Epidemiology of heart failure with preserved ejection fraction

Pulmonary vascular disease in the setting of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is defined as clinical features of heart failure, ideally with biomarker evidence such as elevated plasma natriuretic peptide levels, in the setting of an ejection fraction (EF) greater than 50% and imaging evidence of diastolic left ventricular dysfunction [1,2]. In the absence of cardiac imaging or invasive hemodynamics, this is a clinical syndrome that is often indistinguishable from heart failure with reduced ejection fraction (HFrEF). HFpEF and HFrEF present with a cadre of comparable signs and symptoms including jugular venous distention, pulmonary rales on auscultation, breathlessness, orthopnea, exercise intolerance, exertional dyspnea, fatigue and peripheral edema. HFpEF accounts for at least half of all diagnoses of heart failure [1,2]. Pulmonary hypertension (PH) is a common complication of HFpEF that is linked to worse disease morbidity and mortality. In fact, mortality has been linked to increases in the intrinsic pulmonary vascular resistance in the setting of increased left ventricular end diastolic pressure, characterized hemodynamically by rises in the transpulmonary pressure gradient, pulmonary vascular resistance or diastolic pressure gradient. Despite being the most common form of PH, there are no approved therapies for the treatment of PH secondary to HFpEF. This review will summarize the hemodynamic classifications of PH in the setting of HFpEF, mechanisms of disease, the potential contribution of pulmonary vascular disease to poor outcomes in patients with HFpEF, and new approaches to therapy.

A mouse model for the most common form of heart failure

A mouse model that replicates the clinical features of the most common form of heart failure opens a window on the mechanisms underlying this disease, and could help scientists to explore future therapies.

Nitrosative stress drives heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is a common syndrome with high morbidity and mortality for which there are no evidence-based therapies. Here we report that concomitant metabolic and hypertensive stress in mice-elicited by a combination of high-fat diet and inhibition of constitutive nitric oxide synthase using Nω-nitro-L-arginine methyl ester (L-NAME)-recapitulates the numerous systemic and cardiovascular features of HFpEF in humans. Expression of one of the unfolded protein response effectors, the spliced form of X-box-binding protein 1 (XBP1s), was reduced in the myocardium of our rodent model and in humans with HFpEF. Mechanistically, the decrease in XBP1s resulted from increased activity of inducible nitric oxide synthase (iNOS) and S-nitrosylation of the endonuclease inositol-requiring protein 1α (IRE1α), culminating in defective XBP1 splicing. Pharmacological or genetic suppression of iNOS, or cardiomyocyte-restricted overexpression of XBP1s, each ameliorated the HFpEF phenotype. We report that iNOS-driven dysregulation of the IRE1α-XBP1 pathway is a crucial mechanism of cardiomyocyte dysfunction in HFpEF.

Relationships between maintenance of sinus rhythm and clinical outcomes in patients with heart failure with preserved ejection fraction and atrial fibrillation

BACKGROUND

Although atrial fibrillation (AF) is associated with exacerbation of heart failure with preserved ejection fraction (HFpEF), the relationships between maintenance of sinus rhythm (SR) and clinical outcomes in HFpEF is unknown. We investigated whether maintenance of SR was associated with better prognosis compared with rate control in patients with concomitant HFpEF and AF.

METHODS

We conducted a retrospective, observational study of 283 patients with HFpEF and AF. Of these, 107 patients achieved maintenance of SR by catheter ablation and/or antiarrhythmic drugs (rhythm control) and 176 were treated with rate control. The propensity score (PS) for each patient in both treatment groups was estimated, resulting in selectively matched subgroups of 79 patients each. All-cause death and a composite of cardiovascular death or hospitalization for heart failure (HF) were analyzed.

RESULTS

During a median follow-up period of 24 months, all-cause mortality was comparable between groups; however, maintenance of SR was significantly associated with a lower incidence of the composite endpoint [adjusted hazard ratio (HR), 0.30; 95% confidence interval, 0.18-0.98; p=0.04] in the PS-matched cohort. The PS-adjusted multivariable analysis based on 283 pre-matched patients also revealed that rhythm control was associated with a lower rate of the composite endpoint (adjusted HR, 0.27; 95% CI, 0.12-0.61; p=0.002). Subgroup analyses suggested that rhythm control was consistently related to the composite endpoint across a wide spectrum of HFpEF patients.

CONCLUSIONS

Maintenance of SR was associated with a lower risk of composite of cardiovascular death or hospitalization for HF in patients with HFpEF and AF. A randomized trial is necessary to confirm this result.

Think-aloud study about the diagnosis of chronic heart failure in Belgian general practice

OBJECTIVES

Diagnosing chronic heart failure (CHF) in general practice is challenging. Our aim was to investigate how general practitioners (GPs) diagnose CHF in real-world patients.

DESIGN

Think-aloud study.

METHODS

Fourteen GPs were asked to reason about four real-world CHF cases from their own practices. The cases were selected through a clinical audit. This was followed by an interview to get a deeper insight in their reasoning. The Qualitative Analysis Guide of Leuven was used as a guide in data analysis.

RESULTS

We developed a conceptual diagnostic model based on three important reasoning steps. First, GPs assessed the likelihood of CHF based on the presence or absence of HF signs and symptoms. However, this approach had serious limitations since GPs experienced many barriers in their clinical assessment, especially in comorbid elderly. Second, if CHF was considered based on step 1, the main influencing factor to take further diagnostic steps was the GPs' perception of the added value of a validated CHF diagnosis in that specific case. Third, the choice and implications of these further diagnostic steps (N-terminal pro B-type natriuretic peptide, ECG and/or cardiac ultrasound) were influenced by the GPs' knowledge about these tests and the quality of the cardiologists' reports.

CONCLUSION

This think-aloud study identified the factors that influenced the diagnostic reasoning about CHF in general practice. As a consequence, targets to improve this diagnostic reasoning were withheld: a paradigm shift towards an earlier and more comprehensive risk assessment with, among others, access to natriuretic peptide testing and convincing GPs of the added value of a validated HF diagnosis.

The role of arterial hypertension in development heart failure with preserved ejection fraction: just a risk factor or something more?

Heart failure with preserved ejection fraction (HFpEF) is an entity that still raises many questions. The agreement about definition, pathophysiology, and therapeutic approach is still missing. Arterial hypertension is present in majority of patients with HFpEF, and it is still not clear if it represent a risk factor or "sine qua non" condition for HFpEF development. The underlying mechanisms of hypertension and HFpEF involve the same biohumoral systems: renin-angiotensin-aldosterone, sympathetic nervous system, and oxidative stress. However, not all hypertensive patients have HFpEF. The predisposition of some hypertensive patients to develop HFpEF needs to be resolved. Large randomized controlled trials did not prove the usefulness of renin-angiotensin-aldosterone inhibitors, diuretics, calcium channel blockers, and beta-blockers in HFpEF patients. The majority of studies did not succeed to demonstrate the reduction of cardiovascular and all-cause mortality in HFpEF individuals. One of the major limitations in these investigations was the inconsistency of HFpEF definition, which mainly refers to left ventricular ejection fraction (LVEF) cut-off that ranged from 40 to 50% in different studies. This review article provides the available data about pathophysiology and mechanisms that connect hypertension and HFpEF, investigations and therapy used in both conditions.

Beyond pharmacological treatment: an insight into therapies that target specific aspects of heart failure pathophysiology

Heart failure is a common syndrome associated with substantial morbidity and mortality. The management of symptoms and the strategies for improving prognosis have largely been based on pharmacological treatments. The pathophysiology of heart failure is complex because of the multiple causes responsible for this syndrome. This Series paper presents some examples of advances in heart failure management, in which the treatment specifically targets the underlying pathophysiological mechanisms responsible for the symptoms. These treatments include treatment of electromechanical dyssynchrony and dysrhythmia by cardiac resynchronisation and implantable cardioverter-defibrillators; neurohumoral modification by baroreflex and vagal stimulation; prevention of adverse cardiac remodelling by interatrial shunts; and finally targeting the myocardium directly by cell therapy in an attempt to regenerate new myocardial cells.

Sex-Specific Physiology and Cardiovascular Disease

Sex differences in cardiovascular diseases can be classified as those which are specific to one sex and those that differ in incidence, prevalence, etiology, symptomatology, response to treatment, morbidity, and mortality in one sex compared to the other. All sex differences in cardiovascular conditions have their basis in the combined expression of genetic and hormonal differences between women and men. This chapter addresses how understanding basic mechanisms of hormone responses, imaging diagnostics, and integration of genomics and proteomics has advanced diagnosis and improved outcomes for cardiovascular conditions, apart from those related to pregnancy that are more prevalent in women. These conditions include obstructive coronary artery disease, coronary microvascular dysfunction, spontaneous coronary artery dissection, diseases of the cardiac muscle including heart failure and takotsubo cardiomyopathy, and conditions related to neurovascular dysregulation including hot flashes and night sweats associated with menopause and effects of exogenous hormones on vascular function. Improvement in technologies allowing for noninvasive assessment of neuronally mediated vascular reactivity will further improve our understanding of the basic etiology of the neurovascular disorders. Consideration of sex, hormonal status, and pregnancy history in diagnosis and treatment protocols will improve prevention and outcomes of cardiovascular disease in women as they age.

Macrophages in Heart Failure with Reduced versus Preserved Ejection Fraction

There is a growing number of individuals living with heart failure (HF) with reduced ejection fraction (HFrEF) or preserved ejection fraction (HFpEF). Long-term prognosis remains poor in both cases, especially in HFpEF, which is rising in incidence and lacks effective therapeutics. In both HFrEF and HFpEF, there is evidence that elevated inflammatory biomarkers, implicating innate immune cells such as macrophages, are associated with worsened clinical outcomes. Macrophage subsets are active in both inflammatory and reparative processes, yet our understanding of the causative roles for these cells in HF development and progression is incomplete. Here, we discuss recent findings interrogating the role of macrophages in inflammation and its resolution in the context of HF, with a specific focus on HFrEF versus HFpEF.

Exercise-based cardiac rehabilitation for adults with heart failure

BACKGROUND

Chronic heart failure (HF) is a growing global health challenge. People with HF experience substantial burden that includes low exercise tolerance, poor health-related quality of life (HRQoL), increased risk of mortality and hospital admission, and high healthcare costs. The previous (2014) Cochrane systematic review reported that exercise-based cardiac rehabilitation (CR) compared to no exercise control shows improvement in HRQoL and hospital admission among people with HF, as well as possible reduction in mortality over the longer term, and that these reductions appear to be consistent across patient and programme characteristics. Limitations noted by the authors of this previous Cochrane Review include the following: (1) most trials were undertaken in patients with HF with reduced (< 45%) ejection fraction (HFrEF), and women, older people, and those with preserved (≥ 45%) ejection fraction HF (HFpEF) were under-represented; and (2) most trials were undertaken in the hospital/centre-based setting.

OBJECTIVES

To determine the effects of exercise-based cardiac rehabilitation on mortality, hospital admission, and health-related quality of life of people with heart failure.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and three other databases on 29 January 2018. We also checked the bibliographies of systematic reviews and two trial registers.

SELECTION CRITERIA

We included randomised controlled trials that compared exercise-based CR interventions with six months' or longer follow-up versus a no exercise control that could include usual medical care. The study population comprised adults (> 18 years) with evidence of HF - either HFrEF or HFpEF.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all identified references and rejected those that were clearly ineligible for inclusion in the review. We obtained full papers of potentially relevant trials. Two review authors independently extracted data from the included trials, assessed their risk of bias, and performed GRADE analyses.

MAIN RESULTS

We included 44 trials (5783 participants with HF) with a median of six months' follow-up. For this latest update, we identified 11 new trials (N = 1040), in addition to the previously identified 33 trials. Although the evidence base includes predominantly patients with HFrEF with New York Heart Association classes II and III receiving centre-based exercise-based CR programmes, a growing body of studies include patients with HFpEF and are undertaken in a home-based setting. All included studies included a no formal exercise training intervention comparator. However, a wide range of comparators were seen across studies that included active intervention (i.e. education, psychological intervention) or usual medical care alone. The overall risk of bias of included trials was low or unclear, and we downgraded results using the GRADE tool for all but one outcome.Cardiac rehabilitation may make little or no difference in all-cause mortality over the short term (≤ one year of follow-up) (27 trials, 28 comparisons (2596 participants): intervention 67/1302 (5.1%) vs control 75/1294 (5.8%); risk ratio (RR) 0.89, 95% confidence interval (CI) 0.66 to 1.21; low-quality GRADE evidence) but may improve all-cause mortality in the long term (> 12 months follow up) (6 trials/comparisons (2845 participants): intervention 244/1418 (17.2%) vs control 280/1427 (19.6%) events): RR 0.88, 95% CI 0.75 to 1.02; high-quality evidence). Researchers provided no data on deaths due to HF. CR probably reduces overall hospital admissions in the short term (up to one year of follow-up) (21 trials, 21 comparisons (2182 participants): (intervention 180/1093 (16.5%) vs control 258/1089 (23.7%); RR 0.70, 95% CI 0.60 to 0.83; moderate-quality evidence, number needed to treat: 14) and may reduce HF-specific hospitalisation (14 trials, 15 comparisons (1114 participants): (intervention 40/562 (7.1%) vs control 61/552 (11.1%) RR 0.59, 95% CI 0.42 to 0.84; low-quality evidence, number needed to treat: 25). After CR, a clinically important improvement in short-term disease-specific health-related quality of life may be evident (Minnesota Living With Heart Failure questionnaire - 17 trials, 18 comparisons (1995 participants): mean difference (MD) -7.11 points, 95% CI -10.49 to -3.73; low-quality evidence). Pooling across all studies, regardless of the HRQoL measure used, shows there may be clinically important improvement with exercise (26 trials, 29 comparisons (3833 participants); standardised mean difference (SMD) -0.60, 95% CI -0.82 to -0.39; I² = 87%; Chi² = 215.03; low-quality evidence). ExCR effects appeared to be consistent different models of ExCR delivery: centre vs. home-based, exercise dose, exercise only vs. comprehensive programmes, and aerobic training alone vs aerobic plus resistance programmes.

AUTHORS' CONCLUSIONS

This updated Cochrane Review provides additional randomised evidence (11 trials) to support the conclusions of the previous version (2014) of this Cochane Review. Compared to no exercise control, CR appears to have no impact on mortality in the short term (< 12 months' follow-up). Low- to moderate-quality evidence shows that CR probably reduces the risk of all-cause hospital admissions and may reduce HF-specific hospital admissions in the short term (up to 12 months). CR may confer a clinically important improvement in health-related quality of life, although we remain uncertain about this because the evidence is of low quality. Future ExCR trials need to continue to consider the recruitment of traditionally less represented HF patient groups including older, female, and HFpEF patients, and alternative CR delivery settings including home- and using technology-based programmes.

Evolving Landscape of Clinical Trials in Heart Failure: Patient Populations, Endpoint Selection, and Regions of Enrollment

PURPOSE OF REVIEW

Clinical trial design and execution are evolving as increasingly important considerations with respect to the success of heart failure trials. The current review highlights temporal trends in characteristics of heart failure clinical trials.

RECENT FINDINGS

Recent trials in heart failure have required longer recruitment phases, displayed inefficient enrollment rates, increased use of composite and nonfatal endpoints, undergone rapid globalization, and gradually increased focus on heart failure with preserved ejection fraction. Understanding patterns and trends in clinical trial design and execution may inform future planning and conduct of trials of heart failure therapeutics.

Female Heart Health: Is GPER the Missing Link?

The G Protein-Coupled Estrogen Receptor (GPER) is a novel membrane-bound receptor that mediates non-genomic actions of the primary female sex hormone 17β-estradiol. Studies over the past two decades have elucidated the beneficial actions of this receptor in a number of cardiometabolic diseases. This review will focus specifically on the cardiac actions of GPER, since this receptor is expressed in cardiomyocytes as well as other cells within the heart and most likely contributes to estrogen-induced cardioprotection. Studies outlining the impact of GPER on diastolic function, mitochondrial function, left ventricular stiffness, calcium dynamics, cardiac inflammation, and aortic distensibility are discussed. In addition, recent data using genetic mouse models with global or cardiomyocyte-specific GPER gene deletion are highlighted. Since estrogen loss due to menopause in combination with chronological aging contributes to unique aspects of cardiac dysfunction in women, this receptor may provide novel therapeutic effects. While clinical studies are still required to fully understand the potential for pharmacological targeting of this receptor in postmenopausal women, this review will summarize the evidence gathered thus far on its likely beneficial effects.

The E/e' ratio difference between subjects with type 2 diabetes and controls. A meta-analysis of clinical studies

Type 2 diabetes is associated with an increased risk of heart failure. Left ventricular diastolic dysfunction and type 2 diabetes are frequently associated. Using echocardiography, we know that tissue Doppler imaging E/e’ ratio is a reliable predictor of left ventricular filling pressure. We performed a systematic review and meta-analysis to investigate the averaged E/e’ ratio value in patients with type 2 diabetes compared to non-diabetic controls. In the analysis we included cross-sectional studies providing the averaged E/e’ ratio. Subgroup/sensitivity analyses were conducted according to variables known to influence E/e’ ratio measurements. The analysis included 15 cross sectional studies with 877 type 2 diabetes patients and 1193 controls. The weighted mean difference showed higher values in diabetes (WMD 2.02; 95% CI 1.35, 2.70; p<0.001). The result was consistent in the subgroup/sensitivity analyses. Visual inspection of the funnel plot did not identify substantial asymmetry and the Egger test for funnel plot asymmetry showed a p value of 0.36. In conclusion, our assessment suggests that averaged E/e’ ratio is consistently increased in patients with type 2 diabetes compared to non-diabetic controls in the absence of cardiovascular diseases and complicated hypertension. This alteration may be a precocious diastolic alteration in the diabetic cardiomyopathy.

Heart diseases and echocardiography in rural Tanzania: Occurrence, characteristics, and etiologies of underappreciated cardiac pathologies

BACKGROUND

Little is known about heart diseases and their treatment in rural sub-Saharan Africa. This study aimed to describe the occurrence, characteristics, and etiologies of heart diseases, and the medication taken before and prescribed after echocardiography in a rural referral Hospital in Tanzania.

METHODS

This prospective descriptive cohort study included all adults and children referred for echocardiography. Clinical and echocardiographic data were collated for analysis.

RESULTS

From December 2015 to October 2017, a total of 1'243 echocardiograms were performed. A total of 815 adults and 59 children ≤15 years had abnormal echocardiographic findings; in adults 537/815 (66%) had hypertension, with 230/537(43%) on antihypertensive drugs, and 506/815 (62%) were not on regular cardiac medication; 346/815 (42%) had severe eccentric or concentric left ventricular hypertrophy, and 182/815 (22%) had severe systolic heart failure. Only 44% demonstrated normal left ventricular systolic function. The most frequent heart diseases were hypertensive heart disease (41%), valvular heart disease (18%), coronary heart disease (18%), peripartum cardiomyopathy (7%), and other non-hypertensive dilated cardiomyopathies (6%) in adults, and congenital heart disease (34%) in children. Following echocardiography, 802/815 (98%) adults and 40/59 (68%) children had an indication for cardiac medication, 70/815 (9%) and 2/59 (3%) for oral anticoagulation, and 35/815 (4%) and 23/59 (39%) for cardiac surgery, respectively.

CONCLUSION

Hypertension is the leading etiology of heart diseases in rural Tanzania. Most patients present with advanced stages of heart disease, and the majority are not treated before echocardiography. There is an urgent need for increased awareness, expertise and infrastructure to detect and treat hypertension and heart failure in rural Africa.

Mechanisms of Sex Disparities in Cardiovascular Function and Remodeling

Epidemiological studies demonstrate disparities between men and women in cardiovascular disease prevalence, clinical symptoms, treatments, and outcomes. Enrollment of women in clinical trials is lower than men, and experimental studies investigating molecular mechanisms and efficacy of certain therapeutics in cardiovascular disease have been primarily conducted in male animals. These practices bias data interpretation and limit the implication of research findings in female clinical populations. This review will focus on the biological origins of sex differences in cardiovascular physiology, health, and disease, with an emphasis on the sex hormones, estrogen and testosterone. First, we will briefly discuss epidemiological evidence of sex disparities in cardiovascular disease prevalence and clinical manifestation. Second, we will describe studies suggesting sexual dimorphism in normal cardiovascular function from fetal life to older age. Third, we will summarize and critically discuss the current literature regarding the molecular mechanisms underlying the effects of estrogens and androgens on cardiac and vascular physiology and the contribution of these hormones to sex differences in cardiovascular disease. Fourth, we will present cardiovascular disease risk factors that are positively associated with the female sex, and thus, contributing to increased cardiovascular risk in women. We conclude that inclusion of both men and women in the investigation of the role of estrogens and androgens in cardiovascular physiology will advance our understanding of the mechanisms underlying sex differences in cardiovascular disease. In addition, investigating the role of sex-specific factors in the development of cardiovascular disease will reduce sex and gender disparities in the treatment and diagnosis of cardiovascular disease. © 2019 American Physiological Society. Compr Physiol 9:375-411, 2019.

The metabolic model of heart failure: the role of sodium glucose co-transporter-2 (SGLT-2) inhibition

Heart failure (HF) is one of the leading causes of hospital readmissions and health care expenditures. With a vast degree of advancements in the clinical approach and diagnosis, its management protocol is limited in terms of enhancing quality of life and prognosis. Type 2 diabetes mellitus (T2DM) is considered as one of the commonly associated comorbid conditions in the HF population. The understanding of the molecular and metabolic models of HF has led to the utilization of therapeutic goals of T2DM in improving HF-related complications. In the recent era, SGLT-2 inhibitors have shown success in decreasing cardiovascular mortality in the T2DM population. This article will help the reviewer to comprehend the pathophysiology of HF and the potential role of SGLT-2 inhibitors in the management algorithm of HF and its associated risk factors in T2DM.

The prevalence of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction in men and women with type 2 diabetes: A systematic review and meta-analysis

OBJECTIVE

Type 2 diabetes is a risk factor for the development of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction. Our aim was to provide a summary estimate of the prevalence of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction in type 2 diabetes patients and to investigate sex disparities.

METHODS AND RESULTS

A systematic search of the databases Medline and Embase was conducted for studies reporting the prevalence of left ventricular diastolic dysfunction or heart failure with preserved ejection fraction among type 2 diabetes patients. Studies were only included if echocardiography was performed. Prevalence estimates were pooled using random-effects meta-analysis. A total of 28 studies were included. Data on the prevalence of left ventricular diastolic dysfunction were available in 27 studies. The pooled prevalence for left ventricular diastolic dysfunction in the hospital population (2959 type 2 diabetes participants) and in the general population (2813 type 2 diabetes participants) was 48% [95% confidence interval: 38%-59%] and 35% (95% confidence interval: 24%-46%), respectively. Heterogeneity was high in both populations, with estimates ranging from 19% to 81% in the hospital population and from 23% to 54% in the general population. For women and men, the pooled prevalence estimates of left ventricular diastolic dysfunction were 47% (95% confidence interval: 37%-58%) and 46% (95% confidence interval: 37%-55%), respectively. Only two studies presented the prevalence of heart failure with preserved ejection fraction; 8% (95% confidence interval: 5%-14%) in a hospital population and 25% (95% confidence interval: 21%-28%) in the general population [18% in men (mean age: 73.8; standard deviation: 8.6) and 28% in women (mean age: 74.9; standard deviation: 6.9)].

CONCLUSION

The prevalence of left ventricular diastolic dysfunction among type 2 diabetes patients is similarly high in men and women, while heart failure with preserved ejection fraction seems to be more common in women than men, at least in community people with type 2 diabetes.

Association between diastolic cardiac dysfunction and nonalcoholic fatty liver disease: A systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Recent studies have suggested an association between nonalcoholic fatty liver disease (NAFLD) and diastolic cardiac dysfunction, although the results were inconsistent. This study was conducted to investigate this possible association.

METHODS

A comprehensive literature review was conducted utilizing the MEDLINE and Embase databases from inception through May 2018 to identify all cross-sectional studies that compared the prevalence of diastolic cardiac dysfunction among patients with NAFLD to individuals without NAFLD. Effect estimates from each study were extracted and combined using the random-effect, generic inverse variance method of DerSimonian and Laird.

RESULTS

A total of 12 studies with 280,645 participants fulfilled the eligibility criteria and were included in the meta-analysis. There was a significant association between NAFLD and diastolic cardiac dysfunction with a pooled odds ratio (OR) of 2.02 (95% confidence interval (CI), 1.47-2.79; I² 89%). Subgroup analysis based on the country of origin continued to demonstrate a significant association in subgroups of both Western and Eastern countries with pooled ORs of 1.76 (95% CI, 1.14-2.72; I² 85%) and 2.59 (95% CI, 1.42-4.69; I² 87%), respectively. Limitations included high between-study heterogeneity, lack of unified definition of diastolic dysfunction and presence of publication bias.

CONCLUSIONS

A significant association between diastolic cardiac dysfunction and NAFLD was observed in this meta-analysis. This observation could suggest the need for careful cardiovascular surveillance among patients with NAFLD.

Primary and Secondary Diastolic Dysfunction in Heart Failure With Preserved Ejection Fraction

Approximately 50% of patients with symptoms and signs of heart failure have a left ventricular ejection fraction (LVEF) ≥50% and are often simply referred to as 'heart failure with preserved EF', 'HFpEF'. Many of such patients have HF secondary to specific cardiac conditions (i.e., valvular or pericardial disease) in which the symptoms and signs occur despite the LVEF being preserved due to diastolic dysfunction secondary to the underlying disease (secondary HFpEF), differently from those HFpEF patients in which the impaired LV filling is due to a primary diastolic dysfunction (primary HFpEF). When primary HFpEF patients are properly diagnosed, they appear to have a milder form of HF with a lower cardiovascular mortality compared with HFrEF and secondary HFpEF population, but a risk of HF hospitalization that is significantly higher than patients with similar cardiovascular risk factors but without the diagnosis of HFpEF. We herein review the diagnostic approach to HFpEF and present a differential diagnosis of HFpEF in a primary and secondary form.

The 3A3B score: The simple risk score for heart failure with preserved ejection fraction - A report from the CHART-2 Study

BACKGROUND

Few simple risk models, without echocardiography have been developed for patients with heart failure (HF) and preserved left ventricular ejection fraction (LVEF) (HFpEF).

METHODS

To develop a risk score to predict all-cause death for HFpEF patients, we examined 1277 HF patients with LVEF ≥50% and BNP ≥100 pg/ml in the CHART-2 Study, a large-scale prospective cohort study for HF in Japan. We selected the optimal subset of covariates for the score with Cox proportional hazard models and random survival forests (RSF).

RESULTS

During the median 5.7-year follow-up, 576 deaths occurred. Cox models and RSF analyses consistently indicated age ≥75 years, albumin <3.7 g/dl, anemia, BMI <22 kg/m², BNP ≥300 pg/ml (or NT-proBNP ≥1400 pg/ml), and BUN ≥25 mg/dl, as the important 6 prognostic variables. Incorporating these 6 variables, we developed a scoring system (3A3B score, with 2 points given to age ≥75 years and 1 point to the others based on the hazard ratios. The discrimination ability of the risk score was excellent (c-index 0.708). Regarding model goodness-of-fit, the overall gradient in 5-year risk was well captured by the score. The predictive accuracy of the 3A3B score was confirmed in the external validation cohorts from the TOPCAT trial (N = 835, c-index 0.652) and the ASIAN-HF registry (N = 170, c-index 0.741).

CONCLUSIONS

We developed a simple risk score to predict long-term prognosis of HFpEF patients. The 3A3B score, comprising 6 commonly available parameters in daily practice, has potential utility in the risk stratification and management of HFpEF patients.

Post-systolic shortening: normal values and association with validated echocardiographic and invasive measures of cardiac function

Post-systolic shortening (PSS) does not contribute to the ejection of blood and may inhibit diastolic filling. We determined normal values of PSS in healthy subjects and investigated associations with echocardiographic and invasive measures of systolic and diastolic function. We prospectively analyzed participants from the general population (n = 620, mean age 47 ± 14 years) with no cardiovascular disease. Participants underwent echocardiography, including speckle tracking assessment of the post-systolic index (PSI), strain and time. We defined the PSI as: 100 × [(peak global longitudinal strain - peak systolic longitudinal strain)/(peak global longitudinal strain)]. We also included stable patients (n = 44) referred for left ventricle (LV) catheterization and echocardiography. Normal values: median PSI 2.0% (IQR 0.7, 4.8), post-systolic strain 0.4% (IQR 0.2, 0.8) and post-systolic time 22.6 ms (IQR 10.7, 40.8). Sex modified the relationship between PSI and age (P interaction = 0.037), such that PSI increased with age in women but not in men. PSI was associated with diastolic function (e', E/e' and E/A) (P < 0.05 for all), but not with LV ejection fraction (P = 0.08). PSI was associated with invasively measured LV pressure decline in early diastole, dP/dt min ([Formula: see text] = 0.12, P = 0.010), but not with LV pressure rise in early systole, dP/dt max ([Formula: see text]= - 0.05, P = 0.30). A PSI > 5% had 82% specificity and 99% sensitivity for identifying impaired LV systolic and/or diastolic function. Normal values of PSS are modified by sex. The PSI is associated with most validated echocardiographic and invasive measures of cardiac systolic and diastolic function.

Role of autophagy in inherited metabolic and endocrine myopathies

The prevalence of cardiometabolic disease has reached an exponential rate of rise over the last decades owing to high fat/high caloric diet intake and satiety life style. Although the presence of dyslipidemia, insulin resistance, hypertension and obesity mainly contributes to the increased incidence of cardiometabolic diseases, population-based, clinical and genetic studies have revealed a rather important role for inherited myopathies and endocrine disorders in the ever-rising metabolic anomalies. Inherited metabolic and endocrine diseases such as glycogen storage and lysosomal disorders have greatly contributed to the overall prevalence of cardiometabolic diseases. Recent evidence has demonstrated an essential role for proteotoxicity due to autophagy failure and/or dysregulation in the onset of inherited metabolic and endocrine disorders. Given the key role for autophagy in the degradation and removal of long-lived or injured proteins and organelles for the maintenance of cellular and organismal homeostasis, this mini-review will discuss the potential contribution of autophagy dysregulation in the pathogenesis of inherited myopathies and endocrine disorders, which greatly contribute to an overall rise in prevalence of cardiometabolic disorders. Molecular, clinical, and epidemiological aspects will be covered as well as the potential link between autophagy and metabolic anomalies thus target therapy may be engaged for these comorbidities.

Impact of an interatrial shunt device on survival and heart failure hospitalization in patients with preserved ejection fraction

Aims

Impaired left ventricular diastolic function leading to elevated left atrial pressures, particularly during exertion, is a key driver of symptoms and outcomes in heart failure with preserved ejection fraction (HFpEF). Insertion of an interatrial shunt device (IASD) to reduce left atrial pressure in HFpEF has been shown to be associated with short‐term haemodynamic and symptomatic benefit. We aimed to investigate the potential effects of IASD placement on HFpEF survival and heart failure hospitalization (HFH).

Methods and results

Heart failure with preserved ejection fraction patients participating in the Reduce Elevated Left Atrial Pressure in Patients with Heart Failure study (Corvia Medical) of an IASD were followed for a median duration of 739 days. The theoretical impact of IASD implantation on HFpEF mortality was investigated by comparing the observed survival of the study cohort with the survival predicted from baseline data using the Meta‐analysis Global Group in Chronic Heart Failure heart failure risk survival score. Baseline and post‐IASD implant parameters associated with HFH were also investigated. Based upon the individual baseline demographic and cardiovascular profile of the study cohort, the Meta‐analysis Global Group in Chronic Heart Failure score‐predicted mortality was 10.2/100 pt years. The observed mortality rate of the IASD‐treated cohort was 3.4/100 pt years, representing a 33% lower rate (P = 0.02). By Kaplan–Meier analysis, the observed survival in IASD patients was greater than predicted (P = 0.014). Baseline parameters were not predictive of future HFH events; however, poorer exercise tolerance and a higher workload‐corrected exercise pulmonary capillary wedge pressure at the 6 months post‐IASD study were associated with HFH.

Conclusions

The current study suggests IASD implantation may be associated with a reduction in mortality in HFpEF. Large‐scale ongoing randomized studies are required to confirm the potential benefit of this therapy.

Reverse electrical remodeling in rats with heart failure and preserved ejection fraction

Sudden death is the most common mode of exodus in patients with heart failure and preserved ejection fraction (HFpEF). Cardiosphere-derived cells (CDCs) reduce inflammation and fibrosis in a rat model of HFpEF, improving diastolic function and prolonging survival. We tested the hypothesis that CDCs decrease ventricular arrhythmias (VAs) and thereby possibly contribute to prolonged survival. Dahl salt-sensitive rats were fed a high-salt diet to induce HFpEF. Allogeneic rat CDCs (or phosphate-buffered saline as placebo) were injected in rats with echo-verified HFpEF. CDC-injected HFpEF rats were less prone to VA induction by programmed electrical stimulation. Action potential duration (APD) was shortened, and APD homogeneity was increased by CDC injection. Transient outward potassium current density was upregulated in cardiomyocytes from CDC rats relative to placebo, as were the underlying transcript (Kcnd3) and protein (Kv4.3) levels. Fibrosis was attenuated in CDC-treated hearts, and survival was increased. Sudden death risk also trended down, albeit nonsignificantly. CDC therapy decreased VA in HFpEF rats by shortening APD, improving APD homogeneity, and decreasing fibrosis. Unlike other stem/progenitor cells, which often exacerbate arrhythmias, CDCs reverse electrical remodeling and suppress arrhythmogenesis in HFpEF.

Characterization of a mouse model of obesity-related fibrotic cardiomyopathy that recapitulates features of human heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is caused, or exacerbated by, a wide range of extracardiac conditions. Diabetes, obesity, and metabolic dysfunction are associated with a unique HFpEF phenotype, characterized by inflammation, cardiac fibrosis, and microvascular dysfunction. Development of new therapies for HFpEF is hampered by the absence of reliable animal models. The leptin-resistant db/ db mouse has been extensively studied as a model of diabetes-associated cardiomyopathy; however, data on the functional and morphological alterations in db/ db hearts are conflicting. In the present study, we report a systematic characterization of the cardiac phenotype in db/ db mice, focusing on the time course of functional and histopathological alterations and on the identification of sex-specific cellular events. Although both male and female db/ db mice developed severe obesity, increased adiposity, and hyperglycemia, female mice had more impressive weight gain and exhibited a modest but significant increase in blood pressure. db/ db mice had hypertrophic ventricular remodeling and diastolic dysfunction with preserved ejection fraction; the increase in left ventricular mass was accentuated in female mice. Histological analysis showed that both male and female db/ db mice had cardiomyocyte hypertrophy and interstitial fibrosis, associated with marked thickening of the perimysial collagen, and expansion of the periarteriolar collagen network, in the absence of replacement fibrosis. In vivo and in vitro experiments showed that fibrotic changes in db/ db hearts were associated with increased collagen synthesis by cardiac fibroblasts, in the absence of periostin, α-smooth muscle actin, or fibroblast activation protein overexpression. Male db/ db mice exhibited microvascular rarefaction. In conclusion, the db/ db mouse model recapitulates functional and histological features of human HFpEF associated with metabolic dysfunction. Development of fibrosis in db/ db hearts, in the absence of myofibroblast conversion, suggests that metabolic dysfunction may activate an alternative profibrotic pathway associated with accentuated extracellular matrix protein synthesis. NEW & NOTEWORTHY We provide a systematic analysis of the sex-specific functional and structural myocardial alterations in db/ db mice. Obese diabetic C57BL6J db/ db mice exhibit diastolic dysfunction with preserved ejection fraction, associated with cardiomyocyte hypertrophy, interstitial/perivascular fibrosis, and microvascular rarefaction, thus recapitulating aspects of human obesity-related heart failure with preserved ejection fraction. Myocardial fibrosis in db/ db mice is associated with a matrix-producing fibroblast phenotype, in the absence of myofibroblast conversion, suggesting an alternative mechanism of activation.

Diastolic Dysfunction, an Underestimated New Challenge in Dialysis

Heart failure (HF) is very common in the general population and specifically in CKD patients due to higher prevalence of traditional and CKD-related risk factors. In particular, HF with preserved ejection fraction (HFpEF) can affect over 50% of dialysis patients. However, little is known about this entity in CKD. It has been inadequately recognized over time and few data exist regarding clinical profiles and outcomes in dialysis patients. The aim of this paper is to do a critical appraisal of the diagnosis, clinical impact, and management of HFpEF with a focus on new diagnostic criteria and its impact on dialysis.

Histones and heart failure in diabetes

Although heart failure is now accepted as being a major long-term complication of diabetes, many of the recent advances in our understanding of the pathobiology of diabetes complications have come about through the study of more traditional microvascular or macrovascular diseases. This has been the case, for example, in the evolving field of the epigenetics of diabetes complications and, in particular, the post-translational modification of histone proteins. However, histone modifications also occur in human heart failure and their perturbation also occurs in diabetic hearts. Here, we review the principal histone modifications and their enzymatic writers and erasers that have been studied to date; we discuss what is currently known about their roles in heart failure and in the diabetic heart; we draw on lessons learned from the studies of microvascular and macrovascular complications; and we speculate that therapeutically manipulating histone modifications may alter the natural history of heart failure in diabetes.

Risk factors for incident heart failure with preserved or reduced ejection fraction, and valvular heart failure, in a community-based cohort

Background

The lack of effective therapies for heart failure with preserved ejection fraction (HFpEF) reflects an incomplete understanding of its pathogenesis.

Design

We analysed baseline risk factors for incident HFpEF, heart failure with reduced ejection fraction (HFrEF) and valvular heart failure (VHF) in a community-based cohort.

Methods

We recruited 2101 men and 1746 women ≥60 years of age with hypertension, diabetes, ischaemic heart disease (IHD), abnormal heart rhythm, cerebrovascular disease or renal impairment. Exclusion criteria were known heart failure, left ventricular ejection fraction <50% or valve abnormality >mild in severity. Median follow-up was 5.6 (IQR 4.6-6.3) years.

Results

Median time to heart failure diagnosis in 162 participants was 4.5 (IQR 2.7-5.4) years, 73 with HFpEF, 53 with HFrEF and 36 with VHF. Baseline age and amino-terminal pro-B-type natriuretic peptide levels were associated with HFpEF, HFrEF and VHF. Pulse pressure, IHD, waist circumference, obstructive sleep apnoea and pacemaker were associated with HFpEF and HFrEF; atrial fibrillation (AF) and warfarin therapy were associated with HFpEF and VHF and peripheral vascular disease and low platelet count were associated with HFrEF and VHF. Additional risk factors for HFpEF were body mass index (BMI), hypertension, diabetes, renal dysfunction, low haemoglobin, white cell count and β-blocker, statin, loop diuretic, non-steroidal anti-inflammatory and clopidogrel therapies, for HFrEF were male gender and cigarette smoking and for VHF were low diastolic blood pressure and alcohol intake. BMI, diabetes, low haemoglobin, white cell count and warfarin therapy were more strongly associated with HFpEF than HFrEF, whereas male gender and low platelet count were more strongly associated with HFrEF than HFpEF.

Conclusions

Our data suggest a major role for BMI, hypertension, diabetes, renal dysfunction, and inflammation in HFpEF pathogenesis; strategies directed to prevention of these risk factors may prevent a sizeable proportion of HFpEF in the community.

Trial registration number

NCT00400257, NCT00604006 and NCT01581827.

Age-Related Differential Structural and Transcriptomic Responses in the Hypertensive Heart

While aging is a critical risk factor for heart failure, it remains uncertain whether the aging heart responds differentially to a hypertensive stimuli. Here we investigated phenotypic and transcriptomic differences between the young and aging heart using a mineralocorticoid-excess model of hypertension. Ten-week (“young”) and 36-week (“aging”) mice underwent a unilateral uninephrectomy with deoxycorticosterone acetate (DOCA) pellet implantation (n = 6–8/group) and were followed for 6 weeks. Cardiac structure and function, blood pressure (BP) and the cardiac transcriptome were subsequently examined. Young and aging DOCA mice had high BP, increased cardiac mass, cardiac hypertrophy, and fibrosis. Left ventricular end-diastolic pressure increased in aging DOCA-treated mice in contrast to young DOCA mice. Interstitial and perivascular fibrosis occurred in response to DOCA, but perivascular fibrosis was greater in aging mice. Transcriptomic analysis showed that young mice had features of higher oxidative stress, likely due to activation of the respiratory electron transport chain. In contrast, aging mice showed up-regulation of collagen formation in association with activation of innate immunity together with markers of inflammation including cytokine and platelet signaling. In comparison to younger mice, aging mice demonstrated different phenotypic and molecular responses to hypertensive stress. These findings have potential implications for the pathogenesis of age-related forms of cardiovascular disease, particularly heart failure.

Non-cardiac comorbidities in heart failure with reduced, mid-range and preserved ejection fraction

BACKGROUND

Comorbidities play a major role in heart failure. Whether prevalence and prognostic importance of comorbidities differ between heart failure with preserved ejection fraction (HFpEF), mid-range (HFmrEF) or reduced ejection fraction (HFrEF) is unknown.

METHODS

Patients from index (n = 2516) and validation cohort (n = 1738) of The BIOlogy Study to TAilored Treatment in Chronic Heart Failure (BIOSTAT-CHF) were pooled. Eight non-cardiac comorbidities were assessed; diabetes mellitus, thyroid dysfunction, obesity, anaemia, chronic kidney disease (CKD, estimated glomerular filtration rate < 60 mL/min/1.73 m²), COPD, stroke and peripheral arterial disease. Patients were classified based on ejection fraction. The association of each comorbidity with quality of life (QoL), all-cause mortality and hospitalisation was evaluated.

RESULTS

Patients with complete comorbidity data were included (n = 3499). Most prevalent comorbidity was CKD (50%). All comorbidities showed the highest prevalence in HFpEF, except for stroke. Prevalences of HFmrEF were in between the other entities. COPD was the comorbidity associated with the greatest reduction in QoL. In HFrEF, almost all were associated with a significant reduction in QoL, while in HFpEF only CKD and obesity were associated with a reduction. Most comorbidities in HFrEF were associated with an increased mortality risk, while in HFpEF only CKD, anaemia and COPD were associated with higher mortality risks.

CONCLUSIONS

The highest prevalence of comorbidities was seen in patients with HFpEF. Overall, comorbidities were associated with a lower QoL, but this was more pronounced in patients with HFrEF. Most comorbidities were associated with higher mortality risks, although the associations with diabetes were only present in patients with HFrEF.

Palliative Care and Advance Care Planning in Pulmonary Hypertension

Pulmonary hypertension (PH) is a progressive disease with high associated morbidity and mortality despite the development of novel therapies. Palliative care is a multidisciplinary field focused on optimization of quality of life and overall supportive care for patients and their families in the setting of life-limiting illness. Although the benefits of palliative care in oncology are well described, there are few studies regarding the timing and involvement of palliative care in PH patients. In this paper, we describe the importance of longitudinal advance care planning, including suggestions for addressing difficult topics such as end-of-life care, and the role of palliative care providers in helping guide these discussions throughout the course of the illness.

Hormone treatments in congestive heart failure

The common ultimate pathological feature for all cardiovascular diseases, congestive heart failure (CHF), is now considered as one of the main public health burdens that is associated with grave implications. Neurohormonal systems play a critical role in cardiovascular homeostasis, pathophysiology, and cardiovascular diseases. Hormone treatments such as the newly invented dual-acting drug valsartan/sacubitril are promising candidates for CHF, in addition to the conventional medications encompassing beta receptor blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and mineralocorticoid receptor antagonists. Clinical trials also indicate that in CHF patients with low insulin-like growth factor-1 or low thyroid hormone levels, supplemental treatment with growth hormone or thyroid hormone seems to be cardioprotective; and in CHF patients with volume overload the vasopressin antagonists can relieve the symptoms superior to loop diuretics. Furthermore, a combination of selective glucocorticoid receptor agonist and mineralocorticoid receptor antagonist may be used in patients with diuretic resistance. Finally, the potential cardiovascular efficacy and safety of incretin-based therapies, testosterone or estrogen supplementation needs to be prudently evaluated in large-scale clinical studies. In this review, we briefly discuss the therapeutic effects of several key hormones in CHF.

Comorbidities, Sociodemographic Factors, and Hospitalizations in Outpatients With Heart Failure and Preserved Ejection Fraction

Patients with heart failure and preserved ejection fraction (HFpEF) tend to be older and have a high co-morbidity burden. The impact of co-morbid conditions and sociodemographic risk factors on outcomes in these patients has not been quantified. We evaluated 445 consecutive outpatients with HFpEF, defined as established diagnosis of heart failure (HF) with left ventricular ejection fraction at presentation >40% and no previous left ventricular ejection fraction ≤40%. Patients with specific cardiomyopathies, congenital heart disease, primary right-sided disease, valvular disease, or previous advanced HF therapies were excluded. After 2 years, there were 44 deaths and 609 all-cause hospitalizations; of these, 260 (42.7%) were cardiovascular hospitalizations, including HF, and 173 (28.4%) were specifically for HF. The highest attributable risk for hospitalizations was associated with marital status (single, divorced, and widowed had higher hospitalization rates compared with married patients), hypoalbuminemia, diabetes, atrial fibrillation, and renal dysfunction. The proportion of hospitalizations potentially attributable to these factors was 66.6% (95% confidence interval [CI] 56.4 to 74.4) for all-cause hospitalizations, 76.9% (95% CI 65.2 to 84.6) for cardiovascular hospitalizations, and 83.0% (95% CI 70.3 to 90.3) for HF hospitalizations. For composite end points, the proportion was 46.9% (95% CI 34.0% to 57.3%) for death or all-cause hospitalization, 45.7% (95% CI 29.3% to 58.2%) for death or cardiovascular hospitalization, and 43.7% (95% CI 24.2% to 58.2%) for death or HF-related hospitalization. In conclusion, among outpatients with HFpEF, most hospitalizations could be attributed to co-morbidities and sociodemographic factors. Effects of HF therapies on hospitalizations and related end points may be difficult to demonstrate in these patients. Multidisciplinary approaches are more likely to impact hospitalizations in HFpEF.

Domain Management Approach to Heart Failure in the Geriatric Patient: Present and Future

Heart failure (HF) is a quintessential geriatric cardiovascular condition, with more than 50% of hospitalizations occurring in adults age 75 years or older. In older patients, HF is closely linked to processes inherent to aging, which include cellular and structural changes to the myocardium, vasculature, and skeletal muscle. In addition, HF cannot be considered in isolation of physical functioning, or without the social, psychological, and behavioral dimensions of illness. The role of frailty, depression, cognitive impairment, nutrition, and goals of care are each uniquely relevant to the implementation and success of medical therapy. In this paper, we discuss a model of caring for older adults with HF through a 4-domain framework that can address the unique multidimensional needs and vulnerabilities of this population. We believe that clinicians who embrace this approach can improve health outcomes for older adults with HF.

Biomarker-based phenotyping of myocardial fibrosis identifies patients with heart failure with preserved ejection fraction resistant to the beneficial effects of spironolactone: results from the Aldo-DHF trial

BACKGROUND

Myocardial fibrosis is characterized by excessive cross-linking and deposition of collagen type I and is involved in left ventricular stiffening and left ventricular diastolic dysfunction (LVDD). We investigated whether the effect of spironolactone on LVDD in patients with heart failure with preserved ejection fraction (HFpEF) depends on its effects on collagen cross-linking and/or deposition.

METHODS AND RESULTS

We investigated 381 HFpEF patients from the multicentre, randomized, placebo-controlled Aldo-DHF trial with measures of the E:e' ratio. The ratio of serum carboxy-terminal telopeptide of collagen type I to serum matrix metalloproteinase-1 (CITP:MMP-1, an inverse index of myocardial collagen cross-linking) and serum carboxy-terminal propeptide of procollagen type I (PICP, a direct index of myocardial collagen deposition) were determined at baseline and after 1-year treatment with spironolactone 25 mg once daily or placebo. Patients were classified by CITP:MMP-1 and PICP tertiles at baseline. While CITP:MMP-1 tertiles at baseline interacted (P < 0.05) with spironolactone effect on E:e', PICP tertiles did not. In fact, while spironolactone treatment did not modify E:e' in patients with lower CITP:MMP-1 levels, this ratio was significantly reduced in the remaining spironolactone-treated patients. In addition, PICP was unchanged in patients with lower CITP:MMP-1 levels but was reduced in the remaining spironolactone-treated patients.

CONCLUSIONS

A biochemical phenotype of high collagen cross-linking identifies HFpEF patients resistant to the beneficial effects of spironolactone on LVDD. It is suggested that excessive collagen cross-linking, which stabilizes collagen type I fibres, diminishes the ability of spironolactone to reduce collagen deposition in these patients.