Understanding Obesity-Related High Output Heart Failure and Its Implications

Olanzapine-induced cardiomyopathy: A mimicker of obesity cardiomyopathy?

Olanzapine, an atypical antipsychotic medication, has gained prominence in the treatment of schizophrenia and related psychotic disorders due to its effectiveness and perceived safety profile. However, emerging evidence suggests a potential link between olanzapine use and adverse cardiovascular effects, including cardiomyopathy. This narrative review explores the mechanisms, clinical implications, and management strategies associated with olanzapine-induced cardiomyopathy. A comprehensive review of the literature was conducted to investigate the relationship between olanzapine and cardiomyopathy. The search included epidemiological studies, clinical case reports, and mechanistic research focusing on the pathophysiology of olanzapine-induced cardiomyopathy. The review also examined treatment strategies for managing this potential complication. Olanzapine-induced cardiomyopathy is hypothesized to be associated with metabolic disturbances and receptor antagonism. The metabolic effects of olanzapine, such as weight gain, insulin resistance, and dyslipidemia, share similarities with obesity-related cardiomyopathy. Additionally, olanzapine's antagonism of certain receptors may contribute to cardiovascular stress. The review highlighted that patients with new-onset heart failure and significant weight gain while on olanzapine should be closely monitored for signs of cardiomyopathy. Early detection and prompt withdrawal of olanzapine, along with initiation of goal-directed medical therapy, are crucial for mitigating this potentially life-threatening condition. The relationship between olanzapine and cardiomyopathy is complex and not yet fully understood. However, the potential for significant cardiovascular risk necessitates vigilance among healthcare providers. Early identification and management of olanzapine-induced cardiomyopathy can improve patient outcomes. Further research is needed to elucidate the precise mechanisms behind this adverse effect and to develop optimized treatment strategies for patients requiring antipsychotic therapy.

Epicardial Adipose Tissue and Heart Failure, Friend or Foe?

Heart failure (HF) management guidelines recommend individualized assessments based on HF phenotypes. Adiposity is a known risk factor for HF. Recently, there has been an increased interest in organ-specific adiposity, specifically the role of the epicardial adipose tissue (EAT), in HF risk. EAT is easily assessable through various imaging modalities and is anatomically and functionally connected to the myocardium. In pathological conditions, EAT secretes inflammatory cytokines, releases excessive fatty acids, and increases mechanical load on the myocardium, resulting in myocardial remodeling. EAT plays a pathophysiological role in characterizing both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). In HFrEF, EAT volume is reduced, reflecting an impaired metabolic reservoir, whereas in HFpEF, the amount of EAT is associated with worse biomarker and hemodynamic profiles, indicating increased EAT activity. Studies have examined the possibility of therapeutically targeting EAT, and recent studies using sodium glucose cotransporter 2 inhibitors have shown potential in reducing EAT volume. However, further research is required to determine the clinical implications of reducing EAT activity in patients with HF.

Physics-based in silico modelling of microvascular pulmonary perfusion in COVID-19

Due to its ability to induce heterogenous, patient-specific damage in pulmonary alveoli and capillaries, COVID-19 poses challenges in defining a uniform profile to elucidate infection across all patients. Computational models that integrate changes in ventilation and perfusion with heterogeneous damage profiles offer valuable insights into the impact of COVID-19 on pulmonary health. This study aims to develop an in silico hypothesis-testing platform specifically focused on studying microvascular pulmonary perfusion in COVID-19-infected lungs. Through this platform, we explore the effects of various acinar-level pulmonary perfusion abnormalities on global lung function. Our modelling approach simulates changes in pulmonary perfusion and the resulting mismatch of ventilation and perfusion in COVID-19-afflicted lungs. Using this coupled modelling platform, we conducted multiple simulations to assess different scenarios of perfusion abnormalities in COVID-19-infected lungs. The simulation results showed an overall decrease in ventilation-perfusion (V/Q) ratio with inclusion of various types of perfusion abnormalities such as hypoperfusion with and without microangiopathy. This model serves as a foundation for comprehending and comparing the spectrum of findings associated with COVID-19 in the lung, paving the way for patient-specific modelling of microscale lung damage in emerging pulmonary pathologies like COVID-19.

The Effect of Intermittent Pneumatic Compression on Hemodynamics and Regional Cerebral Oxygen Saturation in Laparoscopic Bariatric Surgery with Mild Hypercapnia in the Steep Reverse Trendelenburg Position

Obesity negatively affects hemodynamics and cerebral physiology. We investigated the effect of the utilization of an intermittent pneumatic compression (IPC) device on hemodynamics and cerebral physiology in patients undergoing laparoscopic bariatric surgery under general anesthesia with lung-protective ventilation. Sixty-four patients (body mass index > 30 kg/m2) were randomly assigned to groups that received an IPC device (IPC group, n = 32) and did not (control group, n = 32). The mean arterial pressure (MAP), heart rate (HR), need for vasopressors, cerebral oxygen saturation (rSO2), and cerebral desaturation events were recorded. The incidence of intraoperative hypotension was not significantly different between groups (p = 0.153). Changes in MAP and HR over time were similar between groups (p = 0.196 and p = 0.705, respectively). The incidence of intraoperative cerebral desaturation was not significantly different between groups (p = 0.488). Changes in rSO2 over time were similar between the two groups (p = 0.190) during pneumoperitoneum. Applying IPC to patients with obesity in the steep reverse Trendelenburg position may not improve hemodynamic parameters, vasopressor requirements, or rSO2 values during pneumoperitoneum under lung-protective ventilation. During laparoscopic bariatric surgery, IPC alone has limitations in improving hemodynamics and cerebral physiology.

Adipokines and Their Role in Heart Failure: A Literature Review

Obesity is a major risk factor for heart failure (HF). The relationship between adipokines and HF has been implicated in many previous studies and reviews. However, this review article summarizes the basic role of major adipokines, such as apelin, adiponectin, chemerin, resistin, retinol-binding protein 4 (RBP4), vaspin, visfatin, plasminogen activator inhibitor-1, monocyte chemotactic protein-1, nesfatin-1, progranulin, leptin, omentin-1, lipocalin-2, and follistatin-like 1 (FSTL1), in the pathogenesis of HF. Apelin is reduced in patients with HF and upregulated following favorable left ventricular (LV) remodeling. Higher levels of adiponectin have been found in patients with HF compared to in control patients. Also, high plasma chemerin levels are linked to a higher risk of HF. Serum resistin is related to the severity of HF and associated with a high risk for adverse cardiac events. Evidence indicates that RBP4 can contribute to inflammation and damage heart muscle cells, potentially leading to HF. Vaspin might stop the progression of cardiac degeneration, fibrosis, and HF according to experiments on rats with experimental isoproterenol-induced chronic HF. The serum concentrations of visfatin are significantly lower in patients with systolic HF. Leptin levels were found to be correlated with low LV mass and myocardial stiffness, both of which are significant risk factors for the development of HF with preserved ejection fraction (HFpEF). Measuring serum omentin-1 levels appears to be a novel prognostic indicator for risk stratification in HF patients. Increased expression of neutrophil gelatinase-associated lipocalin in both systemic circulation and myocardium in clinical and experimental HF suggests that innate immune responses may contribute to the development of HF. FSTL1 was elevated in patients with HF with reduced ejection fraction and associated with an increase in the size of the left ventricle of the heart. However, other adipokines, such as plasminogen activator inhibitor-1, monocyte chemotactic protein-1, nesfatin-1, and progranulin, have not yet been studied for HF.

Differences in Leukocyte Transcriptomes of Morbidly Obese Patients With High Output Heart Failure: A Pilot Study

Background and Objectives

Heart failure is characterized by alterations of gene expression that provide insight into the underlying pathophysiologic mechanisms. However, obesity-related high output heart failure (HOHF) is a specific phenotype of heart failure that has not been studied using gene expression. Our aim in this study was to examine the variances in leukocyte transcriptomes of morbidly obese patients with HOHF.

Methods

In this cross-sectional study, we applied stranded total RNA-sequencing to six patients with morbid obesity and HOHF and 6 patients with morbid obesity and non-HOHF. Differential gene expression was calculated, and Ingenuity Pathway Analysis software was used to interpret the canonical pathways, functional changes, upstream regulators, and networks in these patients.

Results

We found in patients with HOHF that there were 116 differentially expressed genes with upregulation of 114 genes and downregulation of 2 genes. The differentially expressed genes were involved with cell proliferation, mitochondrial function, erythropoiesis, erythrocyte stability, and apoptosis. The top upregulated canonical pathways associated with differentially expressed genes were autophagy, adenosine monophosphate-activated protein kinase signaling, and senescence pathways. We identified GATA binding protein 1 as an upstream regulator and nuclear factor kappa-light-chain-enhancer of activated B cells associated network.

Conclusions

We are the first to report the differential gene expression in patients with obesity-related HOHF and reveal the various pathophysiologic mechanisms underlying the disease. Further research is needed to determine the role of cellular function and maintenance, inflammation, and iron homeostasis in obesity-related HOHF.

A case report of high-output heart failure due to arteriovenous shunt without bowel: how to address?

Background

High-output heart failure (HF) is a form of HF where patients present with a high-output state with low systemic vascular resistance. This report presents the case of high-output HF in a patient with an arteriovenous shunt and no options for oral-administered drugs.

Case summary

A 70-year-old male with a terminal jejunostomy fully depending on parenteral feeding through a vena saphena magna shunt presented with symptoms of shortness of breath. Echocardiography revealed eccentric hypertrophy with reduced left ventricular ejection fraction (LVEF) and atrial fibrillation with a heart rate of 70-100 b.p.m. Cardiac magnetic resonance imaging, endomyocardial biopsy, and cardiomyopathy lab revealed no cause of HF. High-output HF based on right heart catheterization due to the arteriovenous shunt or related to irregularity due to atrial fibrillation were potential causes. As a result of his malfunctioning gastrointestinal system, the pharmacological options were limited. He was treated with captopril sublingual, initially 6.25 mg three times daily (TID) and later 12.5 mg TID, which reduced blood pressure. Electrical cardioversion to sinus rhythm was successful but did not improve LVEF. Therefore, the patient was opted for surgically reducing the blood flow through the shunt, resulting in normalization of LVEF.

Discussion

High-output HF is an uncommon form of HF with an uncertain prevalence. The most common aetiologies reported in the literature are obesity, cirrhosis, and arteriovenous shunts. Sublingual administration of captopril can be an effective treatment option for HF patients unable to absorb oral-administered drugs.

Obesity-related hypertension and chronic kidney disease: from evaluation to management

With the recent obesity pandemic, obesity-related hypertension and its complications (e.g., heart failure, coronary disease, and chronic kidney disease [CKD]) are gaining attention in clinical and research fields. Obesity-related hypertension frequently precedes the onset of CKD and aggravates its progression. In this review, we discuss the role of visceral fat in the pathophysiology of obesity-related hypertension and the potential therapeutic strategies for its prevention and management. Various factors, including the sympathetic nervous system, renin-angiotensin-aldosterone system, and inflammatory pathways, are intricately involved in the pathogenesis of obesity-related hypertension. These factors individually and jointly contribute to the development of hypertension (usually sodium-sensitive or resistant hypertension) and, ultimately, to the progression of CKD. From a clinical standpoint, a decline in renal function in advanced CKD further makes blood pressure control challenging since only a few options are available for blood pressure-lowering medications. Proactive lifestyle modification, pharmacological treatment for obesity, and bariatric surgery can be considered for obesity control and management. Furthermore, intensive blood pressure control is required to prevent and halt the development and progression of CKD.

Clinical outcomes and 30-day readmissions associated with high-output heart failure

BACKGROUND

High-output heart failure (HOHF) is an underdiagnosed type of heart failure (HF) characterized by low systemic vascular resistance and high cardiac output.

OBJECTIVE

This study sought to characterize the causes, mortality, and readmissions related to HOHF within the United States.

METHODS

Data were collected from the Agency for Healthcare Research and Quality's Healthcare Cost and Utilization Project (HCUP) National Readmissions Database (NRD) from January 1, 2017, to November 30, 2019. We used the International Classification of Diseases, 10th revision (ICD-10), diagnostic codes to identify encounters with HOHF and heart failure with reduced ejection fraction (HFrEF).

RESULTS

Of the total 5,080,985 encounters with HF, 3,897 hospitalizations (mean age 62.5 ± 17.9 years, 56.5% females) with HOHF and 5,077,088 hospitalizations with HFrEF were recorded. The most commonly associated putative etiologies of HOHF included pulmonary disease (19.8%), morbid obesity (9.9%), sepsis (9.6%), cirrhosis (8.9%), myelodysplastic syndrome (MDS) (7.9%), hyperthyroidism (5.5%), and sickle cell disease (3.3%). There was no significant difference in mortality rates [4.3% vs. 5.2%; odds ratio (OR) 0.9, 95% confidence interval (CI) 0.7-1.2] between HOHF and HFrEF. However, the 30-day readmission rate for HOHF was significantly lower than that for HFrEF (5.7% vs. 21.2%; OR 0.39, 95% CI 0.30-0.51). Cardiovascular (39.9%) followed by hematological (20.6%) complications accounted for the majority of 30-day readmissions in the HOHF group.

CONCLUSIONS

HOHF is an infrequently reported cardiovascular complication associated with noncardiovascular disorders and is encountered in 0.07% of all encounters with HF. Although comparable in-hospital mortality between studied cohorts was observed, raising awareness and timely recognition of this entity are warranted.

Obesity-Related High-Output Heart Failure: An Integrative Review

BACKGROUND

High-output heart failure (HF) is a type of HF characterized by signs and symptoms of HF and a cardiac output of 8 L/min or greater or a cardiac index greater than 3.9 L/min/m 2 . High-output HF occurs secondary to an underlying condition that requires high cardiac output due to an increase in oxygen consumption or decreased systemic vascular resistance. Obesity is a major cause of high-output HF, yet there is limited research on obesity-related high-output HF. Thus, the pathophysiologic mechanisms of this syndrome are not fully understood.

OBJECTIVE

The objectives of this integrative review were to describe the current state of the research regarding obesity-related high-output HF and to recommend direction for future research.

METHODS

We conducted an integrative review focusing on the peer-reviewed literature on patients with obesity-related high-output HF using Whittemore and Knafl's methodology. MEDLINE, CINAHL, and EMBASE electronic databases were searched for all publications indexed in the databases as of March 9, 2022. A narrative synthesis of definitions and symptoms, obesity as an underlying condition, pathophysiology, and treatments of obesity-related high-output HF was completed.

RESULTS

A total of 6 articles were included in the integrative review, with 1 nonexperimental, retrospective study and 5 literature reviews. Understanding of obesity-related high-output HF is very limited because of scant empirical evidence in the existing literature. Possible pathophysiologic mechanisms include increased pressure in the upper airways, adipokine dysregulation, increased metabolic activity, and insulin resistance.

CONCLUSION

Additional research is needed on the pathophysiologic mechanisms of obesity-related high-output HF to begin investigations on therapeutic interventions to improve health outcomes.

Treatment of heart failure with a preserved ejection fraction

Background: Heart failure with preserved ejection fraction (HFpEF) is increasingly prevalent, is associated with high morbidity, and has very few effective treatments.Current Concepts: HFpEF is a heterogeneous syndrome arising from the interplay of cardiac (diastolic, systolic dysfunction, pulmonary hypertension, right ventricular dysfunction, left atrial dysfunction, and chronotropic incompetence) and extracardiac (endothelial dysfunction, skeletal muscle abnormality, pulmonary disease, and renal dysfunction) abnormalities. Although various pharmacological therapies of HFpEF have been introduced and studied, most of them showed a limited clinical benefit. With some advancement in the specific phenotype of HFpEF, diuretics, mineralocorticoid antagonists, sacubitril/valsartan, and lifestyle modifications are recommended as important treatments. Recently, EMPEROR-Preserved trials showed that empagliflozin reduced the combined risk of cardiovascular death or hospitalization for patients with HFpEF, regardless of the presence or absence of diabetes. Several non-pharmacological therapies, including interatrial septal shunt and pacing therapies, have been introduced and are under investigation.Discussion and Conclusion: HFpEF has been recognized as the single greatest unmet need in cardiovascular medicine. Further research is required to understand the concrete pathophysiology for each phenotype of HFpEF. Prevention and management of comorbidities and risk factors for HFpEF are of great importance. Sodiumglucose cotransporter 2 inhibitors may contribute to a change in clinical practice, given the lack of therapeutic options available for patients with HFpEF.

Pathophysiology of Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a major public health problem that affects half of all patients with HF. It is rising in prevalence, is associated with high morbidity and mortality, and has very few effective treatments. HFpEF is currently understood as a heterogeneous syndrome originating from the interplay of cardiac and extracardiac abnormalities. The most important pathophysiology in patients with HFpEF is diastolic dysfunction, which presents with impairments in relaxation or increases in chamber stiffness that lead to an increase in left ventricular filling pressures at rest or during exercise that causes dyspnea.