Serelaxin in acute heart failure patients with and without atrial fibrillation: a secondary analysis of the RELAX-AHF trial

Characteristics and Clinical Outcomes of Patients Hospitalized for Acute Heart Failure Who Develop Atrial Fibrillation or Convert to Sinus Rhythm

BACKGROUND

Atrial fibrillation (AF) is the most common sustained arrhythmia in acute heart failure (AHF), with a prevalence of approximately 35%. However, little is known about the clinical characteristics and outcomes of in-hospital conversion from AF to sinus rhythm and vice versa.

METHODS

In a post hoc secondary analysis of the randomized, double-blind, placebo-controlled PROTECT trial in patients with AHF, we identified 4 groups of patients: AF at admission and in-hospital conversion to sinus rhythm (n = 44); in-hospital development of AF (n = 31); persistent AF (n = 278); and continuous sinus rhythm (n = 410).

RESULTS

Conversion from AF to sinus rhythm (13.7%) and from sinus rhythm to AF (7.0%) occurred only in a minority of patients. Patients with AF who converted to sinus rhythm were more often classified as being in New York Heart Association class IV, had higher heart rates and higher respiratory rates at hospital admission, whereas patients who developed AF were older, more likely to be female and had the highest ejection fractions compared to continuous sinus rhythm (all P < 0.05). Conversion to sinus rhythm or development of AF occurred mainly within the first 24 hours after hospital admission. Patients with persistent AF and those who developed AF had longer median lengths of hospital stay (8 vs 7 days; P < 0.001 and 9 vs 7 days; P < 0.001, respectively), compared to those with continuous sinus rhythm. In both univariable and multivariable analyses, there was no significant association between the AF groups and the primary clinical outcomes of either 180-day all-cause mortality or 60-day death or readmission for heart failure.

CONCLUSION

In patients hospitalized for AHF, only few converted from AF to sinus rhythm or sinus rhythm to AF. Although development of AF or persistent AF was associated with longer lengths of hospitalization, midterm mortality and readmission rates were similar in the groups.

Relaxin-2 plasma levels in atrial fibrillation are linked to inflammation and oxidative stress markers

Relaxin-2 exerts many favourable cardiovascular effects in pathological circumstances such as atrial fibrillation (AF) and heart failure, but the mechanisms underlying its actions are not completely understood. Since inflammation and fibrosis are pivotal processes in the pathogenesis of AF, our aim was to study the relationship between relaxin-2 plasma levels in left atrium (LA) and peripheral vein with molecules implicated in fibrosis, inflammation and oxidative stress in AF patients, and to evaluate the anti-fibrotic ability of relaxin-2 in normal human atrial cardiac fibroblasts (NHCF-A). Peripheral vein relaxin-2 plasma levels were higher than LA relaxin-2 plasma levels in men while, in women, peripheral vein relaxin-2 levels were increased compared to men. AF patients with higher levels of relaxin-2 exhibited a reduction in H₂O₂ plasma levels and in mRNA levels of alpha-defensin 3 (DEFA3) and IL-6 in leucocytes from LA plasma. Relaxin-2-in-vitro treatment inhibited NHCF-A migration and decreased mRNA and protein levels of the pro-fibrotic molecule transforming growth factor-β1 (TGF-β1). Our results support an association between relaxin-2 and molecules involved in fibrosis, inflammation and oxidative stress in AF patients, and reinforce an anti-fibrotic protective role of this hormone in NHCF-A; strengthening the relevance of relaxin-2 in AF physiopathology, diagnosis and treatment.

Neutrophil-to-Lymphocyte Ratio and Outcomes in Patients Admitted for Acute Heart Failure (As Seen in the BLAST-AHF, Pre-RELAX-AHF, and RELAX-AHF Studies)

Previous studies have suggested that the neutrophil-to-lymphocyte ratio (NLR) is a novel yet readily evaluable inflammatory biomarker that may be useful for determining cardiovascular prognosis during acute episodes. The study investigated the role of NLR in predicting cardiovascular (CV) outcomes in patients with acute heart failure (HF). Individual patient data from the BLAST-AHF (phase 2b study of the biased ligand of the angiotensin 2 type 1 receptor, TRV027), Pre-RELAX-AHF (phase 2b study of recombinant human relaxin-2, serelaxin), and RELAX-AHF (phase 3 study of serelaxin) randomized, placebo-controlled studies for patients with acute HF were pooled for analysis. Dyspnea visual analog scale area under the curve through day 5, worsening HF through day 5, 30-day all-cause mortality, 60-day HF/renal failure rehospitalizations or CV death, 180-day all-cause mortality, and 180-day CV death were assessed. There were several differences in the baseline characteristics of the patients divided by NLR tertile, with patients in the higher NLR having worse clinical characteristics. NLR was an independent predictor of 30-day all-cause mortality (adjusted hazard ratio [HR] per log₂ NLR increment: 1.66 [1.22 to 2.25], p = 0.001), 60-day HF/renal failure rehospitalizations or CV death: 1.33 [1.12 to 1.57], p = 0.001), 180-day all-cause mortality (adjusted HR 1.27 [1.08 to 1.50], p = 0.003), and 180-day CV death (adjusted HR 1.24 [1.04 to 1.49], p = 0.018). NLR, a readily available inflammatory biomarker, was associated with independent risk for short- and long-term adverse outcomes in acute HF, surpassing traditional markers, such as natriuretic peptides.

Molecular Insights in Atrial Fibrillation Pathogenesis and Therapeutics: A Narrative Review

The prevalence of atrial fibrillation (AF) is bound to increase globally in the following years, affecting the quality of life of millions of people, increasing mortality and morbidity, and beleaguering health care systems. Increasingly effective therapeutic options against AF are the constantly evolving electroanatomic substrate mapping systems of the left atrium (LA) and ablation catheter technologies. Yet, a prerequisite for better long-term success rates is the understanding of AF pathogenesis and maintenance. LA electrical and anatomical remodeling remains in the epicenter of current research for novel diagnostic and treatment modalities. On a molecular level, electrical remodeling lies on impaired calcium handling, enhanced inwardly rectifying potassium currents, and gap junction perturbations. In addition, a wide array of profibrotic stimuli activates fibroblast to an increased extracellular matrix turnover via various intermediaries. Concomitant dysregulation of the autonomic nervous system and the humoral function of increased epicardial adipose tissue (EAT) are established mediators in the pathophysiology of AF. Local atrial lymphomononuclear cells infiltrate and increased inflammasome activity accelerate and perpetuate arrhythmia substrate. Finally, impaired intracellular protein metabolism, excessive oxidative stress, and mitochondrial dysfunction deplete atrial cardiomyocyte ATP and promote arrhythmogenesis. These overlapping cellular and molecular alterations hinder us from distinguishing the cause from the effect in AF pathogenesis. Yet, a plethora of therapeutic modalities target these molecular perturbations and hold promise in combating the AF burden. Namely, atrial selective ion channel inhibitors, AF gene therapy, anti-fibrotic agents, AF drug repurposing, immunomodulators, and indirect cardiac neuromodulation are discussed here.

Does rhythm matter in acute heart failure? An insight from the British Society for Heart Failure National Audit

Background

Atrial fibrillation (AF) is the most common sustained arrhythmia in patients with acute heart failure (AHF). The presence of AF is associated with adverse prognosis in patients with chronic heart failure (CHF) but little is known about its impact in AHF.

Methods

Data were collected between April 2007 and March 2013 across 185 (> 95%) hospitals in England and Wales from patients with a primary death or a discharge diagnosis of AHF. We investigated the association between the presence of AF and all-cause mortality during the index hospital admission, at 30 days and 1 year post-discharge.

Results

Of 96,593 patients admitted with AHF, 44,642 (46%) were in sinus rhythm (SR) and 51,951 (54%) in AF. Patients with AF were older (mean age 79.8 (79.7–80) versus 74.7 (74.5–74.7) years; p < 0.001), than those in SR. In a multivariable analysis, AF was independently associated with mortality at all time points, in hospital (HR 1.15, 95% CI 1.09–1.21, p < 0.0001), 30 days (HR 1.13, 95% CI 1.08–1.19, p < 0.0001), and 1 year (HR 1.09, 95% CI 1.05–1.12, p < 0.0001). In subgroup analyses, AF was independently associated with worse 30-day outcome irrespective of sex, ventricular phenotype and in all age groups except in those aged between 55 and 74 years.

Conclusion

AF is independently associated with adverse prognosis in AHF during admission and up to 1 year post-discharge. As the clinical burden of concomitant AF and AHF increases, further refinement in the detection, treatment and prevention of AF-related complications may have a role in improving patient outcomes.

Electronic supplementary material

The online version of this article (10.1007/s00392-019-01463-5) contains supplementary material, which is available to authorized users.

[Update on heart failure]

Heart failure is one of the leading diseases in internal medicine worldwide. Because of the increase in population aging, the incidence and prevalence of heart insufficiency is rising annually and is now the most frequent individual diagnosis among hospitalized patients in Germany. The mortality rate has recently been reduced, since new pharmacological options, especially the inhibition of neprilysin, have been developed; however, heart failure is still associated with a high mortality and morbidity rate. Thus, guideline-conform treatment is of crucial importance. This review highlights and summarizes the current scientific knowledge on heart failure from 2017 and 2018 based on the guidelines of the European Society of Cardiology. New aspects about heart failure with middle grade limitations of ejection fraction are firstly presented. Subsequently, innovative diagnostic and therapeutic strategies, new pharmacological developments and handling of frequent comorbidities in patients with heart failure are discussed.

Heart Disease and Relaxin: New Actions for an Old Hormone

The hormone relaxin has long been recognized for its involvement in maternal adaptation during pregnancy. However, discoveries during the past two decades on the mechanism of action of relaxin, its family of receptors, and newly described roles in attenuating ischemia/reperfusion (I/R) injury, inflammation, and arrhythmias have prompted vast interest in exploring its therapeutic potential in cardiovascular disease. These observations inspired recently concluded clinical trials in patients with acute heart failure. This review discusses our current understanding of the protective signaling pathways elicited by relaxin in the heart, and highlights important new breakthroughs about relaxin signaling that may pave the way to more carefully designed future trials.

Combined use of lung ultrasound, B-type natriuretic peptide, and echocardiography for outcome prediction in patients with acute HFrEF and HFpEF

BACKGROUND

Lung ultrasound (LUS) can be used to assess pulmonary congestion by imaging B-lines ('comets') for patients with acute heart failure (AHF).

OBJECTIVES

Investigate relationship of B-lines, plasma concentrations of B-type natriuretic peptide (BNP), and echocardiographic left ventricular (LV) function measured at admission and discharge and their relationship to prognosis for AHF with preserved (HFpEF) or reduced (HFrEF) LV ejection fraction.

METHODS

Patients with AHF had the above tests done at admission and discharge. The primary outcome was re-hospitalization for heart failure or death at 6 months.

RESULTS

Of 162 patients enrolled, 95 had HFrEF and 67 had HFpEF, median age was 80 [77-85] years, and 85 (52%) were women. The number of B-lines at admission (median 31 [27-36]) correlated with respiratory rate (r = 0.75; p < 0.001), BNP (r = 0.43; p < 0.001), clinical congestion score (r = 0.25; p = 0.001), and systolic pulmonary artery pressure (r = 0.42; p < 0.001). At discharge, B-lines were also correlated with BNP (r = 0.69; p < 0.001) and congestion score (r = 0.57; p < 0.001). B-line count at discharge predicted outcome (AUC 0.83 [0.77-0.90]; univariate HR 1.12 [1.09-1.16]; p < 0.001; multivariable HR 1.16 [1.11-1.21]; p < 0.001). Results were similar for HFpEF and HFrEF.

CONCLUSIONS

LUS appears a useful method to assess severity and monitor the resolution of lung congestion. At hospital admission, B-lines are strongly related to respiratory rate, which may be a key component of the sensation of dyspnea. Measurement of lung congestion at discharge provides prognostic information for patients with either HFpEF or HFrEF.

Early treatment with tolvaptan improves diuretic response in acute heart failure with renal dysfunction

BACKGROUND

Poor response to diuretics is associated with worse prognosis in patients with acute heart failure (AHF). We hypothesized that treatment with tolvaptan improves diuretic response in patients with AHF.

METHODS

We performed a secondary analysis of the AQUAMARINE open-label randomized study in which a total of 217 AHF patients with renal impairment (eGFR < 60 mL/min/1.73 m²) were randomized to either tolvaptan or conventional treatment. We evaluated diuretic response to 40 mg furosemide or its equivalent based on two different parameters: change in body weight and net fluid loss within 48 h.

RESULTS

The mean time from patient presentation to randomization was 2.9 h. Patients with a better diuretic response showed greater relief of dyspnea and less worsening of renal function. Tolvaptan patients showed a significantly better diuretic response measured by diuretic response based both body weight [-1.16 (IQR -3.00 to -0.57) kg/40 mg vs. -0.51 (IQR -1.13 to -0.20) kg/40 mg; P < 0.001] and net fluid loss [2125.0 (IQR 1370.0-3856.3) mL/40 mg vs. 1296.3 (IQR 725.2-1726.5) mL/40 mg; P < 0.001]. Higher diastolic blood pressure and use of tolvaptan were independent predictors of a better diuretic response.

CONCLUSIONS

Better diuretic response was associated with greater dyspnea relief and less WRF. Early treatment with tolvaptan significantly improved diuretic response in AHF patients with renal dysfunction.