Evolution of Haptoglobin Concentration in Serum during the Early Phase of Acute Myocardial Infarction

Peer Reviewe

Preinfarction angina protects against out-of-hospital ventricular fibrillation in patients with acute occlusion of the left coronary artery

AbstractOBJECTIVESThe goal of this study was to evaluate the effect of preconditioning on out-of-hospital ventricular fibrillation (VF) in patients with acute myocardial infarction (AMI).BACKGROUNDMore than half of the deaths associated with AMI occur out of the hospital and within 1 h of symptom onset. In humans, preinfarction angina (PA), which can serve as a surrogate marker for preconditioning, reduces infarct size, but the protective effect against out-of-hospital VF has not been investigated.METHODSPreinfarction angina status and acute coronary angiographic findings of 72 consecutive patients with AMI complicated by out-of-hospital VF were compared with 144 matched controls without this complication.RESULTSPreinfarction angina is associated with a lower risk for VF (odds ratio [OR]: 0.40, 95% confidence interval [CI]: 0.18 to 0.88). In patients with acute occlusion of the left coronary artery (LCA) (n = 136), the risk reduction is pronounced (OR: 0.25, 95% CI: 0.10 to 0.66), whereas, in patients with acute occlusion of the right coronary artery (RCA) (n = 67), the protective effect of PA on VF was not observed (OR: 2.25, 95% CI: 0.45 to 11.22). Subgroup and multivariate analyses show that the protective effect is independent of cardiovascular risk factors, preinfarction treatment with beta-adrenergic blocking agents or aspirin, the presence of collaterals or residual antegrade flow or the extent of coronary artery disease.CONCLUSIONSPreinfarction angina protects against out-of-hospital VF in patients with acute occlusion of the LCA. This protection is independent of risk factors or coronary anatomy. A larger study is needed to examine the apparently different effect in patients with acute occlusion of the RCA

PF-4var/CXCL4L1 Predicts Outcome in Stable Coronary Artery Disease Patients with Preserved Left Ventricular Function

Background: Platelet-derived chemokines are implicated in several aspects of vascular biology. However, for the chemokine platelet factor 4 variant (PF-4var/CXCL4L1), released by platelets during thrombosis and with different properties as compared to PF-4/CXCL4, its role in heart disease is not yet studied. We evaluated the determinants and prognostic value of the platelet-derived chemokines PF-4var, PF-4 and RANTES/CCL5 in patients with stable coronary artery disease (CAD). Methodology/Principal Findings: From 205 consecutive patients with stable CAD and preserved left ventricular (LV) function, blood samples were taken at inclusion and were analyzed for PF-4var, RANTES, platelet factor-4 and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Patients were followed (median follow-up 2.5 years) for the combined endpoint of cardiac death, non-fatal acute myocardial infarction, stroke or hospitalization for heart failure. Independent determinants of PF-4var levels (median 10 ng/ml; interquartile range 8-16 ng/ml) were age, gender and circulating platelet number. Patients who experienced cardiac events (n = 20) during follow-up showed lower levels of PF-4var (8.5 [5.3-10] ng/ml versus 12 [8-16] ng/ml, p = 0.033). ROC analysis for events showed an area under the curve (AUC) of 0.82 (95% CI 0.73-0.90, p<0.001) for higher NT-proBNP levels and an AUC of 0.32 (95% CI 0.19-0.45, p = 0.009) for lower PF-4var levels. Cox proportional hazard analysis showed that PF-4var has an independent prognostic value on top of NT-proBNP. Conclusions: We conclude that low PF-4var/CXCL4L1 levels are associated with a poor outcome in patients with stable CAD and preserved LV function. This prognostic value is independent of NT-proBNP levels, suggesting that both neurohormonal and platelet-related factors determine outcome in these patients

Genome-wide analyses identify a role for SLC17A4 and AADAT in thyroid hormone regulation.

Thyroid dysfunction is an important public health problem, which affects 10% of the general population and increases the risk of cardiovascular morbidity and mortality. Many aspects of thyroid hormone regulation have only partly been elucidated, including its transport, metabolism, and genetic determinants. Here we report a large meta-analysis of genome-wide association studies for thyroid function and dysfunction, testing 8 million genetic variants in up to 72,167 individuals. One-hundred-and-nine independent genetic variants are associated with these traits. A genetic risk score, calculated to assess their combined effects on clinical end points, shows significant associations with increased risk of both overt (Graves' disease) and subclinical thyroid disease, as well as clinical complications. By functional follow-up on selected signals, we identify a novel thyroid hormone transporter (SLC17A4) and a metabolizing enzyme (AADAT). Together, these results provide new knowledge about thyroid hormone physiology and disease, opening new possibilities for therapeutic targets

Monitoring of haptoglobin concentration during the early phase of acute myocardial infarction.

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Night-day blood pressure ratio and dipping pattern as predictors of death and cardiovascular events in hypertension

Our objective was to assess the prognostic significance of the night-time dipping pattern and the night-day blood pressure (BP) ratio for mortality and cardiovascular events in hypertensive patients without major cardiovascular disease at baseline. We performed a meta-analysis on individual data of 3468 patients from four prospective studies performed in Europe. Age of the subjects averaged 61 +/- 13 years; 45% were men and 61% were under antihypertensive treatment at the time of ambulatory BP monitoring. The night-day BP ratio and 24-h BP averaged, respectively, 0.907 +/- 0.085/0.866 +/- 0.095 and 138.1 +/- 16.4/82.3 +/- 11.0mmHg. Total follow-up time amounted to 23 164 patient-years. We used multivariable Cox regression analysis to assess the outcome of reverse dippers, non-dippers and extreme dippers vs dippers, and to assess the hazard ratios associated with 1 standard deviation higher night-day BP ratio. In comparison with dippers, and with adjustment for confounders and 24-h BP, the incidence of cardiovascular events was worse in reverse dippers (P <= 0.05), whereas mortality was lower in extreme dippers (P <= 0.01); outcome was similar in non-dippers and dippers. The systolic night-day BP ratio independently predicted all-cause mortality and cardiovascular events (P <= 0.001), which persisted after additional adjustment for 24-h BP (P <= 0.05); appropriate interaction terms indicated that the results were similar in men and women, in younger and older patients and in treated and untreated patients. In conclusion, the dipping pattern and the night-day BP ratio significantly and independently predict mortality and cardiovascular events in hypertensive patients without history of major cardiovascular disease, even after adjustment for 24-h BP