Ivan Simic

NT-proBNP for prognostic and diagnostic evaluation in patients with acute coronary syndromes

BACKGROUND AND AIM N terminal-proB-type natriuretic peptide (NT-proBNP) is synthesised and secreted from the ventricular myocardium. This marker is known to be elevated in patients with acute coronary syndromes (ACS). We evaluated NT-proBNP asa significant diagnostic marker and an important independent predictor of short-term mortality (one month) in patients with ACS. METHODS NT-proBNP and cardiac troponin I (cTI) were assessed in 134 consecutive patients (median age 66 years, 73% male)hospitalised for ACS in a cardiological university department. The patients were classified into ST-elevation ACS (STE-ACS, n = 74) and non-ST-elevation ACS (NSTE-ACS, n = 60) groups based on the ECG findings on admission. Patients with Killip class ≥ II were excluded. RESULTS The serum level of NT-proBNP on admission was significantly higher (p < 0.0005), while there was no difference in cTI serum level in the NSTE-ACS patients compared to STE-ACS patients. There was a significant positive correlation between NT-proBNP and cTI in the NSTE-ACS (r = 0.338, p = 0.008) and STE-ACS (r = 0.441, p < 0.0005) patients. There was a significant difference in NT-proBNP (p < 0.0005) and cTI (p < 0.0005) serum level between ACS patients who died within 30 days or who survived after one month. The increased NT-proBNP level is the strongest predictor of mortality in ACS patients, also NT-proBNP cut-point level of 1,490 pg/mL is a significant independent predictor of mortality. CONCLUSIONS We demonstrated the differences and the correlation in the secretion of NT-proBNP and cTI in patients with STE-ACS vs. NSTE-ACS. Our results provide evidence that NT-proBNP is a significant diagnostic marker and an important independent predictor of short-term mortality in patients with ACS.

Influence of Different β-Blockers on Platelet Aggregation in Patients With Coronary Artery Disease on Dual Antiplatelet Therapy

Introduction: The use of β-blockers in the treatment of patients with coronary heart disease is associated with a decrease in the frequency of angina pectoris and mortality of patients. Due to the severity of the disease and previous cardiovascular interventions, many patients with coronary artery disease (CAD) use dual antiplatelet therapy to achieve greater inhibition of platelet aggregation. The influence of β-blockers on platelet aggregation in patients using antiplatelet therapy is not well understood. Objective: To examine the effect of different β-blockers on platelet aggregation in patients on dual antiplatelet therapy. Methodology: The study included 331 patients who were treated at the Department of Cardiology, Clinical Center Kragujevac during 2011. Patients were divided into 4 groups depending on the type of β-blockers that were used (bisoprolol, nebivolol, metoprolol, and carvedilol). Platelet aggregation was measured using the multiplate analyzer and expressed through the value of adenosine diphosphate (ADP) test (to assess the effect of clopidogrel), ASPI test (to assess the effect of acetyl salicylic acid), TRAP test (to assess baseline platelet aggregation), and the ratio of ADP/TRAP and ASPI/TRAP ASPI/TRAP (ASPI - aranchidonic acid induced aggregation, TRAP - thrombin receptor activating peptide) representing the degree of inhibition of platelet aggregation compared to the basal value. In consideration were taken the representation of demographic, clinical characteristics, laboratory parameters, and cardiovascular medications between the groups. Results: Patients who used nebivolol had a significantly lower value of the ratio of ADP/TRAP (0.39 ± 0.30) compared to patients who used bisoprolol (0.48 ± 0.26; P = .038), and trend toward the lower values of ADP test (328.0 ± 197.3 vs 403.7 ± 213.2; P = .059), while there was no statistically significant difference in values of other laboratory parameters of platelet function between other groups. Conclusion: Patients with CAD on dual antiplatelet therapy who used nebivolol had significantly lower levels of residual ADP-induced platelet aggregation compared to baseline than patients who used bisoprolol.

The influence of bisoprolol dose on ADP-induced platelet aggregability in patients on dual antiplatelet therapy.

PurposeDual antiplatelet therapy is recommended after acute coronary syndrome or after percutaneous coronary intervention with coronary stent implantation. Many of the patients on dual antiplatelet therapy receive &bgr;-blockers; some of them could have antiaggregatory effect. Bisoprolol is a highly selective adrenoceptor-blocker, which is often used in the settings of percutaneous coronary intervention or acute coronary syndrome in patients on dual antiplatelet therapy. Its antiaggregative effect has not been extensively studied. Therefore, the aim of this study is to investigate the effect of bisoprolol on ADP-induced platelet aggregation in patients on dual antiplatelet therapy. MethodsPlatelet aggregability has been measured in 100 patients on dual antiplatelet therapy with multiplate analyzer using ADP test in blood samples anticoagulated with heparin. ADP test values have been expressed by arbitrary units/minute. In univariate and multivariate regression analyses, we have investigated the influence of bisoprolol and its dose and also different factors, such as risk factors, concomitant drugs and their dosage, laboratory findings, on ADP test values. ResultsUnivariate regression analysis showed significant correlation between the bisoprolol dose and the ADP test value (P=0.046, B=52.55, 95% confidence interval 0.87–104.23), which was also shown in the multivariate regression analysis (P=0.018; B=57.011; 95% confidence interval 10.455–103.567). ConclusionWe have identified a positive correlation between bisoprolol dose and ADP-induced platelet aggregability in patients on dual antiplatelet therapy.

„Obesity Paradox“ – Fiction or a Fact?

Abstract Background: Many cardiovascular diseases are associated with obesity, but, despite this fact, obese people live longer than their normal-weight counterparts do. This phenomenon is called the „obesity paradox“. Aim: Purpose was to investigate the impact of obesity on the final outcome; determine the connection between obesity and heart rate > 80 beats per minute and other risk factors, and presence of „obesity paradox“. Material and Methods: Research included 140 patients with anterior wall acute STEMI treated in Coronary Unit, Clinical Center Kragujevac form January 2001-June 2006. Heart rate was calculated as the mean value of baseline and heart rate in the first 30 minutes after admission. Body mass index was calculated as the ratio of body weight in kilograms and body height in squared meters, and classified according to the WHO recomendations. Results: More than 75% obese patients were in both groups, survivors and those who died. In the subgroup with heart rate > 80 results were similar. Obesity had no significant effect on mortality despite the fact that the large number of patients with fatal outcome was obese. Conclusion: Correlation with acute myocardial infarction and elevated heart rate is evident, but obesity was not independent predictor for mortality which can only partly confirm presence of „obesity paradox“.

Can Statins Help „Good Cholesterol“ to Become Even Better

Abstract Background: Ischemic heart disease (IHD) is a most common manifestation of generalised atherosclerosis. Hyperlipidemia is one of the most significant risk factors causing atherosclerosis. Becouse of this, statin therapy is the (guideline) in therapy of hyperlipoproteinemia. Aim: The aim of this study was to show the hypolipemic effect of statins. Material and Methods: The research included 74 patients with hyperlipoproteinemia type II and III, with (59 patients) or without (15) coronary disease diagnosis. All patients have been treated with statins. In all patients, we analizing statins hypolipemic effects, and the research was carried out: before therapy, after 2 and 6 weeks, 3 months, and than every 3 months during 2 years of treatment. Results: Target value of lipoprotein profile parameter is achieved after 3-6 months of statin treatment. According to the results HDL-cholesterol was changed with the statins for 12.5% average; the highest average value change of 27.5% was recorded at the end of follow-up, and the minimal mean change, observed 2 weeks after therapy initiation was 4.59%. Conclusion: The statin therapy has significant effect on lipoprotein profile and atherogenic index. That effect is the most intensive after 3 month therapy, and target level of lipoprotein parameter are achieved after 3-6 months of statin treatment.

Fractional Flow Reserve Method in Cardiac Catheterization Laboratory without Cardiosurgical Backup: Initial Experiences

Abstract Background: Coronary artery disease is the most common cause of death in a modern world. This dictates the development a network of Catheterization laboratories without cardiosurgical capabilities. Aim: We postulate that the most valuable tool in the decision process on myocardial revascularization is fractional flow reserve (FFR), especially when we deal with borderline coronary lesions. Material and Methods: A total of 72 patients with 94 intermediate coronary stenosis (30%-70% diameter reduction) were included in this study. We tested FFR and angiography based decision model on myocardial revascularization. Results: Mean FFR value on left anterior descending coronary artery (LAD) was lower than in others two arteries (p=0.017). FFR after percutaneous coronary intervention (PCI) was significantly better (p<0.0001). The decision for PCI predominates before FFR diagnostics, but after FFR the decision is quite opposite. There is a weak negative correlation between FFR and diameter of stenosis assessed by angiography (r= - 0.245 p=0.038) and positive correlation between diameter of stenosis assessed by angiography and by quantitative coronary angiography (QCA) (r=0.406 p<0.0005). Conclusion: Our results strongly suggest that FFR is necessary tool in centers without possibilities of heart team onsite consultation and that prevents numerous unnecessary PCI.