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Biomedical subjects

F Andreotti

Publications and source records attributed to F Andreotti.

At least 19 recordsLinked to original sources
PubMed2002

Increased prevalence of the G20210A prothrombin gene variant in acute coronary syndromes without metabolic or acquired risk factors or with limited extent of disease.

AIMS: To investigate the prevalence of the G20210A prothrombin and G1691A factor V gene variants in patients with acute coronary syndrome stratified according to risk factor profile and to extent of coronary disease, in comparison with matched healthy controls. METHODS AND RESULTS: The 20210 prothrombin and the 1691 factor V loci were genotyped in 247 patients < or =65 years of age (190 myocardial infarction and 57 unstable angina as first presentation of disease) and in 247 healthy age- and sex-matched controls. The prevalence of the 1691A factor V allele was similar in cases and controls. The frequency of heterozygotes for the 20210A prothrombin allele was 6.5% among patients and 2.8% among controls (OR 2.4, 95% CI 1.0-5.9), increasing to 8.7% in patients with a family history of myocardial infarction (OR 3.3, 95% CI 1.2-9.1), to 9.9% in patients (n=81) with < or =1 vessel disease (OR 3.8, 95% CI 1.3-10.8), and to 13.0% in patients who were normocholesterolaemic, non-diabetic, normotensive and non-smokers (OR 5.1, 95% CI 1.2-21.4). CONCLUSIONS: These findings suggest that the 20210A prothrombin allele represents an inherited risk factor for acute coronary syndrome among patients who have limited extent of coronary disease at angiography or who lack major metabolic and acquired risk factors.

Acute Disease↗
PubMed2002

Inflammatory gene polymorphisms and ischaemic heart disease: review of population association studies.

Inflammation and genetics are both prominent mechanisms in the pathogenesis of atherosclerosis and arterial thrombosis. Accordingly, a number of population studies have explored the association of ischaemic heart disease with gene polymorphisms of the inflammatory molecules tumour necrosis factors (TNF) alpha and beta, transforming growth factors (TGF) beta1 and 2, interleukin (IL) 1 and its receptor antagonist (IL 1ra), CD14 (the receptor for lipopolysaccharide), P and E selectins, and platelet endothelial cell adhesion molecule (PECAM) 1. Although they are very preliminary and partly conflicting, the data provide some evidence that alterations in the genetics of the inflammatory system may modify the risk of ischaemic heart disease.

Adult↗
PubMed2001

Relation of the -174 G/C polymorphism of interleukin-6 to interleukin-6 plasma levels and to length of hospitalization after surgical coronary revascularization.

Interleukin (IL)-6 plasma levels are predictive of major cardiovascular events. The -174 G/C promoter polymorphism of the IL-6 gene affects basal levels in vivo and transcription rates in vitro, but its association with IL-6 acute phase levels among patients with coronary artery disease has not been investigated. In 111 patients with multivessel coronary artery disease undergoing elective coronary artery bypass graft surgery, we prospectively assessed genotype at position -174 and serial blood levels of IL-6 and other inflammatory indexes. Clinical and surgical characteristics did not differ among genotypic groups. IL-6 levels--measured daily up to 72 hours before surgery, after surgery, and at discharge--showed a mean 17-fold increase, peaking at 24 hours (p <0.0001). IL-6 levels (but not fibrinogen, white-blood cell count, and C-reactive protein values) differed significantly according to the -174 genotype (p = 0.042 for difference between areas under the curve), the 62 GG homozygotes exhibiting higher concentrations than the 49 carriers of the C allele (widest difference at 48 hours, p = 0.015 in multivariate analysis). GG homozygosity was associated with longer stays in the intensive care unit (2.5 +/- 3.4 vs 1.4 +/- 0.9 days, p = 0.02) and in the hospital (6.7 +/- 4.0 vs 5.3 +/- 1.4 days, p = 0.02) than C carriership. Rates of postoperative death, myocardial infarction, and stroke were 8% in GG homozygotes and 2% in C-carriers (p = 0.16). The IL-6-174 GG genotype is associated with higher acute phase levels of IL-6 and with longer stays in the hospital and in the intensive care unit than C allele carriership after surgical coronary revascularization.

C-Reactive Protein↗
PubMed2001

Coronary artero-venous gradient of endogenous urokinase.

Experimental data indicate that urokinase-type plasminogen activator (u-PA) contributes significantly to endogenous fibrinolysis and vascular remodeling in proportion to its local concentrations. In humans, however, it is not known whether u-PA levels vary at different sites and across specific vascular beds. We investigated possible regional and artero-venous differences in plasma u-PA concentrations in 15 patients undergoing cardiac catheterization. Three pairs of simultaneous samples were taken from: (1) the ascending aorta and coronary sinus; (2) left ventricle and right atrium; (3) femoral artery and femoral vein. Single-chain urokinase-type plasminogen activator (scu-PA) was measured by bioimmunoassay, and total u-PA antigen (including scu-Pa and two-chain urokinase-type plasminogen activator complexed with inhibitors (tcu-PA)) by enzyme-linked immunosorbent assay. Scu-PA represented, on average, 51+/-15% of total u-PA concentrations. Scu-PA and total u-PA levels were correlated (r=.72, P<.0001) and did not differ significantly among the arterial or venous locations. There was a small but consistent increase in mean (+/-standard deviation (S.D.)) scu-PA concentrations from all arterial to all venous samples (1.5+/-0.6 vs. 1.6+/-0.5 ng/ml, P=.038) and from ascending aorta to coronary sinus (1.6+/-0.5 vs. 1.7+/-0.6 ng/ml, P=.046). Similarly, total u-PA levels increased from femoral artery to femoral vein (2.9+/-0.7 vs. 3.0+/-0.8 ng/ml, P<.001). In contrast, across the lungs, no significant concentration-gradient was seen in either scu-PA or total u-PA. The changes in total u-PA roughly followed those of scu-PA. These data identify an artero-venous gradient in human plasma u-PA across the coronary and peripheral beds, but not across the lungs, suggesting differences in u-PA kinetics according to vascular location.

Aged↗
PubMed2001

Low-grade exercise enhances platelet aggregability in patients with obstructive coronary disease independently of myocardial ischemia.

Moderate and strenuous exercise is known to enhance platelet aggregability in patients with obstructive coronary artery disease (CAD), but the effect of low-grade exercise is not known. We assessed shear-induced platelet aggregability before and after mild exercise (less than or equal to stage III of the modified Bruce protocol) in 27 patients with documented CAD who were receiving aspirin and in 12 subjects without CAD (controls). Ex vivo platelet aggregability was assessed in flowing whole blood as the time to occlude a collagen and adenosine diphosphate-coated ring; shorter times indicated greater aggregability. Aggregability, plasma von Willebrand factor (vWF) antigen, platelet and white cell counts, and hematocrit were measured at baseline, immediately after exercise (peak), and at 30 and 180 minutes after exercise. Exercise of similar workloads induced myocardial ischemia in 14 patients (group 1), but not in the other 13 (group 2) nor in controls. Both patient groups showed a reduction in aggregation time at peak exercise compared with baseline (group 1: 84+/-17 seconds at peak vs 96+/-22 seconds at baseline; group 2: 84+/-20 seconds at peak vs 99+/-20 seconds at baseline; p <0.03 for both comparisons), with a return to baseline values within 180 minutes. No significant variation occurred in controls (89+/-18 seconds at peak vs 85+/-21 second at baseline). Changes in vWF antigen did not differ significantly among groups. Aggregation times did not correlate with hematocrit or platelet and white cell counts. Thus, even low-grade exercise transiently enhances whole blood platelet aggregability in patients with obstructive CAD, but not in controls. The effect is independent of myocardial ischemia, occurs despite aspirin, and is likely dependent on hemodynamic factors interacting with coronary obstructions or dysfunctional endothelium.

Aged↗
PubMed2001

Markedly reduced insulin-like growth factor-1 in the acute phase of myocardial infarction.

OBJECTIVES: We investigated whether insulin-like growth factor-1 (IGF-1) is reduced in the early phase of acute myocardial infarction (AMI) and whether such a decrease might influence prognosis. BACKGROUND: Insulin-like growth factor-1 protects against insulin resistance and apoptosis. Although insulin resistance has been reported in AMI, IGF-1 levels have not been investigated. METHODS: We measured serum IGF-1 in 23 patients with AMI within 24 h of symptom onset and in 11 matched controls. In the first 12 patients and controls, we also measured fasting insulin, diurnal growth hormone (GH) and insulin sensitivity (assessed as glucose disappearance or T/2 after an insulin bolus), and repeated IGF-1, insulin and GH after one year. In all patients, 90-day cardiovascular death, recurrent ischemia, reinfarction, revascularization and late malignant arrhythmias were assessed. RESULTS: The AMI patients versus controls showed markedly reduced IGF-1 (115 +/- 112 vs. 615 +/- 300 ng/ml, p < 0.0001) and slower T/2 (-0.98 +/- 1.5 vs. -2.57 +/- 1.0 mg/dl/min, p = 0.01). Low IGF-1 often preceded the rise of myocardial necrosis markers. Patients with 90-day events (n = 12) versus those without had lower IGF-1 (47 +/- 54 vs. 189 +/- 110 ng/ml, p < 0.0001). Acute phase GH and insulin concentrations did not differ significantly from controls. After one year, the patients' IGF-1 values had risen to 460 +/- 242 ng/ml (p = 0.1 vs. controls, p < 0.0005 vs. acute phase), whereas GH levels were lower (0.2 +/- 0.2 vs. 2.5 +/- 2.3 ng/ml, p = 0.01) and insulin levels higher (12.5 +/- 0.2 vs. 3.9 +/- 2.6 microU/ml, p < 0.0001) compared with controls. CONCLUSIONS: In the early phase of AMI, serum IGF-1 levels are markedly reduced and may contribute to adverse outcomes. Reduced IGF-1 preceding the rise of myocardial necrosis markers suggests a possible pathogenetic role. A compensatory increase in IGF-1 appears to occur by one year.

Aged↗
PubMed2001

The C807T/G873A polymorphism in the platelet glycoprotein Ia gene and the risk of acute coronary syndrome in the Italian population.

Membrane glycoprotein (GP) Ia/IIa mediates platelet adhesion to collagen. The linked C807T/G873A polymorphisms in the GP Ia gene are correlated with a variable expression of the platelet surface receptor, the 807 TT/873 AA genotype being associated with a higher receptor density. Our study aimed to evaluate the possible role of the GP Ia C807T/G873A polymorphism as a risk factor for acute coronary syndrome in the Italian population. We investigated 157 patients with acute coronary syndrome (117 with myocardial infarction and 40 with severe unstable angina) as the first manifestation of coronary disease occurring before 65 years of age, compared with 312 healthy controls. All individuals were of Italian ancestry and were genotyped for the GP Ia C807T/G873A polymorphism. Complete linkage between the 807 and 873 sites was found in all samples. The 807 TT genotype was present in 12.7% of cases and in 4.8% of controls; the odds ratio for acute coronary syndrome was 2.9 (95% CI 1.4--5.8) for the 807 TT genotype compared with C-allele carriers and 0.6 (95% CI 0.4--0.9) for the 807 CC genotype compared with T-allele carriers. For the TT genotype, compared with CC homozygotes, the increase in risk was 3.4-fold in patients with at least one risk factor (smoking, hypercholesterolaemia, diabetes, systemic hypertension) and 4.1-fold in patients with angiographically diagnosed two- or three-vessel disease. We conclude that the GP Ia 807 TT (873 AA) genotype is associated with an increased risk of acute coronary syndrome in the Italian population; conversely, the GP Ia 807 CC (873 GG) genotype seems to represent a protective factor.

Acute Disease↗
PubMed2001

Platelet aggregability in cardiac syndrome X.

AIMS: To assess platelet aggregability at rest and in response to exercise in patients with cardiac syndrome X (anginal chest pain, ST-segment depression on exercise, angiographically normal coronary arteries). METHODS AND RESULTS: We performed a symptom/sign-limited exercise test in 31 patients with syndrome X, 25 patients with coronary artery disease and 29 healthy subjects. Platelet aggregability was measured in flowing whole blood at baseline, at peak exercise, and after 30 and 120 min, as the time to occlude a collagen/adenosine diphosphate coated ring (aggregation time). Resting aggregation time was shorter in syndrome X patients (83.2+/-12 s), compared to patients with coronary disease (94.0+/-18 s, P<0.01) and to healthy subjects (96.4+/-21 s, P<0.01). With exercise, aggregation time did not change in healthy controls, decreased in patients with coronary disease (-13.8 s at peak; 95% CI, -10.2, -17.3 s;P<0.001), but increased in syndrome X (+17.4 s 30 min after exercise; 95% CI, +10.4, +24.4 s;P<0.0001). The intravenous administration of an adenosine antagonist (theophylline) prevented the exercise-induced prolongation of aggregation time in syndrome X patients (n=11), but had no effect in healthy controls (n=11). CONCLUSION: Platelet aggregability at rest was increased in syndrome X patients, compared to patients with coronary artery disease and healthy subjects. In contrast to patients with coronary disease, however, platelet aggregability was reduced by exercise. This response was prevented by theophylline, strongly suggesting the involvement of adenosine.

Aged↗
PubMed2000

Homocysteine and risk of cardiovascular disease.

This pictorial introduction to homocysteine illustrates at a glance the nature of homocysteine and its role in cardiovascular disease by means of eight simple figures and an essential bibliography. Homocysteine is a sulfur-containing metabolite of methionine. Conversion back to methionine or transsulfuration to cysteine are the two major metabolic pathways that reduce total homocysteine (tHcy) concentrations in cells and blood. B vitamins are essential cofactors in homocysteine metabolism. Median fasting total homocysteine levels in adult males are approximately 10 micromol/L. Increased plasma tHcy concentrations are found with methionine-rich diets, low vitamin B intake, male gender, age, impaired renal function, and genetically determined defects of the enzymes involved in homocysteine metabolism. An inverse relation exists between plasma tHcy and circulating folate or vitamin B(6) concentrations, and folic acid supplements of 0.5 mg/d can reduce tHcy levels by approximately 25%. Homocystinuric patients, who have severe hyperhomocysteinemia, die prematurely of atherothrombotic disease. Many (but not all) cross-sectional and prospective studies indicate, on average, that plasma tHcy levels <.10 micromol/L are associated with, or predict the development of, coronary, cerebral, and peripheral vascular disease. The risk conferred by hyperhomocysteinemia is graded and is independent of traditional risk factors, with an estimated odds ratio for ischemic heart disease of 1.4 for every 5 micromol/L increase in plasma tHcy. In vitro and in vivo, tHcy has been found to impair endothelial function. It is now well established that tHcy represents a marker of current or subsequent ischemic vascular disease. However, irrefutable proof that hyperhomocysteinemia actually causes atherothrombosis will come only if interventions to lower plasma tHcy will produce concomitant reductions in cardiovascular events.

Arteriosclerosis↗
PubMed2000

Ticlopidine and aspirin fail to suppress the increased platelet aggregability that follows percutaneous coronary interventions.

Previous studies indicate that percutaneous transluminal coronary angioplasty (PTCA) is associated with platelet activation. It is not well-established whether enhanced platelet aggregability after PTCA is prevented by the association of ticlopidine with aspirin. The aim of this study was to evaluate whole blood platelet aggregability before and after elective PTCA in patients with chronic stable angina receiving ticlopidine and aspirin. We studied 16 patients referred for elective PTCA, treated for > or = 72 hours with oral aspirin and ticlopidine (group 1), and 10 patients referred for diagnostic coronary angiography, treated with oral aspirin alone (group 2). An intravenous bolus of heparin was administered at the start of PTCA. In both groups, platelet aggregability was assessed at baseline and 24 hours after the procedure, using the PFA 100(R) system. This method measures the time required for flowing whole blood to occlude a collagen and adenosine diphosphate (ADP)-coated ring, shorter times indicating greater aggregability. In both groups, platelet aggregability after the procedure was significantly increased compared with baseline: 104+/-30 seconds before versus 88+/-24 seconds at 24 hours in group 1 (p=0.03) and 84+/-16 seconds before versus 69+/-14 seconds at 24 hours in group 2 (p=0.004). Group 1 patients, compared with group 2, showed a trend toward reduced aggregability at baseline (p=0.06) and significantly lower aggregability 24 hours after the procedure (p=0.03). Ticlopidine and aspirin reduce whole-blood platelet aggregability compared with aspirin alone but fail to suppress the increased aggregability that occurs 24 hours after PTCA.

Aged↗
PubMed2000

Reversible left anterior descending artery spasm, prolonged cardiac arrest and left main thrombosis during a PTCA attempt of the circumflex artery.

The authors report a case of percutaneous transluminal coronary angioplasty of the circumflex artery complicated by occlusion of the non-diseased left anterior descending artery by spasm. During advanced cardiac life support, required for the subsequent cardiac arrest, intra-coronary nitrates and calcium antagonists were administered. After 45 minutes, the spasm resolved, but N probably as a result of prolonged blood stasis N a thrombus appeared in the left main artery. While attempting to stent the left main, the thrombus was mechanically dislodged, leaving the epicardial coronary tree free, with a good flow.

Angioplasty, Balloon, Coronary↗
PubMed2000

Vascular and haemostatic gene polymorphisms associated with non-fatal myocardial infarction: a critical review.

The importance of genetics to the pathogenesis of myocardial infarction is suggested by the frequent familial clustering of premature disease. Yet, studies associating myocardial infarction with gene polymorphisms of vascular proteins (angiotensinogen, angiotensin converting enzyme, angiotensin II type 1 receptor, endothelial nitric oxide synthase) and haemostatic factors (fibrinogen, coagulation factors II, V, VII and XIII, plasminogen activator inhibitor-1, tissue-type plasminogen activator, platelet glycoproteins IIb/IIIa, Ia/IIa and Ib-IX-V, or methylenetetrahydrofolate reductase) have revealed conflicting results. This is hardly surprising, given: 1) the multigenic nature of myocardial infarction, whereby single polymorphisms are bound to play at best only a limited role in the global risk of disease; 2) the multiple pathogenetic mechanisms of infarction (e.g., atheromatous obstruction, plaque rupture, thrombosis, vasospasm), each of which is likely influenced by a number of genes and by several environmental factors. The simultaneous investigation of a set of polymorphisms--and of their interactions with environmental factors--in extremely homogeneous sets of patients should offer a better understanding of the contribution of specific genes to the risk of myocardial infarction.

Angiotensinogen↗