Release pattern of N-terminal pro B-type natriuretic peptide (NT-proBNP) in acute coronary syndromes

Timing of SGLT2i initiation after acute myocardial infarction

BACKGROUND

Pharmacological post-MI treatment is routinely initiated at intensive/cardiac care units. However, solid evidence for an early start of these therapies is only available for dual platelet therapy and statins, whereas data on beta blockers and RAAS inhibitors are heterogenous and mainly limited to STEMI and heart failure patients. Recently, the EMMY trial provided the first evidence on the beneficial effects of SGLT2 inhibitors (SGLT2i) when initiated early after PCI. In patients with type 2 diabetes mellitus, SGLT2i are considered "sick days drugs" and it, therefore, remains unclear if very early SGLT2i initiation following MI is as safe and effective as delayed initiation.

METHODS AND RESULTS

The EMMY trial evaluated the effect of empagliflozin on NT-proBNP and functional and structural measurements. Within the Empagliflozin group, 22 (9.5%) received early treatment (< 24 h after PCI), 98 (42.2%) within a 24 to < 48 h window (intermediate), and 111 (48.1%) between 48 and 72 h (late). NT-proBNP levels declined by 63.5% (95%CI: - 69.1; - 48.1) in the early group compared to 61.0% (- 76.0; - 41.4) in the intermediate and 61.9% (- 70.8; - 45.7) in the late group (n.s.) within the Empagliflozin group with no significant treatment groups-initiation time interaction (pint = 0.96). Secondary endpoints of left ventricular function (LV-EF, e/e`) as well as structure (LVESD and LVEDD) were also comparable between the groups. No significant difference in severe adverse event rate between the initiation time groups was detected.

CONCLUSION

Very early administration of SGLT2i after acute myocardial infarction does not show disadvantageous signals with respect to safety and appears to be as effective in reducing NT-proBNP as well as improving structural and functional LV markers as initiation after 2-3 days.

Recent advancements of nanomodified electrodes - Towards point-of-care detection of cardiac biomarkers

The increasing number of deaths from cardiovascular diseases has become a substantial concern in both developed and underdeveloped countries. Rapid and on-site monitoring of this disease is urgently important to control, prevent and make awareness of public health. Recently, a lot of focus has been placed on nanomaterials and modify these nanomaterials have been explored to detect cardiac biomarkers. By implementing biosensors that are modified with novel recognition elements and more stable nanomaterials, the use of electrochemistry for point-of-care devices is more realistic every day. This review focuses on the current state of nanomaterials conjugated biorecognition elements (enzyme integrated with nanomaterials, antibody conjugated nanomaterials and aptamer conjugated nanomaterials) for electrochemical cardiovascular disease detection. Specifically, a lot of attention has been given to the trends toward more stable biosensors that have increased the potential to be used as point-of-care devices for the detection of cardiac biomarkers due to their high stability and specificity. Moreover, the recent progress on biomolecule-free electrochemical nanosensors for cardiovascular disease detection has been considered. At last, the possibility and drawbacks of some of these techniques for point-of-care cardiac device development in the future have been discussed.

Serum Biomarkers for the Detection of Cardiac Dysfunction in Childhood Cancers Receiving Anthracycline-Based Treatment

Anthracyclines are routinely used in cancer chemotherapy in many childhood cancers. A serious adverse effect of doxorubicin chemotherapy is cardiotoxicity which may lead to congestive heart failure for long-term survivors years after treatment. Currently, echocardiography is used to control the heart function during anthracyclines therapy. B-type natriuretic peptide (BNP) and NT-proBNP as well as cardiac troponins have been proposed as clinical markers for subclinical anthracycline-induced cardiotoxicity. The BNP and pro-BNP can be easily measured in plasma and initial data indicate that the NT-proBNP could be sensitive predictor for the development of congestive heart failure.

Potential pitfalls when interpreting plasma BNP levels in heart failure practice

B-type (or brain) natriuretic peptide (BNP) is synthesized in cardiac myocytes and released constitutively into the circulation. Pressure/volume overload, neurohumoral factors, cytokines, and ischemia enhance BNP gene expression, and then precursor proBNP is produced. It has been thought that proBNP is cleaved into active BNP molecule and inactive marker molecule NT-proBNP intracellularly by processing enzyme furin, and they are released into the circulation. However, recent studies have shown that considerable amount of uncleaved proBNP circulates in the blood. The commercially available BNP assay kits consist of two antibodies that sandwich the BNP molecule. Therefore, if proBNP is present, BNP assay kit cross-reacts to proBNP and measures it as BNP. Therefore, it should be noted that the current BNP value is proBNP plus BNP. BNP and NT-proBNP have been established as a biomarker for heart failure patients presenting dyspnea. But many pitfalls are present for interpreting the BNP value. For example, the presence of renal dysfunction, age, female sex, atrial fibrillation, inflammation, hyperthyroidism, use of sacubitril/valsartan, and macro-proBNPemia overestimate BNP value, whereas the presence of obesity, immediately after acute coronary syndrome onset, and pericardial effusion underestimate BNP value. In the management for heart failure patients, BNP plays an important role. Therefore, clinicians should note the pitfall of interpretation of BNP and we describe the mechanism involved.

Do N-terminal pro-brain natriuretic peptide levels determine the prognosis of community acquired pneumonia?

OBJECTIVE

Pneumonia is a leading cause of mortality worldwide, especially in the elderly. The use of clinical risk scores to determine prognosis is complex and therefore leads to errors in clinical practice. Pneumonia can cause increases in the levels of cardiac biomarkers such as N-terminal pro-brain natriuretic peptide (NT-proBNP). The prognostic role of the NT-proBNP level in community acquired pneumonia (CAP) remains unclear. The aim of this study was to evaluate the prognostic role of the NT-proBNP level in patients with CAP, as well as its correlation with clinical risk scores.

METHODS

Consecutive inpatients with CAP were enrolled in the study. At hospital admission, venous blood samples were collected for the evaluation of NT-proBNP levels. The Pneumonia Severity Index (PSI) and the Confusion, Urea, Respiratory rate, Blood pressure, and age ≥ 65 years (CURB-65) score were calculated. The primary outcome of interest was all-cause mortality within the first 30 days after hospital admission, and a secondary outcome was ICU admission.

RESULTS

The NT-proBNP level was one of the best predictors of 30-day mortality, with an area under the curve (AUC) of 0.735 (95% CI: 0.642-0.828; p < 0.001), as was the PSI, which had an AUC of 0.739 (95% CI: 0.634-0.843; p < 0.001), whereas the CURB-65 had an AUC of only 0.659 (95% CI: 0.556-0.763; p = 0.006). The NT-proBNP cut-off level found to be the best predictor of ICU admission and 30-day mortality was 1,434.5 pg/mL.

CONCLUSIONS

The NT-proBNP level appears to be a good predictor of ICU admission and 30-day mortality among inpatients with CAP, with a predictive value for mortality comparable to that of the PSI and better than that of the CURB-65 score.

Ramipril and Losartan Exert a Similar Long-Term Effect upon Markers of Heart Failure, Endogenous Fibrinolysis, and Platelet Aggregation in Survivors of ST-Elevation Myocardial Infarction: A Single Centre Randomized Trial

Introduction. Blocking the renin-angiotensin-aldosterone system in ST-elevation myocardial infarction (STEMI) patients prevents heart failure and recurrent thrombosis. Our aim was to compare the effects of ramipril and losartan upon the markers of heart failure, endogenous fibrinolysis, and platelet aggregation in STEMI patients over the long term. Methods. After primary percutaneous coronary intervention (PPCI), 28 STEMI patients were randomly assigned ramipril and 27 losartan, receiving therapy for six months with dual antiplatelet therapy (DAPT). We measured N-terminal proBNP (NT-proBNP), ejection fraction (EF), plasminogen-activator-inhibitor type 1 (PAI-1), and platelet aggregation by closure times (CT) at the baseline and after six months. Results. Baseline NT-proBNP ≥ 200 pmol/mL was observed in 48.1% of the patients, EF < 55% in 49.1%, and PAI-1 ≥ 3.5 U/mL in 32.7%. Six-month treatment with ramipril or losartan resulted in a similar effect upon PAI-1, NT-proBNP, EF, and CT levels in survivors of STEMI, but in comparison to control group, receiving DAPT alone, ramipril or losartan treatment with DAPT significantly increased mean CT (226.7 ± 80.3 sec versus 158.1 ± 80.3 sec, p < 0.05). Conclusions. Ramipril and losartan exert a similar effect upon markers of heart failure and endogenous fibrinolysis, and, with DAPT, a more efficient antiplatelet effect in long term than DAPT alone.

Natriuretic peptides, nitrite/nitrate and superoxide dismutase have additional value on top of the GRACE score in prediction of one-year mortality and rehospitalisation for heart failure in STEMI patients - Multiple biomarkers prospective cohort study

BACKGROUND

Blood-based biomarkers have a prognostic value in patients with myocardial infarction. The aim of our prospective observational cohort study was to evaluate the prognostic value of biomarkers of different pathophysiological pathways for the occurrence of 1-year all-cause mortality and hospitalisation due to acute heart failure.

METHODS AND RESULTS

In 593 patients with ST-segment elevation MI (STEMI) treated by primary PCI, biomarkers were evaluated at 24h after MI onset. A minimum of three-year follow-up was achieved in all patients. The combination of 1-year all-cause mortality and hospitalisation due to heart failure was the primary endpoint. A cohort for validation of our combined GRACE-natriuretic peptide (NP) score included 667 STEMI patients. The primary endpoint was reached in 9.3% of patients. Among 21 biomarkers, only B-type natriuretic peptide (BNP), NT-proBNP, superoxide dismutase and nitrite/nitrate, added to clinical GRACE score led to a significant increase in the area under the curve of C statistics, in comparison to GRACE alone (tested by Delong's test). Continuous net reclassification improvement and integrated discrimination index demonstrated an improved reclassification and discrimination of the GRACE model for SOD, BNP and NT-proBNP, and improved reclassification for nitrite/nitrate. Consistent results for this new combined prognostic model GRACE-NP were found also for a validation cohort.

CONCLUSIONS

The levels of NP have an additional value to the prognostic properties of the GRACE score for the prediction of the combined endpoint of one-year mortality or hospitalisation for AHF. Nitrite/nitrate and SOD are strong prognostic factors, even on top of the GRACE score.

Anthracycline or trastuzumab-related cardiotoxicity: do we have a predictive biomarker?

Chemotherapy-induced cardiotoxicity, is a well-known and potentially serious complication strongly impacting the quality of life and overall survival of breast cancer patients. The current diagnostic approach to detect cardiac damage is the estimation of left ventricular ejection fraction by echocardiography. However, this approach exhibits less sensitivity toward early prediction of cardiomyopathy, not allowing for preventive strategies. Measurement of serum cardiac-specific biomarkers can be a valid diagnostic tool for identifying patients prone to developing cardiotoxocity and in whom closer cardiac monitoring and preventive strategies are pivotal. In this article, we review work done on biomarkers in recent years, with an emphasis on troponin and B-type natriuretic peptide, which are currently the most studied in this field. We also briefly discuss current and emerging imaging techniques for early detection of cardiomyopathy.

Prognostic role of troponin and natriuretic peptides as biomarkers for deterioration of left ventricular ejection fraction after chemotherapy

Cardiotoxicity due to anthracyclines, trastuzumab and other potential cardiotoxic drugs is still a problem of modern chemotherapy. For years researchers have tried to find biological markers that can predict changes in the heart. The most thoroughly tested markers are troponin and natriuretic peptides. Some studies have proven that these markers can indeed be useful. In studies which have shown the predictive role of troponin I the assessment of this marker was performed very frequently. It is not possible to carry out such serial measurements in many centers because of typical 1-day hospital stay times. The predictive role of natriuretic peptides still needs further investigation. This review considers the newest research from recent years.

N-Terminal Pro-Brain Natriuretic Peptide Level is Associated With Severity and Complexity of Coronary Atherosclerosis in Patients With Acute Coronary Syndrome

N-terminal pro-brain natriuretic peptide (NT-proBNP) levels are associated with short- and long-term mortality in acute coronary syndrome (ACS). We investigated whether baseline NT-proBNP levels are associated with burden of coronary atherosclerosis assessed by SYNTAX score (SXScore). We enrolled 509 patients with ACS who underwent coronary angiography. The patients were divided into tertiles according to the SXScore: low SXScore (≤ 22), intermediate SXScore (23-32), and high SXScore (≥ 33). The NT-proBNP levels demonstrated an increase from low SXScore tertile to high SXScore tertile. The NT-proBNP levels according to the SXScore tertiles are as follows: low and intermediate (median 635 vs 1635, P = .014), low and high (median 635 vs 4568, P < .001), and intermediate and high (median 1635 vs 4568, P < .001). In multivariate analysis, NT-proBNP remained an independent predictor of high SXScore (odds ratio: 2.688, 95% confidence interval: 1.315-5.494, P = .007) together with age (P = .002), neutrophil-lymphocyte ratio (P = .017), and presence of non-ST-segment elevation ACS (P = .002). The NT-proBNP was independently associated with burden of coronary atherosclerosis in patients with ACS.

Myocardial performance index and biochemical markers for early detection of doxorubicin-induced cardiotoxicity in children with acute lymphoblastic leukaemia

BACKGROUND

Despite significant improvements in the prognosis of childhood acute lymphoblastic leukaemia (ALL), the risk of anthracycline-induced cardiovascular disease remains a major concern. This study was designed to investigate the role of the myocardial performance index (MPI) and serum concentrations of biomarkers (cTnT and NT-pro-BNP) in the early detection of subclinical anthracycline-induced functional alterations in children with ALL.

METHODS

All children consecutively admitted to our Pediatric Oncologic Department from January 2009 to October 2010 with a diagnosis of ALL were enrolled in this study. cTnT and NT-pro-BNP were evaluated in all patients at diagnosis, before doxorubicin therapy and 2 and 24 h following each anthracycline administration. ECG and echocardiography were performed at diagnosis and 24 h after each anthracycline course.

RESULTS

Nineteen children with standard-risk ALL were evaluated. The mean age was 6 years. The cumulative doxorubicin dosage was 240 mg/m(2) according to the AIEOP (Associazione Italiana Ematologia Oncologia Pediatrica) ALL 2000 protocol. None of the 19 patients developed congestive heart failure. With increasing cumulative dosages of anthracyclines a significant increase was observed in MPI. This increase was statistically significant starting from the cumulative dosage of 120 mg/m(2) compared to baseline, while the median NT-pro-BNP level did not change significantly during treatment and cTnT levels never exceeded the cut-off value for cardiac injury.

CONCLUSION

MPI value is a sensitive and accurate parameter, allowing subclinical cardiac dysfunction to be detected in children receiving anthracyclines. Lifelong cardiac surveillance of these patients is warranted in order to determine the clinical implications of increased MPI on long-term cardiac status.

Established and novel biomarkers in ST-elevation myocardial infarction

Cardiac biomarkers assist in the diagnosis of and risk stratification in acute coronary syndromes. In ST-elevation myocardial infarction (STEMI), rapid diagnosis and initiation of reperfusion via primary percutaneous coronary intervention or fibrinolysis is often based on the clinical history and presenting ECG, but measurement of biomarkers in the early and/or late phases of STEMI may allow the selection of patients who are at increased or decreased risk of subsequent complications. Although the measurement of only three biomarkers (troponin, natriuretic peptides and C-reactive protein) are currently included in practice guidelines, more than 20 other novel cardiac biomarkers have been proposed to provide improved risk stratification after a STEMI.

Fluorouracil Induces Myocardial Ischemia With Increases of Plasma Brain Natriuretic Peptide and Lactic Acid but Without Dysfunction of Left Ventricle

Purpose

Fluorouracil (FU) is a cornerstone of colorectal cancer treatment; however, it has clinical and subclinical influence on the heart. This study aimed to clarify the pathophysiology, risk factors, and long-term effects of FU cardiotoxicity.

Patients and Methods

The study prospectively accrued colorectal cancer patients (n = 106) completely resected and adjuvantly treated with FU and oxaliplatin according to the FOLFOX4 regimen (infusional FU, folinic acid, and oxaliplatin). Serial measurements were made of systolic and diastolic features of the left ventricle by radionuclide ventriculography, plasma levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), lactic acid, and ECG before chemotherapy, immediately after a treatment infusion, and at follow-up 2 weeks after cessation of the intended 12 treatment courses and were further evaluated by multivariate regression analysis that included cardiovascular history and its risk factors.

Results

In the entire cohort, NT-proBNP significantly increased from baseline 14.5 ± 3.2 pmol/L (mean ± standard error) to 28.3 ± 5.3 pmol/L during FU therapy (P < .001). Nine patients (8.5%) with cardiotoxicity had significantly higher NT-proBNP of 55.3 ± 40.8 pmol/L compared with 25.4 ± 4.1 pmol/L in those without (P < .001). In multivariate analysis, the FU-induced rise of NT-proBNP was significantly higher in females (P < .001). Plasma lactic acid significantly increased from baseline (1.3 ± 0.1 mmol/L to 1.8 ± 0.1 mmol/L) during FU therapy (P < .001). Left ventricular ejection fraction at baseline of 0.66 ± 0.01 remained unchanged at 0.65 ± 0.01 during FU therapy and 0.66 ± 0.01 at follow-up (P = .4).

Conclusion

FU therapy generally induces myocardial neuroendocrine changes with increasing plasma NT-proBNP and lactic acid but without long-term dysfunction of the left ventricle. The usability of NT-proBNP as a predictive marker for FU cardiotoxicity remains to be clarified.

Plasma urocortin in acute myocardial infarction patients

BACKGROUND

Despite its proposed cardioprotective effect, the role of plasma urocortin in acute myocardial infarction (AMI) remains unknown. We investigated plasma profile of urocortin in AMI patients and evaluated its long-term prognostic performance.

MATERIAL AND METHODS

Sixty-six AMI patients and 21 healthy subjects were included in this study. Blood samples for urocortin were collected on days 0 (onset), 1, 3 and 5 and at 3 and 6 months. Primary endpoint was mortality within 1 year of follow-up. Secondary endpoint was combined death and nonfatal adverse cardiac events (i.e. myocardial reinfarction, urgent revascularization or hospitalization due to heart failure) within 1 year.

RESULTS

During follow-up at 1 year, 38 (57·6%) patients were alive without cardiac events, nine (13·6%) had nonfatal cardiac events and 17 (25·8%) died. Plasma urocortin in AMI patients were increased on days 0, 1, 3 and 5 (P<0·05 vs. control). The receiver-operating characteristic curve showed an area under curve (AUC) of day 0 urocortin to be 0·750 with 95% confidence interval (CI) of 0·619-0·881 (P=0·004), whereas AUC of NT-proBNP was 0·857 (95% CI, 0·722-0·992; P=0·003). Sensitivity values for predicting the mortality of urocortin NT-proBNP and a combined urocortin and NT-proBNP were 0·81 (95% CI, 0·54-0·95), 0·86 (95% CI, 0·42-0·99) and 1·0 (95% CI, 0·56-1·0), respectively.

CONCLUSIONS

Plasma urocortin level is elevated in AMI patients for 5 days from onset. High plasma urocortin within 24 h after the onset is associated with increased mortality. Combined urocortin and NT-proBNP enhance prognostic performance in AMI patients.

Ischemia triggers BNP expression in the human myocardium independent from mechanical stress

BACKGROUND

It is unknown whether the increased B-type natriuretic peptide (BNP) values found in ischemic heart disease are triggered directly by ischemia or whether they are caused indirectly by ischemia through diastolic contractures or regional wall motion abnormalities. Therefore, we investigated the BNP expression in isolated human muscle strips under conditions of ischemia with and without mechanical stress.

METHODS

Muscle strips (n=90) were isolated from human right atria (n=46). Contractures were induced by oxygen and glucose withdrawal. In 18 muscle strips contractures were prevented by means of butanedione monoxime (BDM). Sarcomere lengths were measured by electron microscopy (n=12). The gene expression and protein amount of BNP were determined and compared to control muscle strips contracting under physiological conditions.

RESULTS

Hypoxia significantly decreased systolic force and induced diastolic contractures. This mechanical stress could be prevented in the group treated with BDM as evidenced by electron microscopy. Ischemia significantly increased BNP expression in both groups as evidenced by Northern blot analysis and immunohistochemistry. This increase was independent from mechanical stress.

CONCLUSION

Our results indicate that ischemia is a potent mechanism for the expression of BNP. The increase in BNP expression under ischemic conditions is independent from concomitant mechanical alterations.

NT-ProBNP predicts rhythm stability after cardioversion of lone atrial fibrillation

BACKGROUND

The aim of the present study was: (1) to determine the predictive value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) on the success of an elective direct-current cardioversion; and (2) to assess the ability to monitor rhythm stability after electrical cardioversion in patients with lone atrial fibrillation (AF).

METHODS AND RESULTS

Fifty-three patients with lone AF were provided with an Holter-ECG for a follow-up period of 4 weeks after elective cardioversion. NT-proBNP serum levels were measured before and 4 weeks after cardioversion. All patients presented with increased NT-proBNP serum levels (median 874 pg/ml, interquartile range 703-1,355) before cardioversion. Thirty patients were in sinus rhythm (SR) during follow-up. These patients showed a significant NT-proBNP-decrease (759 pg/ml, 618-1,139 to 318 pg/ml, 200-523, p<0.05). Nineteen patients experienced a relapse of AF. NT-proBNP was significantly higher prior to cardioversion in comparison to patients without relapse (p<0.05) and remained unchanged during follow-up (1,124 pg/ml, 925-1,542 vs 1,256 pg/ml, 945-1,509, p=NS). Four patients had short periods of silent AF detected by Holter ECG. These patients had a smaller decrease in NT-proBNP than patients with stable SR. The area under the curve of the receiver-operating characteristic curve was 0.8 for NT-proBNP to predict a successful cardioversion. Using an optimized cut-off level of 900 pg/ml, successful cardioversion can be predicted with high accuracy.

CONCLUSIONS

The probability of a successful cardioversion correlates inversely with NT-proBNP values. The short-term success of a cardioversion might be predicted by prior determination of NT-proBNP.

Usefulness of myocardial performance index and biochemical markers for early detection of anthracycline-induced cardiotoxicity in adults

BACKGROUND

Anthracycline therapy is limited by cardiotoxicity. Currently no diagnostic parameter is available allowing ubiquitous and reliable detection of preclinical anthracycline cardiomyopathy and prediction of prognosis.

PATIENTS AND METHODS

In 100 consecutive patients receiving anthracycline-based chemotherapy serial measurements of left ventricular systolic and diastolic function, Tei index (a Doppler echocardiographic parameter of global ventricular function), cardiac troponin T (cTnT) and NT-probrain natriuretic peptides (BNP) at baseline and during 1-year follow-up were performed.

RESULTS

Mean ejection fraction (LVEF) significantly decreased immediately after completion of anthracycline therapy (mean dose 226.1 +/- 8.3 mg/m(2)) und further declined during follow-up (65.9 +/- 0.6% Vs. 61.6 +/- 0.7%; P < 0.001), while mean E/A ratio decreased after 6 months (P = 0.05). No patient presented with cardiac symptoms. The Tei index increased after therapy in the majority of patients (78.8%) compared with pre-therapy values indicating myocardial alteration in more patients than previously recognized. cTnT levels did not exceed the upper limit of the normal range in any patient. Seven patients had low-level elevations of cTnT. Only one of these patients developed a concomitant decrease in LVEF. Mean N-terminal-pro-BNP (NT-proBNP) levels did not significantly change after anthracycline administration. However, in 13 patients (15.3%) a marked, transient increase of NT-proBNP was obtained after the first anthracycline cycle without cardiac dysfunction presumably due to altered cardiac loading conditions during chemotherapy.

CONCLUSION

Low to moderate doses of anthracyclines resulted in subclinical myocardial alteration in more patients than so far noticed. Clinical implications of increased Tei index remain to be determined in long-term. Our results do not support that assessment of cTnT or BNP levels may safely replace serial echocardiographic evaluation of systolic and diastolic function for the monitoring of anthracycline cardiotoxicity.

Lipoprotein-associated phospholipase A2 for early risk stratification in patients with suspected acute coronary syndrome: a multi-marker approach: the North Wuerttemberg and Berlin Infarction Study-II (NOBIS-II)

AIMS

Numerous markers have been identified as useful predictors of major adverse cardiac events (MACE) in patients with suspected acute coronary syndrome (ACS). However, only little is known about the relative benefit of the single markers in risk stratification and the best combination for optimising prognostic power. The aim of the present study was to define the role of the emerging cardiovascular risk marker lipoprotein-associated phospholipase A2 (Lp-PLA2) in a multi-marker approach in combination with troponin I (TnI), NT-proBNP, high sensitivity (hs)CRP, and D-dimer in patients with ACS.

METHODS AND RESULTS

A total of 429 consecutive patients (age 60.5+/-14.1 years, 60.6% male) who were admitted to the emergency room with suspected ACS were analysed in the study. Biochemical markers were measured by immunoassay techniques. All patients underwent point-of-care TnI testing and early coronary angiography if appropriate, in accordance with the current guidelines. Classification and regression trees (CART) and logistic regression techniques were employed to determine the relative predictive power of markers for the primary end-point defined as any of the following events within 42 days after admission: death, non-fatal myocardial infarction, unstable AP requiring admission, admission for decompensated heart failure or shock, percutaneous coronary intervention, coronary artery bypass grafting, life threatening arrhythmias or resuscitation. The incidence of the primary end-point was 13.1%, suggesting a mild to moderate risk population. The best overall risk stratification was obtained using NT-proBNP at a cut-off of 5000 pg/mL (incidence of 40% versus 10.3%, relative risk (RR) 3.9 (95% CI 2.4-6.3)). In the remaining lower risk group with an incidence of 10.3%, further separation was performed using TnI (cut-off 0.14 microg/L; RR=3.1 (95% CI 1.7-5.5) 23.2% versus 7.5%) and again NT-proBNP (at a cut-off of 140 ng/L) in patients with negative TnI (RR=3.2 (95% CI 1.3-7.9), 11.7% versus 3.6%). A final significant stratification in patients with moderately elevated NT-proBNP levels was achieved using Lp-PLA2 at a cut-off of 210 microg/L) (17.9% versus 6.9%; RR=2.6 (95% CI 1.1-6.6)). None of the clinical or ECG variables of the TIMI (Thrombolysis In Myocardial Infarction) risk score provided comparable clinically relevant information for risk stratification.

CONCLUSIONS

In the setting of stateof- the-art coronary care for patients with suspected ACS in the emergency room, NT-proBNP, troponin I, and Lp-PLA2 are effective independent markers for risk stratification that proved to be superior to the TIMI risk score. Lp-PLA2 turned out to be a more effective risk marker than hsCRP in these patients.