Heidi Grundt

Reduction in Homocysteine by n-3 Polyunsaturated Fatty Acids after 1 Year in a Randomised Double-Blind Study following an Acute Myocardial Infarction: No Effect on Endothelial Adhesion Properties

We hypothesized that n–3 polyunsaturated fatty acids (n–3 PUFAs) as compared to corn oil administered for 1 year following an acute myocardial infarction (MI) may reduce plasma total homocysteine (p-tHcy), ultrasensitive C-reactive protein (µCRP), and the adhesive properties of the endothelium, expressed as soluble E-selectin (sE-selectin) and soluble intercellular adhesion molecule-1 (sICAM-1). In a prospective, randomised, double-blind study, 300 acute MI patients were allocated to highly concentrated n–3 PUFAs (n = 150) or corn oil (n = 150). After 1 year on treatment there was an intergroup difference in p-tHcy in favour of the n–3 group (n = 118), p = 0.022. However, sE-selectin, sICAM-1 and µCRP were unaffected by the treatment. In conclusion, reduction of p-tHcy by long-term n–3 PUFAs treatment was not associated with demonstrable effects on markers of endothelial adhesion properties.

Improvement of serum lipids and blood pressure during intervention with n‐3 fatty acids was not associated with changes in insulin levels in subjects with combined hyperlipidaemia

Abstract. Objectives. To investigate the effect of an omega‐3 fatty acid concentrate K85 on serum lipids, lipoproteins, insulin metabolism and blood pressure in subjects with combined hyperlipidaemia.

Increased lipid peroxidation during long-term intervention with high doses of n-3 fatty acids (PUFAs) following an acute myocardial infarction

Objective: To assess the oxidative burden of a highly concentrated compound of n-3 PUFAs as compared to corn oil by measuring thiobarbituric acid–malondialdehyde complex (TBA–MDA) by HPLC. We also studied the influence on TBA–MDA of statins combined with n-3 PUFAs or corn oil.Design: A prospective, randomised, double-blind, controlled study.Setting: One hospital centre in Stavanger, Norway.Subjects: A total of 300 subjects with an acute myocardial infarction (MI).Interventions: Gelatine capsules, containing 850–882 mg EPA and DHA as concentrated ethylesters, or 1 g of corn oil, were ingested in a dose of two capsules twice a day for at least 1 y. Alpha-tocopherol (4 mg) was added to all capsules to protect the PUFAs against oxidation.Results: After 1 y TBA–MDA increased modestly in the n-3 PUFA group (n=125), as compared to the corn oil group (n=130), P=0.027. Multiple linear regression analyses of fatty acids in serum total phospholipids (n=56) on TBA–MDA measured after 12 months intervention, showed no dependency. Performing best subsets regression, serum phospholipid concentration of arachidonic acid (20:4 n-6 PUFA) was identified as a predictor of TBA–MDA at 12 months follow-up, P=0.004.We found no impact of statins on TBA–MDA.Conclusion: TBA–MDA increased modestly after long-term intervention with n-3 PUFAs compared to corn oil post-MI, suggesting biological changes induced by n-3 PUFAs, rather than simply reflecting their concentration differences. The peroxidative potential of n-3 PUFAs was not modified by statin treatment.Sponsorship: Pharmacia A/S and Pronova A/S, Norway.

Nosocomial outbreak of CTX-M-15-producing E. coli in Norway.

Seven E. coli isolates expressing resistance to 3rd generation cephalosporins were recovered from blood (n=2), kidney and lung tissue (n=1), and urinary tract (n=4) samples from seven patients hospitalised or recently discharged from the Divisions of Geriatrics and Pulmonary Medicine, Central Hospital of Rogaland, between July and September 2004. All isolates expressed a typical ESBL‐cefotaximase profile (cefotaxime MIC>ceftazidime MIC) with clavulanic acid synergy. A blaCTX‐M‐15 genotype was confirmed in six strains that were coresistant to gentamicin, nitrofurantoin, trimethoprim‐sulfamethoxazole and ciprofloxacin. A blaCTX‐M‐3 genotype was detected in the last strain. XbaI‐PFGE patterns of the six blaCTX‐M‐15 isolates revealed a clonal relationship. BlaCTX‐M‐15 strains were also positive for the ISEcp1‐like insertion sequences that have been shown to be involved in the mobilization of blaCTX‐M. Further analyses revealed two blaCTX‐M‐15‐positive E. coli urinary isolates clonally related to the outbreak strain from two different patients at the same divisions in January and February 2004. These patients were later re‐hospitalised and one had E. coli with an ESBL‐cefotaximase profile in sputum and nasopharyngeal specimen during the outbreak period. Clinical evaluation suggests that the CTX‐M‐producing E. coli strains contributed to death in three patients due to delayed efficient antimicrobial therapy. The outbreak emphasises the epidemic potential of multiple‐antibiotic‐resistant CTX‐M‐15‐producing E. coli also in a country with low antibiotic usage and low prevalence of antimicrobial resistance.

Low levels of cellular omega-3 increase the risk of ventricular fibrillation during the acute ischaemic phase of a myocardial infarction

AIM OF THE STUDY Animal studies have demonstrated evidence of an anti-arrhythmic effect of marine n-3 fatty acids (FAs). In humans the same mechanism may explain the observed reduction in sudden cardiac death (SCD) associated with intake of fish. Whether high levels of n-3 FAs could protect against ventricular fibrillation (VF) during the acute ischaemic phase of a myocardial infarction (MI) is, however, not known. MATERIALS AND METHODS We measured red blood cell content of eicosapentaenoic acid (EPA)+docosahexaenoic acid (DHA) expressed as a percentage of total FAs (the omega-3 index) at admission in 460 patients hospitalised with an acute coronary syndrome. Out of 265 patients suffering their first MI, 10 (cases) experienced an episode of VF during the initial 6h of symptom onset. The omega-3 index of these patients was compared to that of 185 first-MI patients (controls) free of VF for at least 30 days post-admission. RESULTS The median value of the omega-3 index in the VF cases was 4.88% as compared to 6.08% in the controls (p=0.013). After adjustment for age, sex, ejection fraction, high-sensitivity C-reactive protein, use of beta-blocker, differences of infarct characteristics and previous angina pectoris, a 1% increase of the omega-3 index was associated with a 48% reduction in risk of VF (odds ratio (OR) 0.52, 95% confidence interval (CI) 0.28-0.96; p=0.037). CONCLUSION Our study supports an anti-arrhythmic effect of n-3 FAs through their incorporation into myocardial cell membranes, reducing the risk of VF during ischaemia.

(n-3) Fatty Acid Content of Red Blood Cells Does Not Predict Risk of Future Cardiovascular Events following an Acute Coronary Syndrome

A reduced risk of fatal coronary artery disease has been associated with a high intake of (n-3) fatty acids (FA) and a direct cardioprotective effect by their incorporation into myocardial cells has been suggested. Based on these observations, the omega-3 index (eicosapentaenoic acid + docosahexaenoic acid in cell membranes of RBC expressed as percent of total FA) has been suggested as a new risk marker for cardiac death. In this study, our aim was to evaluate the omega-3 index as a prognostic risk marker following hospitalization with an acute coronary syndrome (ACS). The omega-3 index was measured at admission in 460 patients with an ACS as defined by Troponin-T (TnT) > or = 0.02 microg/L. During a 2-y follow-up, recurrent myocardial infarctions (MI) (defined as TnT > 0.05 microg/L with a typical MI presentation) and cardiac and all-cause mortality were registered. Cox regression analyses were used to relate the risk of new events to the quartiles of the omega-3 index at inclusion. After correction for age, sex, previous heart disease, hypertension, diabetes, smoking, high-sensitivity C-reactive protein, brain natriuretic peptide, creatinine, total cholesterol, HDL-cholesterol, triacylglycerol, homocysteine, BMI, and medication, there was no significant reduction in risk for all-cause mortality, cardiac death, or MI with increasing values of the index. In conclusion, we could not confirm the omega-3 index as a useful prognostic risk marker following an ACS.

Homocysteine‐lowering therapy does not affect inflammatory markers of atherosclerosis in patients with stable coronary artery disease

Objectives.  A high level of total homocysteine (tHcy) is a risk marker for cardiovascular disease (CVD), and is related to inflammation. We wanted to test the effect of homocysteine‐lowering B‐vitamin therapy, as used in the Western Norway B‐vitamin Intervention Trial (WENBIT), on inflammatory markers associated with atherosclerosis.

Long term influence of regular intake of high dose n-3 fatty acids on CD40-ligand, pregnancy-associated plasma protein A and matrix metalloproteinase-9 following acute myocardial infarction

Pregnancy-associated plasma protein A (PAPP-A) and matrix metalloproteinase 9 (MMP-9), both zinc-binding endopeptidases, are abundantly expressed in ruptured and eroded plaques in patients with acute coronary syndromes (ACS). The adhesion molecule CD-40 ligand (CD40L), expressed on activated platelets and T-lymphocytes, can activate metalloproteinases and thereby promote plaque-rupture. N-3 fatty acids, through their anti-inflammatory and anti-thrombotic properties, might reduce the levels of these proatherosclerotic markers and thereby the development of ACS. 300 patients were randomized on day 4 to 6 following an acute myocardial infarction (MI) to receive either 4 g of n-3 fatty acids or a similar daily dose of corn oil for at least one year. We compared levels of PAPP-A, MMP-9 and sCD-40 L at baseline and 12 months in each group, and also looked for inter-group changes. In the omega-3 group, the median level of PAPP-A rose from 0.47 mU/l to 0.56 mU/l (p < 0.001). In the same group, sCD-40 L decreased from a mean baseline value of 5.19 ng/ml to 2.45 ng/ml (p < 0.001) and MMP-9 decreased nonsignificantly from 360.50 ng/ml to 308.00 ng/ml. Corresponding values for the corn oil group were 0.54 mU/l to 0.59 mU/l for PAPP-A (p = 0.007), 5.27 ng/ml to 2.84 ng/ml for sCD-40 L (p < 0.001) and 430.00 ng/ml to 324.00 ng/ml for MMP-9 (p = ns), respectively. In conclusion; both interventions resulted in a significant rise in PAPP-A, a significant decrease in sCD40L and a non-significant decrease in MMP-9 after 12 months of treatment in MI survivors. No inter-group differences were noted.

The long-term prognostic value of multiple biomarkers following a myocardial infarction

INTRODUCTION We assessed the long-term prognostic value of multiple cardiac biomarkers after an acute myocardial infarction (MI) in order to evaluate a multimarker approach to risk stratification. MATERIAL AND METHODS Blood samples from 298 patients hospitalized with a myocardial infarction were subsequently tested for NT-proBNP, hsCRP, MMP-9, PAPP-A, MPO, sCD40L and FM. RESULTS During the median follow-up period of 45 months, 83 patients suffered at least one TnT- positive event. In the unadjusted analysis NT-proBNP predicted future ACS or cardiac death with a hazard ratio (HR) of 1.83 (95% confidence interval (CI), 1.17-2.87, p=0.009) in Q4 as compared to the three lower quartiles (Q1-3). However, NT-proBNP was dependent on chronic heart failure and HDL-cholesterol in the stepwise multivariable model, with a hazard ratio (HR) in Q4 of 1.38 (95% CI, 0.82-2.33, p=0.229). The other biomarkers were not found to be related to the primary event following the index MI. CONCLUSION In a patient population consisting of 298 subjects hospitalized with a MI, a multimarker approach with NT-proBNP, hsCRP, MMP-9, PAPP-A, MPO, sCD40L and FM rendered no additional prognostic information beyond conventionally used stratification tools in the acute phase. However, this does not preclude clinical valuable prognostic information by a biomarker such as NT-proBNP.

The long pentraxin 3 (PTX3): a novel prognostic inflammatory marker for mortality in acute chest pain

The long pentraxin 3 (PTX3) is a recently identified member of the pentraxin protein family that includes C-reactive protein. PTX3 is produced by the major cell types involved in atherosclerotic lesions in response to inflammatory stimuli, and elevated plasma levels are found in several conditions including acute coronary syndromes (ACS). The aim of this study was to assess the value of PTX3 as a prognostic marker of mortality and recurrent ischaemic events in a consecutive series of patients admitted with acute chest pain and potential ACS. The patients received follow-up for 24 months. Blood samples were taken on admission for measurement of PTX3, high sensitive C-reactive protein (hsCRP), B-type natriuretic peptide (BNP), and troponin T. All-cause mortality at 24 months in the study cohort was 15.2%. Patients in the upper PTX3 quartiles had a significantly higher death risk than those in the lowest quartile (Q3: hazard ratio [HR] 2.36; 95% CI 1.12-4.99; p = 0.024, and Q4: HR 3.60; 95% CI 1.68-7.72; p = 0.001). Elevated BNP levels were also significantly associated with a fatal outcome (Q3: HR 3.05; 95% CI 1.16-7.99; p = 0.024; and Q4: HR 3.90; 95% CI 1.48-10.26; p = 0.006). Elevation in hsCRP was not associated with increased death risk. As PTX3 predicted mortality independently of BNP, the combination of these two biomarkers showed an incremental prognostic value. PTX3 is a new biomarker related to inflammation that, independently of BNP, strongly predicts long-term all-cause mortality in patients with acute chest pain. The combination of these two biomarkers enhances the prognostic value over either marker alone.