Heart failure with preserved ejection fraction: the missing pieces in diagnostic imaging

Improved identification of left atrial enlargement in patients with obesity

Accurate standardization of left atrium volume (LAV) in patients with obesity is challenging. The aim of this study was to investigate and to examine the relation between LAV indexed to height2 and left atrial function in patients with moderate to severe obesity. Echocardiograms of patients with moderate to severe obesity (body mass index (BMI) ≥ 35 kg/m2) without known cardiac disease were analyzed. LAV was indexed to body surface area (BSA) and height2, and patients were divided into those with or without left atrial enlargement (LAE) based on normalization using either BSA (LAEbsa) or height2 (LAEh2). Using speckle tracking echocardiography, LA reservoir strain (LASr), LA conduit strain (LAScd), and LA contractile strain (LASct) were assessed as a measure of LA function. LA dysfunction was defined as LASct < 14%. A total of 142 patients were included in the analysis of whom 54.2% had LAEh2 and 18.3% LAEBSA. The LAEh2 group had significantly lower LASct (12.2% ± 3.2% vs. 13.6% ± 4.5%, p = 0.019) as compared to the patients without LAEh2. Significantly more patients with LA dysfunction would be correctly identified by LAEh2 than by LAEBSA (41.5% vs. 15.0%, p < 0.001). In patients with moderate to severe obesity, the use of LAEh2 identified significantly more patients with decreased LA function. LAVh2 should be preferred over LAVBSA in patients with moderate to severe obesity.

Association of Mild-to-Moderate Aortic Regurgitation With Outcomes in Heart Failure With Preserved Ejection Fraction

OBJECTIVE

To assess aortic regurgitation (AR) prevalence, its hemodynamic effect, and long-term prognostic implications in patients admitted with de novo or worsened heart failure with preserved ejection fraction (HFpEF).

METHODS

Consecutive patients hospitalized with de novo or worsened HFpEF between 2014 and 2020 were enrolled. Patients with more than moderate aortic and/or mitral valve disease were excluded. Based on the presence and degree of AR, patients were divided into those without AR, those with mild, and those with moderate AR. Data on cardiovascular death, heart failure (HF) rehospitalization, and their composite (major adverse cardiovascular events) were collected.

RESULTS

The final study population consisted of 458 HFpEF patients: 156 (34.1%) with mild-AR, 153 (33.4%) with moderate-AR, and the remaining 149 (32.5%) with no AR. Mild-to-moderate AR patients were older, with larger left atrium-left ventricle (LV) volumes, greater LV mass index, higher filling pressure, and prevalence of diastolic dysfunction compared with the no-AR group (all P<.05). During 5-year follow-up, 113 patients died of cardiovascular causes, 124 patients were rehospitalized for HF, whereas 196 experienced the composite endpoint. Mild-to-moderate AR was identified as an independent predictor of all-cause death (HR, 1.62; 95% CI, 1.14 to 1.58; P=.04) and major adverse cardiovascular event occurrence (HR, 1.48; 95% CI, 1.05 to 2.09; P=.02). A total of 126 (35.5%) of 355 patients showed progression of AR at follow-up echocardiography.

CONCLUSION

Mild-to-moderate AR is common among patients hospitalized for HFpEF. It is associated with adverse LV remodeling and worse long-term outcomes. These findings warrant further prospective studies addressing the importance of AR in prognostic stratification and exploring therapeutic strategies to mitigate its hemodynamic effect on HF.

Safety and effectiveness of standardized exercise training in patients with pulmonary hypertension associated with heart failure with preserved ejection fraction (TRAIN-HFpEF-PH): study protocol for a randomized controlled multicenter trial

BACKGROUND

Left heart failure (HF) is characterized by an elevation in left-sided filling pressures, causing symptoms of dyspnea, impairing exercise capacity, and leading to pulmonary venous congestion and secondary pulmonary hypertension (PH). There is an increased incidence of PH associated with left heart disease, particularly with heart failure with preserved ejection fraction (HFpEF-PH). Treatment possibilities in HFpEF-PH are non-specific and very limited, thus additional pharmacological and non-pharmacological therapeutic strategies are needed. Various types of exercise-based rehabilitation programs have been shown to improve exercise capacity and quality of life (QoL) of HF and PH patients. However, no study focused on exercise training in the population of HFpEF-PH. This study is designed to investigate whether a standardized low-intensity exercise and respiratory training program is safe and may improve exercise capacity, QoL, hemodynamics, diastolic function, and biomarkers in patients with HFpEF-PH.

METHODS

A total of 90 stable patients with HFpEF-PH (World Health Organization functional class II-IV) will be randomized (1:1) to receive a 15-week specialized low-intensity rehabilitation program, including exercise and respiratory therapy and mental gait training, with an in-hospital start, or standard care alone. The primary endpoint of the study is a change in 6-min walk test distance; secondary endpoints are changes in peak exercise oxygen uptake, QoL, echocardiographic parameters, prognostic biomarkers, and safety parameters.

DISCUSSION

To date, no study has investigated the safety and efficacy of exercising specifically in the HFpEF-PH population. We believe that a randomized controlled multicenter trial, which protocol we are sharing in this article, will add important knowledge about the potential utility of a specialized low-intensity exercise and respiratory training program for HFpEF-PH and will be valuable in finding optimal treatment strategies for these patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05464238. July 19, 2022.

Challenges in the management of people with heart failure with preserved ejection fraction (HFpEF) in primary care: A qualitative study of general practitioner perspectives

OBJECTIVES

To explore the perspectives of general practitioners (GPs) on the identification and management of people, including those from ethnic minority groups, with Heart Failure with Preserved Ejection Fraction (HFpEF).

METHODS

Qualitative study. Semi-structured, face-to-face or telephone interviews and focus groups were conducted with 35 GPs in England, which were audio-recorded and transcribed verbatim. Framework analysis was used to manage and interpret data.

RESULTS

Themes presented reflect four inter-related challenges: GPs' 1) lack of understanding HFpEF, impacting on 2) difficulties in communicating the diagnosis, leading to 3) uncertainty in managing people with HFpEF, further hindered by (4) discontinuity across the primary/secondary interface. All were considered more challenging by GPs when managing people from different cultures and languages.

DISCUSSION

HFpEF is not well understood by GPs, leading to diagnostic difficulty, management uncertainty and potential inequity in care offered. People with HFpEF are seen as complex, with multiple long-term conditions and requiring personalised care. Challenges in their management occur across the healthcare system. This study has identified learning needs for GPs around identification and on-going support for people with HFpEF in primary care. It will contribute to the development of more flexible and patient-centred pathways across the primary/secondary care interface.

Microvascular Dysfunction in Skeletal Muscle Precedes Myocardial Vascular Changes in Diabetic Cardiomyopathy: Sex-Dependent Differences

Aim

To uncover sex-related microvascular abnormalities that underlie the early presentation of reduced perfusion in leg skeletal muscle in a type II rat model of diabetic cardiomyopathy.

Methods and Results

Diabetes was induced using a non-obese, diet-based, low-dose streptozotocin model in adult female (18 diabetic, 9 control) and male rats (29 diabetic, 11 control). Time-course monitoring over 12 months following diabetes induction was performed using echocardiography, treadmill exercise, photoacoustic imaging, flow-mediated dilation (FMD), histopathology, and immunohistochemistry. Diabetic rats maintained normal weights. Hypertension appeared late in both diabetic males (7 months) and females (10 months), while only diabetic males had elevated cholesterol (7 months). On echocardiography, all diabetic animals maintained normal ejection fraction and exhibited diastolic dysfunction, mild systolic dysfunction, and a slightly enlarged left ventricle. Exercise tolerance declined progressively and early in males (4 months), later in females (8 months); FMD showed lower baseline femoral arterial flow but unchanged reactivity in both sexes (5 months); and photoacoustic imaging showed lower tissue oxygen saturation in the legs of diabetic males (4 months) and diabetic females (10 months). Myocardial perfusion was normal in both sexes. Histopathology at the final timepoint of Month 10 (males) and Month 12 (females) revealed that myocardial microvasculature was normal in both vessel density and structure, thus explaining normal perfusion on imaging. However, leg muscle microvasculature exhibited perivascular smooth muscle thickening around small arterioles in diabetic females and around large arterioles in diabetic males, explaining the depressed readings on photoacoustic and FMD. Histology also confirmed the absence of commonly reported HFpEF markers, including microvessel rarefaction, myocardial fibrosis, and left ventricular hypertrophy.

Conclusion

Exercise intolerance manifesting early in the progression of diabetic cardiomyopathy can be attributed to decreased perfusion to the leg skeletal muscle due to perivascular smooth muscle thickening around small arterioles in females and large arterioles in males. This microvascular abnormality was absent in the myocardium, where perfusion levels remained normal throughout the study. We conclude that although skeletal muscle microvascular dysfunction of the vasculature presents at different levels depending on sex, it consistently presents early in both sexes prior to overt cardiac changes such as rarefaction, fibrosis, or hypertrophy.

Prognostic Impact of Echocardiographic Diastolic Dysfunction on Outcomes in Patients With Heart Failure With Preserved Ejection Fraction - Insights From the PURSUIT-HFpEF Registry

BACKGROUND

Although diastolic dysfunction is important pathophysiology in heart failure with preserved ejection fraction (HFpEF), its prognostic impact in HFpEF patients, including those with atrial fibrillation (AF), remains to be elucidated.Methods and Results:We included the data for 863 patients (321 patients with AF) registered in a prospective multicenter observational study of patients with HFpEF. Patients were divided into 3 groups according to the 2016 ASE/EACVI recommendations. The primary endpoint was a composite of all-cause death or HF rehospitalization. Median age was 83 years, and 55.5% were female. 196 (22.7%) were classified with normal diastolic function (ND), 253 (29.3%) with indeterminate (ID) and 414 (48.0%) with diastolic dysfunction (DD). The primary endpoint occurred more frequently in patients with DD than in those with ND or ID (log-rank P<0.001 for DD vs. ND, and log-rank P=0.007 for DD vs. ID, respectively). Taking ND as the reference, multivariable Cox regression analysis revealed that DD (hazard ratio (HR): 1.57, 95% confidence interval (CI):1.06-2.32, P=0.024) was independently associated with the composite endpoint, whereas ID (HR: 1.28, 95% CI: 0.84-1.95, P=0.255) was not. DD was associated with the composite endpoint in both patients with and without AF.

CONCLUSIONS

HFpEF patients classified with DD using the 2016 ASE/EACVI recommendations had worse clinical outcomes than those with ND or ID. DD may be considered a prognostic marker in patients with HFpEF regardless of AF.

Diagnostic algorithm for HFpEF: how much is the recent consensus applicable in clinical practice?

Heart failure with preserved ejection fraction (HFpEF) represents an important cardiovascular entity with increasing prevalence and relatively high mortality. The agreement about diagnostic algorithm for HFpEF is still missing. Echocardiographic approach remains the cornerstone in HFpEF diagnosis. Echocardiographic diastolic stress test provides numerous useful parameters that correlated well with indexes obtained by cardiac catheterization. Recently published consensus recommended new scoring system that included functional and structural echocardiographic parameters, as well as biomarkers. The new score for evaluation of HFpEF introduces a new set of parameters and proposed novel cutoff values for some of them. There are several important points that need to be resolved before full acceptance and clinical usage. First, some cutoff values are new and represent the result of expert consensus, without previous validation. Second, many patients with hypertension, obesity, and diabetes would be referred for further investigations as the result of this scoring, which is difficult to achieve in clinical circumstances. Third, the consensus equalized non-invasive and invasive diastolic stress tests in diagnosing of HFpEF, which is not a small issue. Namely, even though cardiac catheterization provides the final confirmation of elevated left ventricular filling pressures, it is still an invasive method, associated with procedural risk and other limitations. The aim of this review was to summarize the current knowledge diagnosis of HFpEF, as well as the recent consensus about diagnostic algorithm in patients with suspected HFpEF with its advantages and disadvantages.

[Heart Failure With Preserved Ejection Fraction: A Problem Of Contemporary Cardiology]

Heart failure with preserved ejection fraction (HFpEF) is a frequent and overlooked medical condition that represents a great challenge for diagnosis and treatment. Current data shows a temporal trend towards a higher prevalence of HFpEF, even above heart failure with reduced ejection fraction (HFrEF). The pathophysiology of HFpEF is heterogeneous and involves several factors such as genetics, lifestyle, and cardiac and non-cardiac comorbidities. These factors result in remodeling, maladaptation and cardiac stiffness, that later on cause dyspnea, exercise intolerance, and fatigue. Although the mortality outcome of HFpEF is as high as HFrEF, no specific therapy has demonstrated overall benefit in these patients; which is why future therapies will bet on an individualized approach according to the patients phenotype.