary spasm induced by an injection of acetylcholine in 18 patients with coronary spastic angina, and before and after myocardial ischemia induced by rapid atrial pacing in 18 patients with stable exertional angina, and in 17 control subjects with normal coronary arteries and no coronary spasm. Heparin-releasable TFPI level in the coronary spastic angina group significantly increased in the coronary sinus (1 22+/-46 to 147+/-63, p

The present study examines whether an acute inflammatory response occurs during acute myocardial infarction (AMI) by measuring soluble P-selectin levels. We examined plasma soluble P-selectin levels in 16 consecutive patients with AMI, in 15 patients with angina, and in 13 control subjects with chest pain but normal coronary arteries and no coronary spasm. In patients with AMI, blood samples were obtained immediately after admission and at 1, 4, 24, and 48 hours, and 1 week after initiation of reperfusion therapy. The plasma soluble P-selectin levels were significantly higher in the AMI group on admission than in the other 2 groups (83 +/- 13 ng/ml, p0.01). The plasma soluble P-selectin levels at baseline were not significantly different between the angina and control groups (28 +/- 4 vs 24 +/- 5 ng/ml, p = NS). Plasma soluble P-selectin levels reached their peak significantly at 4 hours after initiation of the reperfusion therapy in patients with AMI. The peak level was significantly higher than the level on admission (115 +/- 17 vs 83 +/- 13 ng/ml, p0.05). The plasma soluble P-selectin levels were higher in the AMI group than in the angina and control groups over the time course (p0.01). Our data indicate that the plasma soluble P-selectin levels are increased in patients with AMI, and that the levels are increases after reperfusion therapy more than before reperfusion. We suggest that the increase in the plasma soluble P-selectin levels may be caused by the activation of endothelial cells and platelets after myocardial ischemia and reperfusion during AMI.