Natriuretic peptides in patients with aortic stenosis

N-terminal pro-B-type natriuretic peptide levels pre-transcatheter aortic valve implantation and relationship with long-term outcomes

Background

Blood levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) has been suggested as a future guidance tool for the selection of patients for aortic valve replacement. This study aimed to examine how levels of NT-proBNP pre-transcatheter aortic valve implantation (TAVI) is associated with one-year rates of heart failure (HF) admission and mortality following TAVI.

Methods

With Danish nationwide registries, we identified all patients undergoing TAVI from 2014 to 2021 who had at least one recorded NT-pro-BNP measurement within one year before TAVI. Patients were compared by quartiles of pre-TAVI NT-proBNP: quartile 4 (high NT-proBNP group) vs quartile 1-3 (low NT-proBNP group). Comparisons of all-cause mortality and HF-admissions were conducted using Kaplan-Meier analysis, cumulative incidence, and Cox analysis, as appropriate.

Results

We identified 1,140 patients undergoing first-time TAVI with a recorded NT-pro-BNP; 846 (74.2 %) with a low NT-proBNP (<420 pmol/L) (55.0 % male, median age 81 year) and 294 (25.8 %) with a high NT-proBNP (≥420 pmol/L) (53.1 % male, median age 82 year). A high versus low NT-proBNP was associated with increased one-year cumulative incidence of HF-admissions (9.1 % vs. 23.1 %, adjusted HR 2.00 [95 % CI, 1.40-2.85]) and all-cause mortality (6.0 % vs. 14.6 %, adjusted HR 1.95 [95 % CI: 1.24-3.07]). A high NT-proBNP was associated with higher rates of outcomes irrespective of previously known atrial fibrillation, HF, chronic kidney disease, and hypertension.

Conclusion

In patients undergoing TAVI, a baseline NT-proBNP ≥ 420 pmol/L was associated with increased one-year rates of HF-admission and mortality post-TAVI and may be utilized to identify a high-risk population.

Early Intervention in Asymptomatic Aortic Stenosis: What Are We Waiting For?

Aortic stenosis (AS) contributes to significant cardiovascular morbidity and mortality worldwide, and the natural history from symptoms to ventricular decompensation, heart failure, and death has been well documented. For more than 2 decades, technologies including imaging and biomarkers have shown a promising ability to detect myocardial damage associated with AS before symptoms arise. Current treatment guidelines rely heavily on symptoms or ventricular decompensation as triggers for aortic valve intervention. There is increasing appreciation of the relationship between myocardial damage due to AS before the emergence of symptoms, and a number of published randomised trials suggest a benefit to early intervention in asymptomatic AS, with additional trials actively enrolling. Future treatment paradigms may incorporate early detection of ventricular damage by noninvasive new technologies as triggers for asymptomatic intervention. Enthusiasm for early aortic valve replacement should be tempered by consideration of the competing risks of early valve intervention, but an increasing preponderance of evidence continues to suggest that earlier intervention in AS is warranted.

Plasma N-terminal pro-B-type natriuretic peptide in the detection of aortic valve stenosis

BACKGROUND

Systolic murmur suggestive of aortic valve origin is a common accidental finding, particularly in the elderly. Usually, it is due to aortic stenosis (AS) or aortic sclerosis (ASc). Currently, echocardiography is used to differentiate AS from ASc. Plasma N-terminal (NT)-prohormone BNP (NT-proBNP) is known to correlate with the severity of AS. We assessed whether NT-proBNP separates AS from ASc.

METHODS

The study population consisted of three groups: AS (n = 87, age 77 ± 7 years), ASc (n = 76, age 72 ± 10 years), and healthy controls (n = 101, age 55 ± 10 years). All subjects underwent transthoracic echocardiography and measurement of plasma NT-proBNP. Patients with diseases known to increase NT-proBNP were excluded.

RESULTS

The crude plasma NT-proBNP (median; IQR) in AS patients (413; 165-1055 ng/l) was significantly higher compared to ASc patients (96; 53-237 ng/l, p < 0.001) and healthy controls (50; 29-76 ng/l, p < 0.001). After adjusting for the confounding factors (age, coronary artery disease, renal function and diastolic blood pressure), plasma NT-proBNP remained significantly higher in AS patients as compared to ASc (p < 0.002) and controls (p < 0.0001). In the receiver-operating characteristic curve for NT-proBNP to identify AS from ASc and controls, the area under the curve was 0.878 with optimal cutoff of 115 ng/l. In addition, using 115 ng/l to separate AS from ASc yielded sensitivity of 0.885, and negative predictive value of 0.808.

CONCLUSIONS

NT-proBNP was sensitive to identify AS and useful to rule out AS in patients with systolic murmur in the left ventricular outflow tract provided the patient does not have coexisting disease known to impact NT-proBNP.

B-type natriuretic peptide and N-terminal Pro-B-type natriuretic peptide in severe aortic stenosis: a comprehensive literature review

B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-pro BNP) are cardiac biomarkers that are released in response to increased ventricular and atrial wall stress. Aortic stenosis (AS) leads to hemodynamic changes and left ventricular hypertrophy and may be associated with natriuretic peptide levels. Several studies have shown that increased natriuretic peptide levels are correlated with AS severity and can predict the need for intervention. It can be useful in risk stratification, monitoring follow-up, and predicting cardiovascular outcomes of patients with severe AS. This paper aims to summarize the evidence of the role of BNP and NT-pro BNP in AS, before and after intervention.

The association of left ventricular histologically verified myocardial fibrosis with pulmonary hypertension in severe aortic stenosis

OBJECTIVES

To evaluate the association between histologically verified left ventricular (LV) myocardial fibrosis (MF) and its bio- and functional markers with pulmonary hypertension (PH) in severe aortic stenosis (AS).

METHODS

About 34 patients with isolated severe AS underwent 2D echocardiography, cardiac magnetic resonance (CMR) imaging, and plasma NT-proBNP evaluation before aortic valve replacement (AVR). LV measurements were analyzed by CMR and LV strain using feature tracking software (Medis Suite QStrain 2.0). Myocardial biopsy sampled at the time of AVR was assessed by a histomorphometric analysis. PH was defined as pulmonary artery systolic pressure (PASP) ⩾ 45 mm Hg.

RESULTS

Patients with severe AS and PH (mean PASP 53 ± 3.7 mm Hg) had higher extent of diffuse MF versus patients without PH (12 (10.4-12.7)% vs 6.6 (4.6-8.2)% (p = 0.00)). The extent of diffuse MF correlated with LV dilatation (r = 0.7, p = 0.02), indices of LV dysfunction (lower ejection fraction (r = -0.6, p < 0.001), global longitudinal (r = -0.5, p = 0.02) and circumferential strain (r = -0.5, p = 0.05), elevated NT-proBNP (r = 0.5, p = 0.005) and elevated PASP (r = 0.6, p < 0.001)). Histological MF > 10% (AUC 94.9%), LV global longitudinal strain > -15.5% (AUC 86.3%), and NT-proBNP > 2090 ng/l (AUC 85.1%) were independent predictors of PH in severe AS.

CONCLUSIONS

The extent of diffuse myocardial fibrosis in combination with reduced longitudinal left ventricular strain and increased plasma levels of NT-proBNP relates to pulmonary hypertension in severe aortic stenosis.

The relation between average 1-year home blood pressure and the change in pro-BNP and left ventricle mass index

BACKGROUND

The purpose of this investigation was to examine the association between average 1-year home blood pressure and the change in left ventricular mass index (LVMI) and pro-brain natriuretic peptide (BNP) levels.

METHODS

This prospective study was a subgroup analysis of lifestyle intervention using mobile technology in patients with high cardiovascular risk: a pragmatic randomized clinical Trial (LIGHT). In total, 242 patients were stratified into tertiles according to their average 1-year home blood pressure.

RESULTS

Patients grouped into the tertile 3 (T3) had a lower 1-year mean, SBP and DBP. The T3 group had a 2.1 times higher rate of decrease in pro-BNP and a 1.6 times higher rate of decrease in LVMI compared with T1, compared with the reference group. The area under curve (AUC) value of average 1-year home blood pressure was higher than that of mean SBP or DBP. (AUC, 0.75 vs. AUC, 0.70 vs. AUC, 0.69, respectively). Spearman rank correlation demonstrated that average 1-year home blood pressure had a correlation with Δpro-BNP and ΔLVMI.

CONCLUSION

The present study showed that average 1-year home blood pressure may have a significant association with a decrease in LVMI and pro-BNP. Our study appears to be the first to evaluate the association between average 1-year home blood pressure and the change in LVMI and pro-BNP.

Associations of cardiac injury biomarkers with risk of peripheral artery disease: The Multi-Ethnic Study of Atherosclerosis

INTRODUCTION

We investigated the associations of high-sensitivity cardiac Troponin T (hs-cTnT) and N-terminal pro B-type natriuretic peptide (NT-proBNP) levels with risk of developing clinical peripheral artery disease (PAD) or a low ankle-brachial index (ABI).

METHODS

Hs-cTnT and NT-proBNP were measured in 6692 and 5458 participants respectively without baseline PAD between 2000 and 2002 in the Multi-ethnic Study of Atherosclerosis. A significant number also had repeat biomarker measurement between 2004 and 2005. Incident clinical PAD was ascertained through 2017. Incident low ABI, defined as ABI <0.9 and decline of ≥0.15 from baseline, was assessed among 5920 eligible individuals who had an ABI >0.9 at baseline and at least one follow-up ABI measurement 3-10 years later. Multivariable Cox proportional hazards and logistic regression modeling were used to determine the association of these biomarkers with clinical PAD and low ABI, respectively.

RESULTS

Overall, 121 clinical PAD and 118 low ABI events occurred. Adjusting for demographic and clinical characteristics, each log unit increment in hs-cTnT and NT-proBNP was associated with a 30% (adjusted hazard ratio (HR) 1.3, 95% confidence interval (CI): 1.1, 1.6) and 50% (HR) 1.5, 95% CI: 1.2, 1.8) higher risk of clinical PAD respectively. No significant associations were observed for incident low ABI. Change in these biomarkers was not associated with either of the PAD outcomes.

CONCLUSIONS

NT-proBNP and hs-cTnT are independently associated with the development of clinical PAD. Further study should determine whether these biomarkers can help to better identify those at higher risk for PAD.

A review of biosensors for the detection of B-type natriuretic peptide as an important cardiovascular biomarker

Heart disease, as the most serious threat to human health globally, is responsible for rising mortality rates, largely due to lifestyle and diet. Unfortunately, the main problem for patients at high risk of heart disease is the validation of prognostic tests. To this end, the detection of cardiovascular biomarkers has been employed to obtain pathological and physiological information in order to improve prognosis and early-stage diagnosis of chronic heart failure. Short-term changes in B-type natriuretic peptide are known as a standard and important biomarker for diagnosis of heart failure. The most important problem for detection is low concentration and short half-life in the blood. The normal concentration of BNP in blood is less than 7 nM (25 pg/mL), which increases significantly to more than 80 pg/mL. Therefore, the development of new biosensors with better sensitivity, detection limit, and dynamic range than current commercial kits is urgently needed. This review classifies the biosensors designed for detection of BNP into electrochemical, optical, microfluidic, and lateral-flow immunoassay techniques. The review clearly demonstrates that a variety of immunoassay, aptasensor, enzymatic and catalytic nanomaterials, and fluorophores have been successfully employed for detection of BNP at low attomolar ranges. Dtection of B-type natriuretic peptide with biosensors.

Blood biomarkers in patients with bicuspid aortic valve disease

BACKGROUND

Patients with a bicuspid aortic valve (BAV) are at risk of developing valve deterioration and aortic dilatation. We aimed to investigate whether blood biomarkers are associated with disease stage in patients with BAV.

METHODS

Serum levels of high sensitivity C-reactive protein (hsCRP), high sensitivity troponin T (hsTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and total transforming growth factor-beta 1 (TGF-ß1) were measured in adult BAV patients with valve dysfunction or aortic pathology. Age-matched general population controls were included for TGFß-1 measurements. Correlation analyses and multivariable linear regression were used to determine the association between (2log-transformed) biomarker levels and aortic valve regurgitation, aortic valve stenosis, aortic dilatation, or left ventricular function.

RESULTS

hsCRP and hsTnT were measured in the total group of 183 patients (median age 34 years, 25th-75th percentile 23-46), NT-proBNP in 162 patients, and TGF-ß1 beta in 108 patients. Elevated levels of NT-proBNP were found in 20% of the BAV patients, elevated hsTnT in 6%, and elevated hsCRP in 7%. Higher hsTnT levels were independently associated with aortic regurgitation [odds ratio per doubling (OR_2log) 1.34, 95% CI 1.01;1.76] and higher NT-proBNP levels with aortic valve maximal velocity (ß_2log 0.17, 95%CI 0.07;0.28) and aortic regurgitation (OR_2log 1.41, 95%CI 1.11;1.79). Both BAV patients with (9.9 ± 2.7 ng/mL) and without aortic dilatation (10.4 ± 2.9 ng/mL) showed lower TGF-ß1 levels compared to general population controls (n = 85, 11.8 ± 3.2 ng/mL).

CONCLUSIONS

Higher NT-proBNP and hsTNT levels were associated with aortic valve disease in BAV patients. TGF-ß1 levels were lower in BAV patients than in the general population, and not related to aortic dilatation. Longitudinal data are needed to further investigate the prognostic value of biomarkers in these patients.

Relationship between B-type natriuretic peptide and invasive haemodynamics in patients with severe aortic valve stenosis

AIMS

In patients with aortic stenosis (AS), B-type natriuretic peptide (BNP) is a prognostic marker. However, there is little information on the association between BNP and invasive haemodynamics in AS. The aim of the present study was to assess the hitherto not well-defined relationship between BNP and invasive haemodynamics in patients with severe AS undergoing aortic valve replacement (AVR) with a view to understand the link between high BNP and poor prognosis in these patients. In particular, we were interested in the association between BNP and combined pre-capillary and post-capillary pulmonary hypertension (CpcPH).

METHODS AND RESULTS

BNP was measured in 252 patients (age 74 ± 10 years, 58% male patients) with severe AS [indexed aortic valve area 0.4 ± 0.1 cm² /m² and left ventricular ejection fraction (LVEF) 57 ± 12%] the day before cardiac catheterization. Patients were followed for a median (interquartile range) period of 3.1 (2.3-4.3) years after surgical (n = 157) or transcatheter (n = 95) AVR. The prevalence of CpcPH (mean pulmonary artery pressure ≥ 25 mmHg, mean pulmonary artery wedge pressure > 15 mmHg, and pulmonary vascular resistance > 3 Wood units) was 13%. The median BNP plasma concentration was 188 (78-452) ng/L. The indexed aortic valve area was similar across BNP quartiles (P = 0.21). Independent predictors of higher BNP (ln transformed) included lower haemoglobin (beta = -0.18; P < 0.001), lower LVEF (beta = -0.20; P < 0.001), more severe mitral regurgitation (beta = 0.20; P < 0.001), higher mean pulmonary artery wedge pressure (beta = -0.37; P < 0.001), and higher pulmonary vascular resistance (beta = 0.21; P < 0.001). In a multivariate model with CpcPH rather than its haemodynamic components, CpcPH was independently associated with higher BNP (0.21; P < 0.001). Higher ln BNP was associated with higher mortality [hazard ratio 1.90 (95% confidence interval 1.33-2.71); P < 0.001] in the univariate analysis. Patients in the third and fourth BNP quartiles had a more than six-fold risk of death compared with patients in the first and second quartiles [hazard ratio 6.29 (95% confidence interval 1.86-21.27); P = 0.003]. In the multivariate analysis, lower LVEF [hazard ratio 0.96 (95% confidence interval 0.94-0.99) per 1% increase; P = 0.01] and CpcPH [hazard ratio 4.58 (95% confidence interval 1.89-11.09); P = 0.001] but not BNP were independently associated with mortality. The areas under the receiver operator characteristics curve for BNP for the prediction of CpcPH and mortality were 0.88 and 0.74, respectively.

CONCLUSIONS

In patients with severe AS, higher BNP is a marker of the presence of CpcPH and its contributors. The association between BNP and such an adverse haemodynamic profile at least in part explains the ability of BNP to predict long-term post-AVR mortality.

Low and elevated B-type natriuretic peptide levels are associated with increased mortality in patients with preserved ejection fraction undergoing transcatheter aortic valve replacement: an analysis of the PARTNER II trial and registry

Aims

B-type natriuretic peptide (BNP) is a cardiac neurohormone that is secreted in response to ventricular volume expansion and pressure overload. There are conflicting data regarding the association between BNP levels and outcomes after transcatheter aortic valve replacement (TAVR). We therefore sought to assess the association between baseline BNP and adverse outcomes in patients with symptomatic, severe aortic stenosis (AS), and left ventricular ejection fraction (LVEF) ≥50%, undergoing TAVR in the PARTNER 2 Trial and Registry.

Methods and results

A total of 1782 patients were included in the analysis, and BNP was evaluated both as a continuous log-transformed value and by a priori categories: low (&lt;50 pg/mL), normal (≥50 and &lt;100 pg/mL), moderately elevated (≥100 and &lt;400 pg/mL), or markedly elevated (≥400 pg/mL). Clinical outcomes from discharge to 2 years were compared between patients according to their baseline BNP level, using Kaplan–Meier event rates and multivariable Cox proportional hazards regression models. After adjustment, spline curves revealed a non-linear association between log-transformed BNP and all-cause and cardiovascular mortality in which both the lowest and highest values were associated with increased mortality. Two-year all-cause mortality rates for those with low (n = 86), normal (n = 202), moderately elevated (n = 885), and markedly elevated (n = 609) baseline BNP were 20.0%, 9.8%, 17.7%, and 26.1%, respectively. In adjusted models, compared to a normal baseline BNP, low [adjusted hazard ratio (HR) 2.6, 95% confidence interval (CI) 1.3–5.0, P-value 0.005], moderately elevated (adjusted HR 1.6, 95% CI 1.0–2.6, P-value 0.06), and markedly elevated (adjusted HR 2.1, 95% CI 1.3–3.5, P-value 0.003) BNP were associated with increased all-cause mortality, driven by cardiovascular mortality.

Conclusions

In a large cohort of patients with severe symptomatic AS and preserved LVEF undergoing TAVR, all-cause and cardiovascular mortality rates at 2 years were higher in patients with low and markedly elevated BNP levels.

Clinical Trial Registration

https://clinicaltrials.gov/ unique identifier #NCT01314313, #NCT02184442, #NCT03222128, and #NCT03222141.

Nt-ProBNP Discriminatory Role Between Symptomatic and Asymptomatic Patients with Severe Valvular Aortic Stenosis

Background: The aim was to evaluate the Nt-proBNP discriminatory role between symptomatic and asymptomatic patients with severe aortic stenosis.

Methods: 187 patients with severe valvular aortic stenosis, with normal EF > 50%, were included, 61 asymptomatic and 126 symptomatic. We used clinical, laboratory (Nt-proBNP) and echocardiographic parameters. Endpoints of monitoring (occurrence of event) were: the onset of symptoms in asymptomatic patients and death in both groups.

Results: The symptomatic group with severe AS had a significantly higher means of Nt-proBNP, in comparison with the asymptomatic group. Nt-proBNP was a significant predictor for the risk of event occurrence (HR 1.4). In the group of severe AS without CAD (n = 101), the subgroup with Nt-proBNP above the cut-off value, took significantly higher percentage of patients with chest pain, fatigue and syncope. In the group with Nt-proBNP above the cut-off value, we had a significantly higher percentage of patients with severe AS without CAD, compared to those with CAD (n = 142). Nt-proBNP was negatively correlated with AVA and LVEF, whether the positive correlation was expressed for: LVEDd, LVEDs, IVSd, AV_Vmax, AV_MaxGrad, LVM and LA. Patients with Nt-proBNP above the cut-off, had a significantly lower event free survival, compared to patients with Nt-proBNP below the cut-off (n = 187; n = 101).

Conclusion: The Nt-proBNP cut-off> 460 pg/ml was confirmed as a useful tool in the determination of event free survival in patients with severe AS. Nt-proBNP not only had relevance in the assessment of the severity of the disease, but also was a significant predictor for the risk of event occurrence.

Relation of N-Terminal Pro-B-Type Natriuretic Peptide and Left Ventricular Diastolic Function to Exercise Tolerance in Patients With Significant Valvular Heart Disease and Normal Left Ventricular Systolic Function

An association between N-terminal prohormone brain natriuretic peptide (NT-proBNP) and exercise tolerance in patients with valvular heart disease (VHD) has been suggested; however, there are few data available regarding this relation. The aim of this study is to evaluate the correlation between exercise tolerance and NT-proBNP in patients with asymptomatic or mildly symptomatic significant VHD and normal left ventricular ejection fraction (LV EF). A total of 96 patients with asymptomatic or mildly symptomatic VHD and normal LV EF (≥50%) underwent cardiopulmonary exercise echocardiography. NT-proBNP levels were determined at baseline and after exercise in 3 hours. Patients were divided in 2 groups based on lower (<26 ml/kg/min, n = 47) or higher (≥26 ml/kg/min, n = 49) peak oxygen consumption (VO₂) as a representation of exercise tolerance. In the 2 groups, after adjusting for age and gender, the NT-proBNP level after exercise in 3 hours, left atrial volume index before exercise, right ventricular systolic pressure before exercise, E velocity after exercise, and E/e' ratio after exercise varied significantly. In addition, peak VO₂ was inversely related to NT-proBNP before (r = -0.352, p <0.001) and after exercise (r = -0.351, p <0.001). The NT-proBNP level before exercise was directly related to the left atrial volume index, E/e' ratio, and right ventricular systolic pressure before and after exercise. NT-proBNP after exercise was also directly related to the same parameters. NT-proBNP levels both before and after exercise were higher in the group with lower exercise tolerance. In conclusion, through the correlation among exercise tolerance, NT-proBNP, and parameters of diastolic dysfunction, we demonstrated that diastolic dysfunction and NT-proBNP could predict exercise tolerance in patients with significant VHD and normal LV EF.

Changing concept in treatment of asymptomatic severe aortic stenosis and normal ejection fraction: time for biomarkers reappraisal

The uncertainty of whether/how to treat asymptomatic patients with isolated severe aortic stenosis and normal left ventricular ejection fraction is one of the most topical in cardiovascular medicine. Recently, the AVATAR trial: first ever randomized trial in the setting of aortic stenosis has been started in an attempt to adequately address this 'burning issue'. In light of this fact it is important to identify biomarkers which might help in risk stratification of these patients, not only in the referring physician's office during a routine exam, but also for preoperative patients scheduled for surgical replacement/transcatheter aortic valve implantation. This report is focusing on novel laboratory parameters which might be helpful in this risk stratification.

Evaluation of aortic stenosis: an update--including low-flow States, myocardial mechanics, and stress testing

Degenerative aortic stenosis (AS) is one of the most frequent valvular heart diseases in Western countries. Echocardiography plays a central role in the evaluation and management of patients with AS. To overcome the inherent inconsistencies between the echocardiographic parameters defining severe AS and to unify concepts, a new classification based on the interplay between flow and gradients has recently been adopted. Outcome studies of asymptomatic patients with preserved left ventricular ejection fraction (LVEF), as classified by this new approach, have shown that low-flow (LF) states are associated with poor outcome, that the classical normal-flow/high-gradient pattern has an intermediate outcome, while normal-flow/low-gradient severe AS seems to have an outcome comparable to moderate AS and such patients do not benefit from aortic valve replacement. Patients with LF/low-gradient severe AS with preserved LVEF, also known as "paradoxical LF/low-gradient AS," have the worst outcome and benefit greatly from surgical or percutaneous valve replacement, provided that severity is proven. In patients with LF/low-gradient and depressed LVEF, dobutamine stress echocardiography has an important role to distinguish severe from pseudo-severe AS and to assess surgical risk. Assessment of aortic valve calcium score, as well as computation of projected effective orifice aortic area at normal trans-valvular flow rates, has proved to be very useful to distinguish severe from pseudo-severe AS in LF/low-gradient AS with both reduced and preserved LVEF. Asymptomatic patients with normal flow/gradient should be submitted to an exercise test; exercise echocardiography can identify patients at increased risk when mean gradient increases by >18-20 mmHg and/or pulmonary arterial hypertension develops during exercise.

Clinical Applications of Natriuretic Peptides in Assessment of Valvular Heart Disease

Biomarkers such as natriuretic peptides (NPs) have evolving clinical utility beyond the scope of heart failure. The role of NPs in the management of valvular heart disease is a growing area of investigation. NPs have much potential in the assessment of asymptomatic patients with hemodynamically significant valvular lesions who have traditionally been excluded from consideration of surgical intervention. NPs also have a role in the risk stratification of these patients as well as in routine surveillance and monitoring. Together with echocardiographic data and functional status, NPs are being incorporated into the management of valvular heart disease. In this review we examine the evidence for the role of natriuretic peptides in assessment of VHD.

Comprehensive Risk Stratification of Japanese Patients With Aortic Stenosis--A Proposal of a New Risk Score From the CHART-2 Study

BACKGROUND

The risk of patients with aortic stenosis (AS) should be stratified not only by AS severity but also by comorbidities.

METHODS AND RESULTS

We aimed to develop a risk score for mortality in 412 patients with AS (pressure gradient ≥30 mmHg, mean age 74.9 years, male 52.4%) in the CHART-2 Study (n=10,219). During a 3-year follow-up, 73 (17.7%) patients died. Crude 3-year mortality of patients in New York Heart Association (NYHA) classes I, II, and III/IV was 9.5%, 16.5%, and 49.7%, respectively (P<0.001). Stepwise Cox regression analysis showed that the combination of 7 factors was the best model to predict the mortality of AS patients, who were scored according to their hazard ratios, including NYHA class III-IV (score 6), male sex (3), serum albumin level ≤4 g/dl (2), aortic peak flow ≥4.5 m/s (2), age ≥75 years (2), chronic kidney disease (2), and anemia (1). Receiver-operating characteristic analysis showed excellent association between the sum of the scores and 3-year mortality (area under the curve, 0.78). The multivariate Cox proportional hazard model demonstrated that the present risk score also well stratified the mortality risk.

CONCLUSIONS

The present study demonstrates that, in addition to the classical prognostic factors related to symptoms and AS severity, various comorbidities are associated with mortality. Thus, the present comprehensive risk score may be useful for risk stratification of AS patients.

Can biomarkers help to diagnose early heart failure with preserved ejection fraction?

Early heart failure with preserved ejection fraction (HFpEF) is a frequent disease, but its diagnosis is difficult and relies mostly on the evidence of left ventricular filling pressure (LVFP) elevation during exercise. Several reports have suggested that natriuretic peptides plasma levels reflect exercise-induced increase in LVFP, but they still have significant limitations. In this context, any new laboratory biomarker that can accurately reflect LVFP elevation during exercise is desirable. Recently, cardiotrophin-1, soluble endoglin, ST2, growth differentiation factor 15, galectin-3, and other new laboratory markers associated with LVFP have emerged. However, the current data on the relationship of these biomarkers and diastolic dysfunction are limited to resting conditions. Therefore, their secretion deserves to be tested under the exercise to determine their potential role in making a diagnosis of early HFpEF.

N-terminal pro-B-type natriuretic peptide measurement is useful in predicting left ventricular hypertrophy regression after aortic valve replacement in patients with severe aortic stenosis

BACKGROUND

The predictive factors for early left ventricular hypertrophy (LVH) regression after aortic valve replacement (AVR) have not been fully elucidated. This study was conducted to investigate which preoperative parameters predict early LVH regression after AVR.

METHODS AND RESULTS

87 consecutive patients who underwent AVR due to isolated severe aortic stenosis (AS) were analysed. Patients with ejection fraction <50% or concomitant coronary artery disease were excluded from the analysis. Preoperative evaluation including echocardiography and N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurement was performed and midterm follow-up echocardiography was done at a median of 9 months after AVR. The presence of complete regression of LVH at the midterm follow-up was determined. In multivariate analysis, including preoperative echocardiographic parameters, only E/e' ratio was associated with midterm LVH regression (OR 1.11, 95% CI 1.01 to 1.22; p=0.035). When preoperative NT-proBNP was added to the analysis, logNT-proBNP was found to be the single significant predictor of midterm LVH regression (OR 2.00, 95% CI 1.08 to 3.71; p=0.028). By receiver operating characteristic curve analysis, a cut-off value of 440 pg/mL for NT-proBNP yielded a sensitivity of 72% and a specificity of 77% for the prediction of LVH regression after AVR.

CONCLUSIONS

Preoperative NT-proBNP was an independent predictor for early LVH regression after AVR in patients with isolated severe AS.

Tumor marker carbohydrate antigen 125 predicts adverse outcome after transcatheter aortic valve implantation

OBJECTIVES

This study sought to predict the value of tumor marker carbohydrate antigen 125 (CA125) before and after transcatheter aortic valve implantation (TAVI) for all-cause death and a composite endpoint of death, admission for heart failure, myocardial infarction, and stroke (major adverse cardiac events [MACE]).

BACKGROUND

Risk stratification after TAVI remains challenging. The use of biomarkers in this setting represents an unmet need.

METHODS

CA125 was measured in 228 patients before and after TAVI. The association with outcomes was assessed using parametric Cox regression and joint modeling for baseline and longitudinal analyses, respectively. CA125 was evaluated as logarithm transformation and dichotomized by its median value (M1 ≤15.7 U/ml vs. M2 >15.7 U/ml).

RESULTS

At a median follow-up of 183 days (interquartile range: 63 to 365) and 144 days (interquartile range: 56 to 365), 50 patients (22%) died and 75 patients (33%) experienced MACE. A 3-fold increase in the rates for death and MACE was observed in patients above the median (M2 vs. M1) of CA125 (5.2 vs. 1.6 per 10 person-years and 8.3 vs. 3.3 per 10 person-years, respectively; p for both <0.001). In a multivariable analysis adjusted for logistic EuroSCORE, New York Heart Association functional class III/IV, and device success, baseline values of CA125 (M2 vs. M1) independently predicted death (hazard ratio [HR]: 2.18; 95% confidence interval [CI]: 1.11 to 4.26; p = 0.023) and MACE (HR: 1.77; 95% CI: 1.05 to 2.98; p = 0.031). In the longitudinal analysis, lnCA125 as a time-varying exposure, was highly associated with both endpoints: HR: 1.47; 95% CI: 1.01 to 2.14; p = 0.043 and HR: 2.26; 95% CI: 1.28 to 3.98; p = 0.005, for death and MACE, respectively.

CONCLUSIONS

Serum levels of CA125 before and after TAVI independently predict death and MACE.

B-type natriuretic peptide in the recognition of critical congenital heart disease in the newborn infant

OBJECTIVE

Infants with congenital heart disease having obstruction to the left ventricular outflow and ductal-dependent systemic circulation can present critically ill with shock. Prompt disease recognition and initiation of prostaglandins are necessary to prevent excess morbidity and mortality. We assessed a large cohort of newborn infants with ductal-dependent systemic circulation to determine if B-type natriuretic peptide (BNP) is consistently elevated at presentation, potentially aiding in diagnosis and treatment.

METHODS

The clinical records of infants with left-sided obstructive lesions admitted from January 2005 to June 2009 were reviewed. Infants were divided into 2 groups: group 1 was diagnosed with cardiogenic/circulatory shock at presentation, and group 2 consisted of infants with ductal-dependent systemic circulation without evidence of shock. B-type natriuretic peptide levels and other variables between the groups were compared.

RESULTS

All patients with critical congenital heart disease presenting with shock had elevated BNP levels, ranging from 553 to greater than 5000 pg/mL. Infants in group 1 (shock, n = 36) had significantly higher median BNP levels of 4100 pg/mL at presentation compared with group 2 patients (no shock, n = 86), who had a median BNP of 656 pg/mL (range, 30-3930 pg/mL; P < 0.001). Every 100 U of increase in BNP at presentation increased the likelihood of shock (odds ratio, 100; P < 0.001).

CONCLUSIONS

B-type natriuretic peptide is markedly elevated in neonates presenting in shock secondary to left-sided obstructive heart disease and is an important diagnostic tool to aid in the rapid identification and treatment of these patients.

Association of somatic and cognitive depressive symptoms and biomarkers in acute myocardial infarction: insights from the translational research investigating underlying disparities in acute myocardial infarction patients' health status registry

BACKGROUND

Somatic depressive symptoms and certain biomarkers are each associated with worse acute myocardial infarction (AMI) prognosis, but the relationship between depressive symptom domains and inflammatory, neurohormonal, and coagulation markers is unknown.

METHODS

We examined the relationship between depressive symptoms and 1-month biomarker levels (high-sensitivity C-reactive protein [hs-CRP], N-terminal pro-brain natriuretic peptide [NT-proBNP], white blood cell [WBC], platelet counts) in 1265 AMI patients. Depressive symptoms (9-item Patient Health Questionnaire) were assessed during index hospitalization and categorized as somatic or cognitive. Using median regression models, the upper quartile of somatic and cognitive depression scores and each biomarker were compared with the lower three quartiles, adjusting for site, demographics, and clinical characteristics.

RESULTS

Although hs-CRP values were higher in patients with somatic symptoms, this association was attenuated after adjustment (B(per SD increase) = .02, 95% confidence interval: .00; .05, p = .07). WBC count was independently associated with somatic depressive symptoms (B(per SD increase) = .28, 95% confidence interval: .12; .44, p < .001). Cognitive depressive symptoms were not associated with hs-CRP or WBC count. Neither dimension was associated with NT-proBNP or platelet levels. For each biomarker, the depression dimensions explained <1% of their variation.

CONCLUSIONS

Neither somatic nor cognitive depressive symptoms were meaningfully associated with hs-CRP, NT-proBNP, WBC, or platelet counts 1 month after AMI, suggesting that the association between depression and long-term outcomes may be unrelated to these biomarkers. Future research should explore other biomarkers to better illuminate pathways by which depression adversely impacts AMI prognosis.

Usefulness of serial brain natriuretic peptide measurements for managing aortic valve stenosis in pregnancy

Among developed countries, valvular aortic stenosis (AS) in pregnant women is primarily due to a congenitally bicuspid aortic valve, which occurs in approximately 1% of the general adult population. Most asymptomatic patients and those with mild to moderate AS can be managed conservatively to full-term pregnancy. However, those with more severe AS with symptoms require more aggressive treatment. The medical management of severe symptomatic AS is not ideal; hence, these women are typically treated with percutaneous balloon valvuloplasty or surgical aortic valve replacement. However, both interventions are associated with inherent risks. In addition, symptoms such as dyspnea and decreased exercise tolerance are commonly exhibited in normal pregnant women, making it difficult to distinguish symptoms associated with normal pregnancy from those caused by AS. We report the first case of congenitally bicuspid severe AS in pregnancy that was successfully managed medically to full term by following consecutive brain natriuretic peptide levels.

NT-proBNP, NT-proANP and cTnI concentrations in dogs with pre-capillary pulmonary hypertension

OBJECTIVES

To compare [NT-proBNP], [NT-proANP] and [cTnI] between control dogs with respiratory disease without pulmonary hypertension (PH) and dogs with pre-capillary PH, and to assess the accuracy of [NT-proBNP], [NT-proANP], [cTnI] to predict Doppler-derived peak tricuspid regurgitation (TR) gradient.

ANIMALS

20 dogs. 8 control dogs with respiratory disease with no PH and 12 with pre-capillary PH.

METHODS

[NT-proBNP], [NT-proANP] and [cTnI] were compared between the 2 groups and simple linear regression analysis was used to predict peak TR gradients from various blood biomarkers.

RESULTS

Median [NT-proBNP] was higher in the dogs with PH (2011 pmol/L, 274-7713 pmol/L) compared to control dogs (744 pmol/L; 531-2710 pmol/L) (p = 0.0339). [NT-proBNP] was associated with peak TR gradient (R(2) = 0.7851, p = 0.0001). Median [NT-proANP] did not differ between dogs with PH (1747 fmol/L; 894-2884 fmol/L) and control dogs (1209 fmol/L; 976-1389 fmol/L (p = 0.058). [NT-proANP] was not associated with peak TR gradient (R(2) = 0.2780, p = 0.0781). Median [cTnI] did not differ between dogs with PH (0.2850 ng/mL; 0.19-1.13 ng/mL) and control dogs (0.2 ng/mL; 0.19-0.82 ng/mL, p = 0.3051). Median [TnI] was not associated with peak TR gradient (R(2) = 0.024, p = 0.6307).

CONCLUSIONS

[NT-proBNP] concentration is significantly higher in dogs with pre-capillary PH when compared to dogs with respiratory disease without PH, and [NT-proBNP] may be useful to predict the severity of estimated PH. Elevations in [NT-proBNP] due to pre-capillary PH may complicate the interpretation of [NT-proBNP] elevations in patients presenting with cardiorespiratory abnormalities. [NT-proANP] and [cTnI] were not elevated in dogs with pre-capillary PH.

Molecular mechanisms underlying cardiac antihypertrophic and antifibrotic effects of natriuretic peptides

Natriuretic peptides (NPs) exert well-characterized protective effects on the cardiovascular system, such as vasorelaxation, natri- and diuresis, increase of endothelial permeability, and inhibition of renin-angiotensin-aldosterone system. It has been reported that they also possess antihypertrophic and antifibrotic properties and contribute actively to cardiac remodeling. As a consequence, they are involved in several aspects of cardiovascular diseases. Antihypertrophic and antifibrotic actions of NPs appear to be mediated by specific signaling pathways within a more complex cellular network. Elucidation of the molecular mechanisms underlying the effects of NPs on cardiac remodeling represents an important research objective in order to gain more insights on the complex network leading to cardiac hypertrophy, ventricular dysfunction, and transition to heart failure, and in the attempt to develop novel therapeutic agents. The aim of the present article is to review well-characterized molecular mechanisms underlying the antihypertrophic and antifibrotic effects of NPs in the heart that appear to be mainly mediated by guanylyl cyclase type A receptor. In particular, we discuss the calcineurin/NFAT, the sodium exchanger NHE-1, and the TGFβ1/Smad signaling pathways. The role of guanylyl cyclase type B receptor, along with the emerging functional significance of natriuretic peptide receptor type C as mediators of CNP antihypertrophic and antifibrotic actions in the heart are also considered.

Early hemodynamic and neurohormonal response after transcatheter aortic valve implantation

BACKGROUND

The conventional surgical aortic bioprostheses used for treatment of aortic stenosis (AS) are inherently stenotic in nature. The more favorable mechanical profile of the Medtronic CoreValve bioprosthesis may translate into a better hemodynamic and neurohormonal response.

PATIENTS AND METHODS

The early hemodynamic and neurohormonal responses of 56 patients who underwent successful transcatheter aortic valve implantation (TAVI) using the Medtronic CoreValve bioprosthesis for severe symptomatic AS were compared with those of 36 patients who underwent surgical aortic valve replacement (SAVR) using tissue valves in the same period.

RESULTS

At baseline, patients in the TAVI and SAVR group had comparable indexed aortic valve area (0.33 ± 0.1 vs 0.34 ± 0.1 cm² , respectively; P = .69) and mean transvalvular gradient (51.1 ± 16.5 vs 53.1 ± 14.3 mm Hg, respectively; P = .56). At 30-day follow-up, mean transvalvular gradient was lower in the TAVI group than in the SAVR group (10.3 ± 4 vs 13.1 ± 6.2 mm Hg, respectively; P = .015), and the indexed aortic valve area was larger in the TAVI group (1.0 ± 0.14 vs 0.93 ± 0.13 cm²/m²; P = .017). There was a trend toward a higher incidence of moderate patient-prosthesis mismatch in the surgical group compared with the TAVI group (30.5% vs 17.8%, respectively; P = .11). The overall incidence of prosthetic regurgitation (any degree) was higher in the TAVI group than in the SAVR group (85.7% vs 16.7%, respectively; P < .00001). The left ventricular mass index decreased after TAVI (175.1 ± 61.8 vs 165.6 ± 57.2 g/m²; P = .0003) and remained unchanged after SAVR (165.1 ± 50.6 vs 161 ± 64.8 g/m²; P = .81). Similarly, NT-ProBNP decreased after TAVI (3,479 ± 2,716 vs 2,533 ± 1,849 pg/mL; P = .033) and remained unchanged after SAVR (1,836 ± 2,779 vs 1,689 ± 1,533 pg/mL; P = .78). There was a modest correlation between natriuretic peptides and left ventricular mass index in the whole cohort (r = 0.4, P = .013).

CONCLUSION

In patients with severe AS, TAVI resulted in lower transvalvular gradients and higher valve areas than SAVR. Such hemodynamic performance after TAVI may have contributed to early initiation of a reverse cardiac remodeling process and a decrease in natriuretic peptides.

[Role of natriuretic peptides in the assessment of aortic stenosis severity]

BACKGROUND/AIM

Symptom onset is a critical point in natural course of aortic stenosis and the most important indication for aortic valve replacement. The aim of the study was to evaluate the role of natriuretic peptides level in the assessment of symtomatic status of patients with severe aortic stenosis and the preserved left ventricular systolic function.

METHODS

In 67 patients with isolated severe aortic stenosis symptomatic status, transthoracic echocardiography, and BNP and NT-proBNP plasma level were assesed. Natriuretic peptides levels were also measured in 36 healthy controls.

RESULTS

BNP and NT-proBNP levels were significantly higher in the patients with aortic stenosis compared with the healthy controls. The symptomatic patients had a higher level of natriuretic peptides than the asymptomatic ones (BNP 118 [29-266] vs. 79 [44-90] pg/mL, p < 0.001; NT-proBNP 258 [67-520], vs. 79 [77-112] pmol/L, p < 0.0001). Natriuretic peptides levels increased with the severity of NYHA class. NT-proBNP level higher than 122 pmol/L was a cutoff value for detection of symptoms in the patients with severe aortic stenosis.

CONCLUSION

The levels of natriuretic peptides were significantly higher in the patients with symptomatic aortic stenosis, and increased with NYHA class. Measurement of natriuretic peptides levels could be important addition to clinical and echocardiographic assesment in determing optimal timing for valve replacement in aortic stenosis.

Natriuretic peptides and right atrial fibrosis in patients with paroxysmal versus persistent atrial fibrillation

Natriuretic peptides (NPs) are excellent diagnostic and prognostic markers of heart failure, but their roles in atrial fibrillation (AF), particularly of isolated cardiac valvular origin, are unclear. We assessed the mRNA and protein content of pro-atrial natriuretic peptide (pro-ANP) and pro-brain natriuretic peptide (pro-BNP) in right atrial appendages (RAAs) and their N-terminal fragments (nt-proANP and nt-proBNP) in the plasma of 30 patients with paroxysmal AF (PaAF) and 40 patients with persistent AF (PeAF) matched with 34 patients in sinus rhythm (SR) undergoing isolated valvular replacement. To explore the underlying mechanism, fibrosis related examinations were simultaneously carried out in RAAs. Unexpectedly, atrial expression of pro-NPs mRNA was notably augmented in the PaAF subgroup, but not so pronounced in the PeAF subgroup. Atrial content of pro-NPs proteins and plasma nt-proNPs, between which surprisingly strong positive correlations were found (pro-ANP and nt-proANP: r=0.918, p<0.001; pro-BNP and nt-proBNP: r=0.913, p<0.001), were increased analogously in PaAF and PeAF subgroups. We identified significantly increasing gradients of atrial collagen volume fraction (CVF), levels of collagen I and III in the SR, PaAF and PeAF groups, and convincing negative linear correlations between CVF, levels of collagen I and III, and atrial transcripts of pro-NPs. These findings suggest that the discordance between transcripts and protein contents of pro-NPs was possibly due to the more outstanding atrial fibrosis in PeAF, and that circulating nt-proNPs levels could reflect the corresponding atrial pro-NPs contents in this report.

Relationship between N-terminal pro-B-type natriuretic peptide (Nt-proBNP) and cardiac cycle efficiency in cardiac surgery

N-terminal pro-B-type natriuretic peptide (Nt-proBNP) is a peptide released from myocardium in response to ventricular wall stress and dysfunction. Nt-proBNP plasma levels are elevated in a variety of cardiovascular disorders and are largely used for diagnosis and treatment of cardiac diseases. The cardiac cycle efficiency (CCE) is a haemodynamic variable that represents the left ventricle wall stress and the heart's effort to maintain an adequate blood flow to tissues. We investigated the relationship between Nt-proBNP and CCE values in patients undergoing cardiac surgery. Twenty-five patients undergoing aortic valve replacement were studied. Plasma Nt-proBNP concentrations were performed by electroluminescence immunoassay before starting surgery (t0), at the end of extracorporeal circulation (t1) and 3 hours after surgery (t2). CCE measurements were acquired at the same intervals and correlations with Nt-proBNP levels were calculated. Nt-proBNP plasma concentration was 1430 ± 341 pg/ml at t0, peaked significantly at t1 (2129 ± 561 pg/ml, p<0.001) and moderately decreased at t2 (1924 ± 477 pg/ml, p<0.05). A direct correlation between Nt-proBNP measured at t0 and t1 was found (r=0.91, p<0.001). Overall, a negative correlation between CCE and proBNP values was found (r=-0.89, p<0.01). Correlations between CCE and Nt-proBNP were -0.91, -0.83 and -0.88, at t0, t1 and t2, respectively (p<0.01). Nt-proBNP levels reflect the severity of left ventricle dysfunction in patients undergoing cardiac surgery. CCE correlated well with serum Nt-proBNP levels and seems to be a useful variable to monitor the left ventricular stress and recovery during the various phases of surgery.

Left ventricular torsional dynamics in aortic stenosis: relationship between left ventricular untwisting and filling pressures. A two-dimensional speckle tracking study

AIMS

The contribution of left ventricular (LV) untwisting to LV suction and early-diastolic filling was previously demonstrated, but this was not yet tested in patients with aortic stenosis (AS). We sought to assess the relationship between LV untwisting and LV filling pressures in patients with severe AS and normal left ventricular ejection fraction (LVEF) using speckle tracking echocardiography.

METHODS AND RESULTS

Sixty-one consecutive patients (66 +/- 9 years) with severe AS, preserved LVEF (63 +/- 6%), and 40 normal subjects (47 +/- 12 years) were prospectively enrolled. A comprehensive echocardiographic examination was performed in all. LV rotation and twisting were assessed using speckle tracking echocardiography. Peak apical back rotation rate, peak LV untwisting rate, and time intervals from QRS onset (ECG) to each of them were measured. Brain natriuretic peptide (BNP) levels were determined in 30 patients. Patients with AS were older than normal subjects (P < 0.001). LV mass, LA volume, LV filling pressures as well as peak apical back rotation rate and time to peak apical back rotation rate were increased in patients (P < 0.05 for all). In patients with AS, both time to peak LV untwisting rate and time to peak apical back rotation rate were significantly related to E/E' ratio and to BNP levels (P < 0.04 for all).

CONCLUSION

In patients with severe AS and preserved LVEF, there is a significant relationship between LV untwisting and LV filling pressures, suggesting a role for impaired LV untwisting in the pathophysiology of diastolic dysfunction in this setting.

New cardiovascular biomarkers: clinical implications in patients with valvular heart disease

Valvular heart disease (VHD) is characterized by an ongoing, inflammatory cellular response which results in a left ventricular hemodynamic stress change in response to valvulopathy. The current inflammatory hypothesis suggests that as the heart valve disease progresses the inflammatory cytokine response is activated causing continuation of deleterious effects on the heart and vasculature. This can lead to progression of heart failure and left ventricular dysfunction. Over the last 10 years, a number of biologically active molecules, termed biomarkers, have been discovered in VHD. These can be used to detect the progression and pathogenesis of heart failure and to assess the severity of inflammation (e.g., C-reactive protein). Brain natriuretic peptide (BNP) can diagnose underlying cardiac systolic and diastolic dysfunction. In high-risk patients BNP is also considered to be a useful tool for assisting in the diagnosis and monitoring the progression of VHD. Patients with symptomatic VHD benefit from aortic valve surgery; however, management in the absence of symptoms remains challenging. While the lack of symptoms can delay aortic valve replacement, unselected premature aortic valve replacement may be associated with unbalanced risks of cardiac surgery. This review summarizes the current and emerging clinical and potential research application of specific biomarkers of VHD.

Comparison of brain natriuretic peptide plasma levels versus logistic EuroSCORE in predicting in-hospital and late postoperative mortality in patients undergoing aortic valve replacement for symptomatic aortic stenosis

The accuracy of the logistic EuroSCORE (logES), a widely used risk prediction algorithm for cardiac surgery including aortic valve surgery, usually overestimates observed perioperative mortality. Elevated brain natriuretic peptide (BNP) in symptomatic patients with aortic stenosis (AS) is associated with a poor short-term outcome after aortic valve replacement. We aimed to compare BNP with the logES for predicting short- and long-term outcome in symptomatic patients with severe AS undergoing aortic valve replacement. We prospectively studied 144 consecutive patients referred for aortic valve replacement (42% women, 73 +/- 9 years, mean aortic gradient 51 +/- 18 mm Hg, and left ventricular ejection fraction 61 +/- 11%) undergoing either isolated aortic valve replacement (58%) or combined to bypass grafting. Both plasma BNP and logES was estimated before surgery. The median BNP plasma level and logES were 157 pg/ml (interquartile range [IQR] 61 to 440) and 6.6% (IQR 4.2 to 12.2), respectively. The perioperative mortality was 6% and the overall mortality by the end of the study was 13%. Patients with logES >10.1% (upper tertile) had a higher risk of dying over time (hazard ratio [HR] 2.86, p = 0.037), as had patients with BNP >312 pg/ml (HR 9.01, p <0.001). Discrimination (based on C statistic) and model performance (based on Akaike information criterion) were better for BNP than for logES. At the bivariable analysis, only BNP was an independent predictor of death (HR 8.2, p = 0.002). Preoperative BNP was even more accurate than logES in predicting outcome. In conclusion, in symptomatic patients with severe AS, high preoperative BNP plasma level and high logES confirm their predicting value for short- and long-term outcome.

Heart failure in patients with aortic stenosis: Clinical and prognostic significance of carbohydrate antigen 125 and brain natriuretic peptide measurement

BACKGROUND

Brain natriuretic peptide (BNP) is related to symptomatic status and outcome in aortic stenosis (AS) patients. Carbohydrate antigen 125 (CA125) demonstrated recently a BNP-like behaviour in patients with congestive heart failure (CHF) but has never been studied in AS patients. We aimed to assess the role of CA125 and BNP in AS patients.

METHODS

CA125 and BNP blood levels, transthoracic echocardiography and independent evaluation of CHF symptoms were obtained in 64 consecutive patients (76+/-9 years; 35 males) with AS (valve area 0.9+/-0.3 cm(2)). A pre-specified combined end-point consisting of cardiac mortality, urgent aortic valve replacement and hospitalization for CHF was considered. The median follow-up was 8 months (interquartile range 4.5-10 months).

RESULTS

Both CA125 and BNP have accurately identified patients with III-IV NYHA class: area under the ROC curve was 0.85 for CA125 and 0.78 for BNP (best cut-offs of 10.3 U/mL and 254.64 pg/mL respectively) and were independently correlated to left ventricular ejection fraction. Fifty-two percent of patients with CA125>or=10.3 U/mL vs. 13% with CA125<10.3 U/mL (p<0.01) and 65% patients with BNP>or=254 pg/mL vs. 7% with BNP<254 pg/mL (p<0.001) have reached the end-point.

CONCLUSIONS

Both CA125 and BNP levels are significantly correlated with NYHA class and outcome in patients with AS. CA125 blood level assessment (less expensive) may improve the clinical management in this setting.

Serum markers of systemic right ventricular function and exercise performance

The right ventricle, which faces systemic pressure due to congenital heart disease, often develops premature systolic dysfunction. Cardiac hormones might be useful to identify patients with such systolic dysfunction. This prospective study investigated the relationship of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels with right ventricular ejection fraction (RVEF) and exercise performance in patients with a systemic right ventricle. ANP levels were obtained in 24 patients and BNP levels were obtained in 22 patients with systemic right ventricle. Patients underwent exercise study (n = 22) and cardiovascular magnetic resonance imaging (n = 11) or equilibrium radionuclide angiography (n = 13) to determine RVEF. There were 17 patients with complete transposition and 7 patients with corrected transposition. ANP showed an inverse correlation with RVEF (r2 = 0.63, p < 0.001), a weak but statistically significant inverse correlation with exercise duration (r2 = 0.18, p = 0.047) and no relationship with maximal oxygen consumption (peak V'O2) (r2 = 0.10, p = NS). BNP did not show a relationship with any of the parameters measured. ANP shows a strong inverse correlation with RVEF and a weak correlation with exercise duration in patients with a systemic right ventricle. BNP does not show a significant relationship when compared with either parameter. ANP might be a useful tool for identification of systolic right ventricular dysfunction.

Natriuretic peptides in cardiovascular diseases

The natriuretic peptide family comprises atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), dendroaspis natriuretic peptide (DNP), and urodilatin. The activities of natriuretic peptides and endothelins are strictly associated with each other. ANP and BNP inhibit endothelin-1 (ET-1) production. ET-1 stimulates natriuretic peptide synthesis. All natriuretic peptides are synthesized from polypeptide precursors. Changes in natriuretic peptides and endothelin release were observed in many cardiovascular diseases: e.g. chronic heart failure, left ventricular dysfunction and coronary artery disease.