Pulmonary hypertension in heart failure with preserved ejection fraction: a target for therapy?

Research Update on the Pathophysiological Mechanisms of Heart Failure with Preserved Ejection Fraction

Heart failure (HF) is a serious clinical syndrome, usually occurs at the advanced stage of various cardiovascular diseases, featured by high mortality and rehospitalization rate. According to left ventricular (LV) ejection fraction (LVEF), HF has been categorized as HF with reduced EF (HFrEF; LVEF<40%), HF with mid-range EF (HFmrEF; LVEF 40-49%), and HF with preserved EF (HFpEF; LVEF ≥50%). HFpEF accounts for about 50% of cases of heart failure and has become the dominant form of heart failure. The mortality of HFpEF is similar to that of HFrEF. There are no welldocumented treatment options that can reduce the morbidity and mortality of HFpEF now. Understanding the underlying pathological mechanisms is essential for the development of novel effective therapy options for HFpEF. In recent years, significant research progress has been achieved on the pathophysiological mechanism of HFpEF. This review aimed to update the research progress on the pathophysiological mechanism of HFpEF.

Potential diabetic cardiomyopathy therapies targeting pyroptosis: A mini review

Pyroptosis is primarily considered a pro-inflammatory class of caspase-1- and gasdermin D (GSDMD)-dependent programmed cell death. Inflammasome activation promotes the maturation and release of interleukin (IL)-1β and IL-18, cleavage of GSDMD, and development of pyroptosis. Recent studies have reported that NLRP3 inflammasome activation-mediated pyroptosis aggravates the formation and development of diabetes cardiomyopathy (DCM). These studies provide theoretical mechanisms for exploring a novel approach to treat DCM-associated cardiac dysfunction. Accordingly, this review aims to summarize studies that investigated possible DCM therapies targeting pyroptosis and elucidate the molecular mechanisms underlying NLRP3 inflammasome-mediated pyroptosis, and its potential association with the pathogenesis of DCM. This review may serve as a basis for the development of potential pharmacological agents as novel and effective treatments for managing and treating DCM.

Murine Models of Heart Failure with Preserved Ejection Fraction: a "Fishing Expedition"

Heart failure with preserved ejection fraction (HFpEF) is characterized by signs and symptoms of HF in the presence of a normal left ventricular (LV) ejection fraction (EF). Despite accounting for up to 50% of all clinical presentations of HF, the mechanisms implicated in HFpEF are poorly understood, thus precluding effective therapy. The pathophysiological heterogeneity in the HFpEF phenotype also contributes to this disease and likely to the absence of evidence-based therapies. Limited access to human samples and imperfect animal models that completely recapitulate the human HFpEF phenotype have impeded our understanding of the mechanistic underpinnings that exist in this disease. Aging and comorbidities such as atrial fibrillation, hypertension, diabetes and obesity, pulmonary hypertension and renal dysfunction are highly associated with HFpEF. Yet, the relationship and contribution between them remains ill-defined. This review discusses some of the distinctive clinical features of HFpEF in association with these comorbidities and highlights the advantages and disadvantage of commonly used murine models, used to study the HFpEF phenotype.

Combined Post- and Precapillary Pulmonary Hypertension in Patients With Heart Failure

BACKGROUND

Pulmonary hypertension (PH) is a well-recognized complication of left ventricular heart failure (HF).

HYPOTHESIS

Differences exist in demographic, clinical, hemodynamic, and survival characteristics of patients with left ventricular HF who have combined postcapillary and precapillary PH (CpcPH), isolated postcapillary PH, or no PH.

METHODS

A secondary data analysis was conducted using a large prospective database of patients undergoing right heart catheterization from 1994 to 2012. One-year mortality postcatheterization was assessed between PH groups using Kaplan-Meier and log-rank techniques, as well as a multivariate Cox proportional hazards model adjusted for age, sex, diabetes, chronic kidney disease, atrial fibrillation, and chronic obstructive pulmonary disease. Mortality rates were calculated for each group as deaths per 100 person-years.

RESULTS

Of the 724 patients identified, 29.4% (n = 213) had no evidence of PH, 63.1% (n = 457) had isolated postcapillary PH, and 7.5% (n = 54) had CpcPH. Compared with no PH, there was an increased mortality rate within 1 year for CpcPH patients (crude hazard ratio: 5.22, 95% confidence interval: 2.06-13.22), but not for isolated postcapillary PH patients (crude hazard ratio: 2.12, 95% confidence interval: 0.99-4.57). Adjusted analyses revealed similar results. Mortality rates per 100 person-years were 3.9, 8.4, and 21.0 for no PH, isolated postcapillary PH, and CpcPH patients, respectively.

CONCLUSIONS

Heart failure patients with CpcPH are associated with increased death rate 1 year post-cardiac catheterization, compared with patients without PH. They are a high-risk PH group and should be evaluated and diagnosed earlier in the disease state.

Pulmonary arterial hypertension: Basic knowledge for clinicians

Pulmonary arterial hypertension is a progressive syndrome based on diverse aetiologies, which is characterized by a persistent increase in pulmonary vascular resistance and overload of the right ventricle, leading to heart failure and death. Currently, none of the available treatments is able to cure pulmonary arterial hypertension; additional research is therefore needed to unravel the associated pathophysiological mechanisms. This review summarizes current knowledge related to this disorder, and the several experimental animal models that can mimic pulmonary arterial hypertension and are available for translational research.

Pulmonary hypertension and right heart failure in heart failure with preserved left ventricular ejection fraction: pathophysiology and natural history

PURPOSE OF REVIEW

Pulmonary hypertension and right heart failure are common findings in patients suffering from heart failure with preserved ejection fraction (HFpEF). In this review, we summarize our current understanding of the pathophysiology of pulmonary hypertension related to heart failure.

RECENT FINDINGS

HFpEF is a clinical syndrome with increasing prevalence and a mortality rate similar to heart failure with reduced ejection fraction. Because the pathophysiology and even the definition of this disease are still controversial, we will first outline the current conceptual framework around heart failure with preserved ejection fraction. Next, we will outline our current knowledge on the pathophysiology of pulmonary hypertension related to left ventricular failure and diastolic dysfunction. Diastolic dysfunction induces pulmonary hypertension through passive transmission of elevated end diastolic pressures, reactive pulmonary vasoconstriction, and vascular remodeling. Eventually, right ventricular failure develops that can further potentiate left ventricular failure because of their close mechanical, cellular, and biochemical integration.

SUMMARY

Exciting new studies have led to an increased understanding of the underlying pathophysiology and indicate that pulmonary hypertension in heart failure may be treatable.