Design and methods of the Pro-B Type Natriuretic Peptide Outpatient Tailored Chronic Heart Failure Therapy (PROTECT) Study

Heart failure with recovered ejection fraction: Current understanding and future prospects

Heart failure with reduced ejection fraction (HFrEF) is a prevalent kind of heart failure in which a significant amount of the ejection fraction can be repaired, and left ventricular remodeling and dysfunction can be reversed or even restored completely. However, a considerable number of patients still present clinical signs and biochemical features of incomplete recovery from the pathophysiology of heart failure and are at risk for adverse outcomes such as re-deterioration of systolic function and recurrence of HFrEF. Furthermore, it is revealed from a microscopic perspective that even if partial or complete reverse remodeling occurs, the morphological changes of cardiomyocytes, extracellular matrix deposition, and abnormal transcription and expression of pathological genes still exist. Patients with "recovered ejection fraction" have milder clinical symptoms and better outcomes than those with continued reduction of ejection fraction. Based on the unique characteristics of this subgroup and the existence of many unknowns, the academic community defines it as a new category-heart failure with recovered ejection fraction (HFrecEF). Because there is a shortage of natural history data for this population as well as high-quality clinical and basic research data, it is difficult to accurately evaluate clinical risk and manage this population. This review will present the current understanding of HFrecEF from the limited literature.

Cardiac Remodeling in Hypertension: Clinical Impact on Brain, Heart, and Kidney Function

Hypertension is the most common causative factor of cardiac remodeling, which, in turn, has been associated with changes in brain and kidney function. Currently, the role of blood biomarkers as indices of cardiac remodeling remains unclear. In contrast, cardiac imaging, including echocardiography and cardiovascular magnetic resonance (CMR), has been a valuable noninvasive tool to assess cardiac remodeling. Cardiac remodeling during the course of systemic hypertension is not the sole effect of the latter. "Remodeling" of other vital organs, such as brain and kidney, also takes place. Therefore, it will be more accurate if we discuss about "hypertensive remodeling" involving the heart, the brain, and the kidneys, rather than isolated cardiac remodeling. This supports the idea of their simultaneous assessment to identify the early, silent lesions of total "hypertensive remodeling". In this context, magnetic resonance imaging is the ideal modality to provide useful information about these organs in a noninvasive fashion and without radiation. For this purpose, we propose a combined protocol to employ MRI in the simultaneous assessment of the heart, brain and kidneys. This protocol should include all necessary indices for the evaluation of "hypertensive remodeling" in these 3 organs, and could be performed within a reasonable time, not exceeding one hour, so that it remains patient-friendly. Furthermore, a combined protocol may offer "all in one examination" and save time. Finally, the amount of contrast agent used will be limited granted that post-contrast evaluations of the three organs will be performed after 1 injection.

A Systematic Review of Tafamidis in Patients With Transthyretin Amyloid Cardiomyopathy

Transthyretin amyloid cardiomyopathy disease burden is increasing daily due to advancements in diagnostic and imaging modalities in the modern world. Tafamidis is one of many therapeutic options. The main objective of this review is to study the role of Tafamidis in slowing the progression of transthyretin cardiomyopathy (TTR-CM) by analyzing randomized controlled trials (RCTs) and non-RCTs of Tafamidis. We searched for published papers of Tafamidis in the English language in electronic databases like Google Scholar, PubMed, Cochrane Library, and PubMed Central. We imported the resulting articles from our search to Mendeley software. Four reviewers removed the duplicates and performed title and abstract screening of the articles. The same reviewers obtained the full-text of relevant articles and did full-text screening based on eligibility criteria. Finally, five reviewers performed a quality assessment of RCTs using the Cochrane risk of bias assessment and of non-RCTs by a checklist prepared by Downs and Black. Any disagreements about any process were resolved by a discussion with other authors. One RCT and five non-RCTs of Tafamidis were included in this systematic review. From the non-RCTs, stability was observed in different parameters like echocardiographic findings, cardiac biomarkers, and ECG in patients with transthyretin cardiomyopathy during the study duration with Tafamidis. ATTR-ACT (Tafamidis in Transthyretin Cardiomyopathy Clinical Trial) trial demonstrated reduction of cardiovascular events and all-cause mortality in the Tafamidis group in comparison to placebo. In both RCT and non-RCTs, Tafamidis was established as a safe and tolerable drug for patients with TTR-CM. Our study proved the role of Tafamidis in reducing cardiovascular events, all-cause mortality, and the progression of cardiac disease in TTR-CM patients. In addition to five non-RCTs, current evidence is based on the findings of only one RCT of Tafamidis. Hence, evidence from additional RCTs is required to strongly support the stability of parameters like echocardiographic findings, cardiac biomarkers, and ECG with Tafamidis use.

AST/ALT ratio predicts the functional severity of chronic heart failure with reduced left ventricular ejection fraction

Objective

Despite previous research that focused on liver transaminases as predictors of cardiovascular disease, there has been limited research evaluating the predictive value of AST/ALT ratio in patients with heart failure. We aimed to investigate AST/ALT ratio as an indicator of the functional severity in chronic heart failure with reduced left ventricular ejection fraction.

Results

Overall, 105 patients previously diagnosed with HFrEF from Buraidah-Al Qassim province, Saudi Arabia were included in this retrospective cross-sectional study. Data on study variables, including demographic data, left ventricular ejection fraction, NYHA class, and AST/ALT ratio, were collected from patients’ records. The patients were divided into two groups, namely group-1 (AST/ALT ratio < 1) and group-2 (AST/ALT ratio ≥ 1), to identify any differences in their cardiac function profiles. NYHA class and NT-proBNP were higher and LVEF was lower in group-2 than in group-1. We found a mild significant correlation between AST/ALT ratio and APRI, FIB-4 score, NYHA-class, and LVEF (r = 0.2, 0.25, 0.26, and − 0.24, respectively; P < 0.05). Multivariate linear regression analysis model and ROC curve showed that AST/ALT ratio could independently predict HFrEF functional severity with a best cut-off value of 0.9, sensitivity of 43.6%, and specificity of 81.4%.

Early NT-proBNP and MR-proANP associated with QoL 1 year after acutely decompensated heart failure: secondary analysis from the MOLITOR trial

Aim: Heart failure negatively impacts quality of life (QoL), which in turn contributes to an adverse long-term prognosis. We aimed at identifying biomarker trajectories after an episode of acutely decompensated heart failure (ADHF) that differ between patients showing average versus impaired QoL 1 year later, thus allowing to predict impaired QoL. Methods: Biomarkers were repeatedly measured throughout the year in 104 ADHF patients. QoL was assessed at discharge and 1 year after ADHF. Logistic regression and receiver operating characteristic analyses were used to identify predictors of impaired QoL while controlling psychosocial confounders. Results: MR-proANP predicted impaired physical and mental QoL. NT-proBNP measurements were important predictors for poor physical QoL. Conclusion: MR-proANP and NT-proBNP predict poor QoL after an epidode of ADHF. The trial is registered at http://clinicaltrials.gov as MOLITOR (IMpact of therapy optimisation On the Level of biomarkers in paTients with Acute and Decompensated ChrOnic HeaRt Failure) with unique identifier: NCT01501981.

Imaging, Biomarker, and Clinical Predictors of Cardiac Remodeling in Heart Failure With Reduced Ejection Fraction

In response to injury, hemodynamic changes, or neurohormonal activation, the heart undergoes a series of structural and functional changes that have been termed cardiac remodeling. Remodeling is defined as changes in cardiac geometry and/or function over time and can be measured in terms of changes in cardiac chamber dimensions, wall thickness, volumes, mass, and ejection fraction at serial imaging examinations. As to cardiac chambers, left ventricular (LV) remodeling has been best studied in patients with heart failure with reduced ejection fraction. Although LV remodeling may compensate for abnormal hemodynamic parameters and function in the short term, left unchecked, it is associated with worsening cardiac function and poor prognosis. On the other hand, reversing LV geometry and/or function closer to that of a normal heart (also known as reverse remodeling) is associated with improved cardiac function and better prognosis. Because of its close relationship with clinical outcomes, remodeling may potentially be targeted in clinical management and used in trials as a surrogate endpoint. Standardized definition of remodeling and reliable tools to predict and monitor the presence, direction, and magnitude of cardiac remodeling are needed. Together with clinical and imaging findings, circulating biomarkers (most notably N-terminal pro-B-type natriuretic peptide, high-sensitivity troponin, and soluble suppression of tumorigenesis-2) may be helpful in this respect.

MicroRNAs Associated With Reverse Left Ventricular Remodeling in Humans Identify Pathways of Heart Failure Progression

BACKGROUND

Plasma extracellular RNAs have recently garnered interest as biomarkers in heart failure (HF). Most studies in HF focus on single extracellular RNAs related to phenotypes and outcomes, and few describe their functional roles. We hypothesized that clusters of plasma microRNAs (miRNAs) associated with left ventricular (LV) remodeling in human HF would identify novel subsets of genes involved in HF in animal models.

METHODS AND RESULTS

We prospectively measured circulating miRNAs in 64 patients with systolic HF (mean age, 64.8 years; 91% men; median LV ejection fraction, 26%) with serial echocardiography (10 months apart) during medical therapy. We defined LV reverse remodeling as a 15% reduction in LV end-systolic volume index. Using principal components analysis, we identified a component associated with LV reverse remodeling (odds ratio=3.99; P=0.01) that provided risk discrimination for LV reverse remodeling superior to a clinical model (C statistic, 0.58 for a clinical model versus 0.71 for RNA-based model). Using network bioinformatics, we uncovered genes not previously widely described in HF regulated simultaneously by >2 miRNAs. We observed increased myocardial expression of these miRNAs during HF development in animals, with downregulation of target gene expression, suggesting coordinate miRNA-mRNA regulation. Target mRNAs were involved in autophagy, metabolism, and inflammation.

CONCLUSIONS

Plasma miRNAs associated with LV reverse remodeling in humans are dysregulated in animal HF and target clusters of genes involved in mechanisms implicated in HF. A translational approach integrating human HF, bioinformatics, and model systems may uncover novel pathways involved in HF.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00351390.

A review on B-type natriuretic peptide monitoring: assays and biosensors

Since its discovery in 1988, B-type natriuretic peptide (BNP) has been recognized as a powerful cardiovascular biomarker for a number of disease states, specifically heart failure. Concurrent with such a discovery, much effort has been allocated to the precise monitoring of physiological BNP levels. Thus, it can be used to guide the therapy of heart failure and determine the patient's stage of disease. Thus, we discuss in this article BNP as a potent biomarker. Subsequently, we will review the progress of biosensing devices as they could be applied to monitor BNP levels as assays, benchtop biosensors and implantable biosensors. The analytical characteristics of commercially available BNP assays are presented. Still emerging as a field, we define four obstacles that present opportunity for the future development of implantable biosensor: foreign body response, sensor renewability, sensitivity and selectivity.

Serial Heart Rates, Guideline-Directed Beta Blocker Use, and Outcomes in Patients With Chronic Heart Failure With Reduced Ejection Fraction

A single heart rate (HR) measurement may inform future prognosis in chronic heart failure with reduced ejection fraction (HFrEF). The importance of elevated HR across serial assessment is uncertain, particularly with well-applied guideline-directed medical therapy (GDMT) with beta blockers (BBs). In this post hoc analysis of 129 patients with chronic HFrEF in sinus rhythm, who had aggressive medication titration over 10.6 months, HR and BB use were assessed at each visit (average of 6 visits per patient). All-cause mortality was assessed. At baseline, 81 subjects (62.8%) had HR ≥70 beats/min; 40 subjects (31.0%) had high HR despite being on ≥50% of GDMT BB dose. At final visit, 30.4% of the subjects still had high HR despite achieving ≥50% target BB dose. There were no significant baseline differences in demographics or BB doses in patients with HR <70 vs HR ≥70 beats/min. In adjusted model in which HR was treated as time-dependent covariate, an increase in HR of 10  beats/min was associated with an increased hazard of all-cause mortality during follow-up (adjusted hazard ratio per 10 beats/min = 2.46; 95% confidence interval 1.46-4.16, p <0.001). In conclusion, in well-managed patients with HFrEF, high HR was frequent even after aggressive medication titration, and often despite being on at least 50% of GDMT BB dose. An increase in HR was associated with worse clinical outcomes (Clinicaltrials.gov NCT#00351390).

Systematic Evaluation of Endothelin 1 Measurement Relative to Traditional and Modern Biomarkers for Clinical Assessment and Prognosis in Patients With Chronic Systolic Heart Failure: Serial Measurement and Multimarker Testing

OBJECTIVES

To define the role of single or serial measurement of endothelin 1 (ET-1) for prognostication beyond traditional and modern markers of risk in heart failure (HF).

METHODS

In total, 115 patients with chronic systolic HF were followed for 10 months. Clinical assessment and ET-1, N-terminal pro-B-type natriuretic peptide (NT-proBNP), highly sensitive troponin I (hsTnI), soluble ST2 (sST2), and galectin 3 were measured at each visit.

RESULTS

Elevated ET-1 was associated with worse HF, lower right ventricular function, higher pulmonary pressure, and higher left atrial volume index despite similar left ventricular function. ET-1 correlated with angiotensin-converting enzyme inhibitor use. A model containing traditional risk factors, ET-1, NT-proBNP, hsTnI, and sST2 best predicted cardiovascular events, and ET-1 improved reclassification. In an adjusted time-integrated model, percent time spent with ET-1 of 5.90 pg/mL or less was predictive of fewer cardiovascular events (odds ratio, 0.75; 95% confidence interval, 0.62-0.91). ET-1 reduction over time was associated with a lower rate of cardiovascular events compared with increasing or stable ET-1 (24.4% vs 50.0%).

CONCLUSIONS

ET-1 may be a unique predictor of HF prognosis, complementing other biomarkers in a multimarker profile. Serial measurement of ET-1 may provide additional prognostic information.

B-type natriuretic peptide-guided treatment for heart failure

BACKGROUND

Heart failure is a condition in which the heart does not pump enough blood to meet all the needs of the body. Symptoms of heart failure include breathlessness, fatigue and fluid retention. Outcomes for patients with heart failure are highly variable; however on average, these patients have a poor prognosis. Prognosis can be improved with early diagnosis and appropriate use of medical treatment, use of devices and transplantation. Patients with heart failure are high users of healthcare resources, not only due to drug and device treatments, but due to high costs of hospitalisation care. B-type natriuretic peptide levels are already used as biomarkers for diagnosis and prognosis of heart failure, but could offer to clinicians a possible tool to guide drug treatment. This could optimise drug management in heart failure patients whilst allaying concerns over potential side effects due to drug intolerance.

OBJECTIVES

To assess whether treatment guided by serial BNP or NT-proBNP (collectively referred to as NP) monitoring improves outcomes compared with treatment guided by clinical assessment alone.

SEARCH METHODS

Searches were conducted up to 15 March 2016 in the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library; MEDLINE (OVID), Embase (OVID), the Database of Abstracts of Reviews of Effects (DARE) and the NHS Economic Evaluation Database in the Cochrane Library. Searches were also conducted in the Science Citation Index Expanded, the Conference Proceedings Citation Index on Web of Science (Thomson Reuters), World Health Organization International Clinical Trials Registry and ClinicalTrials.gov. We applied no date or language restrictions.

SELECTION CRITERIA

We included randomised controlled trials of NP-guided treatment of heart failure versus treatment guided by clinical assessment alone with no restriction on follow-up. Adults treated for heart failure, in both in-hospital and out-of-hospital settings, and trials reporting a clinical outcome were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, extracted data and evaluated risk of bias. Risk ratios (RR) were calculated for dichotomous data, and pooled mean differences (MD) (with 95% confidence intervals (CI)) were calculated for continuous data. We contacted trial authors to obtain missing data. Using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, we assessed the quality of the evidence and GRADE profiler (GRADEPRO) was used to import data from Review Manager to create a 'Summary of findings' table.

MAIN RESULTS

We included 18 randomised controlled trials with 3660 participants (range of mean age: 57 to 80 years) comparing NP-guided treatment with clinical assessment alone. The evidence for all-cause mortality using NP-guided treatment showed uncertainty (RR 0.87, 95% CI 0.76 to 1.01; patients = 3169; studies = 15; low quality of the evidence), and for heart failure mortality (RR 0.84, 95% CI 0.54 to 1.30; patients = 853; studies = 6; low quality of evidence).The evidence suggested heart failure admission was reduced by NP-guided treatment (38% versus 26%, RR 0.70, 95% CI 0.61 to 0.80; patients = 1928; studies = 10; low quality of evidence), but the evidence showed uncertainty for all-cause admission (57% versus 53%, RR 0.93, 95% CI 0.84 to 1.03; patients = 1142; studies = 6; low quality of evidence).Six studies reported on adverse events, however the results could not be pooled (patients = 1144; low quality of evidence). Only four studies provided cost of treatment results, three of these studies reported a lower cost for NP-guided treatment, whilst one reported a higher cost (results were not pooled; patients = 931, low quality of evidence). The evidence showed uncertainty for quality of life data (MD -0.03, 95% CI -1.18 to 1.13; patients = 1812; studies = 8; very low quality of evidence).We completed a 'Risk of bias' assessment for all studies. The impact of risk of bias from lack of blinding of outcome assessment and high attrition levels was examined by restricting analyses to only low 'Risk of bias' studies.

AUTHORS' CONCLUSIONS

In patients with heart failure low-quality evidence showed a reduction in heart failure admission with NP-guided treatment while low-quality evidence showed uncertainty in the effect of NP-guided treatment for all-cause mortality, heart failure mortality, and all-cause admission. Uncertainty in the effect was further shown by very low-quality evidence for patient's quality of life. The evidence for adverse events and cost of treatment was low quality and we were unable to pool results.

Established and Emerging Roles of Biomarkers in Heart Failure Clinical Trials

The role of circulating biomarkers in heart failure clinical trials has evolved in recent decades. Increasing evidence behind the use of natriuretic peptides, emergence of novel biomarkers, and increased emphasis on targeting therapies toward physiological basis of disease (so-called precision medicine) have all contributed to the continued expansion of biomarker use in heart failure clinical trials. We will explore the advantages and pitfalls encountered through the use of biomarkers in clinical trials as an inclusion criterion, toxicity marker, and end point. We will also review their role in providing insights into the mechanism of action of therapeutics and guiding therapy in the management of patients with heart failure.

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.

Cardiac findings and events observed in an open-label clinical trial of tafamidis in patients with non-Val30Met and non-Val122Ile hereditary transthyretin amyloidosis

A phase 2, open-label study in 21 patients with non-Val30Met and non-Val122Ile hereditary transthyretin amyloidosis showed that tafamidis (20 mg daily for 12 months) stabilized these transthyretin variants. We assessed cardiac amyloid infiltration and cardiac abnormalities in this same study population. At baseline, median age was 64.3 years, 11 patients were in NYHA class II, 13 had conduction abnormalities, 14 N-terminal pro-hormone brain natriuretic peptide concentrations >300 pg/ml, and 17 interventricular septal thickness >12 mm. Mean (SD) left ventricular ejection fraction was 60.3 % (9.96). Patients with normal heart rate variability increased from 4/19 at baseline to 8/19 at month 12 (p < 0.05). Cardiac biomarkers remained stable. Although four patients had increases in interventricular septal thickness ≥2 mm, the remainder had stable septal wall thickness. There were no clinically relevant changes in mean echocardiographic/electrocardiographic variables and no safety concerns.

Galectin-3 and mineralocorticoid receptor antagonist use in patients with chronic heart failure due to left ventricular systolic dysfunction

BACKGROUND

Galectin-3 is a prognostic heart failure biomarker associated with aldosterone-induced myocardial fibrosis; mineralocorticoid receptor antagonists (MRAs) may reduce such fibrosis. We sought to examine outcomes of patients with heart failure with reduced ejection fraction (HFrEF) as a function of galectin-3 and MRA therapy.

METHODS

A total of 151 patients with chronic HFrEF were categorized by baseline galectin-3 and subsequent MRA therapy trends with regard to cardiovascular (CV) events, left ventricular remodeling, safety, and quality of life, over a mean of 10 months.

RESULTS

Although galectin-3 >20 ng/mL was associated with doubling in adjusted risk for CV events, regardless of MRA treatment, there was no difference in CV event rates with regard to MRA use patterns, independent of galectin-3 concentrations. Specifically, in patients with elevated galectin-3 treated with intensified MRA therapy, a significant difference was not detected in CV event rates (P = .79) or the cumulative number of such events (P = .76). Adjusted analysis revealed no difference in time to first CV event if MRA was added/intensified in those with elevated galectin-3 (hazard ratio 0.99, 95% CI 0.97-1.02, P = .74); similarly, cumulative MRA dose was not a specific predictor of benefit. In those with elevated galectin-3, MRA therapy did not affect left ventricular remodeling indices or quality of life at follow-up; these patients had the highest rates of treatment-related adverse events with intensified MRA use. Regardless of MRA use, elevated galectin-3 was associated with more significant renal dysfunction.

CONCLUSIONS

Among patients with chronic HFrEF and elevated galectin-3 concentrations, we found no specific benefit from addition or intensification of MRA therapy.

Prognostic usefulness of insulin-like growth factor-binding protein 7 in heart failure with reduced ejection fraction: a novel biomarker of myocardial diastolic function?

Insulin-like growth factor-binding protein 7 (IGFBP7) is a biomarker that has recently been associated with heart failure and cardiac hypertrophy. The aim of this study was to examine IGFBP7 relative to echocardiographic abnormalities reflecting diastolic dysfunction. One hundred twenty-four patients with ambulatory heart failure with reduced ejection fraction and baseline detailed 2-dimensional echocardiograms were followed for a mean of 10 months. IGFBP7 was measured serially at each office visit; 108 patients underwent follow-up echocardiography. Echocardiographic parameters of diastolic function were compared at baseline and over time. IGFBP7 concentrations were not linked to left ventricular size or systolic function. In contrast, those with elevated baseline IGFBP7 concentrations were more likely to have abnormalities of parameters describing diastolic function, such as higher left atrial volume index, transmitral E/A ratio, E/E' ratio, and right ventricular systolic pressure. IGFBP7 was correlated with left atrial volume index (ρ = 0.237, p = 0.008), transmitral E/A ratio (ρ = 0.304, p = 0.001), E/E' ratio (ρ = 0.257, p = 0.005), and right ventricular systolic pressure (ρ = 0.316, p = 0.001). Furthermore, each was found to be independently predictive of IGFBP7 in adjusted analysis. In subjects with baseline and final echocardiograms, more time spent with elevated IGFBP7 concentrations in serial measurement was associated with worsening diastolic function and increasing left atrial volume index or right ventricular systolic pressure. IGFBP7 concentrations were predictive of an increased risk for cardiovascular events independent of echocardiographic measures of diastolic function (p = 0.006). In conclusion, IGFBP7 is a novel prognostic biomarker for heart failure with reduced ejection fraction and shows significant links to the presence and severity of echocardiographic parameters of abnormal diastolic function.

Soluble Concentrations of the Interleukin Receptor Family Member ST2 and β-Blocker Therapy in Chronic Heart Failure

Background—

Concentrations of soluble (s)ST2 predict prognosis in heart failure. We recently found changing doses of β-blocker (BB) may affect sST2 concentrations. It remains unclear whether sST2 concentrations identify benefit of BB therapy, however.

Methods and Results—

A total of 151 subjects with heart failure attributable to left ventricular systolic dysfunction were examined in this post hoc analysis; >96% were taking BB at enrollment. Medication regimen and sST2 values were obtained during 10 months. Cardiovascular events were examined as a function of baseline sST2 status (low ≤35 versus high >35 ng/mL) and final achieved BB dose (high ≥50 versus low <50 mg daily equivalent dose of metoprolol succinate). Patients with low sST2 titrated to high-dose BB had the lowest cardiovascular event rate at 0.53 events ( P =0.001), and lowest cumulative hazard ( P =0.003). Those with low sST2/low-dose BB, or high sST2/high-dose BB had intermediate outcomes (0.92 and 1.19 events). Patients with high sST2 treated with low-dose BB had the highest cardiovascular event rate (2.08 events) and the highest cumulative hazard. Compared with low sST2/high-dose BB, those with high sST2 treated with low-dose BB had an odds ratio of 6.77 ( P <0.001) for a cardiovascular event. Patients with low sST2/low-dose BB or high sST2/high-dose BB had intermediate odds ratios for cardiovascular events ( P =0.18 and 0.02). Similar results were found for heart failure hospitalization and cardiovascular death.

Conclusions—

Although BB therapy exerted dose-related benefits across all study participants, sST2 measurement identifies patients with chronic heart failure who may particularly benefit from higher BB doses.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00351390.

Increased perioperative b-type natriuretic peptide associates with heart failure hospitalization or heart failure death after coronary artery bypass graft surgery

BACKGROUND

Heart failure (HF) is a leading cause of hospitalization and mortality. Plasma B-type natriuretic peptide (BNP) is an established diagnostic and prognostic ambulatory HF biomarker. We hypothesized that increased perioperative BNP independently associates with HF hospitalization or HF death up to 5 yr after coronary artery bypass graft surgery.

METHODS

The authors conducted a two-institution, prospective, observational study of 1,025 subjects (mean age = 64 ± 10 yr SD) undergoing isolated primary coronary artery bypass graft surgery with cardiopulmonary bypass. Plasma BNP was measured preoperatively and on postoperative days 1-5. The study outcome was hospitalization or death from HF, with HF events confirmed by reviewing hospital and death records. Cox proportional hazards analyses were performed with multivariable adjustments for clinical risk factors. Preoperative and peak postoperative BNP were added to the multivariable clinical model in order to assess additional predictive benefit.

RESULTS

One hundred five subjects experienced an HF event (median time to first event = 1.1 yr). Median follow-up for subjects who did not have an HF event = 4.2 yr. When individually added to the multivariable clinical model, higher preoperative and peak postoperative BNP concentrations each, independently associated with the HF outcome (log10 preoperative BNP hazard ratio = 1.93; 95% CI, 1.30-2.88; P = 0.001; log10 peak postoperative BNP hazard ratio = 3.38; 95% CI, 1.45-7.65; P = 0.003).

CONCLUSIONS

Increased perioperative BNP concentrations independently associate with HF hospitalization or HF death during the 5 yr after primary coronary artery bypass graft surgery. Clinical trials may be warranted to assess whether medical management focused on reducing preoperative and longitudinal postoperative BNP concentrations associates with decreased HF after coronary artery bypass graft surgery.

Serial measurement of galectin-3 in patients with chronic heart failure: results from the ProBNP Outpatient Tailored Chronic Heart Failure Therapy (PROTECT) study

AIMS

Galectin-3 is a prognostic heart failure (HF) biomarker that may mediate cardiac fibrosis. We examined the value of serial galectin-3 measurement for prognosis and response to therapy in chronic HF.

METHODS AND RESULTS

A total of 151 subjects with LV systolic dysfunction (LVSD) were followed through 908 visits over 10 ± 3 months. The amount of time spent with a galectin-3 level ≤ 20.0 ng/mL and changes between baseline and subsequent values were considered across visits, and used to assess risk for adverse cardiovascular (CV) events and associations with LV remodelling. Medication effects on galectin-3 were examined. Median galectin-3 values at baseline, 3 months, and 6 months were higher in patients with CV events (21.7 vs. 18.4 ng/mL, P = 0.03; 21.7 vs. 16.5 ng/mL, P = 0.03; 23.2 vs. 16.0 ng/mL, P = 0.007). Galectin-3 concentration changed in 35.2% of subjects during study procedures; time spent at ≤ 20.0 ng/mL was significantly associated with a lower rate of CV events, independently predicted fewer CV events even adjusted for relevant variables including study allocation, NT-proBNP, and renal function [odds ratio (OR) = 0.90; P = 0.05], and predicted increase in LV ejection fraction (OR = 1.20; P = 0.04). Serial galectin-3 measurement at 6 months added prognostic value beyond the baseline level (P = 0.02). There were no significant effects of medications on galectin-3 levels.

CONCLUSION

In chronic HF due to LVSD, serial galectin-3 measurement adds incremental prognostic information and predicts LV remodelling. In this study, HF therapies had no clear effects on galectin-3 levels.

Improvement in structural and functional echocardiographic parameters during chronic heart failure therapy guided by natriuretic peptides: mechanistic insights from the ProBNP Outpatient Tailored Chronic Heart Failure (PROTECT) study

AIMS

We sought to determine if heart failure (HF) care with a goal to lower N-terminal pro B-type natriuretic peptide (NT-proBNP) concentrations, compared with standard of care (SOC) management, is associated with improvement in echocardiographic parameters of cardiac structure and function.

METHODS AND RESULTS

Of 151 subjects with HF due to left ventricular systolic dysfunction (LVSD) prospectively randomized to NT-proBNP-guided vs. SOC HF care, 116 had serial echocardiographic data. Endpoints in this echocardiographic study included the relationship between change in NT-proBNP and LV reverse remodelling, as well as associations between biomarker-guided therapy and measures of diastolic function, right ventricular (RV) size and function, estimates of LV filling pressure and RV systolic pressure (RVSP), and the degree of mitral regurgitation (MR). After a mean of 10 months of study procedures, in adjusted analyses, final NT-proBNP concentrations predicted risk of remodelling [hazard ratio (HR) ↑LV end-diastolic volume index = 1.43, 95% confidence interval (CI) 1.10-1.86, P = 0.007; HR ↑LV end-systolic volume index = 1.54, 95% CI 1.10-1.91, P = 0.01; HR ↓LV ejection fraction (LVEF) = 1.53, 905% CI 1.12-1.89, P = 0.02]. In addition to greater improvement in LVEF and reductions in LV volume, compared with SOC, NT-proBNP-guided patients showed significant decreases in the ratio of early transmitral peak velocity to early diastolic peak annular velocity (E/E'), pulmonary vein peak S velocity, RV fractional area change, RVSP, and MR severity.

CONCLUSION

NT-proBNP concentrations may serve as a non-invasive indicator of the state of cardiac structure and function in HF due to LVSD. Multiple, prognostically meaningful echocardiographic variables improved more significantly in patients treated with NT-proBNP-guided care vs. SOC.

Quality of life and chronic heart failure therapy guided by natriuretic peptides: results from the ProBNP Outpatient Tailored Chronic Heart Failure Therapy (PROTECT) study

BACKGROUND

Heart failure (HF) treatment guided by amino-terminal pro-B type natriuretic peptide (NT-proBNP) may reduce cardiovascular event rates compared to standard-of-care (SOC) management. Comprehensive understanding regarding effect of NT-proBNP guided care on patient-reported quality of life (QOL) remains unknown.

METHODS

One hundred fifty-one subjects with HF due to left ventricular systolic dysfunction were randomized to either SOC HF management or care with a goal to reduce NT-proBNP values ≤1000 pg/mL. Effects of HF on QOL were assessed using the Minnesota Living with HF Questionnaire (MLHFQ) quarterly, with change (Δ) in score assessed across study procedures and as a function of outcome.

RESULTS

Overall, baseline MLHFQ score was 30. Across study visits, QOL improved in both arms, but was more improved and sustained in the NT-proBNP arm (repeated measures P = .01); NT-proBNP patients showing greater reduction in MLHFQ score (-10.0 vs -5.0; P = .05), particularly in the physical scale of the questionnaire. Baseline MLHFQ scores did not correlate with NT-proBNP; in contrast, ∆MLHFQ scores modestly correlated with ∆NT-proBNP values (ρ = .234; P = .006) as did relative ∆ in MLHFQ score and NT-proBNP (ρ = .253; P = .003). Considered in tertiles, less improvement in MLHFQ scores was associated with a higher rate of HF hospitalization, worsening HF, and cardiovascular death (P = .001).

CONCLUSIONS

We describe novel associations between NT-proBNP concentrations and QOL scores among patients treated with biomarker guided care. Compared to SOC HF management, NT-proBNP guided care was associated with greater and more sustained improvement in QOL (Clinical Trial Registration: www.clinicaltrials.govNCT00351390).

The appropriate use of biomarkers in heart failure

Natriuretic peptides and troponins have been extensively studied and used in heart failure, and their value has been extensively discussed. Renal markers, such as cystasin-C, NGAL, and KIM-1, have shown growing utility in heart failure. The activation of compensatory pathways and ongoing hemodynamic changes result in the release of biomarkers that can be monitored to chart disease progression and possibly target for therapy.

Novel biomarkers in chronic heart failure

Understanding of chronic heart failure (HF) has progressed from a syndrome of disordered hemodynamics caused by alterations in the structure of the heart to one that involves intertwined molecular pathways in disarray. Accordingly, the assessment and treatment of patients with chronic HF has shifted from a focus on hemodynamics to modification of maladaptive molecular processes. Accumulating evidence shows that molecular biomarkers of disease could provide a unique window into the pathophysiology of chronic HF, potentially improving our ability to predict adverse outcomes, provide novel drug targets, and even help gauge therapeutic efficacy. The more 'traditional' biomarkers such as cardiac troponin, natriuretic peptides, and C-reactive protein have been studied in large cohorts of patients with chronic HF and have relatively established clinical applications. In this Review, we summarize the properties, clinical data, and potential applications of some emerging biomarkers that could uniquely indicate the level of biomechanical stretch, inflammation, ventricular remodeling, myocardial injury, and renal dysfunction that occurs in chronic HF. We will also discuss the potential role for these biomarkers within a multimarker-based strategy that could, in the future, lead to better care for these patients.

Biomarkers in cardiovascular clinical trials: past, present, future

BACKGROUND

Cardiovascular (CV) clinical trials are instrumental in understanding treatment effects and offer insights into the natural progression of CV disease. Biomarkers are a critical component of patient selection, end point definition, and safety monitoring, and clinical trials provide a platform for the discovery and validation of new biomarkers that may augment the understanding of disease mechanisms, risk stratification, and/or clinical decision-making.

CONTENT

We review the roles that biomarkers have played in CV clinical trials and roles that CV clinical trials have played and will continue to play in the discovery and validation of biomarkers and their implementation in clinical practice. Large biobanks containing multiple specimen types are increasingly being created from patients enrolled in clinical trials, and such biobanks, when coupled with advances in molecular techniques and bioinformatics, promise to accelerate our understanding of CV disease mechanisms and to help fuel the discovery and development of novel therapeutic targets and biomarkers of risk and treatment response.

SUMMARY

The past, present, and future of biomarkers and clinical trials have been and will remain intertwined. Biomarkers were once the workhorses of patient selection and end point definition in clinical trials; more recently, clinical trials have been the proving ground for individual biomarkers. Attention to biobanking and the application of modern informatics and molecular techniques to samples collected within clinical trials will usher in the era of stratified and personalized medicine.

Updating the role of natriuretic peptide levels in cardiovascular disease

Heart disease affects 1 in 3 individuals in the United States, and the prevalence of heart failure (HF) is increasing exponentially. Although our understanding of the disease progression of congestive HF (CHF) has advanced, refining the areas of diagnosis, risk stratification, prognosis, and treatment is still needed. The natriuretic peptides, specifically B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), have shown promise in clinical practice. Brain natriuretic peptide is released from cardiac ventricular myocytes in response to volume or pressure overload. Rapid measurement of plasma BNP or NT-proBNP has been shown to increase the diagnostic accuracy of HF exacerbations. A cutoff value of 100 pg/mL has a sensitivity and specificity of 90% and 73%, respectively, according to the Breathing Not Properly Study. In addition, BNP and NT-proBNP have been considered independent predictors of adverse outcome. One study calculated a 35% increase in risk of death due to HF for every 100-pg/mL increase in BNP level. Lastly, natriuretic peptides have been known to decrease following medical therapy of HF, suggesting the role of their measurement in monitoring inpatient disease progression and outpatient medical programs. The future of natriuretic peptides lies in risk stratification in other cardiac diseases, such as acute coronary syndrome, and possibly determining severity of valvular disease. Although there is substantial work done in elucidating the power of natriuretic peptides in clinical practice, more research is necessary to reach a consensus regarding how to appropriately utilize them in treatment regimens.

The role of natriuretic peptide testing in guiding chronic heart failure management: review of available data and recommendations for use

The care of patients with heart failure can be challenging, with few objective tools available to assist in therapy decision-making. Natriuretic peptides are powerfully prognostic biomarkers in patients with heart failure and may represent an objective target for therapy. Accordingly, the use of biomarker-guided care with either B-type natriuretic peptide (BNP) or amino-terminal pro-B-type natriuretic peptide (NT-proBNP) has been recently explored. Over the past few years, a number of studies with heterogeneous inclusion criteria, methods and results have been performed. We have reviewed the available literature, summarizing the results of biomarker-guided heart failure trials and deriving recommendations for optimal application of biomarker-guided heart failure care based on the experience gained. In general, positive studies had low BNP or NT-proBNP target concentrations (∼100 pg/mL and ∼1000 pg/mL, respectively) and achieved lower natriuretic peptide concentrations compared with standard care. Patients in the biomarker-guided arms of the studies typically received more aggressive heart failure care and had no excess adverse outcomes. In the recent ProBNP Outpatient Tailored Chronic Heart Failure Therapy (PROTECT) study, patients treated with biomarker-guided care also had improved quality of life and significantly better reverse remodeling on echocardiography compared with patients who received standard care. In conclusion, heart failure therapy guided by a goal to reduce natriuretic peptide concentrations below prognostically-meaningful levels results in more aggressive heart failure care, is well tolerated and is associated with superior outcomes.

Use of amino-terminal pro-B-type natriuretic peptide to guide outpatient therapy of patients with chronic left ventricular systolic dysfunction

OBJECTIVES

The aim of this study was to evaluate whether chronic heart failure (HF) therapy guided by concentrations of amino-terminal pro-B-type natriuretic peptide (NT-proBNP) is superior to standard of care (SOC) management.

BACKGROUND

It is unclear whether standard HF treatment plus a goal of reducing NT-proBNP concentrations improves outcomes compared with standard management alone.

METHODS

In a prospective single-center trial, 151 subjects with HF due to left ventricular (LV) systolic dysfunction were randomized to receive either standard HF care plus a goal to reduce NT-proBNP concentrations ≤1,000 pg/ml or SOC management. The primary endpoint was total cardiovascular events between groups compared using generalized estimating equations. Secondary endpoints included effects of NT-proBNP-guided care on patient quality of life as well as cardiac structure and function, assessed with echocardiography.

RESULTS

Through a mean follow-up period of 10 ± 3 months, a significant reduction in the primary endpoint of total cardiovascular events was seen in the NT-proBNP arm compared with SOC (58 events vs. 100 events, p = 0.009; logistic odds for events 0.44, p = 0.02); Kaplan-Meier curves demonstrated significant differences in time to first event, favoring NT-proBNP-guided care (p = 0.03). No age interaction was found, with elderly patients benefitting similarly from NT-proBNP-guided care as younger subjects. Compared with SOC, NT-proBNP-guided patients had greater improvements in quality of life, demonstrated greater relative improvements in LV ejection fraction, and had more significant improvements in both LV end-systolic and -diastolic volume indexes.

CONCLUSIONS

In patients with HF due to LV systolic dysfunction, NT-proBNP-guided therapy was superior to SOC, with reduced event rates, improved quality of life, and favorable effects on cardiac remodeling. (Use of NT-proBNP Testing to Guide Heart Failure Therapy in the Outpatient Setting; NCT00351390).

Use of natriuretic peptides to guide and monitor heart failure therapy

BACKGROUND

Plasma B-type cardiac natriuretic peptides reflect cardiac structure and function and have proven roles in assisting in the diagnosis of acute heart failure. They are independent prognostic indicators across the full spectrum of cardiovascular disease. Serial changes in plasma B-type cardiac natriuretic peptides parallel prognosis in chronic heart failure. Beneficial responses to medications and devices used in the treatment of heart failure are associated with decreases in plasma B-type peptide concentrations. This effect has led to the hypothesis that intensified treatment directed at reducing B-peptide concentrations may improve outcomes in heart failure.

CONTENT

The efficacy of serial measurements of plasma B-type peptides in guiding titration of therapy for chronic heart failure has been the subject of several randomized controlled trials reported in the peer-reviewed literature since 2000. These reports are summarized in this review. Trial design, characteristics of the heart-failure population studied, duration of follow-up, exact end points recorded, and target peptide concentrations pursued all differ somewhat between trials. In addition, in studies in which benefits were seen, the exact mechanisms mediating the improvements in outcome were unclear. However, an overall consistency is emerging that is supported by 2 metaanalyses.

SUMMARY

In aggregate the existing trial data suggest that adjustment of treatment in chronic heart failure according to serial B-type peptide measurements, used in conjunction with established clinical methods, is likely to reduce cardiac mortality and hospital admissions with heart failure, at least in patients with systolic heart failure who are younger than 75 years and relatively free of comorbidities.

Tailored therapy for heart failure: neurohormones

Plasma B type cardiac natriuretic peptides reflect cardiac structure and function and have proven roles in assisting in the diagnosis of acute heart failure. They are also powerful independent prognostic indicators across the full spectrum of cardiovascular disease. The efficacy of serial measurements of plasma B type peptides in guiding titration of therapy for chronic heart failure has been the subject of a number of randomized controlled trials. These are summarized in the following brief review. In the decade 2000-2010, 8 trials have been completed. Study design, the characteristics of the heart failure population studied, duration of follow-up, the exact end points recorded, and target peptide levels pursued all differ somewhat between trials. However, an overall consistency is emerging, supported by 2 metaanalyses. In aggregate, the existing trial data suggest that adjustment of treatment in chronic heart failure according to serial B type peptide measurements used in conjunction with established clinical methods is likely to reduce cardiac mortality and admissions with heart failure, at least in those patients aged under 75 years with impaired left ventricular systolic function.

The STARBRITE trial: a randomized, pilot study of B-type natriuretic peptide-guided therapy in patients with advanced heart failure

BACKGROUND

STARBRITE, a multicenter randomized pilot trial, tested whether outpatient diuretic management guided by B-type natriuretic peptide (BNP) and clinical assessment resulted in more days alive and not hospitalized over 90 days compared with clinical assessment alone.

METHODS AND RESULTS

A total of 130 patients from 3 sites with left ventricular ejection fraction ≤35% were enrolled during hospitalization for heart failure (HF) and randomly assigned to therapy guided by BNP and clinical assessment (BNP strategy) or clinical assessment alone. The clinical goal was resolution of congestion without hypotension or renal dysfunction. In the BNP arm, therapy was adjusted to achieve optimal fluid status, defined as the BNP level and congestion score obtained at the time of discharge. In the clinical assessment arm, therapy was titrated to achieve optimal fluid status, represented by the patient's signs and symptoms at the time of discharge. Exclusion criteria were serum creatinine >3.5 mg/dL and acute coronary syndrome. Follow-up was done in HF clinics. BNP was measured with the use of a rapid assay test. There was no significant difference in number of days alive and not hospitalized (hazard ratio 0.72, 95% confidence interval 0.41-1.27; P = .25), change in serum creatinine, or change in systolic blood pressure (SBP). BNP strategy was associated with a trend toward a lower blood urea nitrogen (24 mg/dL vs 29 mg/dL; P = .07); BNP strategy patients received significantly more angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, and the combination of ACE inhibitor or angiotensin receptor blocker plus beta-blockers.

CONCLUSIONS

BNP strategy was not associated with more days alive and not hospitalized, but the strategy appeared to be safe and was associated with increased use of evidence-based medications.

Increased peak postoperative B-type natriuretic peptide predicts decreased longer-term physical function after primary coronary artery bypass graft surgery

BACKGROUND

Increased peak postoperative B-type natriuretic peptide (BNP) is associated with increased major adverse cardiovascular events and all-cause mortality after coronary artery bypass graft (CABG) surgery. Whether increased postoperative BNP predicts worse postdischarge physical function (PF) is unknown. We hypothesized that peak postoperative BNP associates with PF assessed up to 2 yr after CABG surgery, even after adjusting for clinical risk factors. including preoperative PF.

METHODS

This two-institution prospective cohort study included patients undergoing primary CABG surgery with cardiopulmonary bypass. Short Form-36 questionnaires were administered to subjects preoperatively and 6 months, 1 yr, and 2 yr postoperatively. Short Form-36 PF domain scores were calculated using the Short Form-36 norm-based scoring algorithm. Plasma BNP concentrations measured preoperatively and on postoperative days 1-5 were log(10) transformed before analysis. To determine whether peak postoperative BNP independently predicts PF scores 6 months through 2 yr after CABG surgery, multivariable longitudinal regression analysis of the postoperative PF scores was performed, adjusting for important clinical risk factors.

RESULTS

A total of 845 subjects (mean ± SD age, 65 ± 10 yr) were analyzed. Peak postoperative BNP was significantly associated with postoperative PF (effect estimate for log(10) peak BNP, -7.66 PF score points [95% CI, -9.68 to -5.64]; P = <0.0001). After multivariable adjustments, peak postoperative BNP remained independently associated with postoperative PF (effect estimate for log(10) peak BNP, -3.06 PF score points [95% CI, -5.15 to -0.97]; P = 0.004).

CONCLUSIONS

Increased peak postoperative BNP independently associates with worse longer-term PF after primary CABG surgery. Future studies are needed to determine whether medical management targeted toward reducing increased postoperative BNP can improve PF after CABG surgery.