The role of sacubitril/valsartan in abnormal renal function patients combined with heart failure: a meta-analysis and systematic analysis

AIMS

This study aimed to investigate the efficacy and safety of sacubitril/valsartan in abnormal renal function (eGFR < 60 ml/min/1.73m2) patients combined with heart failure based on randomized controlled trials (RCTs) and observational studies.

METHODS

The Embase, PubMed and the Cochrane Library were searched for relevant studies from inception to December 2023. Dichotomous variables were described as event counts with the odds ratio (OR) and 95% confidence interval (CI) values. Continuous variables were expressed as mean standard deviation (SD) with 95% CIs.

RESULTS

A total of 6 RCTs and 8 observational studies were included, involving 17335 eGFR below 60 ml/min/1.73m2 patients combined with heart failure. In terms of efficacy, we analyzed the incidence of cardiovascular events and found that sacubitril/valsartan significantly reduced the risk of cardiovascular death or heart failure hospitalization in chronic kidney disease (CKD) stages 3-5 patients with heart failure (OR: 0.65, 95%CI: 0.54-0.78). Moreover, sacubitril/valsartan prevented the serum creatinine elevation (OR: 0.81, 95%CI: 0.68-0.95), the eGFR decline (OR: 0.83, 95% CI: 0.73-0.95) and the development of end-stage renal disease in this population (OR:0.73, 95%CI:0.60-0.89). As for safety outcomes, we did not find that the rate of hyperkalemia (OR:1.31, 95%CI:0.79-2.17) and hypotension (OR:1.57, 95%CI:0.94-2.62) were increased in sacubitril/valsartan group among CKD stages 3-5 patients with heart failure.

CONCLUSIONS

Our meta-analysis proves that sacubitril/valsartan has a favorable effect on cardiac function without obvious risk of adverse events in abnormal renal function patients combined with heart failure, indicating that sacubitril/valsartan has the potential to become perspective treatment for these patients.

Factors associated with risk analysis for asymptomatic left ventricular diastolic dysfunction in nondialysis patients with chronic kidney disease

Heart failure (HF) constitutes a major determinant of outcome in chronic kidney disease (CKD) patients. The main pattern of HF in CKD patients is preserved ejection fraction (HFpEF), and left ventricular diastolic dysfunction (LVDD) is a frequent pathophysiological mechanism and specific preclinical manifestation of HFpEF. Therefore, exploring and intervention of the factors associated with risk for LVDD is of great importance in reducing the morbidity and mortality of cardiovascular disease (CVD) complications in CKD patients. We designed this retrospective cross-sectional study to collect clinical and echocardiographic data from 339 nondialysis CKD patients without obvious symptoms of HF to analyze the proportion of asymptomatic left ventricular diastolic dysfunction (ALVDD) and its related factors associated with risk by multivariate logistic regression analysis. Among the 339 nondialysis CKD patients, 92.04% had ALVDD. With the progression of CKD stage, the proportion of ALVDD gradually increased. The multivariate logistic regression analysis revealed that increased age (OR 1.237; 95% confidence interval (CI) 1.108-1.381, per year), diabetic nephropathy (DN) and hypertensive nephropathy (HTN) (OR 25.000; 95% CI 1.355-48.645, DN and HTN vs chronic interstitial nephritis), progression of CKD stage (OR 2.785; 95% CI 1.228-6.315, per stage), increased mean arterial pressure (OR 1.154; 95% CI 1.051-1.268, per mmHg), increased urinary protein (OR 2.825; 95% CI 1.484-5.405, per g/24 h), and low blood calcium (OR 0.072; 95% CI 0.006-0.859, per mmol/L) were factors associated with risk for ALVDD in nondialysis CKD patients after adjusting for other confounding factors. Therefore, dynamic monitoring of these factors associated with risk, timely diagnosis and treatment of ALVDD can delay the progression to symptomatic HF, which is of great importance for reducing CVD mortality, and improving the prognosis and quality of life in CKD patients.

Prognostic value of plasma secretoneurin concentration in patients with heart failure with reduced ejection fraction in one-year follow-up

BACKGROUND

This is the first study to examine the clinical utility of measuring plasma secretoneurin (SN) levels in patients with heart failure with reduced ejection fraction (HFrEF), as a predictor of unplanned hospitalization, and all-cause mortality independently, and as a composite endpoint at one-year follow-up.

METHODS

The study group includes 124 caucasian patients in New York Heart Association (NYHA) classes II to IV. Plasma SN concentrations were statistically analyzed in relation to sex, age, BMI, etiology of HFrEF, pharmacotherapy, clinical, laboratory and echocardiographic parameters. Samples were collected within 24 h of admission to the hospital.

KEY RESULTS

In the 12-month follow-up, high SN levels were noted for all three endpoints.

CONCLUSIONS

SN positively correlates with HF severity measured by NYHA classes and proves to be a useful prognostic parameter in predicting unplanned hospitalizations and all-cause mortality among patients with HFrEF. Patients with high SN levels may benefit from systematic follow-up and may be candidates for more aggressive treatment.

Machine learning model and nomogram to predict the risk of heart failure hospitalization in peritoneal dialysis patients

INTRODUCTION

The study presented here aimed to establish a predictive model for heart failure (HF) and all-cause mortality in peritoneal dialysis (PD) patients with machine learning (ML) algorithm.

METHODS

We retrospectively included 1006 patients who initiated PD from 2010 to 2016. XGBoost, random forest (RF), and AdaBoost were used to train models for assessing risk for 1-year and 5-year HF hospitalization and mortality. The performance was validated using fivefold cross-validation. The optimal ML algorithm was used to construct the models to predictive the risk of the HF and all-cause mortality. The prediction performance of ML methods and Cox regression was compared.

RESULTS

Over a median follow-up of 49 months. Two hundred and ninety-eight patients developed HF required hospitalization; 199 patients died during the follow-up. The RF model (AUC = 0.853) was the best performing model for predicting HF, and the XGBoost model (AUC = 0.871) was the best model for predicting mortality. Baseline moderate or severe renal disease, systolic blood pressure (SBP), body mass index (BMI), age, Charlson Comorbidity Index (CCI) score were strongly associated with HF hospitalization, whereas age, CCI score, creatinine, age, high-density lipoprotein cholesterol (HDL-C), total cholesterol, baseline estimated glomerular filtration rate (eGFR) were the most significant predictors of mortality. For all the above endpoints, the ML models demonstrated better discrimination than Cox regression.

CONCLUSIONS

We developed and validated a novel method to predict the risk factors of HF and all-cause mortality that integrates readily available clinical, laboratory, and electrocardiographic variables to predict the risk of HF among PD patients.

Neonatal heart transplantation in the United States: Trends and outcomes

BACKGROUND

Heart transplantation in the neonatal period is associated with excellent survival. However, outcomes data are scant and have been obtained primarily from two single-center reports within the United States. We sought to analyze the outcomes of all neonatal heart transplants performed in the United States using the United Network for Organ Sharing (UNOS) dataset.

METHODS

The UNOS dataset was queried for patients who underwent infant heart transplantation from 1987 to 2021. Patients were divided into two groups based on age - neonates (<=31 days), and older infants (32 days-365 days). Demographic and clinical characteristics were analyzed and compared, along with follow up survival data.

RESULTS

Overall, 474 newborns have undergone heart transplantation in the United States since 1987. Freedom from death or re-transplantation for neonates was 63.5%, 58.8% and 51.6% at 5, 10, and 20 years, respectively. Patients in the newborn group had lower unadjusted survival compared to older infants (p < .001), but conditional 1-year survival was higher in neonates (p = .03). On multivariable analysis, there was no significant difference in survival between the two age groups (p = .43). Black race, congenital heart disease diagnosis, earlier surgical era, and preoperative mechanical circulatory support use were associated with lower survival among infant transplants (p < .05).

CONCLUSIONS

Neonatal heart transplantation is associated with favorable long-term clinical outcomes. Neonates do not have a significant survival advantage over older infants. Widespread applicability is limited by the small number of available donors. Efforts to expand the donor pool to include non-standard donor populations ought to be considered.

Association between greenery and health indicators in urban patients with symptomatic heart failure: a retrospective cohort study in Lithuania

Urban green spaces benefit physical, mental health, and reduses the risk of cardiovascular disease. A study in Kaunas, Lithuania collected health data from 100 patients with symptomatic heart failure (HF) during 2006-2009. Residential greenness was measured by the normalized difference vegetation index (NDVI). We assessed the impact of greenness on health indicators and on changes in health markers after 6 months. Higher greenness levels based on the NDVI 1-km radius were related to higher mean values of heart rate (HR) and ejection fraction and lower left ventricular (LV) end-diastolic diameter index (LV EDDI), LV end-systolic volume (ESV), left atrium size (LAS), and right atrium size (RAS) at baseline. After 6 months, a decrease in DBP and HR and an improvement in spiroergometric parameters were associated with exposure to high levels of greenness.  The long-term rehabilitation group experienced significant changes in spiroergometric indicators. The results confirm that the greenness of the residential environment can improve health indicators in patients with HF.

Impact of empagliflozin on insulin needs in patients with heart failure and diabetes: An EMPEROR-Pooled analysis

AIM

To assess the effect of empagliflozin on patients with comorbid heart failure (HF) and diabetes with or without baseline insulin, and to study the impact of empagliflozin on insulin requirements over time.

MATERIALS AND METHODS

We performed a post-hoc analysis of pooled patient-level data from two cardiovascular outcomes trials of empagliflozin in HF (EMPEROR-Reduced and EMPEROR-Preserved trials). We undertook a subgroup analysis stratified by baseline insulin use, including all patients with diabetes. The studied endpoints included the primary composite endpoint of first hospitalization for HF or cardiovascular death, rate of decline of estimated glomerular filtration rate, composite renal outcome and rates of sustained insulin initiation.

RESULTS

Among 4794 patients with diabetes, 1333 (658 in empagliflozin, 675 in placebo) were using insulin at baseline. The treatment effect of empagliflozin on the primary endpoint was consistent irrespective of insulin use [no insulin, hazard ratio 0.74, 95% confidence interval (CI) 0.63-0.86; using insulin, hazard ratio 0.81, 95% CI 0.66-1.00, pinteraction = .49], as was the effect on the rate of decline of the estimated glomerular filtration rate (pinteraction = .75). There was no effect of empagliflozin on the composite renal outcome in patients using or not using insulin (pinteraction = .30). Among patients not using insulin at baseline, those randomized to empagliflozin initiated insulin less frequently throughout the follow-up period compared with those receiving placebo (2.6% vs. 3.8%, odds ratio 0.66, 95% CI 0.50-0.88).

CONCLUSIONS

Empagliflozin exerts a consistent benefit on cardiovascular outcomes and renal function decline, irrespective of baseline insulin use, and reduces the need for sustained insulin initiation in patients with HF and diabetes.

R2R01: A long-acting single-chain peptide agonist of RXFP1 for renal and cardiovascular diseases

BACKGROUND

The therapeutic potential of relaxin for heart failure and renal disease in clinical trials is hampered by the short half-life of serelaxin. Optimization of fatty acid-acetylated single-chain peptide analogues of relaxin culminated in the design and synthesis of R2R01, a potent and selective RXFP1 agonist with subcutaneous bioavailability and extended half-life.

EXPERIMENTAL APPROACH

Cellular assays and pharmacological models of RXFP1 activation were used to validate the potency and selectivity of R2R01. Increased renal blood flow was used as a translational marker of R2R01 activity. Human mastocytes (LAD2 cells) were used to study potential pseudo-allergic reactions and CD4+ T-cells to study immunogenicity. The pharmacokinetics of R2R01 were characterized in rats and minipigs.

KEY RESULTS

In vitro, R2R01 had comparable potency and efficacy to relaxin as an agonist for human RXFP1. In vivo, subcutaneous administration of R2R01 increased heart rate and renal blood flow in normotensive and hypertensive rat and did not show evidence of tachyphylaxis. R2R01 also increased nipple length in rats, used as a chronic model of RXFP1 engagement. Pharmacokinetic studies showed that R2R01 has a significantly extended terminal half-life. The in vitro assays with LAD2 cells and CD4+ T-cells showed that R2R01 had low potential for pseudo-allergic and immunogenic reactions, respectively.

CONCLUSION AND IMPLICATIONS

R2R01 is a potent RXFP1 agonist with an extended half-life that increases renal blood flow in various settings including normotensive and hypertensive conditions. The preclinical efficacy and safety data supported clinical development of R2R01 as a potential new therapy for renal and cardiovascular diseases.

A novel approach to accurately measuring the burden of hospitalisations for cardiovascular disease in people with diabetes: A pilot study

AIM

To determine the reliability of hospital discharge codes for heart failure (HF), acute myocardial infarction (AMI) and stroke compared with adjudicated diagnosis, and to pilot a scalable approach to adjudicate records on a population-based sample.

METHODS

A population-based sample of 685 people with diabetes admitted (1274 admissions) to one of three Australian hospitals during 2018-2020 were randomly selected for this study. All medical records were reviewed and adjudicated.

RESULTS

Cardiovascular diseases were the most common primary reason for hospitalisation in people with diabetes, accounting for ~17% (215/1274) of all hospitalisations, with HF as the leading cause. ICD-10 codes substantially underestimated HF prevalence and had the lowest agreement with the adjudicated diagnosis of HF (Kappa = 0.81), compared with AMI and stroke (Kappa ≥ 0.91). While ICD-10 codes provided suboptimal sensitivity (72%) for HF, the performance was better for AMI (sensitivity 84%; specificity 100%) and stroke (sensitivity 85%; specificity 100%). A novel approach to screen possible HF cases only required adjudicating 8% (105/1274) of records, correctly identified 78/81 of HF admissions and yielded 96% sensitivity and 98% specificity.

CONCLUSIONS

While ICD-10 codes appear reliable for AMI or stroke, a more complex diagnosis such as HF benefits from a two-stage process to screen for suspected HF cases that need adjudicating. The next step is to validate this novel approach on large multi-centre studies in diabetes.

Significant Mitral Regurgitation After Permanent Right Ventricular Pacemaker Implantation: Prognostic Implications

The underlying mechanisms leading to the development of mitral regurgitation (MR) after right ventricular (RV) pacemaker (PM) implantation and its prognostic value have yet to be fully understood. The purpose of this study was to evaluate the prevalence and clinical variables associated with the development of MR after RV pacing and its association with outcomes. A total of 451 patients (mean age 69 ± 15 years, 61% male) who underwent de novo RV PM implantation were included. The development of significant MR, defined as ≥moderate from mild or none/trace at baseline, occurred in 131 (29%) patients at a median of 2.4 years (interquartile range: 1.0 to 3.8 years) after PM implantation. Multivariate logistic regression analysis demonstrated that implantation of a single-chamber PM, left ventricular end-systolic volume index, and the presence of mild MR (vs no MR) at baseline were independently associated with the development of significant MR post-implant. Cardiac events, defined as the composite of all-cause mortality or heart failure hospitalization, occurred in 143 patients (31.7%) during a median follow-up of 5.4 years (interquartile range: 3.0 to 8.1 years). Multivariate Cox regression analysis demonstrated that the development of significant MR was independently related to the occurrence of cardiac events. In conclusion, the development of significant MR after PM implantation is seen in about one-third of recipients and is independently associated with adverse cardiac events.

Risk of Major Adverse Cardiovascular Events After Emergency Department Visits for Hypertensive Urgency

BACKGROUND

Chronic hypertension is an established long-term risk factor for major adverse cardiovascular events (MACEs). However, little is known about short-term MACE risk after hypertensive urgency, defined as an episode of acute severe hypertension without evidence of target-organ damage. We sought to evaluate the short-term risk of MACE after an emergency department (ED) visit for hypertensive urgency resulting in discharge to home.

METHODS

We performed a case-crossover study using deidentified administrative claims data. Our case periods were 1-week intervals from 0 to 12 weeks before hospitalization for MACE. We compared ED visits for hypertensive urgency during these case periods versus equivalent control periods 1 year earlier. Hypertensive urgency and MACE components were all ascertained using previously validated International Classification of Diseases, Tenth Revision Clinical Modification codes. We used McNemar test for matched data to calculate risk ratios.

RESULTS

Among 2 225 722 patients with MACE, 1 893 401 (85.1%) had a prior diagnosis of hypertension. There were 4644 (0.2%) patients who had at least 1 ED visit for hypertensive urgency during the 12 weeks preceding their MACE hospitalization. An ED visit for hypertensive urgency was significantly more common in the first week before MACE compared with the same chronological week 1 year earlier (risk ratio, 3.5 [95% CI, 2.9-4.2]). The association between hypertensive urgency and MACE decreased in magnitude with increasing temporal distance from MACE and was no longer significant by 11 weeks before MACE (risk ratio, 1.2 [95% CI, 0.99-1.6]).

CONCLUSIONS

ED visits for hypertensive urgency were associated with a substantially increased short-term risk of subsequent MACE.

Association between atrial fibrillation and heart failure patient reported outcomes across the ejection fraction spectrum

BACKGROUND

Atrial fibrillation (AF) is common in patients with heart failure (HF) and is associated with worse clinical outcomes. We evaluated the relationship between AF and longitudinal changes in health-related quality of life (HRQoL) measured by Kansas City Cardiomyopathy Questionnaire (KCCQ) in both HF with preserved (HFpEF) and reduced ejection fraction (HFrEF).

METHODS

This is a post-hoc analysis of the TOPCAT and HF-ACTION trials. The effect of AF on KCCQ overall summary scores (OSS), in both trials, was examined using a mixed effects regression model. Patients were divided into 3 groups according to AF status at baseline: patients with a history of AF but no AF detected on ECG at enrollment (Hx AF group), patients with history of AF and AF detected on ECG at enrollment (ECG AF group) and patients with post-randomization new-onset AF (New AF group).

RESULTS

In TOPCAT, among 1,710 patients with KCCQ data available, AF was associated with a significantly lower KCCQ-OSS (-3.98; 95% CI -7.21: -0.74) at 48 months, with a significant AF status by time interaction (P = .03). In HF-ACTION, among 1,814 patients with available KCCQ data, AF was associated with a significantly lower KCCQ-OSS (-3.67; 95% CI -6.21: -1.41) at 24 months but there was no significant AF status by time interaction. In both trials, the type of AF was not associated with significant changes in KCCQ-OSS score.

CONCLUSION

Ιn patients with both HFpEF and HFrEF, AF was independently associated with worse HRQoL measured by KCCQ.

Possible Role of Gut Microbiota Alterations in Myocardial Fibrosis and Burden of Heart Failure in Hypertensive Heart Disease

Epidemiological studies have revealed that hypertensive heart disease is a major risk factor for heart failure, and its heart failure burden is growing rapidly. The need to act in the face of this threat requires first an understanding of the multifactorial origin of hypertensive heart disease and second an exploration of new mechanistic pathways involved in myocardial alterations critically involved in cardiac dysfunction and failure (eg, myocardial interstitial fibrosis). Increasing evidence shows that alterations of gut microbiota composition and function (ie, dysbiosis) leading to changes in microbiota-derived metabolites and impairment of the gut barrier and immune functions may be involved in blood pressure elevation and hypertensive organ damage. In this review, we highlight recent advances in the potential contribution of gut microbiota alterations to myocardial interstitial fibrosis in hypertensive heart disease through blood pressure-dependent and blood pressure-independent mechanisms. Achievements in this field should open a new path for more comprehensive treatment of myocardial interstitial fibrosis in hypertensive heart disease and, thus, for the prevention of heart failure.

32-year-old Traumatic Arteriovenous Fistula Presenting With Leg Ulcer and High-output Heart Failure

Traumatic arteriovenous fistula (AVF) is not a common disorder, and dermatological signs and heart failure caused by AVF are rarely reported. We present the case of a 55-year-old woman who was referred for congestive heart failure symptoms. Echocardiography revealed preserved left ventricular ejection fraction. Due to edema of the right leg with a long-standing leg ulcer and palpable femoral thrill, duplex ultrasonography was performed. It showed an AVF between the right superficial femoral artery (SFA) and the right femoral vein (FV). The patient recalled a 32-year-old gunshot injury that was not medically treated. After the diagnosis of AVF she was referred to a surgeon for an AVF ligation, with subsequent resolution of her symptoms. The differential diagnosis of leg ulcer with leg edema should include the possibility of AVF as a cause.

Safety and Outcomes of Mechanical Thrombectomy in Acute Ischemic Stroke Attributable to Cardiological Diseases: A Scoping Review

There is limited evidence on the outcomes and safety of mechanical thrombectomy (MT) among patients with acute ischemic stroke (AIS) in the context of cardiac diseases. Our study reviews MT in AIS within the context of cardiac diseases, aiming to identify existing and emerging needs and gaps. PubMed and Scopus were searched until December 31, 2023, using a combination of cardiological diseases and "mechanical thrombectomy" or "endovascular treatment" as keywords. Study design included case reports/series, observational studies, randomized clinical trials, and meta-analyses/systematic reviews. We identified 943 articles, of which 130 were included in the review. Results were categorized according to the cardiac conditions. MT shows significant benefits in patients with atrial fibrillation (n=139) but lacks data for stroke occurring after percutaneous coronary intervention (n=2) or transcatheter aortic valve implantation (n=5). MT is beneficial in AIS attributable to infective endocarditis (n=34), although functional benefit may be limited. Controversy surrounds the functional outcomes and mortality of patients with AIS with heart failure undergoing MT (n=11). Despite technical challenges, MT appears feasible in aortic dissection cases (n=4), and in patients with left ventricular assist device or total artificial heart (n=10). Data on AIS attributable to congenital heart disease (n=4) primarily focus on pediatric cases requiring technical modifications. Treatment outcomes of MT in patients with cardiac tumors (n=8) vary because of clot consistency differences. After cardiac surgery stroke, MT may improve outcomes with early intervention (n=13). Available data outline the feasibility of MT in patients with AIS attributable to large-vessel occlusion in the context of cardiac diseases.

Development of a quality of life measure for left ventricular assist device recipients using a mixed methods approach

BACKGROUND

Left ventricular assist device (LVAD) recipients report symptom improvement but find adjusting to life with the LVAD challenging. These challenges are unique, and existing patient-reported outcome measures (PROMs) do not reflect their experiences. This study aimed to develop a culturally relevant quality of life PROM for use with LVAD recipients in future research, design evolutions and clinical practice.

METHODS

A three-stage mixed-methods approach was used to develop a PROM: stage 1 included group concept mapping (GCM); stage 2 semi-structured qualitative interviews were conducted with 11 LVAD recipients and 10 clinicians, and a questionnaire was developed using a conceptual framework; and stage 3 used exploratory psychometric analysis of the PROM data using Rasch measurement theory. This paper presents stages 2 and 3.

RESULTS

The conceptual framework consisted of four key concepts, including general health, life with the LVAD, equipment and clothing and emotional impact. Statements from interviews and GCM were used to create items for the LVAD quality of life (LVAD-QoL). Cognitive interviews tested face validity and participant comprehension. Forty-nine participants were recruited from three UK transplant centres. PROM data were collected and analysed using Rasch analysis. Four items displayed misfit; dependency between item sets was the biggest issue (57/485 pairwise differences). After restructuring and dealing with item misfit, the LVAD-QoL conformed to the Rasch model, supporting the psychometric properties and quality of the LVAD-QoL.

CONCLUSIONS

Using a mixed-methods approach ensured the development of a robust and psychometrically sound tool for research, design evolution and clinical practice with LVAD recipients.

Dyadic relationships between informal caregivers and older adults with chronic heart failure: A systematic review and meta-synthesis

AIM

To synthesise the qualitative evidence on dyadic relationships between informal caregivers (ICs) and older adults with chronic heart failure (HF).

METHODS AND RESULTS

A systematic review and meta-synthesis were conducted. Eight databases were searched for English peer-reviewed studies and grey literature published from inception to 27 February 2024. Qualitative and mixed-method studies involving older adults ≥ 55 years old with chronic HF and discussing patient-caregiver relationships in community settings were included. Data were synthesised using Sandelowski and Barroso's 2-step framework. A meta-summary was developed using thematic analysis, and findings were synthesised using the Theory of Dyadic Illness Management. Twenty-four studies from 2008 to 2024 were included (n = 580 participants). The meta-summary consisted of four themes and nine subthemes: (1) Characteristics of dyad relationships, (2) How both parts of the dyad care for each other, (3) Chronic HF and dyad relationships, (4) Knowledge of managing chronic HF. These were reorganised into the meta-synthesis: dyadic appraisal, dyadic management behaviours, dyadic health, contextual factors affecting dyadic relationships and management behaviours, and illness management as a dyadic phenomenon.

CONCLUSION

Investigating relationship dynamics and their impact on dyads and chronic HF self-care is vital. Where possible, healthcare providers should prioritise dyadic care when caregivers are involved and deliver individualised care to improve patient and caregiver outcomes. Assessing and optimising dyadic relations, addressing individual perceptions and needs as part of clinical care, and before implementing self-care interventions in research may help ensure that self-care is appropriately tailored and would not be hindered by relationship conflicts.

The Ubiquitin Ligase RBX2/SAG Regulates Mitochondrial Ubiquitination and Mitophagy

BACKGROUND

Clearance of damaged mitochondria via mitophagy is crucial for cellular homeostasis. Apart from Parkin, little is known about additional Ub (ubiquitin) ligases that mediate mitochondrial ubiquitination and turnover, particularly in highly metabolically active organs such as the heart.

METHODS

In this study, we have combined in silico analysis and biochemical assay to identify CRL (cullin-RING ligase) 5 as a mitochondrial Ub ligase. We generated cardiomyocytes and mice lacking RBX2 (RING-box protein 2; also known as SAG [sensitive to apoptosis gene]), a catalytic subunit of CRL5, to understand the effects of RBX2 depletion on mitochondrial ubiquitination, mitophagy, and cardiac function. We also performed proteomics analysis and RNA-sequencing analysis to define the impact of loss of RBX2 on the proteome and transcriptome.

RESULTS

RBX2 and CUL (cullin) 5, 2 core components of CRL5, localize to mitochondria. Depletion of RBX2 inhibited mitochondrial ubiquitination and turnover, impaired mitochondrial membrane potential and respiration, increased cardiomyocyte cell death, and has a global impact on the mitochondrial proteome. In vivo, deletion of the Rbx2 gene in adult mouse hearts suppressed mitophagic activity, provoked accumulation of damaged mitochondria in the myocardium, and disrupted myocardial metabolism, leading to the rapid development of dilated cardiomyopathy and heart failure. Similarly, ablation of RBX2 in the developing heart resulted in dilated cardiomyopathy and heart failure. The action of RBX2 in mitochondria is not dependent on Parkin, and Parkin gene deletion had no impact on the onset and progression of cardiomyopathy in RBX2-deficient hearts. Furthermore, RBX2 controls the stability of PINK1 in mitochondria.

CONCLUSIONS

These findings identify RBX2-CRL5 as a mitochondrial Ub ligase that regulates mitophagy and cardiac homeostasis in a Parkin-independent, PINK1-dependent manner.

Association Between Serum Albumin and the Length of Hospital Stay Among Patients With Acute Heart Failure

Introduction: Albumin plays a vital role in improving osmotic pressure and hemodynamics. A lower serum albumin level may cause pulmonary congestion and edema and contribute to myocardial dysfunction, diuresis resistance, and fluid retention in acute heart failure. Hypothesis: We hypothesized that AHF patients with normal serum albumin have shorter hospital stays. Methods: Using Electronic Medical Records, patients admitted from May 2020 through May 2021 aged >18, ICD-10, and positive Framingham Heart Failure Diagnostic Criteria were included. We excluded patients without albumin records and eGFRs less than 30 mL/min/1.73 m2. Prolonged hospitalization was defined as >8 days of hospitalization. Results: During index emergency department visits, patients were symptomatic (New York Heart Association), aged median of 70 years (Interquartile range (IQR) 18), 59% (n = 103) were male, predominantly White (73%, n = 128), and had a high Charleston Comorbidity index score [5, IQR (4-7)]. Nearly one-fourth (23%, n = 41) of the patients had <3.5 g/dL albumin levels. The median length of hospital stay was eight days (IQR of 11). Comparing differences between lengths of hospital stays (<8 vs. >8 days), there was different serum albumin (3.9 + 0.48 vs. 3.6 + 0.53, p < .001) and left ventricular ejection fraction (45% (range 26-63) versus 30% (range 24-48), p = .004). An increased serum albumin decreased prolonged hospitalization (odds ratio (OR), 0.28; 95% confidence interval (CI), 0.14-0.55, p = <0.001). Patients in the lower albumin group had higher NT-proBNP (median: 8521 (range 2025-9134) versus 5147 (range 2966-14,795) pg/ml, p = .007) and delay in administering intravenous diuretics (391 (167-964) minutes versus 271 (range 157-533) minutes, p = .02). Conclusion: Hypoalbuminemia is strongly associated with prolonged hospitalization. Timely and effective diuretic therapy may reduce hospital stay durations, particularly with albumin supplementation.

Endovascular transplantation of mRNA-enhanced mesenchymal stromal cells results in superior therapeutic protein expression in swine heart

Heart failure has a poor prognosis and no curative treatment exists. Clinical trials are investigating gene- and cell-based therapies to improve cardiac function. The safe and efficient delivery of these therapies to solid organs is challenging. Herein, we demonstrate the feasibility of using an endovascular intramyocardial delivery approach to safely administer mRNA drug products and perform cell transplantation procedures in swine. Using a trans-vessel wall (TW) device, we delivered chemically modified mRNAs (modRNA) and mRNA-enhanced mesenchymal stromal cells expressing vascular endothelial growth factor A (VEGF-A) directly to the heart. We monitored and mapped the cellular distribution, protein expression, and safety tolerability of such an approach. The delivery of modRNA-enhanced cells via the TW device with different flow rates and cell concentrations marginally affect cell viability and protein expression in situ. Implanted cells were found within the myocardium for at least 3 days following administration, without the use of immunomodulation and minimal impact on tissue integrity. Finally, we could increase the protein expression of VEGF-A over 500-fold in the heart using a cell-mediated modRNA delivery system compared with modRNA delivered in saline solution. Ultimately, this method paves the way for future research to pioneer new treatments for cardiac disease.

Therapeutic Inhibition of LincRNA-p21 Protects Against Cardiac Hypertrophy

BACKGROUND

Cardiac hypertrophy is an adaptive response to pressure overload aimed at maintaining cardiac function. However, prolonged hypertrophy significantly increases the risk of maladaptive cardiac remodeling and heart failure. Recent studies have implicated long noncoding RNAs in cardiac hypertrophy and cardiomyopathy, but their significance and mechanism(s) of action are not well understood.

METHODS

We measured lincRNA-p21 RNA and H3K27ac levels in the hearts of dilated cardiomyopathy patients. We assessed the functional role of lincRNA-p21 in basal and surgical pressure-overload conditions using loss-of-function mice. Genome-wide transcriptome analysis revealed dysregulated genes and pathways. We labeled proteins in proximity to full-length lincRNA-p21 using a novel BioID2-based system. We immunoprecipitated lincRNA-p21-interacting proteins and performed cell fractionation, ChIP-seq (chromatin immunoprecipitation followed by sequencing), and co-immunoprecipitation to investigate molecular interactions and underlying mechanisms. We used GapmeR antisense oligonucleotides to evaluate the therapeutic potential of lincRNA-p21 inhibition in cardiac hypertrophy and associated heart failure.

RESULTS

lincRNA-p21 was induced in mice and humans with cardiomyopathy. Global and cardiac-specific lincRNA-p21 knockout significantly suppressed pressure overload-induced ventricular wall thickening, stress marker elevation, and deterioration of cardiac function. Genome-wide transcriptome analysis and transcriptional network analysis revealed that lincRNA-p21 acts in trans to stimulate the NFAT/MEF2 pathway. Mechanistically, lincRNA-p21 is bound to the scaffold protein KAP1. lincRNA-p21 cardiac-specific knockout suppressed stress-induced nuclear accumulation of KAP1, and KAP1 knockdown attenuated cardiac hypertrophy and NFAT activation. KAP1 positively regulates pathological hypertrophy by physically interacting with NFATC4 to promote the overactive status of NFAT/MEF2 signaling. GapmeR antisense oligonucleotide depletion of lincRNA-p21 similarly inhibited cardiac hypertrophy and adverse remodeling, highlighting the therapeutic potential of inhibiting lincRNA-p21.

CONCLUSIONS

These findings advance our understanding of the functional significance of stress-induced long noncoding RNA in cardiac hypertrophy and demonstrate the potential of lincRNA-p21 as a novel therapeutic target for cardiac hypertrophy and subsequent heart failure.

Epicardial Adipose Tissue is Associated with Geometry Alteration and Diastolic Dysfunction in Prediabetic Cardiomyopathy

BACKGROUND

Diastolic dysfunction and alterations in cardiac geometry are early indicators of diabetic cardiomyopathy. However, the association between cardiac changes across the glucose continuum and the contribution of epicardial adipose tissue (EAT) to these changes has not yet been investigated.

PURPOSE

In this study, we aim to investigated the EAT on cardiac diastolic function and structural alterations along the diabetic continuum using cardiac magnetic resonance imaging (CMRI).

METHODS

We enrolled individuals who were categorized into groups based on glucose tolerance status. Left ventricular structure and diastolic function were assessed using echocardiography and CMRI to determine the EAT, intramyocardial fat, and associated parameters. Multivariable logistic regression models were also used.

RESULTS

In a study of 370 patients (209 normal glucose tolerance, 82 prediabetes, 79 diabetes), those with prediabetes and diabetes showed increased heart dimensions and diastolic dysfunction, including E/E' (the ratio of early mitral inflow velocity to mitral annular early diastolic velocity) (7.9±0.51 vs. 8.5±0.64 vs. 10.0±0.93, p=0.010), left atrial volume index (28.21±14.7 vs. 33.2±12.8 vs. 37.4±8.2 mL/m2, p<0.001), and left ventricular peak filling rate (4.46±1.75 vs. 3.61±1.55 vs. 3.20±1.30 mL/s, p<0.001). EAT significantly increased in prediabetes and diabetes (26.3±1.16 vs. 31.3±1.83 vs. 33.9±1.9 gm, p=0.001), while intramyocardial fat did not differ significantly. Prediabetes altered heart geometry, but not diastolic function (OR 1.22 [1.02-1.83], p=0.012; and 1.70 [0.79-3.68], p=0.135). Diabetes significantly affected both heart structure and diastolic function (OR 1.42 [1.11-1.97], p=0.032; and 2.56 [1.03-5.40], p=0.034) after adjusting for covariates.

CONCLUSIONS

Elevated EAT was observed in patients with prediabetes and is associated with adverse alterations in cardiac structure and diastolic function, potentially serving as an underlying mechanism for the early onset of diabetic cardiomyopathy.