Retinal Vascular Changes in Heart Failure with Preserved Ejection Fraction Using Optical Coherence Tomography Angiography

Background: Systemic microvascular regression and dysfunction are considered important underlying mechanisms in heart failure with preserved ejection fraction (HFpEF), but retinal changes are unknown. Methods: This prospective study aimed to investigate whether retinal microvascular and structural parameters assessed using optical coherence tomography angiography (OCT-A) differ between patients with HFpEF and control individuals (i.e., capillary vessel density, thickness of retina layers). We also aimed to assess the associations of retinal parameters with clinical and echocardiographic parameters in HFpEF. HFpEF patients, but not controls, underwent echocardiography. Macula-centered 6 × 6 mm volume scans were computed of both eyes. Results: Twenty-two HFpEF patients and 24 controls without known HFpEF were evaluated, with an age of 74 [68-80] vs. 68 [58-77] years (p = 0.027), and 73% vs. 42% females (p = 0.034), respectively. HFpEF patients showed vascular degeneration compared to controls, depicted by lower macular vessel density (p < 0.001) and macular ganglion cell-inner plexiform layer thickness (p = 0.025), and a trend towards lower total retinal volume (p = 0.050) on OCT-A. In HFpEF, a lower total retinal volume was associated with markers of diastolic dysfunction (septal e', septal and average E/e': R2 = 0.38, 0.36, 0.25, respectively; all p < 0.05), even after adjustment for age, sex, diabetes mellitus, or atrial fibrillation. Conclusions: Patients with HFpEF showed clear levels of retinal vascular changes compared to control individuals, and retinal alterations appeared to be associated with markers of more severe diastolic dysfunction in HFpEF. OCT-A may therefore be a promising technique for monitoring systemic microvascular regression and cardiac diastolic dysfunction.

The prognostic value of sleep disordered breathing and the hypoxemic burden in HFpEF patients

Background

Heart failure with preserved ejection fraction (HFpEF) is an important health care problem, responsible for a decreased quality of life, high health care costs, and a poor prognosis. Sleep disordered breathing (SDB) is suggested to be an important comorbidity in HFpEF, but its prevalence is probably underestimated due to limited SDB screening in clinical practice. Currently, no parameter reflects the full complexity and prognostic effect of SDB in HFpEF. Time spent with an oxygen saturation below 90% (T90), representing the hypoxemic burden, is an independent predictor of mortality and is superior compared to the widely accepted apnoea hypopnea index (AHI) in patients with HF with reduced ejection fraction (HFrEF). However, this association has not been explored in HFpEF patients.

Purpose

This study investigates the prevalence of SDB, comprising the diagnoses obstructive sleep apnoea and central sleep apnoea, in a HFpEF cohort. Moreover, the prognostic association of hypoxemic burden in SDB, expressed as T90, with more frequent HF hospitalizations or all-cause mortality is assessed in HFpEF patients.

Methods

Patients were prospectively included from our specialised HFpEF outpatient clinic from August 2017 until July 2021. All patients underwent a detailed diagnostic workup. An at home sleep monitoring device was used to obtain oximetry data, including T90, and information on respiratory effort, nasal flow and snoring. The patients were divided into tertiles based on T90 or AHI. In these tertiles pairwise Kaplan-Meier analysis was conducted to compare the probability of the composite endpoint of HF hospitalization or all-cause mortality. A Bonferroni correction was made with a statistical significance of p&lt;0.0167.

Results

This analysis comprises 126 HFpEF patients, with a median age of 75 [70–80] years, 86 (68.3%) patients were female. In total 60 (47.6%) patients were diagnosed with SDB. The median T90 value was 13.7 minutes, with tertiles low (&lt;2.8 min), middle (2.8–31.2 min), and high (&gt;31.2 minutes). The mean follow up time was 40 months (95% CI 37 to 42) and in total 22 patients (17.5%) reached the composite endpoint. Kaplan-Meier analysis showed a gradual higher probability of HF hospitalization or death with higher T90 tertiles, with a significant difference in the highest compared to the lowest T90 tertile (χ2=7.4, p=0.006) (figure 1). Kaplan Meier analysis comparing tertiles based on the AHI (AHI &lt;5.8; 5.8–12.2; &gt;12.2) showed no different probability of the composite endpoint (χ2=3.1 p=0.208).

Conclusion

SDB is highly prevalent in HFpEF and the hypoxemic burden (expressed as T90) is an important prognostic factor. T90 may be a superior prognostic marker in HFpEF compared to the widely accepted AHI. Future research should evaluate whether targeting the hypoxemic burden in HFpEF treatment is effective in improving the prognosis.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Dutch Heart Foundation

The Role of Systemic Microvascular Dysfunction in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a condition with increasing incidence, leading to a health care problem of epidemic proportions for which no curative treatments exist. Consequently, an urge exists to better understand the pathophysiology of HFpEF. Accumulating evidence suggests a key pathophysiological role for coronary microvascular dysfunction (MVD), with an underlying mechanism of low-grade pro-inflammatory state caused by systemic comorbidities. The systemic entity of comorbidities and inflammation in HFpEF imply that patients develop HFpEF due to systemic mechanisms causing coronary MVD, or systemic MVD. The absence or presence of peripheral MVD in HFpEF would reflect HFpEF being predominantly a cardiac or a systemic disease. Here, we will review the current state of the art of cardiac and systemic microvascular dysfunction in HFpEF (Graphical Abstract), resulting in future perspectives on new diagnostic modalities and therapeutic strategies.

Improving diagnosis and risk stratification across the ejection fraction spectrum: the Maastricht Cardiomyopathy registry

AIMS

Heart failure (HF) represents a clinical syndrome resulting from different aetiologies and degrees of heart diseases. Among these, a key role is played by primary heart muscle disease (cardiomyopathies), which are the combination of multifactorial environmental insults in the presence or absence of a known genetic predisposition. The aim of the Maastricht Cardiomyopathy registry (mCMP-registry; NCT04976348) is to improve (early) diagnosis, risk stratification, and management of cardiomyopathy phenotypes beyond the limits of left ventricular ejection fraction (LVEF).

METHODS AND RESULTS

The mCMP-registry is an investigator-initiated prospective registry including patient characteristics, diagnostic measurements performed as part of routine clinical care, treatment information, sequential biobanking, quality of life and economic impact assessment, and regular follow-up. All subjects aged ≥16 years referred to the cardiology department of the Maastricht University Medical Center (MUMC+) for HF-like symptoms or cardiac screening for cardiomyopathies are eligible for inclusion, irrespective of phenotype or underlying causes. Informed consented subjects will be followed up for 15 years. Two central approaches will be used to answer the research questions related to the aims of this registry: (i) a data-driven approach to predict clinical outcome and response to therapy and to identify clusters of patients who share underlying pathophysiological processes; and (ii) a hypothesis-driven approach in which clinical parameters are tested for their (incremental) diagnostic, prognostic, or therapeutic value. The study allows other centres to easily join this initiative, which will further boost research within this field.

CONCLUSIONS

The broad inclusion criteria, systematic routine clinical care data-collection, extensive study-related data-collection, sequential biobanking, and multi-disciplinary approach gives the mCMP-registry a unique opportunity to improve diagnosis, risk stratification, and management of HF and (early) cardiomyopathy phenotypes beyond the LVEF limits.