Progression of Left Ventricular Dysfunction and Remodelling under Optimal Medical Therapy in CHF Patients: Role of Individual Genetic Background

Determinants of ejection fraction improvement in heart failure patients with reduced ejection fraction

AIMS

This study aimed to investigate the prognostic value of dynamic changes in left ventricular ejection fraction (EF) for cardiovascular (CV) outcomes in an all-comer heart failure (HF) population with reduced EF (HFrEF, EF < 40%). We sought to identify independent factors related to improvement in EF and to identify risk factors for increased risk of CV events in the subgroups of improved EF (iEF) and non-improved EF (niEF), respecively.

METHODS AND RESULTS

This is a retrospective sub-analysis from the REDEAL HF trial, which included consecutive patients with chronic HF who were hospitalized from July 2009 to December 2017. Baseline and follow-up echocardiography data (interval ≥12 months) of 573 consecutive patients with HFrEF were analysed. iEF was defined as absolute improvement in EF ≥ 10% and follow-up EF over 40%. The primary endpoint was defined as a composite endpoint of cardiovascular (CV) death, CV hospitalization, or appropriate implantable cardioverter-defibrillator (ICD) therapy for ventricular arrhythmia. EF improved in 37.2% of patients with HFrEF during follow-up (median period of 17 months). iEF was independently associated with shorter HF duration (>4 vs. ≤4 years, odd ratio [OR] = 0.477, 95% CI 0.305-0.745), no coronary artery disease (CAD vs. no CAD, OR = 0.583, 95% CI 0.396-0.858), and no ICD implantation (ICD vs. no ICD, OR = 0.341, 95% CI 0.228-0.511). Compared with niEF, iEF was significantly and independently associated with lower all-cause mortality (22.1% vs. 31.1%, P = 0.019; hazard ratio [HR] = 0.674, 95% CI 0.469-0.968), lower CV mortality (8.9% vs. 16.1%, P = 0.015; HR = 0.539, 95% CI 0.317-0.916), and lower CV events risk (27.2% vs. 49.2%, P < 0.001; HR 0.519, 95% CI 0.381-0.708), after adjustment for age, sex, duration of HF, and other clinical risk factors. Hypertension (HR = 2.452, P = 0.032) and elevated N-terminal prohormone of brain natriuretic peptide (NT-proBNP >1153 pg/mL, HR = 4.372, P < 0.001) were identified as independent risk factors for CV events in the iEF subgroup. ICD implantation (HR = 1.533, P = 0.011), elevated NT-proBNP (HR = 1.626, P = 0.018), increased left atrial volume index (HR = 1.461, P = 0.021), reduced lateral mitral annular plane systolic excursion (HR = 1.478, P = 0.025), and reduced tricuspid plane systolic excursion (HR = 1.491, P = 0.039) were identified as risk factors for CV events in the niEF subgroup.

CONCLUSIONS

Improvement in EF is independently related to the longer survival and lower CV related mortality and hospitalization rate of HFrEF. Elevated baseline NT-proBNP is identified as the strongest prognostic factor associated with increased CV events risk in HFrEF patients both with and without improved EF, regardless of age, sex, duration of HF, and other clinical risk factors.

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

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

Heart Failure With Mid-range or Recovered Ejection Fraction: Differential Determinants of Transition

The recent definition of an intermediate clinical phenotype of heart failure (HF) based on an ejection fraction (EF) of between 40% and 49%, namely HF with mid-range EF (HFmrEF), has fuelled investigations into the clinical profile and prognosis of this patient group. HFmrEF shares common clinical features with other HF phenotypes, such as a high prevalence of ischaemic aetiology, as in HF with reduced EF (HFrEF), or hypertension and diabetes, as in HF with preserved EF (HFpEF), and benefits from the cornerstone drugs indicated for HFrEF. Among the HF phenotypes, HFmrEF is characterised by the highest rate of transition to either recovery or worsening of the severe systolic dysfunction profile that is the target of disease-modifying therapies, with opposite prognostic implications. This article focuses on the epidemiology, clinical characteristics and therapeutic approaches for HFmrEF, and discusses the major determinants of transition to HFpEF or HFrEF.

Late Versus Early Myocardial Remodeling After Acute Myocardial Infarction: A Comparative Review on Mechanistic Insights and Clinical Implications

In the setting of acute myocardial infarction (AMI), adverse myocardial remodeling (AMR) has been universally regarded as an early-onset phenomenon generally arising within the first few weeks (usually within days in the infarct zone) following myocardial injury. On the other hand, onset of cardiac morphological changes in this setting may potentially extend far beyond this time frame (usually beyond several months after the index AMI), suggesting a prolonged latent period in certain cases. In clinical practice, this delayed form of post-AMI remodeling, namely late AMR, has emerged as an interesting and underrecognized phenomenon with poorly understood mechanisms. Notably, systemic inflammation and associated growth factors seem to play a pivotal role in this setting. Accordingly, the present article primarily aims to discuss potential mechanisms and clinical implications of late AMR (in a comparative manner with its classical early counterpart) among AMI survivors along with a particular emphasis on potential benefits of certain anti-inflammatory strategies in this setting.

Heart Failure With Improved Ejection Fraction: Is it Possible to Escape One's Past?

Among patients with heart failure with reduced ejection fraction, investigators have repeatedly identified a subgroup whose left ventricular ejection fraction and structural remodeling can improve to normal or nearly normal levels with or without medical therapy. This subgroup of patients with "heart failure with improved ejection fraction" has distinct clinical characteristics and a more favorable prognosis compared with patients who continue to have reduced ejection fraction. However, many of these patients also manifest clinical and biochemical signs of incomplete resolution of heart failure pathophysiology and remain at some risk of adverse outcomes, thus indicating that they may not have completely recovered. Although rigorous evidence on managing these patients is sparse, there are several reasons to recommend continuation of heart failure therapies, including device therapies, to prevent clinical deterioration. Notable exceptions to this recommendation may include patients who recover from peripartum cardiomyopathy, fulminant myocarditis, or stress cardiomyopathy, whose excellent long-term prognoses may imply true myocardial recovery. More research on these patients is needed to better understand the mechanisms that lead to improvement in ejection fraction and to guide their clinical management.