High- versus low-dose ACE inhibition in chronic heart failure: a double-blind, placebo-controlled study of imidapril

Do Heart Failure Biomarkers Influence Heart Failure Treatment Response?

PURPOSE OF REVIEW

Heart failure (HF) is one of the leading causes of cardiac morbidity and mortality around the world. Our evolving understanding of the cellular and molecular pathways of HF has led to the identification and evaluation of a growing number of HF biomarkers. Natriuretic peptides remain the best studied and understood HF biomarkers, with demonstrated clinical utility in the diagnosis and prognostication of HF. Less commonly understood is the utility of HF biomarkers for guiding and monitoring treatment response. In this review, we outline the current HF biomarker landscape and identify novel biomarkers that have potential to influence HF treatment response.

RECENT FINDINGS

An increasing number of biomarkers have been identified through the study of HF mechanisms. While these biomarkers hold promise, they have not yet been proven to be effective in guiding HF therapy. A more developed understanding of HF mechanisms has resulted in an increased number of available pharmacologic HF therapies. In the past, biomarkers have been useful for the diagnosis and prognostication of HF. Future evaluation on their use to guide pharmacologic therapy is ongoing, and there is promise that biomarker-guided therapy will allow clinicians to begin personalizing treatment for their HF patients.

High-dose versus low-dose angiotensin converting enzyme inhibitors in heart failure: systematic review and meta-analysis

OBJECTIVE

To systematically review evidence comparing the effect of low-dose versus high-dose ACE inhibitors (ACEIs) on all-cause and cardiovascular mortality and hospitalisation, functional capacity and side effects in patients with heart failure (HF).

METHODS

We searched PubMed, Embase, Cochrane CENTRAL and LILACS up to January 2019. We included randomised controlled trials (RCTs) comparing low-dose versus high-dose ACEIs in adults with HF with reduced left ventricular ejection fraction (HFrEF). Study selection and data extraction were performed by two independent reviewers. Risk of bias was assessed with RoB 2.0, and quality of evidence with Grading of Recommendations Assessment, Development and Evaluation (GRADE). We conducted random effects meta-analysis and trial sequential analysis.

RESULTS

We included eight RCTs (5829 patients with HF). In comparison with low-dose ACEIs, high-dose ACEIs showed a non-significant effect on all-cause mortality (8 RCTs, n=5828, relative risk (RR) 0.95, 95% CI 0.88 to 1.02; moderate quality of evidence), cardiovascular mortality (6 RCTs, n=4048, RR 0.93, 95% CI 0.85 to 1.01; moderate quality of evidence), all-cause hospitalisation (5 RCTs, n=5394, RR 0.95, 95% CI 0.82 to 1.10; moderate quality of evidence) and cardiovascular hospitalisation (4 RCTs, n=5242, RR 0.98, 95% CI 0.83 to 1.17; low quality of evidence). High-dose ACEI increased functional capacity (4 studies, n=555, standardised mean difference 0.38, 95% CI 0.20 to 0.55; low quality of evidence) and the risk of hypotension (4 RCTs, n=3783, RR 1.64, 95% CI 1.30 to 2.05; moderate quality of evidence). High-dose ACEI had no effect on dizziness (3 RCTs, n=4994, RR 1.37, 95% CI 0.97 to 1.93; low quality of evidence), but decreased the risk of cough (4 RCTs, n=5146, RR 0.85, 95% CI 0.73 to 0.98; moderate quality of evidence).

CONCLUSIONS

The magnitude of benefit of using high dose versus low to intermediate doses of ACEIs might be less than traditionally suggested in clinical guidelines. These findings might help clinicians address the complex task of HF management in a more rational and timely fashion, saving efforts to implement strategies with the greatest net clinical benefit.

Biomarker-Guided Versus Guideline-Based Treatment of Patients With Heart Failure: Results From BIOSTAT-CHF

BACKGROUND

Heart failure guidelines recommend up-titration of angiotensin-converting enzyme (ACE) inhibitor/angiotensin receptor blockers (ARBs), beta-blockers, and mineralocorticoid receptor antagonists (MRAs) to doses used in randomized clinical trials, but these recommended doses are often not reached. Up-titration may, however, not be necessary in all patients.

OBJECTIVES

This study sought to establish the role of blood biomarkers to determine which patients should or should not be up-titrated.

METHODS

Clinical outcomes of 2,516 patients with worsening heart failure from the BIOSTAT-CHF (BIOlogy Study to Tailored Treatment in Chronic Heart Failure) were compared between 3 theoretical treatment scenarios: scenario A, in which all patients are up-titrated to >50% of recommended doses; scenario B, in which patients are up-titrated according to a biomarker-based treatment selection model; and scenario C, in which no patient is up-titrated to >50% of recommended doses. The study conducted multivariable Cox regression using 161 biomarkers and their interaction with treatment, weighted for treatment-indication bias to estimate the expected number of deaths or heart failure hospitalizations at 24 months for all 3 scenarios.

RESULTS

Estimated death or hospitalization rates in 1,802 patients with available (bio)markers were 16%, 16%, and 26%, respectively, in the ACE inhibitor/ARB up-titration scenarios A, B, and C. Similar rates for beta-blocker and MRA up-titration scenarios A, B, and C were 23%, 19%, and 24%, and 12%, 11%, and 24%, respectively. If up-titration was successful in all patients, an estimated 9.8, 1.3, and 12.3 events per 100 treated patients could be prevented at 24 months by ACE inhibitor/ARB, beta-blocker, and MRA therapy, respectively. Similar numbers were 9.9, 4.7, and 13.1 if up-titration treatment decision was based on a biomarker-based treatment selection model.

CONCLUSIONS

Up-titrating patients with heart failure based on biomarker values might have resulted in fewer deaths or hospitalizations compared with a hypothetical scenario in which all patients were successfully up-titrated.

Efficacy of Pharmacologic and Cardiac Implantable Electronic Device Therapies in Patients With Heart Failure and Reduced Ejection Fraction: A Systematic Review and Network Meta-Analysis

Background The treatment of heart failure with reduced ejection fraction has been the subject of numerous randomized controlled trials involving medications and cardiac implantable electronic device therapies. As newer effective pharmacological therapies suggest significant reductions in all-cause mortality, the role of additional device therapy in heart failure with reduced ejection fraction deserves further scrutiny. Methods A systematic review and network meta-analysis on the effect of medication and device therapies in heart failure with reduced ejection fraction on all-cause mortality was performed. Randomized controlled trials published between January 1980 and July 2017 were identified using Medline, EMBASE, and Cochrane Controlled Register of Trials databases. Pcnetmeta package in R was used to calculate treatment arm-based estimated rates, rate ratios, and probability ranks with 95% credible intervals. Results Combination therapy of ACE (angiotensin-converting enzyme) inhibitors or ARBs (angiotensin receptor blockers) with β-blockers (BBs) alone or in addition to implantable cardiac defibrillators or cardiac resynchronization therapy with defibrillators demonstrated a significant reduction of all-cause mortality when compared with placebo. By probability rank, implantable cardiac defibrillator+ACE inhibitor or ARB+BB+mineralocorticoid receptor antagonist, implantable cardiac defibrillator+ACE inhibitor or ARB+BB, and angiotensin receptor-neprilysin inhibitor+BB+mineralocorticoid receptor antagonist combination therapies have the highest probability of being ranked the best treatment. There was no significant difference in the rate of mortality when comparing angiotensin receptor-neprilysin inhibitor+BB+mineralocorticoid receptor antagonist to implantable cardiac defibrillator+optimal pharmacological combination therapy. Conclusions BB and renin-angiotensin system blockers alone or in combination with defibrillator device therapy have robust evidence for a reduction in mortality compared with placebo. The comparative efficacy of pharmacological therapy with angiotensin receptor-neprilysin inhibitors and device therapy deserves further investigation.

Higher versus lower doses of ACE inhibitors, angiotensin-2 receptor blockers and beta-blockers in heart failure with reduced ejection fraction: Systematic review and meta-analysis

Background

Current heart failure (HF) guidelines recommend titrating angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) and beta-blockers (BBs) to target doses used in pivotal placebo-controlled randomized controlled trials (RCTs). Despite a number of RCTs comparing different doses (i.e. higher versus lower doses) of ACEIs, ARBs and BBs, the effects of higher versus lower doses on efficacy and safety remains unclear. For this reason, we performed a systematic review and meta-analysis to evaluate the efficacy and safety of higher versus lower doses of ACEIs, ARBs and BBs in patients with HFrEF.

Methods

We searched MEDLINE, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) via Ovid from inception to April 25^th, 2018 and opentrials.net and clinicaltrials.gov for relevant trials that compared different doses of medications in heart failure. We analyzed trials by drug class (ACEIs, ARBs, and BBs) for efficacy outcomes (all-cause mortality, cardiovascular mortality, all-cause hospitalizations, HF hospitalizations, HF worsening). For safety outcomes, we pooled trials within and across drug classes.

Results

Our meta-analysis consisted of 14 RCTs. Using GRADE criteria, the quality of evidence for ACEIs and ARBs was assessed as generally moderate for efficacy and high for adverse effects, whereas overall quality for BBs was very low to low. Over ~2–4 years higher versus lower doses of ACEIs, ARBs or BBs did not significantly reduce all-cause mortality [ACEIs relative risk (RR) 0.94 (95% confidence interval 0.87–1.02)], ARBs RR 0.96 (0.87–1.04), BBs RR 0.25 (0.06–1.01)] or all cause hospitalizations [ACEIs relative risk (RR) 0.94 (95% confidence interval 0.86–1.02)], ARBs RR 0.98 (0.93–1.04), BBs RR 0.93 (0.39–2.24)]. However, all point estimates favoured higher doses. Higher doses of ARBs significantly reduced hospitalization for HF [RR 0.89 (0.80–0.99)– 2.8% ARR], and higher doses of ACEIs and ARBs significantly reduced HF worsening [RR 0.85 (0.79–0.92)– 5.1% ARR and 0.91 (0.84–0.99)– 3.2% ARR, respectively] compared to lower doses. None of the differences between higher versus lower doses of BBs were significant; however, precision was low. Higher doses of these medications compared to lower doses increased the risk of discontinuation due to adverse events, hypotension, dizziness, and for ACEIs and ARBs, increased hyperkalemia and elevations in serum creatinine. Absolute increase in harms for adverse effects ranged from ~ 3 to 14%.

Conclusions

Higher doses of ACEIs and ARBs reduce the risk of HF worsening compared to lower doses, and higher doses of ARBs also reduce the risk of HF hospitalization but the evidence is sparse and imprecise. Higher doses increase the chance of adverse effects compared to lower doses. Evidence for BBs is inconclusive. These results support initially always starting at low doses of ACEIs/ARBs and only titrating the dose up if the patient tolerates dose increases.

Is the PARADIGM-HF cohort representative of the real-world heart failure patient population?

INTRODUCTION

A new drug with prognostic impact on heart failure, sacubitril/valsartan, has been introduced in current guidelines. However, randomized trial results can be compromised by lack of representativeness. We aimed to assess the representativeness of the PARADIGM-HF trial in a real-world population of patients with heart failure.

METHODS

We reviewed the records of 196 outpatients followed in a heart failure clinic between January 2013 and December 2014. After exclusion of 44 patients with preserved ejection fraction, the inclusion and exclusion criteria of the trial were applied.

RESULTS

Of the 152 patients with systolic heart failure, 106 lacked one or more inclusion criteria and 45 had at least one exclusion criterion. Considering only patients with ejection fraction ≤35% (HFrEF) (n=88), 43 patients lacked at least one inclusion criterion and 25 patients had at least one exclusion criterion. Combining the inclusion and exclusion criteria, 24.3% of patients with systolic HF (ejection fraction ≤50%) and 42% of patients with HFrEF would be eligible for the PARADIGM-HF trial.

CONCLUSION

One in four patients with systolic HF followed in a heart failure outpatient clinic would fulfill the reference study criteria for treatment with the new drug, sacubitril/valsartan.

A prospective study of the impact of AGTR1 A1166C on the effects of candesartan in patients with heart failure

AIM

To evaluate the impact of AGTR1 A1166C (rs5186) on the response to candesartan in patients with heart failure.

MATERIALS & METHODS

Prospective, multicentre, open-label study. We studied 299 symptomatic patients with heart failure presenting a left ventricular ejection fraction ≤40%.

RESULTS

Reductions in the primary end points of natriuretic peptides were not significantly associated with AGTR1 A1166C. Nevertheless, carrying the 1166C allele was associated with a greater compensatory increase in renin activity (p = 0.037) after 16 weeks of treatment with candesartan and a more modest effect on aldosterone concentrations (p = 0.022).

CONCLUSION

AGTR1 1166C carriers may experience a greater long-term compensatory renin-angiotensin-aldosterone system activation following treatment with candesartan. Whether these associations ultimately influence clinical outcomes requires investigation. Clinicaltrials.gov : NCT00400582.

Thirty Years of Evidence on the Efficacy of Drug Treatments for Chronic Heart Failure With Reduced Ejection Fraction: A Network Meta-Analysis

BACKGROUND

Treatments that reduce mortality and morbidity in patients with heart failure with reduced ejection fraction, including angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), β-blockers (BB), mineralocorticoid receptor antagonists (MRA), and angiotensin receptor-neprilysin inhibitors (ARNI), have not been studied in a head-to-head fashion. This network meta-analysis aimed to compare the efficacy of these drugs and their combinations regarding all-cause mortality in patients with heart failure with reduced ejection fraction.

METHODS AND RESULTS

A systematic literature review identified 57 randomized controlled trials published between 1987 and 2015, which were compared in terms of study and patient characteristics, baseline risk, outcome definitions, and the observed treatment effects. Despite differences identified in terms of study duration, New York Heart Association class, ejection fraction, and use of background digoxin, a network meta-analysis was considered feasible and all trials were analyzed simultaneously. The random-effects network meta-analysis suggested that the combination of ACEI+BB+MRA was associated with a 56% reduction in mortality versus placebo (hazard ratio 0.44, 95% credible interval 0.26-0.66); ARNI+BB+MRA was associated with the greatest reduction in all-cause mortality versus placebo (hazard ratio 0.37, 95% credible interval 0.19-0.65). A sensitivity analysis that did not account for background therapy suggested that ARNI monotherapy is more efficacious than ACEI or ARB monotherapy.

CONCLUSIONS

The network meta-analysis showed that treatment with ACEI, ARB, BB, MRA, and ARNI and their combinations were better than the treatment with placebo in reducing all-cause mortality, with the exception of ARB monotherapy and ARB plus ACEI. The combination of ARNI+BB+MRA resulted in the greatest mortality reduction.

Review: Imidapril in Heart Failure

Angiotensin-converting enzyme (ACE) inhibitors improve the prognosis in mild, moderate and severe heart failure, as well as preventing the onset of heart failure in patients with chronic asymptomatic left-ventricular dysfunction and in those with reduced ejection fraction after myocardial infarction (MI). Imidapril is a long-acting ACE inhibitor that is rapidly converted in the liver to its active metabolite, imidaprilat. Maximum plasma concentrations of imidapril and imidaprilat are achieved after 2 and 5—6 hours, respectively, with corresponding elimination half-lives of 1.1—2.5 and 10—19 hours. Imidapril is used in the treatment of hypertension, chronic heart failure, acute MI and diabetic nephropathy. In patients with mild-tomoderate chronic heart failure, imidapril 10 mg once-daily increased exercise time and physical working capacity, decreased plasma atrial natriuretic peptide and brain natriuretic peptide levels and reduced blood pressure. It also improved left ventricular ejection fraction, being significantly more effective than bisoprolol, in patients with acute MI. Imidapril is well tolerated and preliminary studies suggest it has an advantage over captopril and enalapril in terms of a lower incidence of cough. In conclusion, imidapril is a well-investigated versatile ACE inhibitor for the treatment of a range ofACE inhibitor for the treatment of a range of cardiovascular diseases.

Addressing Major Unmet Needs in Patients with Systolic Heart Failure: The Role of Ivabradine

We reviewed clinical evidence for the use of ivabradine in systolic heart failure (HF), in which it appears to improve symptoms, improve quality of life, prevent hospitalization, and prolong survival, thereby addressing unmet needs in the management of HF. Ivabradine provides symptomatic benefits in HF on top of standard therapies, in terms of functional parameters and exercise capacity, and there is some evidence that this leads to improvements in quality of life in symptomatic HF patients, who may have dyspnea, altered exercise capacity, and fatigue. The SHIFT trial demonstrated that ivabradine has significant beneficial effects on major outcomes in HF. Ivabradine had a significant effect on pump failure death, which was reduced by 26 % (p = 0.014), with no effect on sudden cardiac death. This is an important result since pump failure death is currently the main cause of death in HF, and also because the reductions in mortality obtained with beta-blockers and spironolactone in the last 20 years appear to be mainly due to reduction in sudden death rather than reduction in pump failure death. Ivabradine also has a beneficial effect on hospital admissions (-26 %, p < 0.0001), which is clinically relevant since a quarter of HF patients can expect to be readmitted to hospital for HF within 1 month of discharge. Ivabradine-treated patients are also at significantly lower risk of experiencing a second or third hospitalization for worsening HF. Ivabradine clearly has a key role to play in the management of HF by covering the main therapeutic objectives of symptoms, quality of life, and outcomes.

Clinical Characteristics and Treatment of Cardiomyopathies in Children

Cardiomyopathies are diseases of the heart muscle, a term introduced in 1957 to identify a group of myocardial diseases not attributable to coronary artery disease. The definition has since been modified to refer to structural and or functional abnormalities of the myocardium where other known causes of myocardial dysfunction, such as systemic hypertension, valvular disease and ischemic heart disease, have been excluded. In this review, we discuss the pathophysiology, clinical assessment and therapeutic strategies for hypertrophic, dilated and hypertrophic cardiomyopathies, with a particular focus on aspects unique to children.

Fluid Management in Patients with Chronic Heart Failure

Congestion, or fluid overload, is a classic clinical feature of patients presenting with heart failure patients, and its presence is associated with adverse outcome. However, congestion is not always clinically evident, and more objective measures of congestion than simple clinical examination may be helpful. Although diuretics are the mainstay of treatment for congestion, no randomised trials have shown the effects of diuretics on mortality in chronic heart failure patients. Furthermore, appropriate titration of diuretics in this population is unclear. Research is required to determine whether a robust method of detecting - and then treating - subclinical congestion improves outcomes.

Impact of percutaneous coronary intervention on biomarker levels in patients in the subacute phase following myocardial infarction: the Occluded Artery Trial (OAT) biomarker ancillary study

BACKGROUND

The purpose of the Occluded Artery Trial (OAT) Biomarker substudy was to evaluate the impact of infarct related artery (IRA) revascularization on serial levels of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and dynamics of other biomarkers related to left ventricular remodeling, fibrosis and angiogenesis.

METHODS

Patients were eligible for OAT-Biomarker based on the main OAT criteria. Of 70 patients (age 60.8 ± 8.8, 25% women) enrolled in the substudy, 37 were randomized to percutaneous coronary intervention (PCI) and 33 to optimal medical therapy alone. Baseline serum samples were obtained prior to OAT randomization with follow up samples taken at one year. The primary outcome was percent change of NT-proBNP from baseline to 1 year. The secondary outcomes were respective changes of matrix metalloproteinases (MMP) 2 and 9, tissue inhibitor of matrix metalloproteinase 2 (TIMP-2), Vascular Endothelial Growth Factor (VEGF), and Galectin-3.

RESULTS

Paired (baseline and one-year) serum samples were obtained in 62 subjects. Baseline median NT-proBNP level was 944.8 (455.3, 1533) ng/L and decreased by 69% during follow-up (p < 0.0001). Baseline MMP-2 and TIMP-2 levels increased significantly from baseline to follow-up (p = 0.034, and p = 0.027 respectively), while MMP-9 level decreased from baseline (p = 0.038). Levels of VEGF and Galectin-3 remained stable at one year (p = NS for both). No impact of IRA revascularization on any biomarker dynamics were noted.

CONCLUSIONS

There were significant changes in measured biomarkers related to LV remodeling, stress, and fibrosis following MI between 0 and 12 month. Establishing infarct vessel patency utilizing stenting 24 hours-28 days post MI did not however influence the biomarkers' release.

Effect on the atherogenic marker plasminogen activator inhibitor type-1 of addition of the ACE inhibitor imidapril to angiotensin II type 1 receptor antagonist therapy in hypertensive patients with abnormal glucose metabolism: a prospective cohort study in primary care

BACKGROUND AND OBJECTIVE

Renin-angiotensin system (RAS) inhibitors, such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor antagonists (angiotensin receptor blockers [ARBs]), are recommended by the American Diabetes Association for blood pressure control and prevention or management of cardiovascular disease in patients with diabetes mellitus. However, some investigators have suggested that ARBs may increase the risk of myocardial infarction in hypertensive patients. Activation of the RAS is associated with an increased risk of ischaemic events. Angiotensin II stimulates the production of plasminogen activator inhibitor type-1 (PAI-1), a powerful predictor of cardiovascular disease. ACE inhibitors are reported to reduce PAI-1 levels and activity, while ARBs do not reduce or may even elevate levels of this atherogenic marker. The objective of this study was to determine whether the ACE inhibitor imidapril reduces PAI-1 levels in hypertensive patients already being treated with an ARB.

METHODS

This was a prospective cohort study carried out in primary care with a follow-up period of 6 months. Estimating the alpha error (p-value) at 0.05, the power of the test as 80%, and the difference in PAI-1 levels as 10 + or - 15 ng/mL, the required sample size was calculated to be 40. Participants were hypertensive patients taking ARBs for more than 8 weeks, and having dyslipidaemia, obesity or abnormal glucose metabolism. Imidapril 5-10 mg/day was prescribed for 6 months to reduce blood pressure to <130/80 mmHg. The main outcome measure, PAI-1 level, was measured before and 6 months after the addition of imidapril to ARBs in 21 subjects (13 men, eight women), all with abnormal glucose metabolism, nine with dyslipidaemia, and six who were obese. Bodyweight, body mass index, blood pressure, homeostasis model assessment of insulin resistance, glycosylated haemoglobin, creatinine, potassium, high sensitivity C-reactive protein (hs-CRP), and high molecular weight adiponectin levels were measured as secondary outcomes.

RESULTS

PAI-1 level was not significantly changed overall. Hs-CRP level was also not significantly changed; however, the high molecular weight adiponectin level was significantly increased (p = 0.044), especially in men (p = 0.026). There were no significant changes in the other outcomes measured.

CONCLUSION

The current study showed that imidapril added to ARBs did not decrease PAI-1 levels in hypertensive patients with abnormal glucose metabolism; however, this combination therapy significantly increased high molecular weight adiponectin levels in men.

Adverse renal effects of hydrochlorothiazide in rats with myocardial infarction treated with an ACE inhibitor

Diuretics, when added to angiotensin-converting enzyme inhibitors (ACE inhibitors) treatment, can augment the response to ACE inhibitors, but may have adverse effects on renal function, which negatively affect prognosis. While in heart failure rats combined therapy initially improved cardiac function and prognosis, this benefit was completely lost at later stages. We now studied renal effects of adding hydrochlorothiazide to ACE inhibitor after myocardial infarction in rats. Rats were randomized to ACE inhibitor quinapril monotherapy or quinapril with add-on hydrochlorothiazide. Survival was monitored for 14 months. Plasma creatinine, measured at 4 months, was increased by 40% in quinapril with add-on hydrochlorothiazide compared to quinapril. Although overall 14-months mortality was similar in quinapril with add-on hydrochlorothiazide and quinapril, stratification based on plasma creatinine showed increased mortality in the tertile with highest plasma creatinine (P=0.03, Log rank). With add-on hydrochlorotiazide, renal morphology displayed severe renal interstitial lesions; tubular dilatation and fibrosis. Interstitial myofibroblast transformation (alpha-smooth muscle actine staining) was increased at 8 and 14 months, and coincided with collagen deposition and interstitial inflammation (macrophage influx). In rats with quinapril monotherapy or untreated rats, renal structure was normal. Thus, adding hydrochlorotiazide to ACE inhibitor detrimentally affected not only renal function, but also renal structure in rats with myocardial infarction. Altered pharmacokinetics, resulting from a vicious circle of reduced renal function and increased circulating drug levels, may provide an explanation for the adverse renal effects and may exert unfavorable effects on long-term prognosis after myocardial infarction.

Prognostic threshold levels of NT-proBNP testing in primary care

AIMS

Chronic heart failure (HF) is a common condition with a poor prognosis. As delayed diagnosis and treatment of HF patients in primary care can be detrimental, risk-stratified waiting lists for echocardiography might optimize resource utilization. We investigated whether a prognostic threshold level of the cardiac peptide, NT-proBNP, could be identified.

METHODS AND RESULTS

From 2003-2005, 5875 primary care patients with suspected HF (median age 73 years) had NT-proBNP analysed in the Copenhagen area. Eighteen percent died and 20% had a cardiovascular (CV) hospitalization (median follow-up time: 1127 and 1038 days, respectively). In Cox proportional hazards regression models regarding NT-proBNP levels, the fourth decile (range: 83-118 pg/mL) was associated with a 90% (95% CI: 30-190, P < 0.01) increased risk for CV hospitalization and the seventh decile (range: 229-363 pg/mL) was associated with an 80% (95% CI: 20-190, P = 0.01) increased mortality risk after adjustment for age, sex, previous hospitalization, CV diseases, and chronic diseases.

CONCLUSION

We identified prognostic threshold levels for mortality and CV hospitalization for NT-proBNP in primary care patients suspected of HF. Our results have the potential to be used to risk-stratify waiting lists for echocardiography.

Determinants of progression from microalbuminuria to proteinuria in patients who have type 1 diabetes and are treated with angiotensin-converting enzyme inhibitors

The aims of this study were to assess the frequency and determinants of (1) treatment with angiotensin-converting enzyme inhibitors (ACE-I) and (2) progression to proteinuria in the presence of ACE-I treatment in patients with type 1 diabetes and microalbuminuria. A clinic-based cohort study of patients with type 1 diabetes was begun in 1991. The patients who were included in this study (n = 373) are the cohort members who received a diagnosis of microalbuminuria during a 2-yr baseline observation and were followed for 10 yr with frequent assessments of urinary albumin excretion and biennial examinations. Progression to proteinuria occurred when the median urinary albumin excretion during a 2-yr interval exceeded 299 mug/min. During the decade-long study, the proportion of patients who had a history of microalbuminuria and were treated with ACE-I rose from 17 to 67%. Patients who started this treatment had (on average) higher BP, higher urinary albumin excretion, and longer diabetes duration than those who did not. Microalbuminuria often progressed to proteinuria (6.3/100 person-years) in those who were treated. Poor glycemic control and elevated serum cholesterol were the major determinants/predictors of this progression. Although treatment with ACE-I increased during the past decade, it was not completely effective, because microalbuminuria progressed to proteinuria in many treated patients. Poor glycemic control and elevated serum cholesterol were the major determinants/predictors for progression while on ACE-I treatment. The mechanisms that are responsible for the frequent failure of ACE-I to prevent progression of microalbuminuria to proteinuria in a clinical setting are not clear.

What is the Optimal Angiotensin‐Converting Enzyme Inhibitor Dose in Heart Failure?

Doses of angiotensin-converting enzyme (ACE) inhibitors used in the landmark heart failure trials that demonstrated survival benefit are rarely reached in routine practice. The authors review the current literature regarding optimal dosing of ACE inhibitors in heart failure with specific focus on neurohormonal, functional capacity, and clinical outcomes. Neurohormonal studies have shown that lower ACE inhibitor dosing may provide inadequate suppression of the renin-angiotensin-aldosterone system. Higher doses of ACE inhibitors have resulted in greater increments in exercise and functional capacity. Clinically, patients on high-dose ACE inhibitor therapy had significant reductions in all-cause mortality or hospitalization, cardiovascular hospitalizations, and heart failure-specific hospitalizations. There is, however, conflicting evidence, and so continued uncertainty exists regarding optimal dosing. Despite underutilization of ACE inhibitors, there is insufficient evidence to support lower doses. Likewise, limited data exist for doses higher than those used in the landmark trials. Clinicians should therefore attempt to reach target doses in heart failure whenever possible.

Imidapril

Imidapril (Tanatril), through its active metabolite imidaprilat, acts as an ACE inhibitor to suppress the conversion of angiotensin I to angiotensin II and thereby reduce total peripheral resistance and systemic blood pressure (BP). In clinical trials, oral imidapril was an effective antihypertensive agent in the treatment of mild to moderate essential hypertension. Some evidence suggests that imidapril also improves exercise capacity in patients with chronic heart failure (CHF) and reduces urinary albumin excretion rate in patients with type 1 diabetes mellitus. Imidapril was well tolerated, with a lower incidence of dry cough than enalapril or benazepril, and is a first choice ACE inhibitor for the treatment of mild to moderate essential hypertension.

Effects of immunoadsorption on the nt-BNP and nt-ANP plasma levels of patients suffering from dilated cardiomyopathy

Immunoadsorption (IA) represents an additional therapeutic approach in patients with severe heart failure due to dilated cardiomyopathy (DCM). nt-BNP and nt-ANP plasma levels are prognostic markers in patients with heart failure. The effect of IA on nt-BNP and nt-ANP plasma levels is unknown. In this case control study, 30 patients suffering from severe heart failure (LVEF < 35%) due to DCM were included. In 15 patients, IA was carried out in four courses of monthly intervals until month 3. For analysis of the acute and prolonged effects, the plasma levels of nt-BNP and nt-ANP were determined before and after each IA course. In 15 comparable DCM patients (controls), plasma levels of nt-BNP and nt-ANP were determined at baseline and after 3 months. LVEF remained stable during this study in the control group. In contrast, in the IA group after 3 months, LVEF increased from 29.7 +/- 1 to 38.6 +/- 2%, P < 0.001. In the control group, the nt-BNP and nt-ANP plasma levels remained stable during the 3 months of the study. In the IA group after the first IA course, the level of nt-BNP was acutely reduced from 1501 +/- 328 to 925 +/- 151 fmol/mL, P < 0.01. In addition, the nt-ANP level was reduced from 4439 +/- 1271 to 2897 +/- 825 fmol/mL, P < 0.01. In the IA group, the reduction of these two parameters remained detectable after 3 months before the last course: nt-BNP: 714 +/- 119 fmol/mL, nt-ANP: 2227 +/- 427 fmol/mL, P < 0.05. The improvement of left ventricular function during IA is accompanied by a reduction of nt-BNP and nt-ANP plasma levels in patients with DCM.

Clopidogrel Is Associated With a Lesser Increase in NT-proBNP When Compared to Aspirin in Patients With Ischemic Heart Failure

BACKGROUND

Aspirin has been associated with adverse heart failure outcomes, probably because of a blunting interaction with angiotensin-converting enzyme (ACE) inhibitors. Therefore, we hypothesized that clopidogrel when compared with aspirin would be associated with a slower progression of heart failure as determined by levels of amino-terminal pro-brain natriuretic peptide (NT-proBNP).

METHODS AND RESULTS

In an open-label, randomized, 2-treatment, 2-period crossover study, 18 patients with ischemic heart failure (14 post-myocardial infarction, left ventricular ejection fraction 0.32 +/- 0.08), median age 73, New York Heart Association class II (11 patients) or III (7 patients), all taking ACE inhibitors were included. Patients were randomized to 8 weeks of aspirin 100 mg/day followed by 8 weeks of clopidogrel 75 mg/day, or the reversed sequence. Blood levels of NT-proBNP were measured using sandwich immunoassay. Patients on aspirin experienced an 8-times greater increase in log-transformed values of NT-proBNP compared with patients on clopidogrel (average change 4.757% versus 0.597%; P = .0395 for intervention, P = .4453 for period, P = .4046 for sequence). We observed no change in functional class, 6-minute walking test, creatinine levels, or electrolytes.

CONCLUSION

Aspirin is associated with a greater increase in natriuretic peptides (log-transformed NT-proBNP levels), implying that aspirin therapy is associated with a more progressive course of heart failure.

Brain natriuretic peptide (BNP) testing in the emergency department

In the past decade a large amount of attention has been focused on brain natriuretic peptide (BNP) testing in the evaluation of patients with acute dyspnea as well as the screening of patients for congestive heart failure (CHF). Because BNP is secreted by myocytes in response to ventricular stretch, it has long been thought that BNP could become a biochemical marker for CHF. Rapid assays have been developed and BNP testing has been studied in detection of CHF and predictive outcomes in a large variety of settings. We review the clinical evidence associated with the use of BNP testing in the acute care setting. We conclude with a discussion of clinical utility in the emergency department for the evaluation of patients presenting with acute dyspnea.

Beneficial effects of add-on hydrochlorothiazide in rats with myocardial infarction optimally treated with quinapril

BACKGROUND

The antihypertensive and renoprotective effects of ACE inhibitor (ACEi) therapy are enhanced by inducing a negative sodium balance. Whether this strategy also improves outcome of chronic ACEi treatment after myocardial infarction (MI) is unknown. Therefore, we investigated whether hydrochlorothiazide (HCTZ) or dietary sodium restriction further improves survival in ACEi-treated rats with MI.

METHODS

MI was induced by coronary ligation. After 2 weeks rats were randomised to quinapril (QUI), HCTZ added to quinapril (QUI+HCTZ), or low sodium diet added to quinapril (QUI+LS). Survival was monitored for 62 weeks, after which left ventricular (LV) pressures were measured and blood for neurohumoral characterisation was collected. A separate group of rats, subjected to the same procedure, was evaluated after 35 weeks.

RESULTS

After 62 weeks, mortality was comparable in all groups. However, survival was improved by HCTZ until 35 weeks. This effect on survival was paralleled by decreased proteinuria and LV end-diastolic pressures in QUI+HCTZ rats at 35, but not 62 weeks. Plasma renin activity was significantly decreased in QUI+HCTZ rats at 35 weeks. Contrary to HCTZ, LS added to QUI caused no benefit.

CONCLUSIONS

Adding HCTZ, but not LS, to quinapril improved survival, neurohumoral status, and proteinuria during the early chronic phase of experimental post-MI LV dysfunction. Since no adverse effects were observed, HCTZ may safely be used to improve ACEi therapy.

BNP--Considering a heartfelt message

The natriuretic hormones have been discovered as mediators of the cardiac response to volume overload and mechanical dysfunction. Although there are some physiological differences between atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), it is BNP that has been found to be most useful as a clinical test. BNP is secreted along with an N terminal proBNP cleavage product (NT-proBNP). The similarities between these two tests are far greater than the differences. They are both probably useful in the diagnosis of high-risk patients (e.g. dyspnoeic) and may be useful in monitoring cardiac failure treatment. Although BNP levels in the normal range predict the risk of cardiac events and mortality, there is little evidence to promote their use as a screening test. In such an important condition as cardiac failure we should consider any messages that are likely to be of value, particularly those that are heartfelt.

Brain natriuretic peptide and optimal management of heart failure

Aside from the important role of brain natriuretic peptide (BNP) in diagnosis, and differential diagnosis of heart failure, this biological peptide has proved to be an independent surrogate marker of rehospitalization and death of the fatal disease. Several randomized clinical trials demonstrated that drugs such as beta blocker, angiotensin converting enzyme inhibitor, spironolactone and amiodarone have beneficial effects in decreasing circulating BNP level during the management of chronic heart failure. The optimization of clinical decision-making appeals for a representative surrogate marker for heart failure prognosis. The serial point-of-care assessments of BNP concentration provide a therapeutic goal of clinical multi-therapy and an objective guidance for optimal treatment of heart failure. Nevertheless new questions and problems in this area remain to be clarified. On the basis of current research advances, this article gives an overview of BNP peptide and its property and role in the management of heart failure.

Novel markers for heart failure diagnosis and prognosis

PURPOSE OF REVIEW

This paper reviews recent advances in heart failure biomarkers for identification of disease precursors, subclinical disease, and onset or progression of overt disease.

RECENT FINDINGS

Heart failure biomarkers can be categorized empirically as neurohormonal mediators, markers of myocyte injury and remodeling, and indicators of systemic inflammation. Brain natriuretic peptide is the most widely studied, with a potentially important but evolving role for determining prognosis and as a surrogate endpoint in clinical trials. Strong evidence exists for use of brain natriuretic peptide in the diagnosis of acute heart failure and for improved clinical outcomes with a brain natriuretic peptide-guided approach to heart failure care. The use of brain natriuretic peptide as a screening tool for asymptomatic left ventricular systolic dysfunction, or to distinguish systolic from diastolic heart failure, is not supported by current data. Markers of myocyte injury, including troponins, heart-type fatty acid binding protein, and myosin light chain-1, may further improve heart failure prognostication in conjunction with plasma brain natriuretic peptide. Biomarkers of matrix remodeling and inflammation have emerged as potential preclinical indicators to identify individuals at risk of developing clinical heart failure. A role for cellular adhesion molecules may also emerge in identifying those at risk for cardiovascular thrombotic complications, such as stroke.

SUMMARY

The spectrum of heart failure biomarkers and their potential clinical applications continues to grow. Ongoing research on multimarker strategies will likely identify biomarker combinations that are optimal at various stages during the evolution of heart failure, ranging from their use for screening, diagnosis, determining prognosis, and guiding management.

Consistency of the beneficial effect of metoprolol succinate extended release across a wide range dose of angiotensin-converting enzyme inhibitors and digitalis

BACKGROUND

The effects of beta-blockade with different extent of angiotensin-converting enzyme inhibitors (ACEI) and digitalization are unknown. To assess the effect of metoprolol succinate controlled release/extended release (CR/XL) combined with high versus low doses of ACEI and digitalis, we analyzed data from The Metoprolol CR/XL Randomized Intervention Trial in Chronic Heart Failure (MERIT-HF) in which patients with heart failure and left ventricular ejection fraction < or =40% were randomized to metoprolol CR/XL versus placebo.

METHODS AND RESULTS

Outcome was analyzed separately for those on a low dose (< or =median) of the ACEI or digitalis versus high dose (> median). The mean dose of ACEI in the high-dose group (n = 1457) was 3 times higher than that in the low-dose group (n = 2094). Mortality was reduced to a similar extent in the high- and low-dose ACEI subgroups (RR = .69 versus .64, respectively). Corresponding figures for combined mortality/all hospitalization and for mortality/hospitalization for heart failure were .85 versus .83, and .70 versus .68, respectively. Likewise, reduction in total mortality with metoprolol CR/XL was similar in patients receiving no digitalis (n = 1447; RR = .56), low dose (n = 1122; RR = .71), or high dose (n = 1421; RR = .71).

CONCLUSION

This analysis of MERIT-HF demonstrates consistent and similar improvement in outcome of patients receiving metoprolol CR/XL when combined with either a high or low dose of an ACEI or digitalis, or no digitalis at all. Thus regardless of ACEI and digitalis dose and whether patients are treated with digitalis or not, it is very important to add a beta-blocker to the existing heart failure therapy. beta-blockers should not be withheld until target doses of ACEI have been achieved.

A meta-analysis of the effect of angiotensin-converting enzyme inhibitors on functional capacity in patients with symptomatic left ventricular systolic dysfunction

AIM

To determine by meta-analysis whether angiotensin-converting enzyme (ACE) inhibitors improve exercise tolerance in patients with symptomatic left ventricular systolic dysfunction (LVSD).

METHODS AND RESULTS

After literature search 13 multi-centre double blind parallel group trials that evaluated the effect of ACE inhibitors vs. placebo on exercise duration were selected. Ninety-four percent of patients were in New York Heart Association class II-IV. The studies were combined using the Cochrane meta-analysis program (Review manager version 4.1). Analyses according to treatment period, exercise protocols and publication periods were performed. Treatment with ACE inhibitor over 4-12 weeks resulted in a beneficial effect on exercise duration (P=0.003 and P=0.0008 for 4- and 12-weeks treatment, respectively), but the magnitude of improvements did not exceed 30 s corresponding to only 5% compared with placebo.

CONCLUSION

In addition to the pronounced effect on mortality and morbidity in patients with symptomatic LVSD, ACE inhibitors have improving effect on functional capacity measured as exercise tolerance time.

[Brain natriuretic peptide and heart failure, from bench to bedside]

Diagnosing or managing heart failure may still remain difficult. BNP and NT proBNP are neurohormones specifically secreted by myocytes. They have proved their effectiveness to improve clinician's diagnostic accuracy for diagnosing heart failure. BNP use is now recommended by European Society of Cardiology guidelines but multiplication of publications about BNP and NTProBNP show new possible applications for natriuretic peptides.

Pharmacogenetic interactions between angiotensin-converting enzyme inhibitor therapy and the angiotensin-converting enzyme deletion polymorphism in patients with congestive heart failure

OBJECTIVES

We evaluated the interaction of angiotensin-converting enzyme (ACE) inhibitor therapy with the effect of the ACE D/I polymorphism on heart failure survival.

BACKGROUND

The ACE deletion allele, ACE-D, is associated with increased ACE activity. The utilization of ACE genotyping to predict the impact of ACE inhibitor dose has not been previously evaluated.

METHODS

We prospectively studied 479 subjects with systolic dysfunction (left ventricular ejection fraction 0.25 +/- 0.08). Subjects were divided on the basis of ACE inhibitor therapy into low dose (<or=50% of target dose, n = 227), standard (high) dose (>50%, n = 201), or those receiving angiotensin receptor antagonists (n = 51). Patients were genotyped for the ACE D/I polymorphism, followed to the end point of death or cardiac transplantation, and transplant-free survival compared by genotype.

RESULTS

The ACE-D allele was associated with an increased risk of events (p = 0.026). In analysis by ACE inhibitor dose, this effect was primarily in the low-dose group (1-year percent event-free survival: II/ID/DD = 86/77/71,2-year = 79/66/59, p = 0.032). In the standard-dose group, the impact was markedly diminished (1-year: II/ID/DD = 91/81/80, 2-year: 77/70/71, p = 0.64). The impact of beta-blockers and high dose ACE inhibitors was greatest in subjects with the ACE DD genotype (p = 0.001) and was less apparent with the II and ID genotypes (p = 0.38).

CONCLUSIONS

Higher doses of ACE inhibitors diminished the impact of the ACE-D allele, and the benefits of beta-blockers and high-dose ACE inhibitors appeared maximal for DD patients. Determination of ACE genotype may help target therapy for patients with heart failure.

High Intraindividual Variation of B-Type Natriuretic Peptide (BNP) and Amino-Terminal proBNP in Patients with Stable Chronic Heart Failure

Background: Plasma B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are promising markers for heart failure diagnosis, prognosis, and treatment. Insufficient data on the intraindividual biological variation (CVi) of BNP and NT-proBNP hamper interpretation of changes in concentration on disease progression or treatment optimization. We therefore investigated CVi values in stable heart failure patients.

Methods: We recruited 43 patients with stable chronic heart failure living in Curaçao (22 males, 21 females; median age, 63 years; range, 20–86 years; New York Heart Association classes I–III). Samples were collected for within-day CVi (n = 6; every 2 h starting at 0800), day-to-day CVi (n = 5; samples collected between 0800 and 1000 on 5 consecutive days), and week-to-week CVi (n = 6; samples collected between 0800 and 1000 on the same day of the week for 6 consecutive weeks). NT-proBNP (Roche) and BNP (Abbott) were measured by immunoassay.

Results: Median (range) concentrations were 134 (0–1630) ng/L (BNP) and 570 (17–5048) ng/L (NT-proBNP). Analytical variation, week-to-week CVi, and reference change values were 8.4%, 40%, and 113% (BNP), and 3.0%, 35%, and 98% (NT-proBNP). Week-to week CVis were inversely related to median BNP concentrations. Week-to week CVis for BNP were 44% (BNP ≤350 ng/L) and 30% (BNP &gt;350 ng/L). Both BNP and NT-proBNP increased between 0800 and 1000. Median NT-proBNP/BNP ratios were inversely related to median BNP concentrations.

Conclusions: The high CVis hamper interpretation of changes in BNP and NT-proBNP concentrations and may partly explain their poor diagnostic values in chronic heart failure. Easily modifiable determinants to lower CVi have not been identified. The value of BNP and NT-proBNP for chronic heart failure diagnosis, and especially for follow-up and treatment optimization of individuals, remains largely to be established.