Cardio-oncology care in the era of the coronavirus disease 2019 (COVID-19) pandemic: An International Cardio-Oncology Society (ICOS) statement.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has given rise to a pandemic of unprecedented proportions in the modern era because of its highly contagious nature and impact on human health and society: coronavirus disease 2019 (COVID-19). Patients with cardiovascular (CV) risk factors and established CV disease (CVD) are among those initially identified at the highest risk for serious complications, including death. Subsequent studies have pointed out that patients with cancer are also at high risk for a critical disease course. Therefore, the most vulnerable patients are seemingly those with both cancer and CVD, and a careful, unified approach in the evaluation and management of this patient population is especially needed in times of the COVID-19 pandemic. This review provides an overview of the unique implications of the viral outbreak for the field of cardio-oncology and outlines key modifications in the approach to this ever-increasing patient population. These modifications include a shift toward greater utilization of cardiac biomarkers and a more focused CV imaging approach in the broader context of modifications to typical practice pathways. The goal of this strategic adjustment is to minimize the risk of SARS-CoV-2 infection (or other future viral outbreaks) while not becoming negligent of CVD and its important impact on the overall outcomes of patients who are being treated for cancer.

Heart Failure With Targeted Cancer Therapies: Mechanisms and Cardioprotection.

Oncology has seen growing use of newly developed targeted therapies. Although this has resulted in dramatic improvements in progression-free and overall survival, challenges in the management of toxicities related to longer-term treatment of these therapies have also become evident. Although a targeted approach often exploits the differences between cancer cells and noncancer cells, overlap in signaling pathways necessary for the maintenance of function and survival in multiple cell types has resulted in systemic toxicities. In particular, cardiovascular toxicities are of important concern. In this review, we highlight several targeted therapies commonly used across a variety of cancer types, including HER2 (human epidermal growth factor receptor 2)+ targeted therapies, tyrosine kinase inhibitors, immune checkpoint inhibitors, proteasome inhibitors, androgen deprivation therapies, and MEK (mitogen-activated protein kinase kinase)/BRAF (v-raf murine sarcoma viral oncogene homolog B) inhibitors. We present the oncological indications, heart failure incidence, hypothesized mechanisms of cardiotoxicity, and potential mechanistic rationale for specific cardioprotective strategies.

Cardiotoxicity of anticancer treatments: Epidemiology, detection, and management.

Answer questions and earn CME/CNE Cancer and heart disease are the leading causes of morbidity and mortality in the industrialized world. Modern treatment strategies have led to an improvement in the chances of surviving a diagnosis of cancer; however, these gains can come at a cost. Patients may experience adverse cardiovascular events related to their cancer treatment or as a result of an exacerbation of underlying cardiovascular disease. With longer periods of survival, late effects of cancer treatment may become clinically evident years or decades after completion of therapy. Current cancer therapy incorporates multiple agents whose deleterious cardiac effects may be additive or synergistic. Cardiac dysfunction may result from agents that can result in myocyte destruction, such as with anthracycline use, or from agents that appear to transiently affect left ventricular contractility. In addition, cancer treatment may be associated with other cardiac events, such as severe treatment-induced hypertension and vasospastic and thromboembolic ischemia, as well as rhythm disturbances, including QTc prolongation, that may be rarely life-threatening. Early and late effects of chest radiation can lead to radiation-induced heart disease, including pericardial disease, myocardial fibrosis, cardiomyopathy, coronary artery disease, valvular disease, and arrhythmias, in the setting of myocardial fibrosis. The discipline of cardio-oncology has developed in response to the combined decision making necessary to optimize the care of cancer patients, whether they are receiving active treatment or are long-term survivors. Strategies to prevent or mitigate cardiovascular damage from cancer treatment are needed to provide the best cancer care. This review will focus on the common cardiovascular issues that may arise during or after cancer therapy, the detection and monitoring of cardiovascular injury, and the best management principles to protect against or minimize cardiotoxicity during the spectrum of cancer treatment strategies. CA Cancer J Clin 2016;66:309-325. © 2016 American Cancer Society.

Defining cardiovascular toxicities of cancer therapies: an International Cardio-Oncology Society (IC-OS) consensus statement.

The discipline of Cardio-Oncology has seen tremendous growth over the past decade. It is devoted to the cardiovascular (CV) care of the cancer patient, especially to the mitigation and management of CV complications or toxicities of cancer therapies, which can have profound implications on prognosis. To that effect, many studies have assessed CV toxicities in patients undergoing various types of cancer therapies; however, direct comparisons have proven difficult due to lack of uniformity in CV toxicity endpoints. Similarly, in clinical practice, there can be substantial differences in the understanding of what constitutes CV toxicity, which can lead to significant variation in patient management and outcomes. This document addresses these issues and provides consensus definitions for the most commonly reported CV toxicities, including cardiomyopathy/heart failure and myocarditis, vascular toxicity, and hypertension, as well as arrhythmias and QTc prolongation. The current document reflects a harmonizing review of the current landscape in CV toxicities and the definitions used to define these. This consensus effort aims to provide a structure for definitions of CV toxicity in the clinic and for future research. It will be important to link the definitions outlined herein to outcomes in clinical practice and CV endpoints in clinical trials. It should facilitate communication across various disciplines to improve clinical outcomes for cancer patients with CV diseases.

Myocardial uptake of 68Ga-DOTATATE: correlation with cardiac disease and risk factors.

BACKGROUND: Myocardial uptake on 68Ga-DOTATATE PET/CT is often observed and its clinical relevance is poorly understood. PURPOSE: To detect any correlation between myocardial uptake of 68Ga-DOTATATE and presence of cardiac disease or risk factors. MATERIAL AND METHODS: In this institutional review board-approved retrospective study, we reviewed 68Ga-DOTATATE PET/CT scans in our institution between 1 May 2018 and 30 September 2018. A semi-quantitative score (MUS) for myocardial uptake of 68Ga-DOTATATE was developed by measuring mean standardized uptake value (SUV) in five myocardial regions, corrected by blood pool activity, and MUS was validated between two readers. We investigated the relationship between MUS and presence of cardiac disease or risk factors, including Framingham score and coronary calcification. RESULTS: A total of 145 scans were included (79 women; mean age = 56.9 ± 13.7 years). Inter-reader agreement was excellent with intraclass correlation coefficient (r) = 0.964 (95% confidence interval [CI] = 0.903-0.987; P < 0.001). There was a weak but significant positive correlation between MUS and presence of coronary calcifications (Spearman rho = 0.20; P = 0.016). MUS was higher in patients with heart disease or risk factors (n = 83, mean MUS 2.03, 95% CI = 1.85-2.21) compared to those without (n = 23, mean MUS 1.40, 95% CI = 1.17-1.62; P < 0.001), although the cardiac disease group was older with a higher percentage of men (62.0 years, 57.8% men compared to 47.6 years, 13.0% men; P value <0.0001 for both comparisons). CONCLUSION: For patients undergoing 68Ga-DOTATATE PET/CT scan, an elevated MUS might indicate an underlying heart disease.

Clinical Practice Guidelines in Cardio-Oncology.

Consensus statements on recommended definitions and practice in cardio-oncology have been developed. There is recognition of the potential for anthracyclines, trastuzumab, pertuzumab, immune checkpoint inhibitors, tyrosine kinase inhibitors, cyclophosphamide, and radiotherapy to cause left ventricular dysfunction and heart failure with heterogeneous natural histories. Cardiac function should be evaluated by echocardiography before the initiation of these therapies. For the prevention of cardiotoxicity, there is evidence to support the use of dexrazoxane under specific circumstances; existing research does not support the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers or ß-blockers in unselected individuals but should be considered in specific instances.

Cardiac biomarkers and association with subsequent cardiomyopathy and mortality among adult survivors of childhood cancer: A report from the St. Jude Lifetime Cohort.

BACKGROUND: Survivors of childhood cancer exposed to cardiotoxic therapies are at significant cardiovascular risk. The utility of cardiac biomarkers for identifying the risk of future cardiomyopathy and mortality is unknown. METHODS: N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT) were assessed in 1213 adults 10 or more years from a childhood cancer diagnosis; 786 were exposed to anthracycline chemotherapy and/or chest-directed radiation therapy (RT). NT-proBNP values above age- and sex-specific 97.5th percentiles were considered abnormal. Generalized linear models estimated cross-sectional associations between abnormal NT-proBNP and anthracycline or chest RT doses as risk ratios with 95% confidence intervals (CIs). A Poisson distribution estimated rates and a Cox proportional hazards model estimated hazard ratios (HRs) for future cardiac events and death. RESULTS: At a median age of 35.5 years (interquartile range, 29.8-42.5 years), NT-proBNP and cTnT were abnormal in 22.5% and 0.4%, respectively. Exposure to chest RT and exposure to anthracycline chemotherapy were each associated with a dose-dependent increased risk for abnormal NT-proBNP (P for trend <.0001). Among exposed survivors with no history of Common Terminology Criteria for Adverse Events-graded cardiomyopathy and with normal systolic function, survivors with abnormal NT-proBNP had higher rates per 1000 person-years of cardiac mortality (2.93 vs 0.96; P < .0001) and future cardiomyopathy (32.10 vs 15.98; P < .0001) and an increased risk of future cardiomyopathy (HR, 2.28; 95% CI, 1.28-4.08) according to a multivariable assessment. CONCLUSIONS: Abnormal NT-proBNP values were prevalent and, among survivors who were exposed to cardiotoxic therapy but did not have a history of cardiomyopathy or current systolic dysfunction, identified those at increased risk for future cardiomyopathy. Further longitudinal studies are needed to confirm this novel finding.

A multi-modal diagnostic model improves detection of cardiac amyloidosis among patients with diagnostic confirmation by cardiac biopsy.

BACKGROUND: Timely recognition of cardiac amyloidosis is clinically important, but the diagnosis is frequently delayed. OBJECTIVES: We sought to identify a multi-modality approach with the highest diagnostic accuracy in patients evaluated by cardiac biopsy, the diagnostic gold standard. METHODS: Consecutive patients (N = 242) who underwent cardiac biopsy for suspected amyloidosis within an 18-year period were retrospectively identified. Cardiac biomarker, ECG, and echocardiography results were examined for correlation with biopsy-proven disease. A prediction model for cardiac amyloidosis was derived using multivariable logistic regression. RESULTS: The overall cohort was characterized by elevated BNP (median 727 ng/mL), increased left ventricular wall thickness (IWT; median 1.7 cm), and reduced voltage-to-mass ratio (median 0.06 mm/[g/m2]). One hundred and thirteen patients (46%) had either light chain (n = 53) or transthyretin (n = 60) amyloidosis by cardiac biopsy. A prediction model including age, relative wall thickness, left atrial pressure by E/e', and low limb lead voltage (<0.5 mV) showed good discrimination for cardiac amyloidosis with an optimism-corrected c-index of 0.87 (95% CI 0.83-0.92). The diagnostic accuracy of this model (79% sensitivity, 84% specificity) surpassed that of traditional screening parameters, such as IWT in the absence of left ventricular hypertrophy on ECG (98% sensitivity, 20% specificity) and IWT with low limb lead voltage (49% sensitivity, 91% specificity). CONCLUSION: Among patients with an advanced infiltrative cardiomyopathy phenotype, traditional biomarker, ECG, and echocardiography-based screening tests have limited individual diagnostic utility for cardiac amyloidosis. A prediction algorithm including age, relative wall thickness, E/e', and low limb lead voltage improves the detection of cardiac biopsy-proven disease.

Cardiovascular Events in Men with Prostate Cancer Receiving Hormone Therapy: An Analysis of the FDA Adverse Event Reporting System (FAERS).

PURPOSE: The comparative cardiovascular risk profiles of available hormone therapies for the treatment of prostate cancer is not known. MATERIALS AND METHODS: We queried the U.S. Food and Drug Administration Adverse Event Reporting System, a retrospective, pharmacovigilance database, for cardiovascular adverse event reports in men with prostate cancer receiving gonadotropin releasing hormone (GnRH) agonists, GnRH antagonists, androgen receptor antagonists, and/or androgen synthesis inhibitors from January 2000 to April 2020. RESULTS: Cardiovascular adverse events accounted for 6,231 reports (12.6%) on hormone monotherapy and 1,793 reports (26.1%) on combination therapy. Arterial vascular events were reported most commonly, followed by arrhythmias, heart failure, and venous thromboembolism. Compared to GnRH agonists, GnRH antagonists were associated with fewer cardiovascular adverse event reports as monotherapy (adjusted reporting odds ratio [ROR]=0.70 [95% CI 0.59-0.84], p <0.001) and as combination therapy (ROR=0.47 [0.34-0.67], p <0.0001), driven by reductions in arterial vascular events. Second generation androgen receptor antagonists and abiraterone were associated with more reports of hypertension requiring hospitalization (ROR=1.21 [1.03-1.41], p=0.02 and ROR=1.19 [1.01-1.40], p=0.03, respectively), and more heart failure events when used in combination with GnRH antagonists (ROR=2.79 [1.30-6.01], p=0.009 and ROR=2.57 [1.12-5.86], p=0.03). CONCLUSIONS: In this retrospective analysis of a pharmacovigilance database, arterial vascular events were the most commonly reported cardiovascular adverse events in men on hormone therapy for prostate cancer. GnRH antagonists were associated with fewer reports of overall cardiovascular events and arterial vascular events than GnRH agonists. Additional study is needed to identify optimal strategies to reduce cardiovascular morbidity among men with prostate cancer receiving hormone therapy.

Prevention, Monitoring, and Management of Cardiac Dysfunction in Patients with Metastatic Breast Cancer.

Cardiac monitoring is becoming an important part of breast cancer care. Breast cancer and cardiovascular disease (CVD) share many common risk factors, and it is estimated that by the median age of diagnosis, many patients with breast cancer will have established or subclinical CVD. In addition, a number of treatments for metastatic breast cancer are known to have cardiac effects. As such, there is a clear need to prevent, identify, and effectively manage cardiovascular events in patients with breast cancer. Current clinical practice for patients with metastatic breast cancer involves a comprehensive set of assessments to ensure efficacy and safety of treatment. Adding cardiac monitoring to the assessments already required for patients with breast cancer may improve survival and quality of life. Currently, cardiac monitoring is recommended for several breast cancer treatments, and guidelines related to cardiac monitoring are available. Here, we review the risk of CVD in patients with breast cancer, providing an overview of the cardiac events associated with standard therapies for metastatic breast cancer. We also assess the current clinical recommendations relating to cardiac monitoring, and practical management strategies for oncologists. Cardio-oncology is a growing medical subspecialty that promotes the need for effective cancer therapy while minimizing cardiac effects. Integrating cardiac monitoring into routine clinical practice may safeguard patients with metastatic breast cancer against adverse cardiac effects. IMPLICATIONS FOR PRACTICE: This review details the common risk factors associated with cardiovascular disease that are frequently observed in patients with metastatic breast cancer, as well as the adverse cardiac effects of many therapies that are commonly prescribed. The review also provides a rationale for routine and comprehensive cardiovascular assessment of all patients at baseline, and during and after therapy depending on the treatment and presence of risk factors for cardiovascular disease. The medical discipline of cardio-oncology is increasingly being recognized as an important part of clinical practice to ensure effective cancer therapy while maintaining cardiac health.

Hypertension in the Cardio-Oncology Clinic.

As cancer therapies improve, the population of survivors of cancer has increased, and the long-term effects of cancer treatments have become more apparent. Cardiotoxicity is a well-established adverse effect of many antineoplastic agents. Hypertension is common in survivors of cancer, can be caused or worsened by certain agents, and has been shown to increase the risk of other cardiovascular diseases including heart failure. Pretreatment risk assessment and careful monitoring of blood pressure during therapy is essential. Aggressive management of preexisting or incident hypertension in survivors of cancer is paramount to decrease the risk of heart failure and other cardiovascular diseases in these patients.

Recurrent cardiotoxicity potentiated by the interaction of proteasome inhibitor and immunomodulatory therapy for the treatment of multiple myeloma.

Patients with multiple myeloma (MM) have improved treatment options, including immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs). Despite their efficacy, increased rates of cardiovascular (CV) complications occur in patients exposed to some of these therapies. While previous research has focused on identifying the toxicities inherent to each specific agent, the CV side effects may be potentiated by the combination of PIs and IMiDs plus dexamethasone. We present a patient with MM with recurrent cardiotoxicity only when exposed to combination PI and IMiD-based therapy. We also review the literature in this context, and propose a potential algorithm for cardiotoxicity prevention in this population.

Effects of endogenous serum neuregulin-1ß on morbidity and mortality in patients with heart failure and left ventricular systolic dysfunction.

CONTEXT: Improved left ventricular ejection fraction (LVEF) following administration of recombinant human Neuregulin-1ß (NRG), epidermal growth factor (EGF) involved in cardiomyocyte repair/survival, has been observed in patients with systolic heart failure (HF). METHODS: Serum NRG was measured by ELISA in 248 patients with NYHA class I-IV HF. RESULTS: NRG exhibited a marginally significant effect on LVEF trajectory over 11 months (p = 0.07). There is no apparent level of NRG that predicts improved survival. CONCLUSIONS: There is a potential relationship between serum NRG and improved LVEF, indicating the need to investigate the utility of NRG in predicting HF outcomes, including LVEF maintenance.

Exercise right heart catheterization for pulmonary hypertension identified on screening echocardiography in adult survivors of childhood cancer: A report from the St. Jude Lifetime Cohort.

Pulmonary hypertension, determined noninvasively by tricuspid regurgitant jet velocity on Doppler echocardiography, was previously identified in 25% of long-term survivors who received chest-directed radiotherapy. To validate noninvasively defined pulmonary hypertension, survivors (mean age 48 years), exposed to chest radiotherapy, underwent right heart catheterization with planned cardiopulmonary exercise testing during catheterization. Eight participants had an elevated mean pulmonary artery pressure at rest (≥25 mm Hg) or with subsequent exercise (>30 mm Hg), evidence of hemodynamically confirmed pulmonary hypertension by right heart catheterization. Cardiopulmonary exercise testing further defined the magnitude and etiology of cardiopulmonary limitations in this life-threatening late effect.

The relationship between pulmonary artery wedge pressure and pulmonary blood volume derived from contrast echocardiography: A proof-of-concept study.

BACKGROUND: Pulmonary transit time (PTT) obtained from contrast echocardiography is a marker of global cardiopulmonary function. Pulmonary blood volume (PBV), derived from PTT, may be a noninvasive surrogate for left-sided filling pressures, such as pulmonary artery wedge pressure (PAWP). We sought to assess the relationship between PBV obtained from contrast echocardiography and PAWP. METHODS: Participants were adult survivors of childhood cancer that had contrast echocardiography performed nearly simultaneously with right-heart catheterization. PTT was derived from time-intensity curves of contrast passage through the right ventricle (RV) and left atrium (LA). PBV relative to overall stroke volume (rPBV) was estimated from the product of PTT and heart rate during RV-LA transit. PAWP was obtained during standard right-heart catheterization. The Spearman correlation coefficient was used to assess the relationship between rPBV and PAWP. RESULTS: The study population consisted of 7 individuals who had contrast echocardiography and right-heart catheterization within 3 hours of each other. There was a wide range of right atrial (1-17 mm Hg), mean pulmonary artery (18-42 mm Hg), and PAW pressures (4-26 mm Hg) as well as pulmonary vascular resistance (<1-6 Wood Units). We observed a statistically significant correlation between rPBV and PAWP (r = .85; P = .02). CONCLUSION: Relative PBV derived from contrast echocardiography correlates with PAWP. If validated in larger studies, rPBV could potentially be used as an alternative to invasively determine left-sided filling pressure.

Management of Cancer Therapeutics-Related Cardiac Dysfunction.

Improvements in detection and treatment of cancer have resulted in a significant increase in cancer survivors. However, cancer survivorship comes with long-term risk of adverse effects of cancer therapies, including cardiomyopathy, heart failure, arrhythmias, ischemic heart disease, atherosclerosis, thrombosis, and hypertension. There is a renewed interest in understanding the pathophysiology of cancer therapeuticserelated cardiac dysfunction. In recent years, efforts have been directed to the management of cancer therapeuticserelated cardiac dysfunction. This article discusses the pathophysiology and molecular mechanisms that contribute to cancer therapeutics-related cardiac dysfunction and presents an napproach to the evaluation and treatment of these patients.

Outcomes from Autologous Hematopoietic Cell Transplantation versus Chemotherapy Alone for the Management of Light Chain Amyloidosis.

Light chain amyloidosis (AL) results in tissue deposition of misfolded proteins, causing organ dysfunction. In an era of modern therapies, such as bortezomib, reassessment of the benefit of autologous hematopoietic cell transplantation (AHCT) should be considered. In this study, we compared outcomes between patients with AL receiving chemotherapy alone (CT) and those undergoing AHCT. Seventy-four patients with AL were analyzed retrospectively. Two cohorts of patients were studied, those receiving CT (n = 31) and those undergoing AHCT (n = 43). Of the 43 patients in the AHCT cohort, 29 received induction chemotherapy before AHCT, whereas 14 proceeded straight to AHCT without induction therapy. Compared with the CT cohort, patients in the AHCT cohort were younger and had higher ejection fractions, lower brain natriuretic peptide levels, and more severe proteinuria. The majority (87%) of patients in the CT cohort received bortezomib-based treatment. Transplantation-related mortality (TRM) was 7%. Patients receiving AHCT were more likely to achieve complete or very good partial response (P = .048). The median progression-free survival (PFS) and overall survival (OS) were superior in the AHCT cohort (not reached versus 9 months; P < .01 and 74 months versus 8 months; P = .03, respectively). Multivariable analysis demonstrated that improved PFS (hazard ratio, 3.86; 95% confidence interval [CI] 1.3 to 11.5; P = .02) and OS (hazard ratio, 5.6; 95% CI, 1.9 to 16; P < .001) were associated with use of AHCT compared with CT. Patients in the AHCT cohort had deeper and longer durations of response, with superior PFS and OS, compared with those in the CT cohort. Despite the limitations of this study, AHCT should be considered for eligible patients with AL at experienced transplantation centers that can offer this therapy with a low risk of TRM.

Genome-wide association and pathway analysis of left ventricular function after anthracycline exposure in adults.

BACKGROUND: Anthracyclines are important chemotherapeutic agents, but their use is limited by cardiotoxicity. Candidate gene and genome-wide studies have identified putative risk loci for overt cardiotoxicity and heart failure, but there has been no comprehensive assessment of genomic variation influencing the intermediate phenotype of anthracycline-related changes in left ventricular (LV) function. The purpose of this study was to identify genetic factors influencing changes in LV function after anthracycline chemotherapy. METHODS: We conducted a genome-wide association study (GWAS) of change in LV function after anthracycline exposure in 385 patients identified from BioVU, a resource linking DNA samples to de-identified electronic medical record data. Variants with P values less than 1×10 were independently tested for replication in a cohort of 181 anthracycline-exposed patients from a prospective clinical trial. Pathway analysis was performed to assess combined effects of multiple genetic variants. RESULTS: Both cohorts were middle-aged adults of predominantly European descent. Among 11 candidate loci identified in discovery GWAS, one single nucleotide polymorphism near PR domain containing 2, with ZNF domain (PRDM2), rs7542939, had a combined P value of 6.5×10 in meta-analysis. Eighteen Kyoto Encyclopedia of Gene and Genomes pathways showed strong enrichment for variants associated with the primary outcome. Identified pathways related to DNA repair, cellular metabolism, and cardiac remodeling. CONCLUSION: Using genome-wide association we identified a novel candidate susceptibility locus near PRDM2. Variation in genes belonging to pathways related to DNA repair, metabolism, and cardiac remodeling may influence changes in LV function after anthracycline exposure.

ERBB signaling attenuates proinflammatory activation of nonclassical monocytes.

Immune activation in chronic systolic heart failure (HF) correlates with disease severity and prognosis. Recombinant neuregulin-1 (rNRG-1) is being developed as a possible therapy for HF, based on the activation of ERBB receptors in cardiac cells. Work in animal models of HF led us to hypothesize that there may be direct effects of NRG-1 on immune system activation and inflammation. We investigated the expression of ERBB receptors and the effect of rNRG-1 isoform glial growth factor 2 (GGF2) in subpopulations of peripheral blood mononuclear cells (PB MNCs) in subjects with HF. We found that human monocytes express both ERBB2 and ERBB3 receptors, with high interindividual variability among subjects. Monocyte surface ERBB3 and TNF-α mRNA expression were inversely correlated in subjects with HF but not in human subjects without HF. GGF2 activation of ERBB signaling ex vivo inhibited LPS-induced TNF-α production, specifically in the CD14lowCD16+ population of monocytes in a phosphoinositide 3-kinase-dependent manner. GGF2 suppression of TNF-α correlated directly with the expression of ERBB3. In vivo, a single dose of intravenous GGF2 reduced TNF-α expression in PB MNCs of HF subjects participating in a phase I safety study of GGF2. These results support a role for ERBB3 signaling in the regulation of TNF-α production from CD14lowCD16+ monocytes and a need for further investigation into the clinical significance of NRG-1/ERBB signaling as a modulator of immune system function.NEW & NOTEWORTHY This study identified a novel role of neuregulin-1 (NRG-1)/ERBB signaling in the control of proinflammatory activation of monocytes. These results further improve our fundamental understanding of cardioprotective effects of NRG-1 in patients with heart failure.