N-terminal B-type natriuretic peptide predicts extent of coronary artery disease and ischemia in patients with stable angina pectoris

NT-pro BNP level at dialysis initiation is a useful biomarker for predicting hospitalization for ischemic heart disease

BACKGROUND

Patients with end-stage kidney disease (ESKD) are at high risk of cardiovascular disease including stroke, heart failure, and ischemic heart disease (IHD). To prevent the occurrence and progression of CVD, a reliable prognostic cardiac biomarker is essential. We investigated the prognostic value of NT-proBNP for each incident type of CVD.

METHODS

Male patients from the Ibaraki Dialysis Initiation Cohort (iDIC) study with preserved serum samples from dialysis initiation day (n = 212) were analyzed. Patients were classified into four groups according to quartiles of baseline NT-pro BNP levels. The relationship between NT-proBNP levels at the initiation of dialysis and the subsequent incidence of hospitalization events due to IHD, heart failure, and stroke was analyzed.

RESULTS

The incidence rate for hospitalization due to IHD was significantly higher in the highest NT-proBNP category (Log rank p = 0.008); those of stroke and heart failure showed no significant differences among quartiles. Cox proportional hazards regression analysis revealed that serum NT-proBNT was the only prognostic factor for hospitalization for IHD after adjustment by major known IHD risk factors. (HR, 1.008; 95% confidence interval, 1.002-1.014; p = 0.01) The ROC curve analysis for the incidence of hospitalization due to IHD showed that NT-proBNP had an area under the curve (AUC) of 0.759 (95% CI 0.622-0.897; p = 0.004) at a cut-off value of 956.6 pg/mL.

CONCLUSION

NT-proBNP measurement at the initiation of dialysis therapy is useful to predict later hospitalization for IHD.

TRIAL REGISTRATION

UMIN000010806.

Chronic Kidney Disease Associated with Ischemic Heart Disease: To What Extent Do Biomarkers Help?

Chronic kidney disease represents a complex and multifaceted pathology characterized by the presence of structural or functional renal anomalies associated with a persistent reduction in renal function. As the disease progresses, complications arise due to the chronic inflammatory syndrome, hydro-electrolytic disorders, and toxicity secondary to the uremic environment. Cardiovascular complications are the leading cause of death for these patients. Ischemic cardiac pathology can be both a consequence and complication of chronic kidney disease, highlighting the need to identify specific cardiorenal dysfunction biomarkers targeting pathophysiological mechanisms common to both conditions. This identification is crucial for establishing accurate diagnoses, prognoses, and risk stratifications for patients. This work is intended to elucidate the intricate relationship between chronic kidney disease and ischemic heart disease and to investigate the roles of cardiorenal biomarkers, including cardiac troponin, natriuretic peptides, galectin-3, copeptin, fibroblast growth factor 23 and its co-receptor Klotho, soluble suppression of tumorigenicity 2, and plasma growth differentiation factor 15.

Multiple Biomarkers to Predict Major Adverse Cardiovascular Events in Patients With Coronary Chronic Total Occlusions

Background

There are limited tools available to predict the long-term prognosis of persons with coronary chronic total occlusions (CTO).

Objectives

We evaluated performance of a blood biomarker panel to predict cardiovascular (CV) events in patients with CTO.

Methods

From 1251 patients in the CASABLANCA study, 241 participants with a CTO were followed for an average of 4 years for occurrence of major adverse CV events (MACE, CV death, non-fatal myocardial infarction or stroke) and CV death/heart failure (HF) hospitalization. Results of a biomarker panel (kidney injury molecule-1, N-terminal pro-B-type natriuretic peptide, osteopontin, and tissue inhibitor of metalloproteinase-1) from baseline samples were expressed as low-, moderate-, and high-risk.

Results

By 4 years, a total of 67 (27.8%) MACE events and 56 (23.2%) CV death/HF hospitalization events occurred. The C-statistic of the panel for MACE through 4 years was 0.79. Considering patients in the low-risk group as a reference, the hazard ratio of MACE by 4 years was 6.65 (95% confidence interval [CI]: 2.98-14.8) and 12.4 (95% CI:5.17-29.6) for the moderate and high-risk groups (both P <0.001). The C-statistic for CVD/HF hospitalization by 4 years was 0.84. Compared to the low-risk score group, the moderate and high-risk groups had hazard ratios of 5.61 (95% CI: 2.33-13.5) and 15.6 (95% CI: 6.18, 39.2; both P value <0.001).

Conclusion

A multiple biomarker panel assists in evaluating the risk of adverse outcomes in patients with coronary CTO. These results may have implications for patient care and could have a role for clinical trial enrichment.

Clinical Trial

CASABLANCA, ClinicalTrials.gov Identifier: NCT00842868.

Biomarkers to monitor the prognosis, disease severity, and treatment efficacy in coronary artery disease

INTRODUCTION

Coronary Artery Disease (CAD) is a prevalent condition characterized by the presence of atherosclerotic plaques in the coronary arteries of the heart. The global burden of CAD has increased significantly over the years, resulting in millions of deaths annually and making it the leading health-care expenditure and cause of mortality in developed countries. The lack of cost-effective strategies for monitoring the prognosis of CAD warrants a pressing need for accurate and efficient markers to assess disease severity and progression for both reducing health-care costs and improving patient outcomes.

AREA COVERED

To effectively monitor CAD, prognostic biomarkers and imaging techniques play a vital role in risk-stratified patients during acute treatment and over time. However, with over 1,000 potential markers of interest, it is crucial to identify the key markers with substantial utility in monitoring CAD progression and evaluating therapeutic interventions. This review focuses on identifying and highlighting the most relevant markers for monitoring CAD prognosis and disease severity. We searched for relevant literature using PubMed and Google Scholar.

EXPERT OPINION

By utilizing the markers discussed, health-care providers can improve patient care, optimize treatment plans, and ultimately reduce health-care costs associated with CAD management.

Predictive Value of N-Terminal Pro B-Type Natriuretic Peptide for Contrast-Induced Nephropathy Non-Recovery and Poor Outcomes Among Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

Contrast-induced nephropathy (CIN) is a frequent complication in patients undergoing percutaneous coronary intervention (PCI). The degree of recovery of renal function from CIN may affect long-term prognosis. N-terminal pro B-type natriuretic peptide (NT-proBNP) is a simple but useful biomarker for predicting CIN. However, the predictive value of preprocedural NT-proBNP for CIN non-recovery and long-term outcomes in patients undergoing PCI remains unclear.Methods and Results: This study prospectively enrolled 550 patients with CIN after PCI between January 2012 and December 2018. CIN non-recovery was defined as persistent serum creatinine >25% or 0.5 mg/dL over baseline from 1 week to 12 months after PCI in patients who developed CIN. CIN non-recovery was observed in 40 (7.3%) patients. Receiver operating characteristic analysis indicated that the best NT-proBNP cut-off value for detecting CIN non-recovery was 876.1 pg/mL (area under the curve 0.768; 95% confidence interval [CI] 0.731-0.803). After adjusting for potential confounders, multivariable analysis indicated that NT-proBNP >876.1 pg/mL was an independent predictor of CIN non-recovery (odds ratio 1.94; 95% CI 1.03-3.75; P=0.0042). Kaplan-Meier curves showed higher rates of long-term mortality among patients with CIN non-recovery than those with CIN recovery (Chi-squared=14.183, log-rank P=0.0002).

CONCLUSIONS

Preprocedural NT-proBNP was associated with CIN non-recovery among patients undergoing PCI. The optimal cut-off value for NT-proBNP to predict CIN non-recovery was 876.1 pg/mL.

Risk factors for cardiovascular disease among individuals with hepatic steatosis

Cardiovascular disease (CVD) is the leading cause of mortality in adults with hepatic steatosis (HS). However, risk factors for CVD in HS are unknown. We aimed to identify factors associated with coronary artery disease (CAD) and incident major adverse cardiovascular events (MACE) in individuals with HS. We performed a nested cohort study of adults with HS detected on coronary computed tomography in the PROspective Multicenter Imaging Study for Evaluation of chest pain (PROMISE) trial. Obstructive CAD was defined as ≥50% coronary stenosis. MACE included hospitalization for unstable angina, nonfatal myocardial infarction, or all-cause death. Multivariate modeling, adjusted for age, sex, atherosclerotic CVD (ASCVD) risk score and body mass index, identified factors associated with obstructive CAD. Cox regression, adjusted for ASCVD risk score, determined the predictors of MACE. A total of 959 of 3,756 (mean age 59.4 years, 55.0% men) had HS. Obstructive CAD was present in 15.2% (145 of 959). Male sex (adjusted odds ratio [aOR] = 1.83, 95% confidence interval [CI] 1.18-1.2.84; p = 0.007), ASCVD risk score (aOR = 1.05, 95% CI 1.03-1.07; p < 0.001), and n-terminal pro-b-type natriuretic peptide (NT-proBNP; aOR = 1.90, 95% CI 1.38-2.62; p < 0.001) were independently associated with obstructive CAD. In the 25-months median follow-up, MACE occurred in 4.4% (42 of 959). Sedentary lifestyle (adjusted hazard ratio [aHR] = 2.53, 95% CI 1.27-5.03; p = 0.008) and NT-proBNP (aOR = 1.50, 95% CI 1.01-2.25; p = 0.046) independently predicted MACE. Furthermore, the risk of MACE increased by 3% for every 1% increase in ASCVD risk score (aHR = 1.03, 95% CI 1.01-1.05; p = 0.02). Conclusion: In individuals with HS, male sex, NT-pro-BNP, and ASCVD risk score are associated with obstructive CAD. Furthermore, ASCVD, NT-proBNP, and sedentary lifestyle are independent predictors of MACE. These factors, with further validation, may help risk-stratify adults with HS for incident CAD and MACE.

Extracellular Vesicles in Diagnosing Chronic Coronary Syndromes the Bumpy Road to Clinical Implementation

Coronary artery disease (CAD), comprising both acute coronary syndromes (ACS) and chronic coronary syndromes (CCS), remains one of the most important killers throughout the entire world. ACS is often quickly diagnosed by either deviation on an electrocardiogram or elevated levels of troponin, but CCS appears to be more complicated. The most used noninvasive strategies to diagnose CCS are coronary computed tomography and perfusion imaging. Although both show reasonable accuracy (80–90%), these modalities are becoming more and more subject of debate due to costs, radiation and increasing inappropriate use in low-risk patients. A reliable, blood-based biomarker is not available for CCS but would be of great clinical importance. Extracellular vesicles (EVs) are lipid-bilayer membrane vesicles containing bioactive contents e.g., proteins, lipids and nucleic acids. EVs are often referred to as the “liquid biopsy” since their contents reflect changes in the condition of the cell they originate from. Although EVs are studied extensively for their role as biomarkers in the cardiovascular field during the last decade, they are still not incorporated into clinical practice in this field. This review provides an overview on EV biomarkers in CCS and discusses the clinical and technological aspects important for successful clinical application of EVs.

Efficacy of clopidogrel and ticagrelor under NT-proBNP in hospitalized ST-elevation acute coronary syndrome patients on percutaneous coronary intervention: CCC-ACS Project Analysis

BACKGROUND

Risk stratification with specific biomarkers is proposed for tailored P2Y12 inhibitor therapy in patients with STEMI.

METHODS

This nationwide registry and quality improvement study is from November 1, 2014, to June 30, 2017. In total, 11,512 STEMI patients received aspirin and P2Y12 receptor inhibitor (clopidogrel or ticagrelor) and underwent PCIs in hospitals. Of the patients, 2992 were prescribed ticagrelor and 8520 clopidogrel. The primary effectiveness outcome was major adverse cardiovascular and cerebrovascular events (MACCE: cardiac death, myocardial infarction, stent thrombosis, in-hospital ischemic stroke). The primary safety outcome was in-hospital major bleeding.

RESULTS

MACCE incidence was lower in the ticagrelor group than in the clopidogrel group (0.8% versus 1.2%; P=0.046), but under different NT-proBNP levels, cumulative hazards of MACCE were without statistical significance. Bleeding rates were higher in the ticagrelor group than in the clopidogrel group (all bleeding: 9.9% versus 6.9%, P<0.001; major bleeding: 4.0% versus 2.7%, P<0.001). The higher cumulative hazard of bleeding could be identified in the Kaplan-Meier curves. In the multivariate analysis, ticagrelor increased bleeding events, compared with clopidogrel, at NT-proBNP >1800 ng/L patients (all bleeding: HR 1.46; 95%CI, 1.07-2.01; major bleeding: HR 1.68, 95%CI, 1.03-2.74), but a low effect was found in those with lower NT-proBNP level. Subgroup analyses show that ticagrelor increased major bleeding in patients with left ventricular ejection fraction (LVEF) <0.50 (HR 3.29; 95% CI 1.61-6.74) (interaction p=0.03).

CONCLUSION

We found that ticagrelor, compared with clopidogrel, increased bleeding complications in hospitalized patients with NT-proBNP>1800 ng/L, especially in patients with EF < 0.50.

Angiopoietin-2 provides no incremental predictive value for the presence of obstructive coronary artery disease over N-terminal pro-brain natriuretic peptide

BACKGROUND

Using circulating biomarkers as a noninvasive method to assist the evaluation of coronary artery disease (CAD) is beneficial for reducing the unnecessary diagnostic cardiac catheterization. This study aimed to assess the predictive role of angiopoietin-2 (Ang-2) for the presence of obstructive coronary stenosis as compared with N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with symptoms of CAD.

METHODS

The study enrolled 222 consecutive symptomatic patients who underwent elective diagnostic cardiac catheterization from July to December 2018. Blood samples were collected in the first morning after admission. The severity of coronary stenosis was assessed by coronary angiography. The obstructive CAD was defined as stenosis ≥50% of the left main coronary artery or stenosis ≥70% of a major epicardial vessel (left anterior descending artery, left circumflex artery and right coronary artery).

RESULTS

Patients with obstructive CAD (n = 120) had significantly higher levels of Ang-2 and NT-proBNP compared with those without. In multivariable regression analysis, only NT-proBNP levels were independently associated with Ang-2 levels. NT-proBNP was superior to Ang-2 as a predictor for the presence of obstructive CAD (NT-proBNP, area under curve [AUC] = 0.733, vs Ang-2, AUC = 0.626, P = 0.004). In multiple logistic regression analysis, NT-proBNP, but not Ang-2, was the independent predictor of obstructive CAD. The combination of Ang-2 with NT-proBNP did not provide the incremental value over NT-proBNP alone.

CONCLUSION

Serum Ang-2 levels are associated with NT-proBNP levels in patients suspected for CAD. NT-proBNP is superior to Ang-2 as a predictor for the presence of obstructive CAD. However, Ang-2 does not further increase diagnostic accuracy on top of NT-proBNP.

Predictive value of N-terminal-Pro brain natriuretic peptide in the detection of coronary artery disease in patients with positive myocardial perfusion imaging

Background: N-terminal pro-brain natriuretic peptide (NT-ProBNP) increases during myocardial ischemia and has a potential for the diagnosis of patients with coronary artery disease (CAD). We aimed to determine the incremental diagnostic value of NT-ProBNP in the selection of patients with positive myocardial perfusion imaging (MPI) for coronary angiography. We also tested the association between the level of NT-ProBNP and severity of CAD based on the vessel score and Gensini score.

Methods: In this cross-sectional study, stable angina patients with positive MPI who were assessed by coronary angiography in Imam Khomeini Hospitalwere enrolled. After the collection of demographic and clinical data, NT-ProBNP was measured in all patients on the day of coronary angiography, and its association with the presence of CAD, vessel score and Gensini score was tested.

Results: We enrolled 170 patients (mean age61.2±10.1 years, 86 males (50.6%)). Seventy-two (42.3%) patients had at least one stenotic vessel. NT-Pro BNP was significantly higher in the CAD-positive group (OR=1.01, 95% CI: 1.00-1.02; p=0.008) and could independently predict the presence of CAD at a cut-off point of 69.5, with a sensitivity of 55.6%, specificity of 82.5% and diagnostic accuracy of 61.7%. The Gensini score had a modest correlation with NT-Pro BNP (r=0.60, p<0.001). The combination of MPI result and NT-Pro BNP could predict the presence of CAD (OR=14.57, 95% CI: 4.28, 49.56; p<0.001).

Conclusion: Serum level of NT-Pro BNP alone and its combination with the results of MPI can significantly predict the presence of CAD and therefore, highlights the need for performing coronary angiography.

The effect of percutaneous coronary revascularization on plasma N-terminal pro-B-type natriuretic peptide levels in stable coronary artery disease

Background

This study was conducted to assess the effect of percutaneous coronary revascularization (PCR) on plasma NT-proBNP concentration in patients with chronic stable angina (CSA).

Methods

This prospective open label interventional study included 22 patients with moderate to severe CSA, normal left ventricular (LV) systolic functions and critical (>90%) proximal stenosis in one of the three major epicardial coronary arteries. After stabilization of medications for 8 weeks, resting supine plasma NT-proBNP levels were measured and patients underwent PCR of the involved vessels. Eight weeks later, with medications unaltered; plasma NT-proBNP levels were repeated and compared with the baseline levels. LV systolic and diastolic functions were assessed before and after PCR.

Results

The mean age of the patients was 61.27 ± 8.87 years. Out of 22 patients, 20 were male and 2 were female. PCR was performed on left anterior descending coronary artery (LAD) in 12 patients and in a non-LAD vessel in 10 patients. After 8 weeks of successful PCR, there was a significant overall reduction in mean plasma NT-proBNP levels (from 244.36 ± 218.99 to 168.68 ± 161.61 pg/mL, p = 0.016). The patients who underwent PCR of LAD demonstrated significantly reduced NT-pro-BNP levels after PCR (p = 0.009). In the non-LAD group, NT-proBNP levels also decreased, albeit insignificantly (p = 0.432). Reduction in NT-proBNP was independent of change in LV systolic functions.

Conclusion

Successful PCR, by relieving myocardial ischemia, significantly reduced plasma NT-proBNP levels in majority of the patients with chronic stable angina secondary to critical epicardial coronary artery stenosis.

Biomarkers in stable coronary artery disease

Coronary artery disease (CAD) remains a significant cause of morbidity and mortality around the world. Patients with stable CAD can have an unpredictable clinical trajectory; thus, additional tools to prognosticate risk in this cohort are warranted. In recent years, a wide range of biomarkers has been recognized for their diagnostic capabilities in patients with stable CAD, identifying those with obstructive disease who may require more intensive preventive therapies or even consideration of percutaneous coronary intervention in some circumstances. In addition, a multiple-biomarker approach may identify stable CAD patients at highest risk for future major adverse cardiac events. Thus, randomized controlled trials to assess biomarker-guided preventive therapy in this cohort appear warranted.

High Sensitivity Troponins Discriminate Different Morphologies of Coronary Artery Plaques Being Assessed by Coronary Computed Tomography Angiography

BACKGROUND

This study evaluates the association between high sensitivity troponin I (hsTnI) and T (hsTnT) and the morphology of coronary artery plaques detected by coronary computed tomography angiography (CCTA) in patients with suspected coronary artery disease (CAD).

METHODS

Patients undergoing CCTA were prospectively enrolled. CCTA was indicated by a low to intermediate pretest probability for CAD during routine clinical care. Within 24 hours of CCTA examination, peripheral blood samples were taken to measure hsTnI, hsTnT, and N-terminal probrain natriuretic peptide (NT-proBNP).

RESULTS

A total of 99 patients were enrolled with 43% without CAD, 9% with noncalcified plaques, 28% with calcified plaques, and 19% with mixed type plaque lesions. Both hsTnI and hsTnT levels were able to discriminate significantly between the groups, especially in the presence of mixed coronary plaques (AUC range: 0.741-0.752; p = 0.0001). In multivariate logistic regression models, hsTnT, but not hsTnI, was still significantly associated with mixed coronary plaque morphology (odds ratio = 8.968; 95% CI 1.999-40.241; p = 0.004).

CONCLUSIONS

Both hsTnI and hsTnT are able to discriminate between different coronary artery plaques morphologies, whereas hsTnT was significantly associated with mixed coronary plaques in patients with suspected CAD. This trial is registered with NCT03074253.

Association of N-terminal pro-brain natriuretic peptide with contrast-induced acute kidney injury and long-term mortality in patients with heart failure and mid-range ejection fraction: An observation study

The potential value of N-terminal pro-brain natriuretic peptide (NT-proBNP) for contrast-induced acute kidney injury (CI-AKI) in patients with heart failure and mid-range ejection fraction (HFmrEF) is unclear. We investigated whether NT-proBNP is associated with CI-AKI and long-term mortality following elective cardiac catheterization in patients with HFmrEF.A total of 174 consecutive patients with HFmrEF undergoing elective coronary angiography or intervention were enrolled. The primary endpoint was the development of CI-AKI, defined as an absolute increase of ≥0.3 mg/dL or ≥ 50% from baseline serum creatinine with 48 hours after contrast medium exposure. Receiver-operating characteristic curve analysis was conducted, and Youden index was used to determine the best cutoff NT-proBNP value. Multivariable logistic regression and Cox proportional hazards regression analyses were performed to identify the independent risk factors for CI-AKI and long-term mortality, respectively.The incidence of CI-AKI was 12.1%. Patients with CI-AKI had higher NT-proBNP values than those without (4373[1561.9-7470.5] vs 1303[625.2-2482.3], P = 0.003). Receiver-operating characteristic curve revealed that NT-proBNP was not significantly different from the Mehran risk score in predicting CI-AKI (area under the curve [AUC] = 0.723 vs 0.767, P = 0.516). The best cutoff NT-proBNP value for CI-AKI was 3299 pg/mL, with 70.6% sensitivity and 83.1% specificity. Multivariable analysis demonstrated that NT-proBNP ≥3299 pg/mL is significantly related to CI-AKI (odds ratio = 12.79; 95% confidence interval, 3.18-51.49; P < 0.001). Cox regression analysis showed that NT-proBNP ≥3299 pg/mL is associated with long-term mortality (adjusted hazard ratio = 11.91; 95%CI, 2.16-65.70; P = 0.004) during follow-up.In patients with HFmrEF, NT-proBNP ≥3299 pg/mL is associated with CI-AKI and long-term mortality following elective coronary angiography or intervention.

Natriuretic Peptide and High-Sensitive Troponin T Concentrations Correlate with Effectiveness of Short-Term CPAP in Patients with Obstructive Sleep Apnea and Coronary Artery Disease

The risk of cardiovascular complications is increased in patients with obstructive sleep apnea (OSA). Continuous positive airway pressure (CPAP) is the most effective way to treat clinically significant OSA. We hypothesized that the concentrations of the cardiac risk markers N-terminal brain natriuretic peptide (NT-proBNP) and high-sensitive troponin T (hs-TropT) correlate with the effectiveness of CPAP therapy in patients with OSA and coexisting coronary artery disease (CAD). Twenty-one patients with severe OSA and coexisting CAD (group 1) and 20 control patients with severe OSA alone (group 2) were treated with CPAP and monitored by laboratory-based polysomnography. NT-proBNP and hs-TropT levels were measured before and after CPAP. Apnea-hypopnea index (AHI) and oxygen desaturation were similar in both groups. In group 1, hs-TropT levels correlated with AHI and oxygen desaturation upon CPAP. Elevated NT-proBNP levels in group 1 were significantly reduced by CPAP. NT-proBNP levels correlated with AHI and showed negative correlation with ST-segment depression. No such correlations were found in group 2. CPAP has the potential to normalize elevated NT-proBNP serum levels in patients with severe OSA and coexisting CAD. Levels of NT-proBNP and hs-TropT correlated with AHI and oxygen desaturation.

Incremental value of B-type natriuretic peptide for detection and risk reclassification of obstructive coronary artery disease on computed tomography angiography

BACKGROUND

B-type natriuretic peptide (BNP) is well known to increase as a result of left ventricular systolic dysfunction and is a useful diagnostic marker for heart failure. The purpose of this study was to assess the incremental value of BNP for predicting obstructive coronary artery disease (CAD) on computed tomography angiography (CTA) in patients with suspected CAD.

METHODS

This was an observational analysis of patients with stable CAD undergoing CTA in our institution between April 2008 and June 2014. Consecutive 947 patients with suspected CAD who underwent 64-slice CTA were enrolled. Obstructive CAD was defined as more than 50% luminal narrowing. We divided the patients into 2 groups according to median BNP value (20.3pg/ml). Duke clinical score for obstructive CAD was calculated for each patient.

RESULTS

Obstructive CAD was found in 273 (28.0%) patients. Median follow-up period was 37 months (interquartile range 21-55 months). Kaplan-Meier curves showed that BNP above median was significantly associated with major adverse cardiac events (p=0.001). In multivariable logistic analysis, patients with BNP above median were associated with the presence of obstructive CAD, as compared with BNP below median [odds ratio, 2.55; 95% confidence interval (CI), 1.79-3.63; p<0.001]. Analyzing the incremental value of the Duke clinical score and BNP, the predictive value of the Duke clinical score [area under the curve (AUC), 0.714] could be increased by BNP (AUC 0.745 for the combined model; p<0.001). Addition of BNP to a model containing the Duke clinical score resulted in net reclassification improvement index of 0.14 (95% CI: 0.053-0.205, p<0.001).

CONCLUSIONS

BNP might provide an incremental improvement in the detection of obstructive CAD on CTA when combined with a conventional cardiovascular risk score.

Correlation between brain natriuretic peptide levels and the prognosis of patients with left ventricular diastolic dysfunction

The present study aimed to investigate the association between brain natriuretic peptide (BNP) levels and the prognosis of patients with left ventricular (LV) diastolic dysfunction. A total of 708 inpatients with cardiovascular disease (mean age, 66 years; 395 males and 313 females) were grouped according to initial BNP and were followed-up for 20-51 months (average, 30.86 months) until endpoint events occurred. Endpoints were defined as mortality or readmission due to cardiovascular disease, or mortality due to any other reason. A total of 67 and 77 events were reported in the BNP ≤80 pg/ml and BNP >80 pg/ml groups, respectively. The occurrence rate of the endpoint was significantly higher in the BNP >80 pg/ml group, as compared with the BNP ≤80 pg/ml group (26.28 vs. 16.14%; relative risk=1.63). Furthermore, the durations of patient survival were significantly shorter in the BNP >80 pg/ml group, as compared with the BNP ≤80 pg/ml group (P=0.0006), and patient survival decreased as BNP levels rose (P=0.0074). Among the 708 patients, 677 underwent echocardiographic detection at the same time. No significant correlation was detected between BNP levels and survival time in 178 patients with normal LV diastolic function [mitral Doppler flow, early diastolic (E)/late diastolic (A)>1] (P=0.2165); whereas a negative correlation was determined in 499 patients with LVD dysfunction (E/A≤1) (Spearman's rho=-0.0899; P=0.0447). The prognoses of patients with elevated BNP levels were correspondingly worse in the present study and these correlations were demonstrated to be significant in patients with LV diastolic dysfunction. Therefore, BNP levels may be used to predict the prognosis of patients with cardiovascular disease.

Association between serum N-terminal pro-B-type natriuretic peptide levels and characteristics of coronary atherosclerotic plaque detected by coronary computed tomography angiography

The aim of the present study was to explore the association between the levels of serum N-terminal pro-B-type natriuretic peptide (NT-pro BNP) and the characteristics of coronary atherosclerotic plaque detected by coronary computed tomography angiography (CCTA), in patients with unstable angina (UA). A total of 202 patients (age range, 47-82 years) were divided into the following three groups: Non-cardiac disease group (57 patients); stable angina pectoris (SAP) group (62 patients); and UA group (83 patients). There were significant differences between the serum NT-pro BNP levels among the three groups (P=0.007). However, in multivariant diagnoses, NT-pro BNP level was not an independent risk factor for UA. The levels of serum NT-pro BNP were observed to be positively correlated with the number of vessels involved (r=0.462; P<0.001), SIS (r=0.475; P<0.001), segment-stenosis score (r=0.453; P<0.001), coronary calcification score (r=0.412; P=0.001), number of obstructive diseases (r=0.346; P<0.001), and the number of segments with non-calcified plaque (r=0.235; P=0.017), mixed plaque (r=0.234; P=0.017) and calcified plaque (r=0.431; P<0.001). The levels of serum NT-pro BNP were significantly higher in patients with UA and left main-left anterior descending (LM-LAD) disease, compared with UA patients without LM-LAD disease (P<0.001). In addition, serum NT-pro BNP was significantly higher in patients with obstructive disease and UA than in those without obstructive disease (P<0.001). The area under the curve of log(NT-pro BNP) was 0.656 (P=0.006; optimal cut-off value, 1.74; sensitivity, 77.6%; specificity, 51.9%). In conclusion, the levels of serum NT-pro BNP are associated with the burden and severity of coronary artery atherosclerotic disease in patients with UA, and may be helpful in risk stratification of patients with UA.

Cardiopulmonary laboratory biomarkers in the evaluation of acute dyspnea

Dyspnea is a common chief complaint in the emergency department, with over 4 million visits annually in the US. Establishing the correct diagnosis can be challenging, because the subjective sensation of dyspnea can result from a wide array of underlying pathology, including pulmonary, cardiac, neurologic, psychiatric, toxic, and metabolic disorders. Further, the presence of dyspnea is linked with increased mortality in a variety of conditions, and misdiagnosis of the cause of dyspnea leads to poor patient-level outcomes. In combination with the history and physical, efficient, and focused use of laboratory studies, the various cardiopulmonary biomarkers can be useful in establishing the correct diagnosis and guiding treatment decisions in a timely manner. Use and interpretation of such tests must be guided by the clinical context, as well as an understanding of the current evidence supporting their use. This review discusses current standards and research regarding the use of established and emerging cardiopulmonary laboratory markers in the evaluation of acute dyspnea, focusing on recent evidence assessing the diagnostic and prognostic utility of various tests. These markers include brain natriuretic peptide (BNP) and N-terminal prohormone (NT-proBNP), mid-regional peptides proatrial NP and proadrenomedullin, cardiac troponins, D-dimer, soluble ST2, and galectin 3, and included is a discussion on the use of arterial and venous blood gases.

The ethnicity-specific association of biomarkers with the angiographic severity of coronary artery disease

Background

Risk factor burden and clinical characteristics of patients with coronary artery disease (CAD) differ among ethnic groups. We related biomarkers to CAD severity in Caucasians, Chinese, Indians and Malays.

Methods

In the Dutch-Singaporean UNICORN coronary angiography cohort (n = 2033) we compared levels of five cardiovascular biomarkers: N-terminal pro-brain natriuretic peptide (NTproBNP), high-sensitivity C-reactive protein (hsCRP), cystatin C (CysC), myeloperoxidase (MPO) and high-sensitivity troponin I (hsTnI). We assessed ethnicity-specific associations of biomarkers with CAD severity, quantified by the SYNTAX score.

Results

Adjusted for baseline differences, NTproBNP levels were significantly higher in Malays than in Chinese and Caucasians (72.1 vs. 34.4 and 41.1 pmol/l, p < 0.001 and p = 0.005, respectively). MPO levels were higher in Caucasians than in Indians (32.8 vs. 27.2 ng/ml, p = 0.026), hsTnI levels were higher in Malays than in Caucasians and Indians (33.3 vs. 16.4 and 17.8 ng/l, p < 0.001 and p = 0.029) and hsTnI levels were higher in Chinese than in Caucasians (23.3 vs. 16.4, p = 0.031). We found modifying effects of ethnicity on the association of biomarkers with SYNTAX score. NTproBNP associated more strongly with the SYNTAX score in Malays than Caucasians (β 0.132 vs. β 0.020 per 100 pmol/l increase in NTproBNP, p = 0.032). For MPO levels the association was stronger in Malays than Caucasians (β 1.146 vs. β 0.016 per 10 ng/ml increase, p = 0.017). Differing biomarker cut-off levels were found for the ethnic groups.

Conclusion

When corrected for possible confounders we observe ethnicity-specific differences in biomarker levels. Moreover, biomarkers associated differently with CAD severity, suggesting that ethnicity-specific cut-off values should be considered.

Effect of Coronary Atherosclerosis and Myocardial Ischemia on Plasma Levels of High-Sensitivity Troponin T and NT-proBNP in Patients With Stable Angina

OBJECTIVE

Circulating levels of high-sensitivity cardiac troponin T (hs-cTnT) and N terminal pro brain natriuretic peptide (NT-proBNP) are predictors of prognosis in patients with coronary artery disease (CAD). We aimed at evaluating the effect of coronary atherosclerosis and myocardial ischemia on cardiac release of hs-cTnT and NT-proBNP in patients with suspected CAD.

APPROACH AND RESULTS

Hs-cTnT and NT-proBNP were measured in 378 patients (60.1±0.5 years, 229 males) with stable angina and unknown CAD enrolled in the Evaluation of Integrated Cardiac Imaging (EVINCI) study. All patients underwent stress imaging to detect myocardial ischemia and coronary computed tomographic angiography to assess the presence and characteristics of CAD. An individual computed tomographic angiography score was calculated combining extent, severity, composition, and location of plaques. In the whole population, the median (25-75 percentiles) value of plasma hs-cTnT was 6.17 (4.2-9.1) ng/L and of NT-proBNP was 61.66 (31.2-132.6) ng/L. In a multivariate model, computed tomographic angiography score was an independent predictor of the plasma hs-cTnT (coefficient 0.06, SE 0.02; P=0.0089), whereas ischemia was a predictor of NT-proBNP (coefficient 0.38, SE 0.12; P=0.0015). Hs-cTnT concentrations were significantly increased in patients with CAD with or without myocardial ischemia (P<0.005), whereas only patients with CAD and ischemia showed significantly higher levels of NT-proBNP (P<0.001).

CONCLUSIONS

In patients with stable angina, the presence and extent of coronary atherosclerosis is related with circulating levels of hs-cTnT, also in the absence of ischemia, suggesting an ischemia-independent mechanism of hs-cTnT release. Obstructive CAD causing myocardial ischemia is associated with increased levels of NT-proBNP.

Preprocedural N-terminal pro-B-type natriuretic peptide as a useful marker for predicting periprocedural myocardial injury following percutaneous coronary intervention in diabetic patients without cardiac dysfunction

BACKGROUND

Elevated preprocedural N-term pro-B-type natriuretic peptide (NT-pro-BNP) and postprocedural cardiac troponin I (cTnI) are related to a poor cardiac outcome in the non-diabetic population. We hypothesized that preprocedural NT-pro-BNP might be a useful marker in predicting periprocedural myocardial injury (PMI) following elective percutaneous coronary intervention (PCI) in type 2 diabetes (T2D).

METHODS

We prospectively enrolled 1194 consecutive diabetic patients with normal cardiac function and preprocedural cTnI who were successfully undergoing elective PCI. Preprocedural NT-pro-BNP levels were assessed at admission, and PMI was evaluated by analysis of cTnI within 24 hours. The relationship between preprocedural NT-pro-BNP levels and the peak values of cTnI after PCI was examined.

RESULTS

Patients with high baseline NT-pro-BNP levels had higher postprocedural cTnI levels (β = 0.123, p < 0.001). In the multivariable model, NT-pro-BNP was associated with higher risk of postprocedural cTnI elevation above 1 × upper limit of normal (ULN, OR, 3.13; 95% CI, 1.51-6.50; p = 0.002), 3 × ULN (OR, 2.44; 95% CI, 1.17-5.08; p = 0.018), 5 × ULN (OR, 3.18; 95% CI, 1.44-7.0; p = 0.004), respectively. Moreover, the incidence of cTnI elevation was higher in patients with the upper tertile of NT-pro-BNP levels than that in ones with the lower tertile of NT-pro-BNP levels (> 1 × ULN: 63.1% vs. 50.0%, p < 0.001; > 3 × ULN: 39.2% vs. 31.9%, p = 0.032; > 5 × ULN: 30.4% vs. 21.9%, p < 0.006; respectively).

CONCLUSIONS

Our data, for the first time, demonstrated that increased preprocedural NT-pro-BNP levels were strongly and independently associated with a higher risk of PMI, suggesting that baseline NT-pro-BNP level might be a useful marker for predicting PMI following PCI in diabetic patients without cardiac dysfunction.

Markers of Myocardial Ischemia in Patients With Coronary Artery Disease and Obstructive Sleep Apnea: Effect of Continuous Positive Airway Pressure Therapy

BACKGROUND

Obstructive sleep apnea (OSA) is associated with an increased risk of cardiovascular complications. OSA and coronary artery disease (CAD) share the same risk factors and coexist in many patients. In previous studies, repeated nocturnal cardiac ischemic events in OSA patients with CAD have been reported.

HYPOTHESIS

We hypothesized that OSA may precipitate myocardial ischemia, evidenced by ST-segment depression and elevated N-terminal brain natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hs-TropT) levels in patients with severe OSA and concomitant CAD. We also aimed to evaluate if the effects could be reversed by continuous positive airway pressure (CPAP) therapy.

METHODS

Twenty-one patients with severe OSA (apnea-hypopnea index >15/h, nadir oxygen desaturation ≤ 80%), and coexisting CAD underwent in-hospital polysomnography at baseline and under CPAP. Blood samples for hs-TropT and NT-proBNP measurements were drawn prior and immediately after sleep. ST-segment depression was measured at the time of maximum oxygen desaturation during sleep.

RESULTS

CPAP significantly decreased elevated NT-proBNP levels from 475 ± 654 pg/mL before sleep to 353 ± 573 pg/mL after sleep and attenuated ST-segment depression during sleep. hs-TropT was not elevated and did not differ after nocturnal oxygen desaturation at baseline and after CPAP.

CONCLUSIONS

CPAP significantly reduced NT-proBNP in patients suffering from severe OSA and coexisting CAD. Repeated nocturnal myocardial ischemia did not cause myocyte necrosis evidenced by elevated hs-TropT or ST-segment depression.

High Sensitive CRP Level Is Associated With Intermediate and High Syntax Score in Patients With Acute Coronary Syndrome

High sensitive C-reactive protein (hs-CRP) levels are associated with short- and long-term mortality in patients with acute coronary syndrome (ACS). We investigated whether baseline hs-CRP levels are associated with burden of coronary atherosclerosis assessed by SYNTAX score (SXScore).We enrolled 321 patients with ACS who underwent coronary angiography. The patients were divided into tertiles according to the SXScore: low SXScore (≤ 22), and intermediate-high SXScore (≥ 23).Subjects in the intermediate-high SXScore tertile had higher serum hs-CRP levels compare to low SXScore tertile patients (7.7 ± 3.4 mg/L versus 4.9 ± 2.5 mg/L, P < 0.001). The mean age of patients and prevalance of diabetes in the intermediate-high SXScore tertile were significantly higher than in the low SXScore tertile (63 ± 13 versus 58 ± 12 years P = 0.001 for age, P = 0.007 for diabetes). Multivariate logistic regression analysis showed that the strongest predictors of high SXScore were increased serum hs-CRP levels (OR: 1.14) together with multivessel disease (OR: 0.23), left ventricular ejection fraction (LVEF) (OR: 0.90), and troponin levels (OR: 1.12).Serum hs-CRP levels on admission in patients with ACS could predict the severity and complexity of coronary atherosclerosis together with multivessel disease, LVEF, and troponin levels. Thus, increased serum levels of hs-CRP were one of the strong predictors of high SXScore in ACS patients.

Markers of Myocardial Ischemia in Patients with Obstructive Sleep Apnea and Coronary Artery Disease

Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia during sleep. We tested the hypothesis that nocturnal myocardial ischemia is detectable by ST segment depression and elevation of high sensitive troponin T (hsTrop T) and B-type natriuretic peptide (NT-proBNP) in patients with OSA and coexisting coronary artery disease (CAD). Twenty-one patients with OSA and CAD and 20 patients with OSA alone underwent in-hospital polysomnography. Blood samples for hsTrop T and NT-proBNP measurements were drawn before and after sleep. ST segment depression was measured at the time of maximum oxygen desaturation during sleep. The apnea-hypopnea-index (AHI), oxygen saturation nadir, and time in bed with oxygen saturation of ≤80% were similar in both groups. Levels of hsTrop T and NT-proBNP did not differ significantly before and after sleep but NT-proBNP levels were significantly higher in patients suffering from OSA and CAD compared to patients with OSA alone. No significant ST depression was found at the time of oxygen saturation nadir in either group. Despite the fact that patients with untreated OSA and coexisting CAD experienced severe nocturnal hypoxemia, we were unable to detect myocardial ischemia or myocyte necrosis based on significant ST segment depression or elevation of hsTrop T and NT-proBNP, respectively.

N-terminal pro-B-type natriuretic peptide variability in stable dialysis patients

BACKGROUND AND OBJECTIVES

Monitoring N-terminal pro-B-type natriuretic peptide (NT-proBNP) may be useful for assessing cardiovascular risk in dialysis patients. However, its biologic variation is unknown, hindering the accurate interpretation of serial concentrations. The aims of this prospective cohort study were to estimate the within- and between-person coefficients of variation of NT-proBNP in stable dialysis patients, and derive the critical difference between measurements needed to exclude biologic and analytic variation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Fifty-five prevalent hemodialysis and peritoneal dialysis patients attending two hospitals were assessed weekly for 5 weeks and then monthly for 4 months between October 2010 and April 2012. Assessments were conducted at the same time in the dialysis cycle and entailed NT-proBNP testing, clinical review, electrocardiography, and bioimpedance spectroscopy. Patients were excluded if they became unstable.

RESULTS

This study analyzed 136 weekly and 113 monthly NT-proBNP measurements from 40 and 41 stable patients, respectively. Results showed that 22% had ischemic heart disease; 9% and 87% had left ventricular systolic and diastolic dysfunction, respectively. Respective between- and within-person coefficients of variation were 153% and 27% for weekly measurements, and 148% and 35% for monthly measurements. Within-person variation was unaffected by dialysis modality, hydration status, inflammation, or cardiac comorbidity. NT-proBNP concentrations measured at weekly intervals needed to increase by at least 46% or decrease by 84% to exclude change due to biologic and analytic variation alone with 90% certainty, whereas monthly measurements needed to increase by at least 119% or decrease by 54%.

CONCLUSIONS

The between-person variation of NT-proBNP was large and markedly greater than within-person variation, indicating that NT-proBNP testing might better be applied in the dialysis population using a relative-change strategy. Serial NT-proBNP concentrations need to double or halve to confidently exclude change due to analytic and biologic variation alone.

Utility of point-of-care testing of natriuretic peptides (brain natriuretic peptide and n-terminal pro-brain natriuretic peptide) in the emergency department

Rapid and accurate diagnosis of a patient with an acute disease is a challenge for emergency physicians. Natriuretic peptides have emerged as important tools for diagnosis, risk stratification and therapeutic decision making for some categories of emergency patients. Brain natriuretic peptide (BNP) is a member of a four natriuretic peptides family that shares a common 17-peptide ring structure. Atrial natriuretic peptide, C-natriuretic peptide (CNP), and D-type natriuretic peptide are the other natriuretic peptide, which share the same common 17-peptide ring structure. The N-terminal fragment of pro-BNP, N-terminal pro-brain natriuretic peptide (NT-proBNP) consists of 76 amino acids, which is biologically inert, while the active component BNP contains 32 amino acids. BNP and NT-proBNP are secreted in the plasma in equimolar quantities and are frequently used in the diagnosis of congestive heart failure, and distinguishing between patients with dyspnea of cardiac or pulmonary origin. Both natriuretic peptides have also been evaluated for use in the assessment and management of several other conditions including sepsis, cirrhosis of liver and renal failure. However, one should remember that the values of natriuretic peptides are affected by age and weight of the patients, and presence of several comorbidities such as chronic renal failure, type 2 diabetes mellitus, anemia, pulmonary embolism, and acute coronary syndrome. Values of these peptides also vary depending on the type of test used. The performance characteristics of these natriuretic peptides vary depending on the patients on whom they are used. Therefore determination of reference values for these peptides represents a challenge.

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.

Association between N-terminal pro-brain natriuretic peptide levels and contrast-induced nephropathy in patients undergoing percutaneous coronary intervention for acute coronary syndrome

BACKGROUND

Contrast-induced nephropathy (CIN) is associated with significantly increased morbidity and mortality after percutaneous coronary intervention (PCI). Patients with acute coronary syndrome (ACS) are at higher risk for CIN. N-terminal pro-brain natriuretic peptide (NT-proBNP) is closely linked to the prognosis as a strong predictor of both short- and long-term mortality in patients with ACS.

HYPOTHESIS

We hypothesized that NT-proBNP levels on admission can predict the development of CIN after PCI for ACS.

METHODS

A total of 436 patients (age 62.27 ± 13.01 years; 64.2% male) with ACS undergoing PCI enrolled in this study. Admission NT-proBNP levels were measured before PCI. Serum creatinine values were measured before and within 72 hours after the administration of contrast agents. Patients were divided into 2 groups: CIN group and no-CIN group. CIN was defined as an increase in serum creatinine level of ≥0.5 mg/dL or ≥25% above baseline within 72 hours after contrast administration.

RESULTS

CIN developed in 63 patients (14.4%). Baseline NT-proBNP levels were significantly higher in patients who developed CIN compared to those who did not develop CIN (median 774 pg/mL, interquartile range 177.4-2184 vs median 5159 pg/mL, interquartile range 2282-9677, respectively; P < 0.001). Multivariate analysis found that NT-proBNP (odds ratio [OR]: 3.448, 95% confidence interval [CI]: 1.394-8.474, P = 0.007) and baseline creatinine (OR: 6.052, 95% CI: 1.860-19.686, P = 0.003) were independent predictors of CIN.

CONCLUSIONS

Admission NT-proBNP level is an independent predictor of the development of CIN after PCI in ACS.

Value of N-terminal pro brain natriuretic peptide in predicting prognosis and severity of coronary artery disease in acute coronary syndrome

BACKGROUND

Measurement of N-terminal pro brain natriuretic peptide (NT-proBNP) in the evaluation of patients with acute coronary syndrome has appeared to be a useful prognostic marker of cardiovascular risk.

AIM OF THE WORK

To assess the in-hospital prognostic value of NT-proBNP in patients with acute coronary syndrome (ACS) and its relation to the severity of coronary artery disease.

PATIENTS AND METHODS

This study included 132 consecutive patients with ACS, 64 patients with unstable angina (UA), 46 patients with non-ST segment elevation myocardial infarction (NSTEMI), and 22 patients with ST segment elevation myocardial infarction (STEMI). ECG, echocardiography and pre and post coronary angiography measurement of troponin I, creatine kinase (Ck), C-reactive protein (CRP) and NT-proBNP were done. Patients were divided into two groups: Group A with NT-proBNP less than 474 pg/ml and Group B with NT-proBNP equal or more than 474 pg/ml.

RESULTS

There was a significant negative correlation between NT-proBNP and ejection fraction. Incidence of heart failure and duration of hospital stay were significantly higher in Group B (with NT-proBNP equal or more than 474 pg/ml) than Group A (with NT-proBNP less than 474 pg/ml). Moreover, there was a trend to an increased incidence of cardiogenic shock and mortality in Group B compared to Group A. The number of coronary vessels affected, severity of stenosis and proximal left anterior descending artery (LAD) disease were higher in Group B than in Group A. TIMI flow grade was significantly higher in Group A than in Group B.

CONCLUSION

NT-proBNP is a valuable marker for predicting prognosis and severity of coronary artery disease in patients with acute coronary syndrome.

Prognostic value of brain natriuretic peptide in patients with heart failure and reserved left ventricular systolic function

Brain natriuretic peptide (BNP) is used as a prognostic biomarker for patients with heart failure (HF) in clinical practice, however, the correlation between BNP levels and the prognosis of HF in patients with reserved left ventricular systolic function (RLVSF) is not clear. Thus, the aim of the present study was to evaluate the added value of BNP in the prognosis of HF patients with RLVSF. Inpatients with cardiovascular disease (mean age, 65.7 years; male, 790; female, 625) admitted to the Division of Cardiology at Jinshan Hospital of Fudan University (Shanghai, China) between June 2006 and December 2009 underwent follow-up examinations. Plasma BNP levels were analyzed and measurements of the left ventricular ejection fraction (LVEF) were performed by echocardiography. Evaluations of the patients with HF were performed according to the New York Heart Association (NYHA) classification system. The duration of the follow-up period ranged between 21 and 63 months (average duration, 35.8 months) and key events included cardiovascular mortality, readmission due to cardiovascular disease or mortality due to other reasons. Survival times decreased with increasing BNP levels in all the follow-up patients (Spearman's ρ, -0.1877; P<0.0001). Among the 1,415 patients, 1,312 underwent echocardiographic detection. A total of 395 patients with NYHA classes II-IV and a LVEF ≥45% were selected. The incidence of compound endpoint events was significantly higher in the patients that had BNP levels of >100 pg/ml when compared with the patients that had BNP levels of ≤100 pg/ml (37.07 vs. 23.93%; relative risk, 1.55); consequently the survival times were significantly reduced (P=0.0039). A negative correlation was identified between the BNP levels and the survival times in these patients (Spearman's ρ, -0.1738; P=0.0005). These results indicated that the levels of BNP may be used to predict the prognosis of patients with cardiovascular disease. The prognoses of patients with higher BNP levels were worse compared with the patients with lower BNP levels. Furthermore, significant correlations were confirmed in the HF patients with RLVSF.

The severity of coronary artery disease and reversible ischemia revealed by N-terminal pro-brain natriuretic peptide in patients with unstable angina and preserved left ventricular function

The association between the levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and the severity of coronary artery disease (CAD) diagnosed by coronary angiography and other approaches has been investigated. The clinical application of NT-proBNP is restricted by the drawbacks of these techniques now available in screening out patients who need intensive or conservative treatment. Fractional flow reserve (FFR) is superior to coronary angiography and other functional indicators. Accordingly, we designed to investigate the association between NT-proBNP and myocardial ischemia from the perspective of anatomy and physiology in patients with unstable angina and preserved left ventricular function. Plasma samples were collected from 110 patients and NT-proBNP levels were measured by radioimmunoassay. The severity of coronary artery stenosis in patients was measured by coronary angiography and FFR. Stenosis ≥50% in the left main artery or stenosis of 70%, and fractional flow reserve (FFR) ≤0.80 in one or more coronary branches with diameter ≥2mm were defined as "positive", which require revascularization. NT-proBNP levels increased progressively between patients with negative and positive angiographic results (p<0.05), and between FFR-negative and FFR-positive patients (p<0.05). A significant correlation was observed between logNT-proBNP and logGS (GS=Gensini score, p<0.001). NT-proBNP level serves as a predictor of positive results of angiographic stenosis and FFR, with the area under the receiver operating characteristic curve being 0.697 and 0.787, respectively. NT-proBNP levels are correlated with the severity of anatomic coronary obstruction and inducible myocardial ischemia, but NT-proBNP per se is insufficient to identify clinically significant angiographic and physiological stenoses.

Physiology of natriuretic peptides: The volume overload hypothesis revisited

The discovery of the natriuretic peptide system in the early 1980s aroused great interest among clinical cardiologists. The heart was not a mechanical pump alone, but also an endocrine organ that had powerful effects on blood circulation. Natriuretic peptides caused both natriuresis and diuresis, and they responded to a volume overload which caused either stretch or pressure on the heart. As a result, the findings led to the conclusion that the human body had a hormone with effects similar to those of a drug which treats high blood pressure. Later, it became evident that the volume contraction was fortified by extrarenal plasma shift. Here, a hypothesis is presented in which the role of natriuretic peptides is to regulate oxygen transport as the volume contraction leads to hemoconcentration with an increased oxygen-carrying capacity. Wall stress, either chemical or mechanical, changes the oxygen gradient of the myocardium and affects the diffusion of oxygen within a myocyte. In support of this hypothesis, hypoxia-response elements have been found in both the atrial natriuretic peptide and the brain natriuretic peptide genes.

The time-course changes of NT-proBNP and tissue Doppler indices in patients undergoing mitral valve replacement

Background

In severe mitral regurgitation, a subset of patients who are asymptomatic may develop left ventricular decompensation before changes in echocardiographic parameters become evident. Since N-terminal brain natriuretic peptide (NT-proBNP) is used to detect early heart failure, we hypothesised that NT-proBNP would be activated in patients with mitral regurgitation.

Methods

Patients submitted to surgery were prospectively evaluated over eight months in the Department of Cardiology at Inkosi Albert Luthuli Central Hospital. Control patients with severe mitral regurgitation were obtained from the outpatient clinic. In order to define their value in identifying left ventricular decompensation, NT-proBNP levels and tissue Doppler imaging (TDI) indices were simultaneously measured and compared with conventional echocardiographic indices at baseline and this was repeated at one week and at six weeks after valve replacement.

Results

Mean NT-proBNP levels were markedly elevated pre-operatively in all surgical cases compared to controls (p = 0.0001). The diastolic E-mitral/E-annulus ratio, measured using TDI, was higher in the study group, indicating higher left ventricular filling pressure present in the study group. NT-proBNP levels increased further at one week after surgery and subsided at the six-week follow-up visit to levels similar to the control group. The TDI diastolic ratio also decreased at one week, and increased slightly again at the six-week follow up. These changes were accompanied by significant reduction in left atrium and left ventricular chamber dimensions with an increase in the ejection fraction from one to six weeks.

Conclusion

Marked differences in mean NT-proBNP levels and TDI ratios between the study and control groups suggest that using TDI and NT-proBNP assays may detect covert left ventricular decompensation.

Clinical outcome of patients treated with an early invasive strategy after out-of-hospital cardiac arrest

Little is known about the impact of early invasive treatment in patients following out-of-hospital cardiac arrest (OHCA). The present study investigated the clinical characteristics and long-term prognosis of 1254 patients with suspected acute coronary syndrome, including 65 with OHCA who underwent successful cardiopulmonary resuscitation (CPR) and 1189 patients who did not require CRP. All patients underwent immediate coronary angiography even if clear signs of myocardial infarction (MI) were absent. The incidence of ST-elevation and non-ST-elevation MI did not differ between the two groups. Cardiac biomarkers were significantly higher in CPR patients despite a shorter period from symptom onset to admission. The 6-month mortality rate was 29% in the CPR group and 4% in the non-CPR group, with > 90% of fatalities occurring ≤ 3 weeks after admission. In summary, early invasive treatment leads to a considerably reduced mortality and improved prognosis in patients after OHCA.

High sensitivity troponin T provides useful prognostic information in non-acute chest pain

OBJECTIVE

To evaluate the prognostic value of high-sensitivity troponin T (hs-cTnT) in patients who present to General Practitioners (GPs) with non-acute chest pain.

DESIGN, SETTING AND PATIENTS

A total of 625 patients who were referred by their GPs to a regional Rapid Access Chest Pain Clinic in Tayside, Scotland were consented and recruited. Diamond-Forrester pretest probability of coronary artery disease (CAD) was used to select patients with intermediate and high-pretest probability. Hs-cTnT and B-type Natriuretic Peptide (BNP) were measured and final diagnosis recorded. Twelve-month follow-up for cardiac events and hospital admission data was collected. Sensitivity, specificity, positive predictive value and negative predictive value (NPV), for both prognosis and diagnosis, were produced using various pre-specified cut-off values for hs-cTnT and BNP.

RESULTS

A total of 579 patients were included in the final analysis. Of these, 477 had intermediate/high-pretest probability of CAD. A total of 431 (90.4%) of patients had a hs-cTnT ≤14 ng/l. In this study, hs-cTnT of 14 ng/l was the best cut-off for ruling out if a patient would have an admission for cardiac chest pain in the following 12 months (specificity 90%, NPV 91.4%). It performed well as a predictor of a subsequent negative diagnosis of cardiac chest pain with a specificity of 92.4% and NPV of 83.5%.

CONCLUSIONS

Hs-cTnT, at the same level currently used in clinical practice as a diagnostic cut-off for myocardial infarction and acute coronary syndromes, is also a clinically-meaningful indicator for further 12-month cardiac chest pain hospital admissions in patients with non-acute chest pain referred to chest pain clinics by GPs.

Association of NT-proBNP and multiple biomarkers with severity of angiographic coronary artery disease in diabetic and pre-diabetic Chinese patients

BACKGROUND

Little is known about the plasma levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), and the relationship between the severity of coronary heart disease (CHD) with NT-proBNP and multiple biomarkers in diabetic and pre-diabetic patients, compared to individuals with normal glucose levels.

METHODS

Four hundred and fifteen consecutive Chinese patients of both sexes were assigned to three groups on the basis of the new hemoglobin (Hb) A1c (HbA1c) cut-off points for diagnosis of diabetes and pre-diabetes. The three groups were divided into tertiles according to NT-proBNP, hs-CRP, cystatin C, and troponin T levels. Gensini scores were compared among the three groups and biomarker tertiles. Receiver operating characteristic (ROC) curves were used to obtain the angiographic CHD cut-off points for each biomarker. Stepwise multivariate linear correlation analysis was applied to examine the association between the severity of CHD and biomarker levels.

RESULTS

Gensini scores increased with increasing biomarker tertile levels and HbA1c. Gensini scores were significantly different in the middle and upper NT-proBNP tertiles of the diabetic, pre-diabetic and control groups. NT-proBNP had the highest positive and negative predictive values and area under the curve for CHD. Only NT-proBNP was identified as an independent variable for Gensini score.

CONCLUSIONS

Plasma NT-proBNP may be an important biomarker to evaluate the severity of CHD and screen for CHD in diabetic or pre-diabetic patients.

B-type natriuretic peptide in the early diagnosis and risk stratification of acute chest pain

BACKGROUND

Myocardial ischemia is a strong trigger of B-type natriuretic peptide (BNP) release. As ischemia precedes necrosis in acute myocardial infarction, we hypothesized that BNP might be useful in the early diagnosis and risk stratification of patients with acute chest pain.

METHODS

In a prospective, international multicenter study, BNP was measured in 1075 unselected patients with acute chest pain. The final diagnosis was adjudicated by 2 independent cardiologists. Patients were followed long term regarding mortality.

RESULTS

Acute myocardial infarction was the adjudicated final diagnosis in 168 patients (16%). BNP levels at presentation were significantly higher in acute myocardial infarction as compared with patients with other diagnoses (median 224 pg/mL vs. 56 pg/mL, P <.001). The diagnostic accuracy of BNP for the diagnosis of acute myocardial infarction as quantified by the area under the receiver operating characteristic curve (AUC) (0.74; 95% confidence interval [CI], 0.70-0.78) was lower compared with cardiac troponin T at presentation (AUC 0.88; 95% CI, 0.84-0.92; P <.001). Cumulative 24-month mortality rates were 0.5% in the first, 2.1% in the second, 7.0% in the third, and 22.9% in the fourth quartile of BNP (P <.001). BNP predicted all-cause mortality independently of and more accurately than cardiac troponin T: AUC 0.81 (95% CI, 0.76-0.86) versus AUC 0.70 (95% CI, 0.62-0.77; P <.001). Net reclassification improvement for BNP was 0.10 (P=.04), and integrated discrimination improvement 0.068 (P=.01).

CONCLUSIONS

BNP accurately predicts mortality in unselected patients with acute chest pain independently of and more accurately than cardiac troponin T, but does not seem to help in the early diagnosis of acute myocardial infarction.

Screening for left ventricular hypertrophy in patients with type 2 diabetes mellitus in the community

BACKGROUND

Left ventricular hypertrophy (LVH) is a strong predictor of cardiovascular disease and is common among patients with type 2 diabetes. However, no systematic screening for LVH is currently recommended for patients with type 2 diabetes. The purpose of this study was to determine whether NT-proBNP was superior to 12-lead electrocardiography (ECG) for detection of LVH in patients with type 2 diabetes.

METHODS

Prospective cross-sectional study comparing diagnostic accuracy of ECG and NT-proBNP for the detection of LVH among patients with type 2 diabetes. Inclusion criteria included having been diagnosed for > 5 years and/or on treatment for type 2 diabetes; patients with Stage 3/4 chronic kidney disease and known cardiovascular disease were excluded. ECG LVH was defined as either the Sokolow-Lyon or Cornell voltage criteria. NT-proBNP level was measured using the Roche Diagnostics Elecsys assay. Left ventricular mass was assessed from echocardiography. Receiver operating characteristic curve analysis was carried out and area under the curve (AUC) was calculated.

RESULTS

294 patients with type 2 diabetes were recruited, mean age 58 (SD 11) years, BP 134/81 ± 18/11 mmHg, HbA 1c 7.3 ± 1.5%. LVH was present in 164 patients (56%). In a logistic regression model age, gender, BMI and a history of hypertension were important determinants of LVH (p < 0.05). Only 5 patients with LVH were detected by either ECG voltage criteria. The AUC for NT-proBNP in detecting LVH was 0.68.

CONCLUSIONS

LVH was highly prevalent in asymptomatic patients with type 2 diabetes. ECG was an inadequate test to identify LVH and while NT-proBNP was superior to ECG it remained unsuitable for detecting LVH. Thus, there remains a need for a screening tool to detect LVH in primary care patients with type 2 diabetes to enhance risk stratification and management.