Importance of neuroendocrine activation in chronic heart failure. Impact on treatment strategies

Upregulated expression of a TOR2A gene product-salusin-β in the paraventricular nucleus enhances sympathetic activity and cardiac sympathetic afferent reflex in rats with chronic heart failure induced by coronary artery ligation

AIM

Enhanced cardiac sympathetic afferent reflex (CSAR) promotes sympathetic hyperactivation in chronic heart failure (CHF). Salusin-β is a torsin family 2 member A (TOR2A) gene product and a cardiovascular active peptide closely associated with cardiovascular diseases. We aimed to determine the roles of salusin-β in the paraventricular nucleus (PVN) in modulating enhanced CSAR and sympathetic hyperactivation in rats with CHF induced by coronary artery ligation and elucidate the underlying molecular mechanisms.

METHODS

CSAR was evaluated based on the responses of mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) to the epicardial administration of capsaicin in rats under anesthesia.

RESULTS

Salusin-β protein expression was upregulated in the PVN of the CHF compared with sham-operated rats. Salusin-β microinjection into the PVN dose-dependently increased MAP and RSNA and enhanced CSAR, while anti-salusin-β IgG exerted opposite effects. The effect of salusin-β was inhibited by reactive oxygen species (ROS) scavenger or NAD(P)H oxidase inhibitor but promoted by superoxide dismutase inhibitor. The effect of anti-salusin-β IgG was interdicted by nitric oxide (NO) synthase inhibitor. Furthermore, chronic salusin-β gene knockdown in PVN attenuated CSAR, reduced sympathetic output, improved myocardial remodeling and cardiac function, decreased NAD(P)H oxidase activity and ROS levels, and increased NO levels in the CHF rats.

CONCLUSION

Increased salusin-β activity in the PVN contributes to sympathetic hyperactivation and CSAR in CHF by inhibiting NO release and stimulating NAD(P)H oxidase-ROS production. Reducing endogenous central salusin-β expression might be a novel strategy for preventing and treating CHF in the future.

Global historical retrospect and future prospects on biomarkers of heart failure: A bibliometric analysis and science mapping

Introduction

Heart failure is a rapidly growing public health problem and has become a major cause of hospitalization in middle-aged and older adults. Biomarkers are clinically important in managing heart failure and have attracted more attention from researchers in recent years. This study aimed to evaluate the global research of heart failure biomarkers by bibliometrics and to identify the hot spots and perspectives for further advancement.

Methods

Selection of relevant documents was from the Web of Science Core Collection. Microsoft Excel, VOSviewer, SciMA, and CiteSpace software were used for bibliometric analysis.

Results

As of October 29, 2021, 5,978 documents for heart failure biomarkers have been identified from 1989 to 2021. European Journal of Heart Failure and Circulation respectively ranked first in terms of the number of publications and the number of co-citations. A total of 5,698 institutions from 90 countries participated in these publications, with the USA leading with 2,045 documents. The most productive institution was Harvard University. Januzzi, J.L. and Maisel, A.S. were the most productive and most cited authors respectively. Natriuretic peptide, copeptin, valsartan, ferric carboxymaltose, empagliflozin, preserved ejection fraction, myocardial fibrosis, and heart transplantation were hot themes.

Conclusions

Extensive national and inter-institutional collaboration should be enhanced to bridge the gap between developed and less developed countries in heart failure biomarkers research. The research in this field seems to have reached a relatively mature stage, with a decrease in research fervor in recent years. The study of the natriuretic peptide family still has high centrality, with advances in the study of expression products and inflammatory markers. Cardiac fibrosis, cardiac remodeling, and therapies regarding heart failure have become hot spots.

Gliflozins: From Antidiabetic Drugs to Cornerstone in Heart Failure Therapy-A Boost to Their Utilization and Multidisciplinary Approach in the Management of Heart Failure

Heart failure (HF) is a complex, multifactorial, progressive clinical condition affecting 64.3 million people worldwide, with a strong impact in terms of morbidity, mortality and public health costs. In the last 50 years, along with a better understanding of HF physiopathology and in agreement with the four main models of HF, many therapeutic options have been developed. Recently, the European Society of Cardiology (ESC) HF guidelines enthusiastically introduced inhibitors of the sodium-glucose cotransporter (SGLT2i) as first line therapy for HF with reduced ejection fraction (HFrEF) in order to reduce hospitalizations and mortality. Despite drugs developed as hypoglycemic agents, data from the EMPA-REG OUTCOME trial encouraged the evaluation of the possible cardiovascular effects, showing SGLT2i beneficial effects on loading conditions, neurohormonal axes, heart cells' biochemistry and vascular stiffness, determining an improvement of each HF model. We want to give a boost to their use by increasing the knowledge of SGLT2-I and understanding the probable mechanisms of this new class of drugs, highlighting strengths and weaknesses, and providing a brief comment on major trials that made Gliflozins a cornerstone in HF therapy. Finally, aspects that may hinder SGLT2-i widespread utilization among different types of specialists, despite the guidelines' indications, will be discussed.

Promising directions in the treatment of chronic heart failure: improving old or developing new ones?

Unprecedented advances of recent decades in clinical pharmacology, cardiac surgery, arrhythmology, and cardiac pacing have significantly improved the prognosis in patients with chronic heart failure (CHF). However, unfortunately, heart failure continues to be associated with high mortality. The solution to this problem consists in simultaneous comprehensive use in clinical practice of all relevant capabilities of continuously improving methods of heart failure treatment proven to be effective in randomized controlled trials (especially when confirmed by the results of studies in real clinical practice), on the one hand, and in development and implementation of innovative approaches to CHF treatment, on the other hand. This is especially relevant for CHF patients with mildly reduced and preserved left ventricular ejection fraction, as poor evidence base for the possibility of improving the prognosis in such patients cannot justify inaction and leaving them without hope of a clinical improvement in their condition. The lecture consistently covers the general principles of CHF treatment and a set of measures aimed at inotropic stimulation and unloading (neurohormonal, volumetric, hemodynamic, and immune) of the heart and outlines some promising areas of disease-modifying therapy.

Assessment of sacubitril/valsartan effects on left ventricular dynamics using 3D echocardiography and 3D strain in heart failure with reduced ejection fraction patients

BACKGROUND

Three-dimensional (3D) echocardiography and 3D strain parameters have been used for a comprehensive quantitative assessment of left ventricular (LV) myocardial dynamics. So far, there are no data on sacubitril/valsartan effects on cardiac functions and LV reverse remodeling using 3D echocardiography. This study aimed to evaluate the effects of sacubitril/valsartan on the LV functions using two-dimensional (2D) echocardiography, 3D echocardiography, and the 3D strain parameters.

METHODS

A single-center prospective cohort study which included 100 heart failure with reduced ejection fraction (HFrEF) patients with guidelines-approved indications for sacubitril/valsartan treatment. Patients received a short course (3-month) of sacubitril/valsartan. 3-month follow-up 2D, 3D echocardiographic parameters, and 3D strain were compared to baseline parameters.

RESULTS

The results of the study revealed a significant improvement in left ventricular dynamic functions at 3-month follow-up with an improvement in left ventricular systolic function (mean left ventricular ejection fraction (LVEF) increased from 27.65 ± 4.98% to 32.89 ± 6.03%, P<0.001). Comparison of HFrEF patients with ischemic and non-ischemic etiologies showed that echocardiographic parameters significantly improved in both groups after 3 months of sacubitril/valsartan treatment. There was no statistically significant difference between both groups regarding echocardiographic parameters at baseline and 3-month follow-up.

CONCLUSIONS

In a single-center prospective observational cohort study evaluating the effects of short-term (3-month course) sacubitril/valsartan treatment on LV dynamics assessed by 3D echocardiography and 3D strain, sacubitril/valsartan was associated with a significant improvement of LV systolic functions and reverse remodeling effects in both ischemic and non-ischemic HFrEF patients.

Knockdown of Salusin-β Improves Cardiovascular Function in Myocardial Infarction-Induced Chronic Heart Failure Rats

Salusin-β is a biologically active peptide with 20 amino acids that exerts several cardiovascular activity-regulating effects, such as regulating vascular endothelial function and the proliferation of vascular smooth muscle cells. However, the regulatory effects of salusin-β in myocardial infarction-induced chronic heart failure (CHF) are still unknown. The current study is aimed at investigating the effects of silencing salusin-β on endothelial function, cardiac function, vascular and myocardial remodeling, and its underlying signaling pathways in CHF rats induced by coronary artery ligation. CHF and sham-operated (Sham) rats were subjected to tail vein injection of adenoviral vectors encoding salusin-β shRNA or a control-shRNA. The coronary artery (CA), pulmonary artery (PA), and mesenteric artery (MA) were isolated from rats, and isometric tension measurements of arteries were performed. Compared with Sham rats, the plasma salusin-β, leptin and visfatin levels and the salusin-β protein expression levels of CA, PA, and MA were increased, while the acetylcholine- (ACh-) induced endothelium-dependent vascular relaxation of CA, PA, and MA was attenuated significantly in CHF rats and was improved significantly by salusin-β gene knockdown. Salusin-β knockdown also improved cardiac function and vascular and myocardial remodeling, increased endothelial nitric oxide synthase (eNOS) activity and nitric oxide (NO) levels, and decreased NAD(P)H oxidase activity, NOX-2 and NOX-4 expression, and reactive oxygen species (ROS) levels in arteries in CHF rats. The effects of salusin-β knockdown in CHF rats were attenuated significantly by pretreatment with the NOS inhibitor L-NAME. These results indicate that silencing salusin-β contributes to the improvement of endothelial function, cardiac function, and cardiovascular remodeling in CHF by inhibiting NAD(P)H oxidase-ROS generation and activating eNOS-NO production.

Renal and intraglomerular haemodynamics in chronic heart failure with preserved and reduced ejection fraction

AIMS

Congestive heart failure (CHF) and impaired renal function are two often co-existing medical conditions and associated with adverse cardiovascular outcome. The aim of the current study was to assess renal and intraglomerular haemodynamics by constant infusion input clearance technique in subjects with CHF.

METHODS AND RESULTS

The group of subjects with CHF consisted of 27 individuals with HFpEF and 27 individuals with HFrEF and were compared with 31 healthy controls. Subjects underwent renal clearance examination to measure glomerular filtration rate (GFR) and renal blood and plasma flow (RBF and RPF) and to calculate intraglomerular haemodynamics such as resistances of the afferent (RA ) and efferent arterioles (RE ) as well as intraglomerular pressure (Pglom ). Measured GFR was lower in CHF subjects (68.1 ± 10.1 mL/min/1.73 m2 ) compared with controls (83.6 ± 13.4 mL/min/1.73 m2 , Padj  < 0.001) as was Pglom (Padj  < 0.001). Total renal vascular resistance (RVR) was higher in CHF subjects (87.3 ± 20.1 vs. 73.8 ± 17.1 dyn × s/cm5 , Padj  < 0.001) mediated by an increased resistance at the afferent site (3201 ± 1084 vs. 2181 ± 796 dyn × s/cm5 , Padj  < 0.001). Comparing HFpEF and HFrEF subjects, RA was higher in HFrEF subjects. The severity of CHF assessed by NT-proBNP revealed an inverse association with renal perfusion (RPF r = -0.421, P = 0.002, RBF r = -0.414, P = 0.002) and a positive relation with RVR (r = 0.346, P = 0.012) at the post-glomerular site (RE : r = 0.318, P = 0.022).

CONCLUSIONS

Renal function assessed by measured GFR is reduced and renal vascular resistance at the preglomerular, afferent site is increased in HFpEF and, to greater extent, in HFrEF. Our data indicate a close cardiorenal interaction in CHF.

PHYSICAL CAPACITY, RESPIRATORY AND PERIPHERAL MUSCLE STRENGTH IN HEART FAILURE

ABSTRACT Introduction The Glittre-ADL test is a submaximal test that involves sitting/lifting, stair climbing/descending, and weight-bearing activities, with considerable potential for use in assessing exercise intolerance in heart failure. Objectives To investigate the influence of heart failure on maximal physical (ergometric test - ET) and functional (6MWT and Glittre-ADL test) capacity, on respiratory (IPmax and EPmax) and peripheral (handgrip strength) muscle strength, and to study the correlation between the variables evaluated. Methods A prospective comparative study that assessed 44 subjects divided into two groups: G1, with 26 heart patients (20 men/6 women, 65.26 ± 8.50 years), and G2, with 18 healthy subjects paired with G1 on the basis of sex ratio, age and anthropometric characteristics (10 men/8 women, 60.72 ± 8.39 years). The comparison of categorical variables was performed using the chi-square test, while continuous variables were compared using the Student t test or Mann-Whitney test. The study of the correlation between variables was conducted using the Pearson coefficient for EPmax and handgrip strength, while the Spearman correlation coefficient was used for the others, with a statistical significance level of 5%. Results Groups were homogeneous in terms of sex ratio, age and anthropometric characteristics. G1 had a worse performance in all tests: ET (p = 0.016), Glittre-ADL (p = 0.001), 6MWT (p = 0.001), IPmax (p = 0.012), EPmax (p = 0.007) and handgrip strength (p = 0.036). There was a negative correlation between the Glittre-ADL test and 6MWT, and the Glittre-ADL test and handgrip strength in G1. Conclusion Heart failure resulted in impairment of maximal physical and functional capacity and of respiratory and peripheral muscle strength, with a negative correlation between functional capacity and handgrip strength. Level of evidence II; Prospective comparative study.

Dual angiotensin receptor and neprilysin inhibition as an alternative to angiotensin-converting enzyme inhibition in patients with chronic systolic heart failure: rationale for and design of the Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortality and morbidity in Heart Failure trial (PARADIGM-HF)

AIMS

Although the focus of therapeutic intervention has been on neurohormonal pathways thought to be harmful in heart failure (HF), such as the renin-angiotensin-aldosterone system (RAAS), potentially beneficial counter-regulatory systems are also active in HF. These promote vasodilatation and natriuresis, inhibit abnormal growth, suppress the RAAS and sympathetic nervous system, and augment parasympathetic activity. The best understood of these mediators are the natriuretic peptides which are metabolized by the enzyme neprilysin. LCZ696 belongs to a new class of drugs, the angiotensin receptor neprilysin inhibitors (ARNIs), which both block the RAAS and augment natriuretic peptides.

METHODS

Patients with chronic HF, NYHA class II-IV symptoms, an elevated plasma BNP or NT-proBNP level, and an LVEF of ≤40% were enrolled in the Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortailty and morbidity in Heart Failure trial (PARADIGM-HF). Patients entered a single-blind enalapril run-in period (titrated to 10 mg b.i.d.), followed by an LCZ696 run-in period (100 mg titrated to 200 mg b.i.d.). A total of 8436 patients tolerating both periods were randomized 1:1 to either enalapril 10 mg b.i.d. or LCZ696 200 mg b.i.d. The primary outcome is the composite of cardiovascular death or HF hospitalization, although the trial is powered to detect a 15% relative risk reduction in cardiovascular death.

PERSPECTIVES

PARADIGM-HF will determine the place of the ARNI LCZ696 as an alternative to enalapril in patients with systolic HF. PARADIGM-HF may change our approach to neurohormonal modulation in HF.

TRIAL REGISTRATION

NCT01035255.

Cytokines, interstitial collagen and ventricular remodelling in dilated cardiomyopathy

BACKGROUND

Dilated cardiomyopathy (DCM) is associated with myocardial fibrosis, and proinflammatory cytokines may play a role in this.

METHODS

N-terminal type I and III procollagen propeptides (PINP, PIIINP) and cross-linked telopeptide of type I collagen (ICTP) were measured from serum samples of 73 patients with DCM and 56 age and sex matched controls. Circulating cytokine levels were determined in DCM patients.

RESULTS

Serum levels of PINP and PIIINP were lower in patients than in controls (p<0.05 and p=0.001). In patients with DCM, the levels of PIIINP and ICTP correlated significantly with each other (p<0.01), and the proinflammatory cytokines, tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6), correlated positively with ICTP (p<0.001, p<0.05), PIIINP/PINP ratio (p<0.05, p<0.01) and left atrial size (p<0.01, p<0.05). Presence of atrial fibrillation was associated with lower serum PINP level and higher PIIINP/PINP ratio (p<0.05).

CONCLUSIONS

Our results suggest that interstitial myocardial collagen metabolism is altered in DCM patients and regulated by proinflammatory cytokines. These changes in collagen metabolism are associated with presence of atrial fibrillation, but do not reflect left ventricular remodelling. Treatment with beta-blockers and inhibitors of the renin angiotensin aldosterone system seem to effectively inhibit overall type I and III collagen syntheses.

Cardiovascular profile of the canine torsades de pointes arrhythmia model assessed by echocardiographic and haemodynamic methods

Chronic atrioventricular block dogs have been established as an in vivo model of drug-induced torsades de pointes arrhythmias. We compared the cardiovascular profile of the canine model with that of sham-operated animals using echocardiographic and haemodynamic methods. In the echocardiographic study, the larger diameters of the left atria, inferior vena cava and left ventricle in end-diastole in addition to greater fractional shortening, end-diastolic volume, stroke volume and ejection fraction were more often detected in the chronic atrioventricular block dogs than in the sham-operated animals. During haemodynamic examination, lower cardiac output and higher pulmonary capillary wedge pressure were detected in chronic atrioventricular block dogs more than in sham-operated animals; however, these changes were within the physiological limits, and the results suggest that the chronic atrioventricular block dogs have a pathophysiological profile of chronic compensated heart failure.

Prognostic importance of plasma NT-pro BNP in chronic heart failure in patients treated with a β-blocker: Results from the Carvedilol Or Metoprolol European Trial (COMET) trial

BACKGROUND

Plasma levels of N-terminal pro-brain natriuretic peptide (NT-pro BNP) are increased in patients with chronic heart failure (CHF). Beta-blockers (BB) may influence these levels but it is unclear whether changes in NT-pro BNP reflect concomitant changes in prognosis.

OBJECTIVES

To assess the prognostic importance of NT-pro BNP at baseline and during follow-up, in patients in whom beta-blocker therapy is initiated.

METHODS

In COMET, 3029 patients with CHF in NYHA class II-IV and EF<35% were randomised to carvedilol or metoprolol tartrate and were followed for an average of 58 months. Blood samples were collected for the measurement of NT-pro BNP at baseline (n=1559) and during follow-up (n=309).

RESULTS

Baseline plasma concentrations of NT-pro BNP above the median (1242 pg/ml) were associated with higher all-cause mortality (RR 2.77; 95% CI 2.33-3.3, p<0.001). Patients who achieved NT-pro BNP levels<400 pg/ml during follow-up had a lower subsequent mortality (RR 0.32; 95% CI 0.15-0.69, p=0.004).

CONCLUSIONS

The plasma concentration of NT-pro BNP is a powerful predictor of mortality in patients with CHF. Patients who achieve an NT-pro BNP of <400 pg/ml subsequent to treatment with a beta-blocker have a favourable prognosis.

β-blocker therapy of heart failure: an update

The beneficial effects of beta-blocker therapy in patients with heart failure have been consistently shown by multi-center randomised trials. These agents are effective and also relatively well tolerated in the elderly and in patients with diabetes and advanced heart failure--traditionally considered as relative contraindications to their administration. However, the use of beta-blockers in clinical practice remains low. The difficulties in their initiation and up-titration may be overcome by patient and physician education, as well as by their initiation during hospitalisation and/or the involvement of non-physician providers (i.e., a nurse facilitator). Forthcoming advances in the pharmacokinetic and pharmacodynamic characteristics of some beta-blockers, and testing of novel methods for patient and drug selection may be based on genetic testing, and may allow further improvement of beta-blocker therapy in the next future.

Pharmacological treatment of chronic heart failure

Heart failure (HF) is associated with a high morbidity and mortality in the Western World. Our knowledge of the epidemiology, pathophysiology, and therapy has improved dramatically during the last 20 years. Pharmacological treatment, as it stands today, is a combination of preventive and symptomatic strategies. The mainstay life-saving drugs are angiotensin-converting enzyme inhibitors and beta-blockers. Additional benefits are obtained when angiotensin-receptor blockers or aldosterone antagonists are added. Digitalis and/or diuretics are useful for symptom reduction. In addition, combination therapy with hydralazine and isosorbide dinitrate is recommended in African Americans.

Prevention and management of chronic heart failure in management of asymptomatic patients

Symptomatic heart failure is preceded by a somewhat prolonged asymptomatic stage in many patients. The number of patients with asymptomatic heart dysfunction is about 4-fold greater than the number of patients with clinically overt heart failure. Pharmacologic treatment with angiotensin-converting enzyme inhibitors and beta-blockers (in particular carvedilol) of asymptomatic patients with systolic left ventricular (LV) dysfunction can prevent or delay the occurrence of symptoms and reduce mortality in the long term. Thus, it would be of utmost importance to recognize and appropriately treat these patients before they develop heart failure symptoms. The cost-effectiveness of screening for asymptomatic heart dysfunction in the general population and in cohorts at risk has not been extensively evaluated. A normal electrocardiogram has a high negative predictive value in patients at risk. Echocardiography is the best tool for diagnosis and characterization of heart dysfunction, but extensive use is limited by availability and cost. Natriuretic peptides (brain natriuretic peptide and N-terminal pro-brain natriuretic peptide) are very sensitive markers of heart dysfunction and volume overload, and their measurement has been proposed as a first-line test to select patients who need echocardiography. The definition of the etiology of LV dysfunction--in particular, of the ischemic etiology--has prognostic and therapeutic implications. In addition to revascularization, pharmacologic treatment with antiplatelets and statins is helpful in preventing new ischemic events and the development of heart failure. The prevention, or at least the delay, of clinical manifestations of heart failure is strongly related to an effective approach to the asymptomatic stage. Therefore, it is important to educate the entire medical community, particularly physicians in the primary care setting, about recognition and treatment of these patients.

Preservation of the baroreceptor heart rate reflex by chemical sympathectomy in experimental heart failure

BACKGROUND

The mechanisms underlying impaired baroreflex sensitivity in congestive heart failure (CHF) are incompletely understood. The purpose of the present study was to test the hypothesis that this alteration depends on the marked degree of sympathetic overactivity known to characterize the CHF syndrome.

METHODS AND RESULTS

Eight-week-old rats were subjected to induction of postmyocardial infarction CHF obtained by coronary ligation (Lig), chronic chemical sympathectomy by 6-hydroxydopamine (Sx), both interventions (Sx-Lig), or neither intervention (Veh-Sham, sham surgery, and vehicle administration). Four weeks after infarction, in conscious state, baroreflex sensitivity was assessed from the bradycardic responses to graded phenylephrine-induced elevations in blood pressure (BP). Left ventricular (LV) diameter was assessed by echocardiography, and plasma catecholamines were assayed to estimate sympathetic activity. Lungs were eventually excised and weighed (LW). CHF was associated with the following: (1) no changes in BP and heart rate; (2) sympathetic overactivity (norepinephrine, 320.2+/-53.8 pg/mL for Veh-Lig versus 173.4+/-20.5 pg/mL for Veh-Sham, P<0.01), prevented by Sx (181.2+/-35.5 pg/mL for Sx-Lig versus 159.8+/-33.1 pg/mL for Sx-Sham, P=NS); (3) LV enlargement (10.3+/-0.7 mm for Veh-Lig versus 6.8+/-0.6 mm for Veh-Sham, P<0.01), irrespective of Sx (9.7+/-0.7 mm for Sx-Lig versus 6.6+/-0.5 mm for Sx-Sham, P<0.01); (4) pulmonary congestion (LW, 7.55+/-0.40 mg per gram of body weight for Veh-Lig versus 5.21+/-0.44 mg per gram of body weight for Veh-Sham, P<0.01), marginally attenuated by Sx (6.54+/-0.28 mg per gram of body weight for Sx-Lig versus 4.98+/-0.22 mg per gram of body weight for Sx-Sham, P<0.05); (5) reduction in baroreflex sensitivity (0.443+/-0.032 ms/mm Hg for Veh-Lig versus 0.860+/-0.420 ms/mm Hg for Veh-Sham, P<0.01), entirely prevented by Sx (1.217+/-0.058 ms/mm Hg for Sx-Lig versus 1.345+/-0.093 ms/mm Hg for Sx-Sham, P=NS).

CONCLUSIONS

In early post-MI CHF, sympathectomy only partially attenuated LV dysfunction and entirely prevented baroreflex sensitivity impairment that arises from enhanced sympathetic activity.

Longstanding atrial fibrillation causes depletion of atrial natriuretic peptide in patients with advanced congestive heart failure

BACKGROUND

Congestive heart failure (CHF) is characterized by neurohormonal activation, including increased plasma concentrations of atrial natriuretic peptide (ANP) and N-terminal ANP (N-ANP). Onset of atrial fibrillation (AF) further increases these peptides, but it may be hypothesized that concentrations decrease during longstanding AF due to inherent atrial degeneration.

AIM

We sought to investigate the relation between neurohormonal activation in patients with CHF and the duration of concomitant AF.

METHODS

The study group comprised 60 patients (age 70 +/- 8 years) with advanced CHF due to left ventricular systolic dysfunction (left ventricular ejection fraction (LVEF) < 0.35) and chronic AF (duration 21 (1-340) months). Plasma neurohormone concentrations were measured, and multiple regression analysis was performed to identify their clinical predictors.

RESULTS

Median plasma neurohormone concentrations were: ANP 113 pmol/l, N-ANP 1187 pmol/l, norepinephrine 496 pg/ml, renin 127 micro units/l, aldosterone 128 pg/ml and endothelin 8.1 pg/ml. Norepinephrine, renin, aldosterone and endothelin were not significantly related to the duration of AF. In contrast, ANP decreased along with the duration of AF (P = 0.03), while the same trend was observed for N-ANP (P = 0.10). However, for these peptides a first order interaction with LVEF was present, which was not observed in the other neurohormones. In patients with LVEF > 0.25 ANP and N-ANP increased along with the duration of AF, whereas in patients with LVEF < or = 0.25 an inverse relation between ANP (P = 0.02) and N-ANP (P = 0.04) and the duration of AF was present, longer-standing AF being associated with lower concentrations.

CONCLUSION

In patients with advanced CHF with low LVEF plasma ANP and N-ANP concentrations decrease during longstanding AF. This finding agrees with the concept that longstanding AF leads to impaired ability of the atria to produce these neurohormones due to inherent degenerative changes.

Overview of the results of recent beta blocker trials

Results of the studies published or reported within the last 2 years provide convincing evidence that beta-blockers can decrease mortality in patients with chronic symptomatic heart failure because of left ventricular systolic dysfunction. The Cardiac Insufficiency Bisoprolol Study (CIBIS)-II and Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure (MERIT-HF) trials showed a 34% reduction in all-cause death with bisoprolol and metoprolol therapy in patients with class II-III heart failure. Data from Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS), with a 35% mortality reduction, extended this benefit to class IV patients treated with carvedilol who do not require intravenous diuretics or positive inotropes. Ongoing beta-blocker studies address new topics, such as treatment of older patients, in whom diastolic heart failure may be more common, and direct comparison of different drugs. Although the use of beta-blockers for heart failure tends to increase, implementation of the knowledge from the trials in clinical practice still remains a challenge.