Haemodynamic and metabolic phenotyping of patients with aortic stenosis and preserved ejection fraction: A specific phenotype of heart failure with preserved ejection fraction?

Impact of diabetes and glycemic status on ventricular-arterial coupling in the general population

BACKGROUND/AIMS

Ventricular-arterial coupling (VAC) plays a crucial role in cardiovascular physiology, affecting cardiac function and arterial properties for optimal organ perfusion. Considering that diabetes mellitus (DM) is a known risk factor for incident heart disease and vascular damage, this study aims to investigate whether changes in VAC due to DM occur earlier, even before the onset of clinically evident cardiovascular disease in the general population.

METHODS

This retrospective study included 2,884 participants (mean age 57 years, 48% male) of the Swedish CArdioPulmonary BioImage Study (SCAPIS), where data on echocardiography and Pulse wave velocity (PWV) were available. Of these, 162 individuals (6%) had prevalent type 2 diabetes (DM), and 334 (12%) had prediabetes. VAC was quantified as the ratio of PWV to Global longitudinal strain (GLS). Linear regression models were used to assess associations between glycemic status (DM, prediabetes), HbA1c, fasting plasma glucose (fP-glucose), and VAC, adjusting for relevant covariates.

RESULTS

I the fully adjusted model, prevalent DM and the combination of DM and prediabetes were significantly associated with increased values of PWV/GLS (Beta = 0.28, p < 0.001 and Beta = 0.14, p < 0.001 respectively), while no significant association was found between prediabetes and PWV/GLS. Increasing values of HbA1c and fP-glucose were significantly associated with higher values of PWV/GLS (Beta = 0.01,p < 0.001 and Beta = 0.07,p < 0.001, respectively) signaling worse VAC. In participants without prevalent DM, higher HbA1c levels were linked to increased PWV/GLS in the age- and sex-adjusted model; however, this association was attenuated after further adjustment for additional confounders. Conversely, fP-glucose remained significantly associated with elevated PWV/GLS across all adjusted models.

CONCLUSIONS

This study demonstrates a significant association between DM and impaired VAC, as reflected by elevated PWV/GLS, while no such link was observed in prediabetes. The transition from prediabetes to DM appears critical for VAC deterioration. Additionally, higher HbA1c and fP-glucose levels, even in non-diabetic individuals, were associated with worsened VAC, highlighting the impact of glycemic control on vascular function.

Heart Failure With Preserved Ejection Fraction Phenotype Is Associated With Early Symptom Onset in Aortic Stenosis and Residual Symptoms After Transcatheter Aortic Valve Implantation

BACKGROUND

Aortic stenosis can lead to cardiac adaptations and symptoms similar to heart failure with preserved ejection fraction. We hypothesized that a heart failure with preserved ejection fraction phenotype in aortic stenosis is associated with earlier onset of symptoms and reduced symptomatic response after transcatheter aortic valve implantation (TAVI).

METHODS AND RESULTS

This retrospective cohort study included 469 patients with moderate aortic stenosis. We determined heavy, hypertension, atrial fibrillation, pulmonary, elder, filling pressure (H2FPEF) score at diagnosis and compared aortic peak jet velocity at onset of dyspnea in patients with low (<6) and high (≥6) H2FPEF score. In a separate cohort of 601 patients undergoing TAVI, we compared New York Heart Association class, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and cardiovascular mortality post-TAVI between patients with low and high H2FPEF scores. In patients with aortic stenosis and a high H2FPEF score (n=43, 9.2%), the median peak jet velocity at onset of dyspnea was 4.2 versus 4.4 m/s in patients with a low H2FPEF score (P<0.001). After TAVI, a high H2FPEF score (n=123, 20%) was associated with a lower proportion of New York Heart Association class I at 30 days (49% versus 61%; P=0.04), persistently elevated NT-proBNP, and higher 5-year rate of cardiovascular mortality (36% versus 30%; P=0.012), compared with a low H2FPEF score.

CONCLUSIONS

Patients with aortic stenosis with a heart failure with preserved ejection fraction phenotype are more likely to develop symptoms at lower gradients and have worse outcomes post-TAVI. Randomized trials are warranted to investigate whether medical therapy targeted at heart failure with preserved ejection fraction delays onset of symptoms and improves symptomatic response after TAVI.

Advances in Pathophysiological Mechanisms of Degenerative Aortic Valve Disease

Degenerative aortic valve disease (DAVD) represents the most prevalent valvular ailment among the elderly population, which significantly impacts their physical well-being and potentially poses a lethal risk. Currently, the underlying mechanisms of DAVD remain incompletely understood. While the progression of this disease has traditionally been attributed to degenerative processes associated with aging, numerous recent studies have revealed that heart valve calcification may represent a response of valve tissue to a specific initiating factor, involving the interaction of various genes and signaling pathways. This calcification process is further influenced by a range of factors, including genetic predispositions, environmental exposures, metabolic factors, and hemodynamic considerations. Based on the identification of its biomarkers, potential innovative therapeutic targets are proposed for the treatment of this complex condition. The present article primarily delves into the underlying pathophysiological mechanisms and advancements in diagnostic and therapeutic modalities pertaining to this malady.

Pulse pressure and aortic valve peak velocity and incident heart failure after myocardial infarction: a cohort study

BACKGROUND

Heart failure with preserved ejection fraction is a recognised outcome in patients with myocardial infarction, although heart failure with reduced ejection fraction is more common. Identifying early indicators specific to heart failure with preserved ejection fraction in patients with myocardial infarction could support targeted preventive strategies. This study aimed to determine if pulse pressure and aortic valve peak velocity could serve as early predictors of heart failure with preserved ejection fraction in patients with myocardial infarction.

METHODS

We retrospectively analysed data from 5188 participants in the Atherosclerosis Risk in Communities Study who were free from heart failure at baseline, including 802 individuals with a history of myocardial infarction. Heart failure events were classified as either heart failure with preserved ejection fraction (left ventricular ejection fraction ≥50%) or heart failure with mildly reduced or reduced ejection fraction (left ventricular ejection fraction <50%). Competing risk regression models were used to examine associations of baseline pulse pressure and aortic valve peak velocity with heart failure subtypes.

RESULTS

Over 6 years of follow-up, 217 cases of heart failure with preserved ejection fraction (including 50 in patients with myocardial infarction) and 127 cases of heart failure with mildly reduced or reduced ejection fraction (33 in patients with myocardial infarction) were identified. Among patients with myocardial infarction, a 1-SD increase in pulse pressure was associated with a 1.60-fold higher risk of heart failure with preserved ejection fraction (95% CI 1.30 to 1.97), and a similar association was observed for aortic valve peak velocity (HR: 1.37, 95% CI 1.19 to 1.58). Patients with pulse pressure ≥68 mm Hg had a 3.83-fold higher risk of heart failure with preserved ejection fraction compared with those with lower pulse pressure, and those with aortic valve peak velocity ≥1.4 m/s had a 2.10-fold higher risk compared with those with lower values. Patients with myocardial infarction with two or more risk factors among elevated pulse pressure, aortic valve peak velocity, diabetes and atrial fibrillation had over 16 times the risk of developing heart failure with preserved ejection fraction compared with those without these risk factors (p<0.001).

CONCLUSIONS

Pulse pressure and aortic valve peak velocity are significant predictors of heart failure with preserved ejection fraction in patients with myocardial infarction, suggesting their potential value in early risk stratification. These findings support the use of these markers to guide timely interventions aimed at preventing the progression to heart failure with preserved ejection fraction.

Mechanisms of exercise intolerance in heart failure with preserved ejection fraction (HFpEF)

Exercise intolerance is a well-established symptom of heart failure with preserved ejection fraction (HFpEF) and is associated with impaired quality of life and worse clinical outcomes. Historically attributed to diastolic dysfunction of the left ventricle, exercise intolerance in HFpEF is now known to result not only from diastolic dysfunction, but also from impairments in left ventricular systolic function, left atrial pathology, right ventricular dysfunction, and valvular disease. Disorders of heart rate and rhythm such as chronotropic incompetence and atrial fibrillation have also been implicated in exercise intolerance in this population. Pathologic changes to extra-cardiac organ systems including the respiratory, vascular, hormonal, and skeletal muscle systems are also thought to play a role in exercise impairment. Finally, comorbidities such as obesity, inflammation, and anemia are common and likely contributory in many cases. The role of each of these factors is discussed in this review of exercise intolerance in patients with HFpEF.

Circulating mitochondrial DNA signature in cardiometabolic patients

BACKGROUND

Mitochondrial dysfunction is a hallmark of cardiometabolic diseases. Circulating mitochondrial DNA (mtDNA) profiles could refine risk stratification, but current methods do not account for different fractions of circulating mtDNA. We investigated whether patients with type 2 diabetes and/or heart failure (HF) have a specific signature of the total circulating mtDNA profile, including intracellular and cell-free fractions.

METHODS

We performed a complete clinical assessment, including blood tests, 12-lead ECG and ultrasound at rest and during cardiopulmonary exercise. Ultrasound congestion was defined at rest as inferior vena cava of ≥ 21 mm, lung B-lines ≥ 4, or discontinuous renal venous flow. In fasting whole blood and plasma samples collected at rest, we simultaneously measured the copy number of the cellular and cell-free components of mtDNA by real-time quantitative polymerase chain reaction (qPCR) using custom standards. We calculated the ratio of cell mtDNA to cell-free mtDNA as an index of mitochondrial efficiency.

RESULTS

We enrolled 120 consecutive patients: 50 (42%) with HF and preserved ejection fraction (HFpEF), 40 (33%) with HF and reduced ejection fraction (HFrEF) and 30 (25%) at risk of developing HF; 42/120 (35%) had diabetes. Cell-free mtDNA was increased in patients with HF (with higher levels in HFrEF than HFpEF) and those with diabetes. Cell-free mtDNA was also higher in patients with systemic inflammation (expressed by high-sensitivity C-reactive protein [hs-CRP] ≥ 0.2 mg/dL with neutrophil-lymphocyte ratio [NLR] > 3) and more ultrasound signs of congestion. The cell/cell-free mtDNA ratio showed opposite trends (all p < 0.05), but there were no significant differences in cell mtDNA. Cell-free mtDNA and mtDNA ratio independently predicted the presence of ≥ 2 ultrasound signs of congestion and effort intolerance (peak oxygen consumption < 16 mL/kg/min) at ROC analysis and using multivariable regressions after adjustment for age, sex, hs-CRP, NLR, high-sensitivity Troponin T and NT-proBNP.

CONCLUSIONS

Patients with HF and diabetes have an altered circulating mtDNA signature characterised by higher cell-free mtDNA and lower mtDNA ratio, whereas cellular mtDNA remains unaffected. Cell-free mtDNA and mtDNA ratio are associated with impaired response to exercise, higher systemic inflammation and increased congestion. Circulating mitochondrial profile could be a new biomarker of mitochondrial status in cardiometabolic diseases.

Visceral adiposity: A major mediator of the relationship between epicardial adiposity and cardiorespiratory fitness in adults

BACKGROUND AND AIMS

Epicardial adiposity has been positively associated with visceral adipose tissue (VAT). Few studies have examined the association between cardiorespiratory fitness (CRF) and epicardial adiposity. Furthermore, whether this relationship was independent of VAT remains unexplored. Our purpose was to investigate the contribution of VAT in the relationships between CRF, physical activity (PA) and epicardial adipose tissue (EAT) in asymptomatic women and men.

METHODS AND RESULTS

We examined the associations between EAT and VAT measured by magnetic resonance imaging, CRF measured by cardiopulmonary exercise testing, and PA assessed using pedometers and a 3-day PA journal in 239 apparently healthy adults (43 % women). Participants were compared according to EAT tertiles and CRF level in both sexes. Participants with the highest EAT level presented more VAT (p < 0.001), lower CRF (p < 0.01), and a more deteriorated cardiometabolic health score (p < 0.01) than those with the lowest EAT level. CRF was negatively associated with EAT in both sexes (p < 0.01). No significant relationship was found with PA (p = NS). Stepwise multivariable regression analyses showed that VAT explained most of the variance in EAT in women and men. Mediation analyses confirmed that VAT was a mediator of the association between CRF and EAT in both sexes.

CONCLUSION

In women and men, VAT appears as a major mediator of the association between CRF and EAT thereby suggesting that managing VAT by improving CRF could help in the prevention of cardiometabolic disorders related to excess EAT.

2024 update in heart failure

In the last years, major progress has occurred in heart failure (HF) management. The 2023 ESC focused update of the 2021 HF guidelines introduced new key recommendations based on the results of the last years of science. First, two drugs, sodium-glucose co-transporter-2 (SGLT2) inhibitors and finerenone, a novel nonsteroidal, selective mineralocorticoid receptor antagonist (MRA), are recommended for the prevention of HF in patients with diabetic chronic kidney disease (CKD). Second, SGLT2 inhibitors are now recommended for the treatment of HF across the entire left ventricular ejection fraction spectrum. The benefits of quadruple therapy in patients with HF with reduced ejection fraction (HFrEF) are well established. Its rapid and early up-titration along with a close follow-up with frequent clinical and laboratory re-assessment after an episode of acute HF (the so-called 'high-intensity care' strategy) was associated with better outcomes in the STRONG-HF trial. Patients experiencing an episode of worsening HF might require a fifth drug, vericiguat. In the STEP-HFpEF-DM and STEP-HFpEF trials, semaglutide 2.4 mg once weekly administered for 1 year decreased body weight and significantly improved quality of life and the 6 min walk distance in obese patients with HF with preserved ejection fraction (HFpEF) with or without a history of diabetes. Further data on safety and efficacy, including also hard endpoints, are needed to support the addition of acetazolamide or hydrochlorothiazide to a standard diuretic regimen in patients hospitalized due to acute HF. In the meantime, PUSH-AHF supported the use of natriuresis-guided diuretic therapy. Further options and most recent evidence for the treatment of HF, including specific drugs for cardiomyopathies (i.e., mavacamten in hypertrophic cardiomyopathy and tafamidis in transthyretin cardiac amyloidosis), device therapies, cardiac contractility modulation and percutaneous treatment of valvulopathies, with the recent finding from the TRILUMINATE Pivotal trial, are also reviewed in this article.

Epicardial fat in heart failure-Friend, foe, or bystander

Epicardial adipose tissue (EAT) is a fat depot covering the heart. No physical barrier separates EAT from the myocardium, so EAT can easily affect the underlying cardiac muscle. EAT can participate in the development and progression of heart failure with preserved (HFpEF) and reduced ejection fraction (HFrEF). In healthy humans, excess EAT is associated with impaired cardiac function and worse outcomes. In HFpEF, this trend continues: EAT amount is usually increased, and excess EAT correlates with worse function/outcomes. However, in HFrEF, the opposite is true: reduced EAT amount correlates with worse cardiac function/outcomes. Surprisingly, although EAT has beneficial effects on cardiac function, it aggravates ventricular arrhythmias. Here, we dissect these phenomena, trying to explain these paradoxical findings to find a target for novel heart failure therapies aimed at EAT rather than the myocardium itself. However, the success of this approach depends on a thorough understanding of interactions between EAT and the myocardium.

Sex Differences in Aortic Stenosis: From the Pathophysiology to the Intervention, Current Challenges, and Future Perspectives

Calcific aortic stenosis (AS) is a major cause of morbidity and mortality in high-income countries. AS presents sex-specific features impacting pathophysiology, outcomes, and management strategies. In women, AS often manifests with a high valvular fibrotic burden, small valvular annuli, concentric left ventricular (LV) remodeling/hypertrophy, and, frequently, supernormal LV ejection fraction coupled with diastolic dysfunction. Paradoxical low-flow low-gradient AS epitomizes these traits, posing significant challenges post-aortic valve replacement due to limited positive remodeling and significant risk of patient-prosthesis mismatch. Conversely, men present more commonly with LV dilatation and dysfunction, indicating the phenotype of classical low-flow low-gradient AS, i.e., with decreased LV ejection fraction. However, these distinctions have not been fully incorporated into guidelines for AS management. The only treatment for AS is aortic valve replacement; women are frequently referred late, leading to increased heart damage caused by AS. Therefore, it is important to reassess surgical planning and timing to minimize irreversible cardiac damage in women. The integrity and the consideration of sex differences in the management of AS is critical. Further research, including sufficient representation of women, is needed to investigate these differences and to develop individualized, sex-specific management strategies.

Heart Failure With Preserved Ejection Fraction and Frailty: From Young to Superaged Coexisting HFpEF and Frailty

Being commonly diagnosed in elderly women and associated with comorbidities as well as ageing-related cardio-vascular changes, heart failure with preserved ejection fraction (HFpEF) has been recently considered as a distinct cardiogeriatric syndrome. Frailty is another frequent geriatric syndrome. HFpEF and frailty share common underlying mechanisms, often co-exist, and represent each other's risk factors. A threshold of 65 years old is usually used to screen patients for both frailty and HFpEF in research and clinical settings. However, both HFpEF and frailty are very heterogenous conditions that may develop at younger ages. In this review we aim to provide a broader overview on the coexistence of HFpEF and frailty throughout the lifetime. We hypothesize that HFpEF and frailty patients' profiles (young, elderly, superaged) represent a continuum of the common ageing process modified by cumulative exposure to risk factors resulting to a presentation of HFpEF and frailty at different ages. We believe, that suggested approach might stimulate assessment of frailty in HFpEF assessment and vice versa regardless of age and early implementation of targeted interventions. Future studies of pathophysiology, clinical features, and outcomes of frailty in HFpEF by age are needed.

mPAP/CO Slope and Oxygen Uptake Add Prognostic Value in Aortic Stenosis

BACKGROUND

Recent guidelines redefined exercise pulmonary hypertension as a mean pulmonary artery pressure/cardiac output (mPAP/CO) slope >3 mm Hg·L-1·min-1. A peak systolic pulmonary artery pressure >60 mm Hg during exercise has been associated with an increased risk of cardiovascular death, heart failure rehospitalization, and aortic valve replacement in aortic valve stenosis. The prognostic value of the mPAP/CO slope in aortic valve stenosis remains unknown.

METHODS

In this prospective cohort study, consecutive patients (n=143; age, 73±11 years) with an aortic valve area ≤1.5 cm2 underwent cardiopulmonary exercise testing with echocardiography. They were subsequently evaluated for the occurrence of cardiovascular events (ie, cardiovascular death, heart failure hospitalization, new-onset atrial fibrillation, and aortic valve replacement) during a follow-up period of 1 year. Findings were externally validated (validation cohort, n=141).

RESULTS

One cardiovascular death, 32 aortic valve replacements, 9 new-onset atrial fibrillation episodes, and 4 heart failure hospitalizations occurred in the derivation cohort, whereas 5 cardiovascular deaths, 32 aortic valve replacements, 1 new-onset atrial fibrillation episode, and 10 heart failure hospitalizations were observed in the validation cohort. Peak aortic velocity (odds ratio [OR] per SD, 1.48; P=0.036), indexed left atrial volume (OR per SD, 2.15; P=0.001), E/e' at rest (OR per SD, 1.61; P=0.012), mPAP/CO slope (OR per SD, 2.01; P=0.002), and age-, sex-, and height-based predicted peak exercise oxygen uptake (OR per SD, 0.59; P=0.007) were independently associated with cardiovascular events at 1 year, whereas peak systolic pulmonary artery pressure was not (OR per SD, 1.28; P=0.219). Peak Vo2 (percent) and mPAP/CO slope provided incremental prognostic value in addition to indexed left atrial volume and aortic valve area (P<0.001). These results were confirmed in the validation cohort.

CONCLUSIONS

In moderate and severe aortic valve stenosis, mPAP/CO slope and percent-predicted peak Vo2 were independent predictors of cardiovascular events, whereas peak systolic pulmonary artery pressure was not. In addition to aortic valve area and indexed left atrial volume, percent-predicted peak Vo2 and mPAP/CO slope cumulatively improved risk stratification.

Immune response following transcatheter aortic valve procedure

Aortic valve stenosis is the most common type of heart valve disease in the United States and Europe and calcific aortic stenosis (AS) affects 2-7% of people aged 65 years and older. Aortic valve replacement (AVR) is the only effective treatment for individuals with this condition. Transcatheter Aortic Valve Replacement (TAVR) has been widely accepted as a minimally invasive therapeutic approach for addressing symptomatic AS in patients who are considered to have a high risk for traditional surgical intervention. TAVR procedure may have a paradoxical effect on the immune system and inflammatory status. A major portion of these immune responses is regulated by activating or inhibiting inflammatory monocytes and the complement system with subsequent changes in inflammatory cytokines. TAVR has the potential to induce various concurrent exposures, including disruption of the native valve, hemodynamic changes, antigenicity of the bioprosthesis, and vascular damage, which finally lead to the development of inflammation. On the other hand, it is important to acknowledge that TAVR may also have anti-inflammatory effects by helping in the resolution of stenosis.The inflammation and immune response following TAVR are complex processes that significantly impact procedural outcomes and patient well-being. Understanding the underlying mechanisms, identifying biomarkers of inflammation, and exploring therapeutic interventions to modulate these responses are crucial for optimizing TAVR outcomes. Further research is warranted to elucidate the precise immunological dynamics and develop tailored strategies to attenuate inflammation and enhance post-TAVR healing while minimizing complications.