Heart Failure Therapies for End-Stage Chemotherapy-Induced Cardiomyopathy

Single-Cell Transcriptomic Analysis Reveals Myocardial Fibrosis Mechanism of Doxorubicin-Induced Cardiotoxicity

Myocardial fibrosis is a pathological feature of doxorubicin-induced chronic cardiotoxicity that severely affects the prognosis of oncology patients. However, the specific cellular and molecular mediators driving doxorubicin-induced cardiac fibrosis, and the relative impact of different cell populations on cardiac fibrosis, remain unclear.This study aimed to explore the mechanism of doxorubicin-induced cardiotoxicity and myocardial fibrosis and to find potential therapeutic targets. Single-cell RNA sequencing was used to analyze the transcriptome of non-cardiomyocytes from normal and doxorubicin-induced chronic cardiotoxicity in mouse model heart tissue.We established a mouse model of doxorubicin-induced cardiotoxicity with a well-defined fibrotic phenotype. Analysis of single-cell sequencing results showed that fibroblasts were the major origin of extracellular matrix in doxorubicin-induced myocardial fibrosis. Further resolution of fibroblast subclusters showed that resting fibroblasts were converted to matrifibrocytes and then to myofibroblasts to participate in the myocardial remodeling process in response to doxorubicin treatment. Ctsb expression was significantly upregulated in fibroblasts after doxorubicin-induced.This study provides a comprehensive map of the non-cardiomyocyte landscape at high resolution, reveals multiple cell populations contributing to pathological remodeling of the cardiac extracellular matrix, and identifies major cellular sources of myofibroblasts and dynamic gene-expression changes in fibroblast activation. Finally, we used this strategy to detect potential therapeutic targets and identified Ctsb as a specific target for fibroblasts in doxorubicin-induced myocardial fibrosis.

NADPH oxidase 2 mediates cardiac sympathetic denervation and myocyte autophagy, resulting in cardiac atrophy and dysfunction in doxorubicin-induced cardiomyopathy

Doxorubicin has been used extensively as a potent anticancer agent, but its clinical use is limited by its cardiotoxicity. However, the underlying mechanisms remain to be fully elucidated. In this study, we tested whether NADPH oxidase 2 (Nox2) mediates cardiac sympathetic nerve terminal abnormalities and myocyte autophagy, resulting in cardiac atrophy and dysfunction in doxorubicin-induced heart failure. Nox2 knockout (KO) and wild-type (WT) mice were randomly assigned to receive a single injection of doxorubicin (15 mg/kg, i.p.) or saline. WT doxorubicin mice exhibited the decreases in survival rate, left ventricular (LV) wall thickness and LV fractional shortening and the increase in the lung wet-to-dry weight ratio 1 week after the injections. These alterations were attenuated in Nox2 KO doxorubicin mice. In WT doxorubicin mice, myocardial oxidative stress was increased, myocardial noradrenergic nerve fibers were reduced, myocardial expression of PGP9.5, GAP43, tyrosine hydroxylase and norepinephrine transporter was decreased, and these changes were prevented in Nox2 KO doxorubicin mice. Myocyte autophagy was increased and myocyte size was decreased in WT doxorubicin mice, but not in Nox2 KO doxorubicin mice. Nox2 mediates cardiac sympathetic nerve terminal abnormalities and myocyte autophagy-both of which contribute to cardiac atrophy and failure after doxorubicin treatment.

NADPH oxidase 2 inhibitor GSK2795039 prevents doxorubicin-induced cardiac atrophy by attenuating cardiac sympathetic nerve terminal abnormalities and myocyte autophagy

Doxorubicin is widely used for the treatment of human cancer, but its clinical use is limited by a cumulative dose-dependent cardiotoxicity. However, the mechanism of doxorubicin-induced cardiac atrophy and failure remains to be fully understood. In this study, we tested whether the specific NADPH oxidase 2 (Nox2) inhibitor GSK2795039 attenuates cardiac sympathetic nerve terminal abnormalities and myocyte autophagy, leading to the amelioration of cardiac atrophy and dysfunction in chronic doxorubicin-induced cardiomyopathy. Mice were randomized to receive saline, doxorubicin (2.5 mg/kg, every other day, 6 times) or doxorubicin plus GSK2795039 (2.5 mg/kg, twice a day, 9 weeks). Left ventricular (LV) total wall thickness and LV ejection fraction were decreased in doxorubicin-treated mice compared with saline-treated mice and the decreases were prevented by the treatment of the specific Nox2 inhibitor GSK2795039. The ratio of total heart weight to tibia length and myocyte cross-sectional area were decreased in doxorubicin-treated mice, and the decreases were attenuated by the GSK2795039 treatment. In doxorubicin-treated mice, myocardial Nox2 and 4-hydroxynonenal levels were increased, myocardial expression of GAP43, tyrosine hydroxylase and norepinephrine transporter, markers of sympathetic nerve terminals, was decreased, and these changes were prevented by the GSK2795039 treatment. The ratio of LC3 II/I, a marker of autophagy, and Atg5, Atg12 and Atg12-Atg5 conjugate proteins were increased in doxorubicin-treated mice, and the increases were attenuated by the GSK2795039 treatment. These findings suggest that inhibition of Nox2 by GSK2795039 attenuates cardiac sympathetic nerve terminal abnormalities and myocyte autophagy, thereby ameliorating cardiac atrophy and dysfunction after chronic doxorubicin treatment.

MiR-378 Inhibits Angiotensin II-Induced Cardiomyocyte Hypertrophy by Targeting AKT2

Cardiomyocyte hypertrophy plays a crucial role in heart failure development, potentially leading to sudden cardiac arrest and death. Previous studies suggest that micro-ribonucleic acids (miRNAs) show promise for the early diagnosis and treatment of cardiomyocyte hypertrophy.To investigate the miR-378 expression in the cardiomyocyte hypertrophy model, reverse transcription-polymerase chain reaction (RT-qPCR), Western blot, and immunofluorescence tests were conducted in angiotensin II (Ang II)-induced H9c2 cells and Ang II-induced mouse model of cardiomyocyte hypertrophy. The functional interaction between miR-378 and AKT2 was studied by dual-luciferase reporter, RNA pull-down, Western blot, and RT-qPCR assays.The results of RT-qPCR analysis showed the downregulated expression of miR-378 in both the cell and animal models of cardiomyocyte hypertrophy. It was observed that the introduction of the miR-378 mimic inhibited the hypertrophy of cardiomyocytes induced by Ang II. Furthermore, the co-transfection of AKT2 expression vector partially mitigated the negative impact of miR-378 overexpression on Ang II-induced cardiomyocytes. Molecular investigations provided evidence that miR-378 negatively regulated AKT2 expression by interacting with the 3' untranslated region (UTR) of AKT2 mRNA.Decreased miR-378 expression and AKT2 activation are linked to Ang II-induced cardiomyocyte hypertrophy. Targeting miR-378/AKT2 axis offers therapeutic opportunity to alleviate cardiomyocyte hypertrophy.

RING Finger Protein 10 Regulates AP-1/Meox2 to Mediate Pirarubicin-Induced Cardiomyocyte Apoptosis

Pirarubicin (THP) is one of the classic chemotherapy drugs for cancer treatment. It is often clinically limited because of its cardiotoxicity. The occurrence and development of THP-mediated chemotherapy-related cardiotoxicity (CRC) may be reversed by RING finger protein 10 (RNF10). This study was performed with the aim of evaluating the inhibitory effect of RNF10 on THP-mediated CRC and its molecular mechanism. In vivo, we found that the expression of RNF10 decreased in THP-induced CRC rats, accompanied by Meox2 inhibition and AP-1 activation, resulting in increased cardiomyocyte apoptosis. After small interfering RNA (siRNA) and lentivirus transfection (Lv) of RNF10 in vitro, the expression of RNF10, Meox2, and AP-1 proteins and the degree of cardiomyocyte apoptosis were detected. We found that overexpression of RNF10 in H9C2 cardiomyocytes significantly promoted Meox2 and inhibited AP-1, alleviated apoptosis, and showed further inhibitory activity on THP-induced cardiomyocyte toxicity. Silencing RNF10 showed the opposite result. Our study showed that RNF10 inhibited THP-induced CRC through the activity of Meox2 and AP-1 proteins. RNF10 may be the next drug target for the treatment of CRC and other related cardiovascular diseases.

Left Ventricular Assist Device Implantation in Cancer-Therapy-Related Heart Failure

Objectives: Cancer-therapy-related heart failure (CTrHF) due to cardiotoxic drugs or radiation is a growing cause of end-stage heart failure. Limited knowledge is available concerning the use of continuous-flow left-ventricular-assist devices (cfLVAD) in this setting. Methods: The files of all 1334 patients who underwent cfLVAD implantation between December 2008 and December 2020 were screened for the cause of heart failure. All patients with CTrHF were included in the analysis. Results: A total of 32 patients with a median age of 58 years (IQR: 46–65) were included in the study; 15 (47%) were male. The median time from the first diagnosis of heart failure (HF) to cfLVAD implantation was 6 months (IQR 2–24), and from cancer treatment to cfLVAD implantation 40 months (IQR 5–144). Malignancies comprised non-Hodgkin lymphoma (n = 12, 37%), breast cancer (n = 9, 28%), sarcoma (n = 5, 16%), leukemia (n = 5, 16%), and others (n = 1, 3%). In 24 patients, chemotherapy included anthracyclines (others n = 2, unknown n = 6). Chest radiation was performed in 13 patients (39%). Moreover, 71% were classified as INTERMACS profile 1 or 2. The 30-day survival rate after LVAD implantation was 88%. Rethoracotomy was necessary in nine (29%), and a temporary right ventricular assist device in seven (21%) patients. The median survival was 29 months. There was no significant difference in survival or right HF between patients with CTrHF and a matched control group. Conclusions: CfLVAD implantation is feasible in high-risk patients with CTrHF with or without prior chest radiation.

Neurotoxic Effect of Doxorubicin Treatment on Cardiac Sympathetic Neurons

Doxorubicin (DOXO) remains amongst the most commonly used anti-cancer agents for the treatment of solid tumors, lymphomas, and leukemias. However, its clinical use is hampered by cardiotoxicity, characterized by heart failure and arrhythmias, which may require chemotherapy interruption, with devastating consequences on patient survival and quality of life. Although the adverse cardiac effects of DOXO are consolidated, the underlying mechanisms are still incompletely understood. It was previously shown that DOXO leads to proteotoxic cardiomyocyte (CM) death and myocardial fibrosis, both mechanisms leading to mechanical and electrical dysfunction. While several works focused on CMs as the culprits of DOXO-induced arrhythmias and heart failure, recent studies suggest that DOXO may also affect cardiac sympathetic neurons (cSNs), which would thus represent additional cells targeted in DOXO-cardiotoxicity. Confocal immunofluorescence and morphometric analyses revealed alterations in SN innervation density and topology in hearts from DOXO-treated mice, which was consistent with the reduced cardiotropic effect of adrenergic neurons in vivo. Ex vivo analyses suggested that DOXO-induced denervation may be linked to reduced neurotrophic input, which we have shown to rely on nerve growth factor, released from innervated CMs. Notably, similar alterations were observed in explanted hearts from DOXO-treated patients. Our data demonstrate that chemotherapy cardiotoxicity includes alterations in cardiac innervation, unveiling a previously unrecognized effect of DOXO on cardiac autonomic regulation, which is involved in both cardiac physiology and pathology, including heart failure and arrhythmias.

Polydopamine-doped supramolecular chiral hydrogels for postoperative tumor recurrence inhibition and simultaneously enhanced wound repair

Cancer recurrence remains a major challenge after primary tumor excision, and the inflammation of tumor-caused wounds can hinder wound healing and potentially promote tumor growth. Herein, a chiral L-phenylalanine-based (LPFEG) supramolecular hydrogel system encapsulated with polydopamine nanoparticles (PDA-NPs) has been developed in order to prevent tumor relapse after surgery and promote wound repair. PDA-NPs allow for near-infrared (NIR) light-triggered photothermal therapy, especially, it can scavenge free radicals in the surgical wound. LPFEG can mimic native extracellular matrix (ECM) structure to create a chiral microenvironment that enhances fibroblast adhesion, proliferation, and new tissue regeneration. With anticancer drug doxorubicin (DOX) loaded into the composite hydrogel, the antitumor effect is significantly enhanced by the integration of chemo-photothermal therapy both in vitro and in vivo. The PDA-based chiral supramolecular composite hydrogel as an effective postoperative adjuvant possesses promising applicable prospects in inhibiting tumor recurrence and accelerating wound healing after operation. STATEMENT OF SIGNIFICANCE: After primary tumor excision, cancer recurrence remains a severe concern, and the inflammation induced by tumor-related wounds can delay wound healing. Herein, we designed a chiral L-phenylalanine-based (LPFEG) supramolecular hydrogel platform that was co-assembled with polydopamine nanoparticles (PDA-NPs). Among them, PDA-NPs can offer photothermal therapy and scavenge free radicals in surgical wounds. LPFEG can create a chiral microenvironment that promotes fibroblast adhesion, proliferation, and new tissue regeneration. Furthermore, with anticancer drug doxorubicin (DOX) loaded into the composite hydrogel, the antitumor effect is considerably boosted. Therefore, the PDA-based chiral supramolecular hydrogel shows high application potential as a postoperative adjuvant in preventing tumor relapse as well as accelerating wound healing after surgery.

Ventricular assist device support for children with chemotherapy-induced cardiomyopathy and advanced heart failure: Perspectives gained from a single-center experience

BACKGROUND

Guidance and data on ventricular assist device (VAD) support for children with chemotherapy-induced cardiomyopathy, particularly within the first 2 years after chemotherapy, are limited.

METHODS

We performed a single-center retrospective case series, reviewing medical records of children <18 years of age with chemotherapy-induced cardiomyopathy and advanced heart failure (HF) who received durable VAD support.

RESULTS

Six patients met inclusion criteria-5 HeartWare™ HVAD, 1 Berlin Heart EXCOR^® . Median age at cancer diagnosis was 6 years (IQR 4.5-10 years). Median dose of anthracycline received was 540 mg/m² (IQR 450-630 mg/m² ). All patients developed HF within 1 year after initiation of cancer treatment (median 8 months, IQR 6-11.5 months) and were initiated on durable VAD support at a median of 8 months after completion of cancer treatment (IQR 3.3-43.5 months). Four patients had significant right ventricular dysfunction needing oral pulmonary vasodilator therapy, one patient had a major bleeding complication, and two patients had thromboembolic strokes while on VAD support. Median duration of VAD support was 7.5 months (IQR 3-11.3 months). Two patients underwent VAD explant due to recovery of LV function, one died due to cancer progression, and three underwent heart transplantation.

CONCLUSIONS

Durable VAD support should be considered as a therapeutic option for children who have advanced HF due to chemotherapy-induced cardiomyopathy, even within 2 years of completing cancer treatment. A multi-disciplinary approach is essential for appropriate patient selection prior to implant and to ensure comprehensive care throughout the duration of VAD support.

Management of Advanced Heart Failure in Children with Cancer Therapy-Related Cardiac Dysfunction

The evolution of cancer therapies has led to marked improvement in survival of those affected by childhood malignancies, while also increasing the recognition of early and late toxicities associated with cancer therapies. Cardiotoxicity can include cardiomyopathy/heart failure, coronary artery disease, stroke, pericardial disease, arrhythmias, and valvular and vascular dysfunction as a result of exposure to chemotherapy and/or radiation. Anthracyclines remain the most common cause of chemotherapy-induced cardiomyopathy (CCM) with varying clinical presentations including: acute, early onset, and late-onset. Many individuals develop cardiac dysfunction over the long-term, ranging from subclinical cardiac dysfunction to end-stage symptomatic heart failure. The focus of this review is on characterization of symptomatic heart failure in children with cancer therapy-related cardiac dysfunction (CTRCD) primarily due to CCM and utilization of advanced heart failure therapies, including ventricular assist device (VAD) support and heart transplantation, with consideration of unique patient-related factors.

Heart Transplantation in Adriamycin-Associated Cardiomyopathy in the Contemporary Era of Advanced Heart Failure Therapies

Background

Adriamycin-associated cardiomyopathy (ACM) can lead to end-stage heart failure requiring advanced heart failure therapies.

Objectives

This study sought to provide post-cardiac transplant survival data in patients with ACM in the contemporary era of mechanical circulatory support and cardiac transplantation.

Methods

Adults (≥18 years of age) who underwent first-time, single-organ heart transplantation were identified from the United Network for Organ Sharing between October 18, 2008, and October 18, 2018. Cardiomyopathy subtypes that could have been supported with a left ventricular assist device (LVAD) including ACM, dilated cardiomyopathy (DCM), and ischemic cardiomyopathy (ICM) were included. A multivariable Cox regression analysis was performed to determine the association between cardiomyopathy subtype and post-cardiac transplant survival.

Results

This analysis included 18,270 patients (357 with ACM; 10,662 with DCM; and 7,251 with ICM). Heart transplant recipients with ACM were younger, included more women, and had higher pulmonary vascular resistance at the time of listing. Patients with ACM had a lower percentage of durable LVADs at the time of transplant across all years of the study period. Patients with ACM did not experience an increase in post-cardiac transplant mortality compared to those with DCM (adjusted hazard ratio: 0.96; 95% confidence interval: 0.79 to 1.40; p = 0.764) or ICM (adjusted hazard ratio: 0.85; 95% confidence interval: 0.6 to 1.2; p = 0.304).

Conclusions

Patients with ACM who received heart transplants between 2008 and 2018 had similar post-cardiac transplant survival to those with dilated and ischemic cardiomyopathy. Bridge-to-transplant LVAD use remains lower compared to other cardiomyopathy subtypes.

Successful Heart Transplant in a Childhood Cancer Survivor With Chemoradiotherapy-Induced Cardiomyopathy

Cancer therapy-related cardiotoxicity has been presenting a major problem in cancer survivors, who constitute a growing population caused by a significant improvement in cancer therapy during the past decades. Although some listing criteria have been defined for these patients, it is still a compelling decision to list patients with a complex cancer anamnesis. We describe herein a childhood cancer survivor after a cancer anamnesis with 2 different malignancies and an end-stage heart failure following chemoradiotherapy who was successfully treated with orthotopic heart transplant.

Cardiac Interventional Procedures in Cardio-Oncology Patients

Comorbidities specific to the cardio-oncology population contribute to the challenges in the interventional management of patients with cancer and cardiovascular disease (CVD). Patients with cancer have generally been excluded from cardiovascular randomized clinical trials. Endovascular procedures may represent a valid option in patients with cancer with a range of CVDs because of their minimally invasive nature. Patients with cancer are less likely to be treated according to societal guidelines because of perceived high risk. This article presents the specific challenges that interventional cardiologists face when caring for patients with cancer and the modern tools to optimize care.

Doxorubicin Exposure Causes Subacute Cardiac Atrophy Dependent on the Striated Muscle-Specific Ubiquitin Ligase MuRF1

Background Anthracycline chemotherapeutics, such as doxorubicin, are used widely in the treatment of numerous malignancies. The primary dose-limiting adverse effect of anthracyclines is cardiotoxicity that often presents as heart failure due to dilated cardiomyopathy years after anthracycline exposure. Recent data from animal studies indicate that anthracyclines cause cardiac atrophy. The timing of onset and underlying mechanisms are not well defined, and the relevance of these findings to human disease is unclear. Methods and Results Wild-type mice were sacrificed 1 week after intraperitoneal administration of doxorubicin (1-25 mg/kg), revealing a dose-dependent decrease in cardiac mass ( R2=0.64; P<0.0001) and a significant decrease in cardiomyocyte cross-sectional area (336±29 versus 188±14 µm2; P<0.0001). Myocardial tissue analysis identified a dose-dependent upregulation of the ubiquitin ligase, MuRF1 (muscle ring finger-1; R2=0.91; P=0.003) and a molecular profile of muscle atrophy. To investigate the determinants of doxorubicin-induced cardiac atrophy, we administered doxorubicin 20 mg/kg to mice lacking MuRF1 (MuRF1-/-) and wild-type littermates. MuRF1-/- mice were protected from cardiac atrophy and exhibited no reduction in contractile function. To explore the clinical relevance of these findings, we analyzed cardiac magnetic resonance imaging data from 70 patients in the DETECT-1 cohort and found that anthracycline exposure was associated with decreased cardiac mass evident within 1 month and persisting to 6 months after initiation. Conclusions Doxorubicin causes a subacute decrease in cardiac mass in both mice and humans. In mice, doxorubicin-induced cardiac atrophy is dependent on MuRF1. These findings suggest that therapies directed at preventing or reversing cardiac atrophy might preserve the cardiac function of cancer patients receiving anthracyclines.

MicroRNA-375-3p inhibitor suppresses angiotensin II-induced cardiomyocyte hypertrophy by promoting lactate dehydrogenase B expression

Cardiac hypertrophy is a myocardial enlargement due to overload pressure, and the primary cause of heart failure. We investigated the function of miR-375-3p in cardiac hypertrophy and its regulating mechanisms. miR-375-3p was upregulated in hearts of the transverse aortic constriction rat model and angiotensin II (Ang II)-induced primary cardiomyocyte hypertrophy model; the opposite was observed for lactate dehydrogenase B (LDHB) protein expression. miR-375-3p knockdown reduced the surface area of primary cardiomyocytes increased by Ang II treatment and decreased the B-natriuretic peptide (BNP) and β-myosin heavy chain (β-MHC) messenger RNA (mRNA) and protein levels. miR-375-3p was also observed to directly target LDHB. LDHB knockdown increased the surface area of Ang II-treated primary cardiomyocytes and increased the BNP and β-MHC mRNA and protein levels. LDHB knockdown attenuated the effects of miR-375-3p on the surface area of primary cardiomyocytes and BNP and β-MHC levels. Therefore, miR-375-3p inhibitor suppresses Ang II-induced cardiomyocyte hypertrophy by promoting LDHB expression.

Risk of regorafenib-induced cardiovascular events in patients with solid tumors: A systematic review and meta-analysis

BACKGROUND

The present comparative meta-analysis was conducted to evaluate the cardiovascular events of regorafenib in patients with solid tumors.

METHODS

Eligible studies from MEDLINE, Google Scholar, Cochrane Library, Clinical key, EBSCO publishing and Ovid, which had reported cardiovascular adverse events potentially caused by regorafenib were absorbed. Data of clinical characteristics and cardiovascular events including hypertension, hemorrhage, thrombosis, and heart failure were extracted from selected literatures for the final analysis. Pooled analysis of cardiovascular adverse events was developed by relative risks (RRs) and corresponding 95% confidence intervals (CIs) with software STATA 13.0 and RevMan 5.3.

RESULTS

Thirty studies including 3813 patients were fit into analysis. The incidences of cardiovascular events of all-grade were: hypertension, 36.8% (95% CI, 29.8%-43.8%), hemorrhage, 8.6% (95% CI, 3.2%-14%), thrombosis, 1.4% (95% CI, 0.1%-2.8%), and heart failure, 2.9% (95% CI, 0.3%-5.6%). The incidences of cardiovascular events of high-grade were: hypertension, 9.9% (95% CI, 7.4%-12.4%), hemorrhage, 1.2% (95% CI, 0.3%-2.2%), thrombosis, 1.6% (95% CI, 0.2%-3.4%), and heart failure, 2.9% (95% CI, 0.3%-5.6%). The RRs and their 95% CIs of all-grade cardiovascular events among patients treated with regorafenib were: hypertension, 4.10 (95% CI, 3.07-5.46; P < .00001), hemorrhage, 2.71 (95% CI, 1.45-5.08; P = .002), thrombosis, 1.27 (95% CI, 0.49-3.27; P = .62), and heart failure, 0.79 (95% CI, 0.16-3.94; P = .77). The RRs and their 95% CIs of high-grade cardiovascular events among patients treated with regorafenib were: hypertension, 5.82 (95% CI, 3.46-9.78; P < .00001), hemorrhage, 0.90 (95% CI, 0.50-1.61; P = .72), thrombosis, 1.28 (95% CI, 0.48-3.41; P = .62), and heart failure, 1.15 (95% CI, 0.23-5.69; P = .86), respectively.

CONCLUSION

The present meta-analysis has demonstrated that regorafenib is associated with an increasing risk of hypertension at all-grade and high-grade, as well as hemorrhage at all-grade. Adequate awareness of cardiovascular adverse events of regorafenib should be established for clinicians.

Cardiovascular safety of oncologic agents: a double-edged sword even in the era of targeted therapies - Part 2

INTRODUCTION

Patients with cancer are subject to the cardiotoxic effects of cancer therapy. Improved cancer treatments lead to more cancer-survivors, who though are exposed to various forms of cardiovascular (CV) disease (CVD) as they age. Aging patients are at increased risk of developing both malignancy and CVD or they may have survived some form of CVD as a result of effective CV treatments. Furthermore, patients with CVD may develop cancer and require treatment (and vice versa), all contributing to increased morbidity and mortality. The prevalence of both malignancy and CVD will increase due to the trend toward a longer lifespan.

AREAS COVERED

In part 2 of this review, the discussion of the CV effects of specific oncology drugs is completed with inclusion of additional immunological agents, current hormonal and other agents. Early detection and monitoring of cardiotoxicity, use of biomarkers and other imaging and diagnostic methods and prevention and treatment options are also discussed.

EXPERT OPINION

As outlined in part 1 of this review, oncologists need to be aware of the CV adverse-effects of their treatments and make careful and expectant clinical decisions, especially in patients with preexisting CVD or CV risk factors. Similarly, cardiologists should consider a detailed previous history of treatment for malignant disease, including prior chemotherapy exposure, dose(s) received, and/or combined modality therapy with chest radiotherapy. Both specialists should collaborate in order to minimize the impact of these two ubiquitous diseases (cancer and CVD) and mitigate the adverse effects of treatment modalities.

Antitumor Effect by Hydroxyapatite Nanospheres: Activation of Mitochondria-Dependent Apoptosis and Negative Regulation of Phosphatidylinositol-3-Kinase/Protein Kinase B Pathway

Hydroxyapatite nanoparticles (HA NPs) have been acknowledged for their benign biocompatibility and proliferation inhibition effect on tumor cells, attracting considerable attention for tumor therapeutics without late effects. However, unnoticeable tumor cytotoxicity of HA NPs limited the final clinical therapeutic efficacy. Herein, a two-phase synthetic approach was developed to synthesize sphere-like HA NPs by varying the conventional growth habit of HA precipitate. We present our in vitro and in vivo experimental evidence that spherical HA NPs have surprisingly high inhibitory activities against tumor cells. We demonstrate further, based on our experimental data, that the underlying cause for the death of the tumor cells is related to two concurrent pathways, the mitochondria-dependent apoptosis pathway and negative regulation of the phosphatidylinositol-3-kinase/protein kinase B (PIK3/AKT) pathway. The present study indicated that HA nanospheres can be engineered as nontoxic specific inhibitors for efficient tumor therapeutics with nanobiomaterials.

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.

Comparison of long-term outcome in anthracycline-related versus idiopathic dilated cardiomyopathy: a single centre experience

AIMS

Cardiac dysfunction is a severe complication of anthracycline-containing anticancer therapy. The outcome of anthracycline-induced cardiomyopathy (AICM) compared with other non-ischaemic causes of heart failure (HF), such as idiopathic dilated cardiomyopathy (IDCM), is unresolved. The aim of this study was to compare the survival of AICM patients with an IDCM cohort followed at our centre from 1990 to 2016.

METHODS AND RESULTS

We included 67 patients (67% female, 50 ± 15 years) with AICM, defined as onset of otherwise unexplained left ventricular ejection fraction (LVEF) ≤50% following anthracycline therapy, and 488 IDCM patients (28% female, 55 ± 12 years). Patients were followed with constantly optimized HF therapy, for 7.6 ± 5.5 and 8.1 ± 5.5 years, respectively. In both cohorts, 25% of patients reached the combined endpoint of death/heart transplantation. Overall survival rates at 5 and 10 years were similar (AICM: 86% and 61%, IDCM: 88% and 75%; P = 0.61), and so was cardiovascular survival (AICM: 91% and 76%, IDCM: 91% and 80%; P = 0.373), also after 1:1 propensity matching (P = 0.27) and adjusting for age, LVEF and left ventricular size. A trend toward higher all-cause mortality was present in AICM patients [hazard ratio (HR) 1.67, 95% confidence interval (CI) 0.95-2.92, P = 0.076]. No differences were observed between AICM and IDCM with regard to pharmacological HF therapy, but AICM patients were less likely to receive devices (13% vs. 41.8% in IDCM, P < 0.001).

CONCLUSION

Cardiovascular mortality in patients with AICM did not differ from that of a matched IDCM cohort, despite cancer-related morbidity and less prevalent use of devices. These data suggest that patients with AICM should be treated with appropriate guideline-directed medical therapies similar to other non-ischaemic dilated cardiomyopathies.

The Initial Evaluation and Management of a Patient with Heart Failure

PURPOSE OF REVIEW

The goal of this review is to summarize and discuss a thorough and effective manner in the evaluation of the patient with heart failure.

RECENT FINDINGS

Heart failure is a prevalent disease worldwide and while the diagnosis of heart failure has remained relatively unchanged via a careful history and physical examination, identification of the etiology of the heart failure and treatment has made significant advances. Mechanical circulatory support (MCS), neprilysin inhibitors, and chronic resynchronization therapy (CRT) are just some of the relatively recent therapies afforded to assist heart failure patients. Heart failure is a complicated, multifactorial diagnosis that requires a careful history and physical for diagnosis with the support of laboratory tests. While the prognosis for heart failure patients remains poor in comparison to other cardiovascular disease and even certain cancers, new advancements in therapy have shown survival and quality of life improvement.

Incidence, Diagnosis, and Treatment of Cardiac Toxicity from Trastuzumab in Patients with Breast Cancer

PURPOSE OF REVIEW

Treatment with trastuzumab is a cornerstone of human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer treatment, but carries an unfortunate risk of toxicity to the cardiovascular system. Here we review recent findings on trastuzumab-associated cardiotoxicity, focusing on its incidence, diagnosis, and treatment.

RECENT FINDINGS

Screening with multigated acquisition scan (MUGA) or echocardiogram (ECHO) is recommended to assess cardiac function prior to and during trastuzumab therapy. Because trastuzumab-induced cardiotoxicity is typically reversible, cessation of trastuzumab and/or administration of first line heart failure agents effectively restores cardiac function in most cases. Severe trastuzumab-induced cardiotoxicity is rare enough that the risk-benefit ratio still weighs in favor of its use in the vast majority of patients with HER2+ breast cancer.

SUMMARY

An improved understanding of the pathophysiology underlying trastuzumab-induced cardiotoxicity and the identification of patients at highest risk will allow us to continue to safely administer trastuzumab in patients with breast cancer.

MicroRNA-497 Inhibits Cardiac Hypertrophy by Targeting Sirt4

Cardiac hypertrophy is an adaptive enlargement of the myocardium in response to overload pressure of heart. From abundant studies, a conclusion is drawn that many microRNAs (miRNAs) are associated with cardiac hypertrophy and heart failure. To investigate the role of microRNA-497 (miR-497) in myocardial hypertrophy, two models were established in this study from cell level to integral level. Cardiac hypertrophy was induced by using angiotensin Ⅱ (Ang Ⅱ) in vitro and was created by transverse abdominal aortic constriction (TAC) in vivo. There was a significant decrease expression of miR-497 in cardiac hypertrophy models. Moreover, overexpression of miR-497 inhibited myocardial hypertrophy both in vitro and in vivo without heart function variation. In addition, luciferase reporter assays demonstrated that Sirt4 was a direct target gene of miR-497. Taking together, our study indicates that miR-497 modulates cardiac hypertrophy by targeting Sirt4 and may serve as a potential therapeutic substance in the course.