Volker Pönitz

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.

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.

Moderate alcohol consumption is associated with reduced long-term cardiovascular risk in patients following a complicated acute myocardial infarction

BACKGROUND The impact on prognosis of alcohol use in patients with coronary artery disease remains uncertain. We related alcohol use to all-cause mortality, cardiovascular (CV)-mortality and hospitalization in patients following a complicated myocardial infarction (MI). METHODS In the OPTIMAAL trial, 5477 patients from 7 Western European countries with heart failure and/or evidence of left ventricular dysfunction following MI were recruited. Following randomization median 3 days, patients were asked to assess their average alcohol consumption prior to the index infarction. Patients were stratified by the frequency of the use of alcohol into either non-users (n = 2160), moderate users (1-7 drinks/week, n = 2753) and heavy users (> 7 drinks/week, n = 545) and related to prespecified clinical outcomes in the groups. RESULTS A total of 5477 patients were included in the trial. During the follow-up period of 2.7 years 946 deaths were reported. Adjusted for age and smoking status, patients with moderate use of alcohol had 24% lower risk of all-cause death (p < 0.001), 26% lower risk of CV-death (p < 0.000) and 8% lower risk for hospitalization (p = 0.030) than abstainers. There was no significant difference between non-drinkers and heavy drinkers with regard to survival following adjustment for age and smoking status. CONCLUSION Our results demonstrate a strong positive association between moderate alcohol use and survival in a cohort of patients following complicated MI. Both heavy drinkers and abstainers had poorer prognosis, with no significance difference between those 2 groups.

Activated factor XII type A predicts long-term mortality in patients admitted with chest pain.

Summary.  Background: We assessed the relation between admission levels of activated factor XII type A (XIIaA), and long‐term all‐cause and cardiac mortality and recurrent troponin T (TnT) positive cardiovascular events in a consecutive cohort of 870 patients admitted with a clinically strongly suspected acute coronary syndrome (ACS). Methods and results: After a 24‐month follow‐up period, 138 patients (15.8%) had died and 155 (17.8%) had suffered from a recurrent TnT positive (TnT > 0.05 ng mL−1) event. XIIaA levels were significantly lower in long‐term survivors than in patients who died (22.9 (17.7–32.1) vs. 27.2 (20.0–39.7) pmol L−1 [median, 25 and 75% percentiles], P < 0.001). The unadjusted hazard ratio for death within 2 years in patients with XIIaA in the highest quartile was 2.49 (95% confidence interval (CI), 1.52–4.06) as compared with patients with XIIaA in the lowest quartile. In a stepwise Cox regression model for death within 2 years, XIIaA added prognostic information for all‐cause mortality (HR 2.05; 95% CI, 1.21–3.47) above and beyond age, a history of heart failure, ST‐segment elevation, TnT and B‐type natriuretic peptide (BNP). In the subgroup of patients with an admission TnT ≤ 0.05 ng mL−1, XIIaA provided independent prognostic information for all‐cause mortality (HR 3.88; 95% CI, 1.66–9.08) and for the combined endpoint of death or recurrent TnT positive event (HR 2.46; 95% CI, 1.34–4.50). Conclusion: XIIaA, a recently identified in vivo form of activated factor XII is an independent indicator of long‐term all‐cause mortality in patients admitted with chest pain, providing prognostic information above and beyond conventional risk factors.

B-type natriuretic peptide is a long-term predictor of all-cause mortality, whereas high-sensitive C-reactive protein predicts recurrent short-term troponin T positive cardiac events in chest pain patients: a prognostic study

BackgroundFew studies have addressed whether the combined use of B-type natriuretic peptide (BNP) and high-sensitive C-reactive protein (hsCRP) improves risk stratification for mortality and cardiovascular events in a population with chest pain and suspected acute coronary syndromes (ACS). Therefore, we wanted to assess the incremental prognostic value of these biomarkers with respect to long-term all-cause mortality and recurrent troponin T (TnT) positive cardiac events in 871 patients admitted to the emergency department.MethodsBlood samples were obtained immediately following admission.ResultsAfter a follow-up period of 24 months, 129 patients had died. The BNP levels were significantly higher among patients dying than in long-term survivors (401 (145–736) versus 75 (29–235) pq/mL [median, 25 and 75% percentiles], p = 0.000). In a multivariable Cox regression model for death within 2 years, the hazard ratio (HR) for BNP in the highest quartile (Q4) was 5.13 (95% confidence interval (CI), 1.97–13.38) compared to the lowest quartile (Q1) and was associated with all-cause mortality above and beyond age, congestive heart failure and the index diagnosis ST-segment elevation myocardial infarction. HsCRP rendered no prognostic information for all-cause mortality. However, within 30 days, the adjusted HR for patients with recurrent TnT cardiac positive events hsCRP in Q4 was 14.79 (95% CI, 1.89–115.63) compared with Q1 and was associated with recurrent ischemic events above and beyond age, hypercholesterolemia and TnT values at admission.ConclusionBNP may act as a clinically useful biomarker when obtained at admission in an unselected patient population following hospitalization with chest pain and potential ACS, and may provide complementary prognostic information to established risk determinants at long-term follow-up. Our data do not support the hypothesis that the additional assessment of hsCRP will lead to better risk stratification for survival than BNP alone.Trial registrationNCT00521976

The prognostic utility of D-dimer and fibrin monomer at long-term follow-up after hospitalization with coronary chest pain.

D-dimer and fibrin monomer both reflect a prothrombotic potential. There are limited data available comparing these two markers of activated coagulation in a prospective manner in an unselected patient population presenting to the emergency department with chest pain. In addition, their role in risk stratification in patients with acute coronary syndrome is still under evaluation. Therefore, we wanted to assess the prognostic value of these markers with respect to long-term all-cause mortality in 871 patients admitted to the emergency department. Blood samples were obtained immediately following admission. After a follow-up period of 24 months, 123 patients had died. In the univariate analysis, both D-dimer and fibrin monomer predicted all-cause mortality within 2 years with an odds ratio of 7.78 (95% confidence interval, 3.95–15.33) and 4.19 (95% confidence interval, 2.42–7.28), respectively, in the highest quartile (Q4) compared with the lowest quartile (Q1). However, in the multivariable logistic regression model for death within 2 years, the odds ratio of D-dimer and fibrin monomer was 1.80 (95% confidence interval, 0.81 to 3.97) and 1.04 (95% confidence interval, 0.53 to 2.04) in Q4 compared with Q1, respectively, and added no prognostic information above and beyond age, known coronary heart disease, B-type natriuretic peptide and the index diagnoses of ST-segment elevation myocardial infarction, non-ST-segment elevation myocardial infarction and unstable angina pectoris. In an unselected patient population hospitalized with chest pain and potential acute coronary syndrome, neither D-dimer nor fibrin monomer provided complementary prognostic information to established risk determinants during long-term follow-up.

Prognostic Utility of Vitamin D in Acute Coronary Syndrome Patients in Coastal Norway

Background. An inverse relationship between cardiovascular risk and levels of vitamin D and omega-3 index may exist. Objectives. To evaluate the prognostic utility of serum 25-hydroxyvitamin D [25(OH)D] in 871 patients with suspected acute coronary syndrome (ACS) and to assess the seasonal correlation between 25(OH)D and the omega-3 index in 456 ACS patients from southwestern Norway. Results. In the univariate analysis the hazard ratio (HR) at 2-year follow-up for all-cause mortality in the highest as compared to the lowest quartile of 25(OH)D in the total population was 0.61 (95% confidence interval (CI), 0.37–1.00), P = 0.050. At 7-year follow-up, the corresponding HR for all-cause mortality was 0.66 (95% CI, 0.49–0.90), P = 0.008, and for females alone 0.51 (95% CI, 0.32–0.83), P = 0.006. Quartile survival did not differ in the multivariable analysis, whereas 25(OH)D < 40 nM (<16 ng/mL) was found to be independently related to mortality. Seasonal differences in 25(OH)D, but not for the omega-3 index, were noted, and the two biomarkers were positively correlated, especially during winter-spring; Pearsons correlation coefficient was 0.358, P < 0.001. Conclusion. Vitamin D levels are related to survival, especially in females, and correlate with the omega-3 index.

The prognostic utility of dihomo-gamma-linolenic acid (DGLA) in patients with acute coronary heart disease

BACKGROUND We previously investigated the prognostic utility of red blood cell (RBC) n-3 fatty acids (FAs) in survivors of an acute myocardial syndrome (ACS) but found no relationship with all-cause mortality and cardiac death or MI after two years. Here we extend our follow-up to 7years, focusing on the potential predictive power of RBC n-6 FAs. METHODS We included 398 ACS patients presenting with increased troponin-T (TnT) levels for whom baseline RBC FA data were available. Cox regression analysis was used to relate the risk of future events to RBC n-6 FA levels, both continuously and by quartile. RESULTS At 7-year follow-up, 183 (46.0%) had died, 128 (32.2%) had experienced another MI and 24 (6.0%) had had a stroke. Death or MI occurred in 227 patients (57.0%); and death, MI or stroke in 235 patients (59.0%). In a multivariable Cox regression model for total death, the hazard ratio (HR) in the highest as compared to the lowest quartile of dihomo-γ-linolenic acid (DGLA) was 0.55 [95% confidence interval (CI), 0.35-0.88, p=0.012, for death or MI [HR 0.62 (95% CI, 0.41-0.94), p=0.025], and for the fully combined endpoint [HR 0.57 (95% CI, 0.38-0.86), p=0.006]. Similar results were found in the per 1-SD analysis. No other RBC n-6 FAs significantly predicted these outcomes in multivariable models. CONCLUSION RBC DGLA levels had significant independent prognostic value in post-ACS patients. These findings need confirmation, and the possible biochemical pathways by which higher DGLA membrane levels may be cardioprotective should be explored.

A history of late and very late stent thrombosis is not associated with increased activation of the contact system, a case control study

BackgroundThe pathophysiological pathways resulting in Late Stent Thrombosis (LST) remain uncertain. Findings from animal studies indicate a role of the intrinsic coagulation pathway in arterial thrombus formation, while clinical studies support an association with ischemic cardiovascular disease. It is currently unknown whether differences in the state of the contact system might contribute to the risk of LST or Very Late Stent Thrombosis (VLST). We assessed the relation between levels of several components involved in the contact system and a history of LST and VLST, termed (V)LST in a cohort of 20 patients as compared to a matched control group treated with PCI.Methods and ResultsActivated factor XII (FXIIa), FXII zymogen (FXII), FXIIa-C1-esterase inhibitor (C1-inhibitor), Kallikrein-C1-inhibitor, FXIa-C1-inhibitor and FXIa-α1-antitrypsin (AT-inhibitor) complexes were measured by Enzyme-linked immunosorbent assy (ELISA) methodology.Cases and controls showed similar distributions in sex, age, baseline medications and stent type. Patients with a history of (V)LST had a significantly greater stent burden and a higher number of previous myocardial infarctions than the control patients.There were no significant between-group differences in the plasma levels of the components of the contact system.ConclusionIn a cohort of patients with a history of (V)LST, we did not observe differences in the activation state of the intrinsic coagulation system as compared to patients with a history of percutaneous coronary intervention without stent thrombosis.