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

Management of Cancer Therapy-Related Cardiac Dysfunction: A Case-Based Review

With an ever-expanding repertoire of cancer therapies, cardiologists increasingly encounter patients with cancer therapy-related cardiac dysfunction. This can range from asymptomatic mild left ventricular dysfunction to severe symptomatic congestive heart failure. A multidisciplinary approach involving oncologists and cardiologists is needed in the management of these patients. This case-based review provides a practical guide for clinicians regarding the diagnosis and management of cancer therapy-related cardiac dysfunction associated with commonly used cancer treatments: anthracyclines, human epidermal receptor 2-targeted therapies, and immune checkpoint inhibitors.

Cardiac Dysfunction Among Breast Cancer Survivors: Role of Cardiotoxic Therapy and Cardiovascular Risk Factors

PURPOSE

Cardiac dysfunction is the leading cause of mortality among 10-year breast cancer survivors. Limited information regarding long-term risks of cardiac dysfunction after cardiotoxic therapy (anthracyclines, trastuzumab/pertuzumab, radiation) has precluded development of surveillance guidelines for the survivors.

METHODS

Patients with breast cancer who completed cardiotoxic therapy underwent echocardiographic screening every 2 years. New-onset cardiac dysfunction was defined as left ventricular ejection fraction (LVEF) <50% after cardiotoxic therapy initiation and included early- and late-onset cardiac dysfunction.

RESULTS

We evaluated 2,808 echocardiograms in 829 breast cancer survivors; the median age at breast cancer diagnosis was 54.2 years (range, 20.3-86.3); the median follow-up was 8.6 years (1.8-39.8); 39.7% received anthracyclines, 16% received trastuzumab/pertuzumab, 6.2% received both anthracyclines and trastuzumab/pertuzumab, and 38.1% received radiation alone. The cumulative incidence of cardiac dysfunction increased from 1.8% at 2 years to 15.3% at 15 years from cardiotoxic therapy initiation. Multivariable Cox regression analysis identified the following risk factors: non-Hispanic Black race (hazard ratio [HR], 2.15 [95% CI], 1.37 to 3.38), cardiotoxic therapies (anthracyclines: HR, 2.35 [95% CI, 1.25 to 4.4]; anthracyclines and trastuzumab/pertuzumab: HR, 3.92 [95% CI, 1.74 to 8.85]; reference: left breast radiation alone), selective estrogen receptor modulators (HR, 2.0 [95% CI, 1.2 to 3.33]), and precancer hypertension (HR, 3.16 [95% CI, 1.63 to 6.1]). Late-onset cardiac dysfunction was most prevalent among anthracycline- and radiation-exposed patients; early-onset cardiac dysfunction was most prevalent among patients exposed to anthracyclines and trastuzumab/pertuzumab; equal prevalence of both early- and late-onset cardiac dysfunction was observed in trastuzumab-/pertuzumab-exposed patients. Adjusted longitudinal analyses revealed an annual decline in LVEF by 0.29% (P = .009) over 20 years from breast cancer diagnosis.

CONCLUSION

These findings provide evidence to support echocardiographic surveillance for several years after cardiotoxic therapy and also suggest a need to examine the efficacy of management of cardiovascular risk factors to mitigate risk.

Late cardiotoxicity related to HER2-targeted cancer therapy

Long-term anti-HER2 therapy in metastatic HER2 + cancers is increasing, but data about the incidence and risk factors for developing late Cancer therapy-related cardiac dysfunction (CTRCD) are missing. We conducted a single-centre, retrospective analysis of a cohort of late anti-HER2 related cardiac dysfunction referred to our Cardio-Oncology service. We include seventeen patients with metastatic disease who developed CTRCD after at least five years of continuous anti-HER2 therapy. Events occurred after a median time of 6.5 years (IQR 5.3-9.0) on anti-HER2 therapy. The lowest (median) LVEF and GLS were 49% (IQR 45-55) and - 15.4% (IQR - 14.9 - -16.3) respectively. All our patients continued or restarted, after a brief interruption, their anti-HER2 therapy. Most (16/17) were started on heart failure medical therapy and normalized their left ventricular ejection fraction at a follow-up. Our study has demonstrated that CTRCD can occur after many years of stability on anti-HER2 therapy and reinforces the importance of continuing cardiovascular surveillance in this population.

Adjuvant Trastuzumab Emtansine Versus Paclitaxel and Trastuzumab in Stage I HER2-Positive Breast Cancer: The ATEMPT Trial

This ASO perspective reviews the findings of a randomized, phase II clinical trial evaluating adjuvant trastuzumab emtansine (T-DM1) compared with paclitaxel and trastuzumab (TH) in stage I human epidermal growth factor receptor 2-positive breast cancer, as reported recently by the ATEMPT trial investigators. Patients treated with T-DM1 had better disease-free survival but did not have fewer treatment toxicities. The T-DM1-treated group had higher rates of treatment discontinuations, therefore long-term follow-up will be required to evaluate survival differences between T-DM1 and TH.

Assessing Adherence to Cardiac Monitoring Guidelines in Trastuzumab-Treated Breast Cancer Patients: Insights From a Tertiary Hospital

INTRODUCTION

Breast cancer is a global health concern, with a significant portion of patients exhibiting human epidermal growth factor receptor 2 (HER2) overexpression. Trastuzumab is one of the pivotal therapies for HER2-positive breast cancer, but it carries the risk of cardiotoxicity. Guidelines for cardiac monitoring are essential to detect early signs of cardiotoxicity. However, adherence to these guidelines remains uncertain.

METHOD

In this single-center retrospective cohort study, we analyzed data from 167 female patients diagnosed with HER2-positive breast cancer who were treated with trastuzumab. We meticulously assessed the level of adherence to cardiac monitoring guidelines and determined the incidence of trastuzumab-induced cardiotoxicity (TIC). Factors affecting adherence were subsequently investigated using appropriate statistical methods.

RESULTS

Adherence to monitoring guidelines was only 31.7%. TIC incidence was 7.8%. Patients with concurrent use of cardiotoxic medications demonstrated higher adherence. A significant association was found between the number of trastuzumab doses and adherence.

CONCLUSION

Adherence to monitoring guidelines was suboptimal. Those at a higher risk of cardiac issues showed greater adherence. Improved risk assessment methods are needed to individualize monitoring and intervention. Future research should focus on patient-centered, evidence-based monitoring to optimize the balance between cancer therapy and cardiac safety in the field of cardio-oncology.

Dual-Targeted Therapy in HER2-Overexpressing Breast Cancer with Trastuzumab and Novel Cholesterol-Based Nioplexes Silencing Mcl-1

The challenge in HER2-overexpressing breast cancer therapy lies in creating an effective target therapy to overcome treatment resistance. Monoclonal antibodies and target gene silencing by siRNA are two potential strategies that have been widely developed for treating HER2-positive breast cancer. The siRNA delivery system is a crucial factor that influences siRNA therapy's success. In this study, lipid-based nanoparticles (cationic niosomes) composed of different cholesterol-based cationic lipids were formulated and characterized for delivering siRNA into HER2-overexpressing breast cancer cells. Niosomes containing a trimethylammonium headgroup showed the highest siRNA delivery efficiency with low toxicity. The myeloid cell leukemia-1 (Mcl-1) siRNA nioplex treatment significantly decreased mRNA expression and breast cancer cell growth. Dual-targeted therapy, consisting of treatment with an Mcl-1 siRNA nioplex and trastuzumab (TZ) solution, noticeably promoted cell-growth inhibition and apoptosis. The synergistic effect of dual therapy was also demonstrated by computer modeling software (CompuSyn version 1.0). These findings suggest that the developed cationic niosomes were effective nanocarriers for siRNA delivery in breast cancer cells. Furthermore, the Mcl-1 nioplex/TZ dual treatment establishes a synergistic outcome that may have the potential to treat HER2-overexpressing breast cancer.

Cancer Treatment-Related Cardiovascular Toxicity in Gynecologic Malignancies: JACC: CardioOncology State-of-the-Art Review

Improvements in early detection and treatment of gynecologic malignancies have led to an increasing number of survivors who are at risk of long-term cardiac complications from cancer treatment. Multimodality therapies for gynecologic malignancies, including conventional chemotherapy, targeted therapeutics, and hormonal agents, place patients at risk of cancer therapy-related cardiovascular toxicity during and following treatment. Although the cardiotoxicity associated with some female predominant cancers (eg, breast cancer) have been well recognized, there has been less recognition of the potential adverse cardiovascular effects of anticancer therapies used to treat gynecologic malignancies. In this review, the authors provide a comprehensive overview of the cancer therapeutic agents used in gynecologic malignancies, associated cardiovascular toxicities, risk factors for cardiotoxicity, cardiac imaging, and prevention strategies.

Association of Neurohormonal Antagonists on Incident Cardiotoxicity in Patients With Breast Cancer

Cardiovascular disease is the leading cause of mortality among breast cancer survivors. Anthracyclines and trastuzumab have been associated with an increased risk of cardiotoxicity, requiring close follow-up for signs of clinical heart failure or asymptomatic left ventricular systolic dysfunction. Whether neurohormonal antagonism with angiotensin-converting enzyme inhibitor (ACE-I), angiotensin receptor blockers (ARBs), or β-blockers can prevent the development of chemotherapy-induced cardiomyopathy in this population remains unknown. We studied 459 women who were diagnosed with breast cancer at our medical center from January 2014 to December 2021 and evaluated baseline characteristics, oncologic treatment, and outcomes. The primary end point was the development of cardiotoxicity, defined as symptomatic decline in ejection fraction of ≥5% below 55% or an asymptomatic decline of ≥10% after treatment with chemotherapy. Patients who were exposed to neurohormonal antagonists were more likely to have hypertension, hyperlipidemia, and diabetes. There was an increased risk of cardiotoxicity noted for patients who were older (hazard ratio [HR] 1.04, 95% confidence interval [CI] 1.01 to 1.1), smokers within the past 10 years (HR 2.54, 95% CI 1.41 to 4.6), or who received a combination of both trastuzumab and anthracycline therapy (HR 2.52, 95% CI 1.01 to 6.3). Over a median follow-up of 12 months, there were no significant protective benefits noted for patients who were taking ACE-I/ARBs (HR 0.49, 95% CI 0.17 to 1.4), β-blockers (HR 0.50, 95% CI 0.16 to 1.6), or both (HR 1.30, 95% CI 0.44 to 3.9). In conclusion, previous use of ACE-I/ARBs and β-blockers, separately or in combination, was not associated with a reduction in the development of cardiotoxicity in patients receiving anthracycline or trastuzumab therapies. Older age, smoking, and combination chemotherapy were found to be associated with an increased risk.

New Concepts in Cardio-Oncology

Cancer and cardiovascular disease are the two major causes of morbidity and mortality in worldwide. Discovering new therapeutic agents for the management of breast cancer (BC) has increased the numbers of cancer survivors but with the risk of cardiovascular adverse events (CV-AEs). All drugs can potentially damage the cardiovascular system, with different types of clinical manifestations from ischemic myocardial disease to vasculitis, thrombosis or pericarditis. An early detection of CV-AEs guarantees an earlier treatment, which is associated with better outcomes. Cardio-oncology field enlarged its studies to improve prevention, monitoring and treatment of all cardiotoxic manifestations related to old or modern oncological agents. A multidisciplinary approach with a close partnership between oncologists and cardiologists is essential for an optimal management and therapeutic decision-making. The aim of this chapter is to review all types of cardiotoxic manifestations related to novel and old agents approved for treatment of BC patients including chemotherapy, anti-HER2 agents, cyclin-dependent kinase 4/6 inhibitors, PolyADP-ribose polymerase (PARP) inhibitors, antiangiogenic drugs and immunotherapy. We also focused our discussion on prevention, monitoring, treatment, and management of CV-AEs.

The association of trastuzumab with atrial fibrillation and heart failure in breast cancer patients in routine clinical practice: a population-based propensity score matching and competing risk model analysis

PURPOSE

Trastuzumab, a potent anti-human epidermal growth factor receptor 2 (HER2) monoclonal antibody, is conditionally reimbursed by the Taiwan National Health Insurance (NHI) for HER2-positive breast cancer (BC). Trastuzumab-induced cardiotoxicity studies have well characterized heart failure (HF) but fewer addressed arrhythmia, particularly the association of potential life threatening atrial fibrillation (Af) is poorly characterized. We aimed to study the trastuzumab-related risk of Af and HF using the claimed data of Taiwan NHI.

METHODS

A nationwide retrospective cohort of patients with BC from the Taiwan NHI reimbursement database from January 2007 to December 2016 was analyzed. Propensity score matching and competing risk model analysis were used for adjusting confounding concurrent medication or comorbidities and competing events. The HF study was used to validate the method used.

RESULTS

For Af, 12,472 trastuzumab users were matched with 12,472 non-trastuzumab users. For HF, 12,241 trastuzumab users and 12,241 non-users were enrolled. We found that trastuzumab users had significantly worse HF-free survival but not Af-free survival than non-trastuzumab users. In the competing risk analysis, the use of trastuzumab did not increase the risk of Af (hazard ratio [HR] 0.76, P = 0.0006) but was associated with HF (HR 1.19, P = 0.0052). The risk trends among stratifications by comorbidities and concurrent medication remained in similar directions for both Af and HF.

CONCLUSION

Trastuzumab in real-world practice was associated with an increased risk of HF, but was not associated with an increased risk of Af in BC patients. Trastuzumab-induced arrhythmogenic effects may be masked by concurrent heart-protecting measures, more prominent roles of comorbidities or concurrent medications under real-world settings. Further studies are required.

Diastolic heart failure is a new clinical entity of trastuzumab-induced cardiotoxicity: a case report

Background

Cancer therapy-related cardiac dysfunction (CTRCD) is defined as a decrease in the left ventricular ejection fraction (LVEF) of >10% to a value below the lower limit of normal or relative reduction in global longitudinal strain (GLS) >15% from baseline after cancer treatment. However, the possibility of the development of isolated diastolic dysfunction has never been considered in the clinical presentation of CTRCD.

Case summary

An 81-year-old woman was admitted to our institution presenting with prominent bilateral leg oedema, orthopnoea, and 8 kg of weight gain after administration of the anti-human epidermal growth factor receptor 2 (HER-2) antibody, trastuzumab, for HER-2-positive breast cancer. Transthoracic echocardiography showed a preserved LVEF of 62% without a significant reduction in GLS compared with results obtained before anti-HER-2 targeted therapy. Doppler echocardiography distinctly revealed a newly developed significant left ventricular diastolic dysfunction with evidence of elevated filling pressure. After successful achievement of volume reduction, the patient underwent cardiac catheter examination, revealing an elevated pulmonary artery wedge pressure of 18 mmHg. Subsequently, trastuzumab was discontinued and the patient was treated with diuretics, arteriodilators, and venodilators, until the signs and symptoms of heart failure completely disappeared.

Discussion

In the management of CTRCD, including pretreatment screening, cardiotoxicity monitoring, follow-up after anti-cancer agents, and evaluation of the effectiveness of the therapy, too much emphasis has been paid exclusively to the development of systolic dysfunction; however, perspectives for diastolic dysfunction may be needed. A comprehensive multidisciplinary team approach composed of breast surgeons, oncologists, onco-cardiologists, and echocardiography specialists is required.

Cardiovascular Health Among Cancer Survivors. From the 2019 Behavioral Risk Factor Surveillance System Survey

With increasing prevalence, there is a growing population living with cardiovascular (CV) disease and cancer who are concurrently or at risk for developing these 2 disease states. We examined CV conditions and CV risk factors in cancer survivors in a cross-sectional analysis, using data from the 2019 Behavioral Risk Factor Surveillance System. Cancer survivors are more likely than participants without a cancer history to have multiple risk factors that increase their risk for CV disease and other chronic illnesses, including cigarette smoking, physical inactivity, and obesity. In contrast, cancer survivors are less likely to be heavy drinkers or to not consume fruits and vegetables. The odds of having a heart attack, coronary heart disease (CHD), diabetes, and hypertension were generally higher among cancer survivors. In multivariable analysis, the adjusted odds of having a heart attack, CHD, diabetes, hypertension, or high cholesterol were higher among cancer survivors than among participants without a history of cancer. Although the odds of obesity and physical inactivity were generally higher among cancer survivors across all socioeconomic status groups, the odds of having a heart attack or CHD were particularly high among Black and Hispanic cancer survivors and among younger participants. The odds of having diabetes were also higher among Black and Hispanic cancer survivors. In conclusion, cancer survivors are more likely than participants without a cancer history to have multiple risk factors that increase their risk of CV disease and other chronic illnesses, and they have a higher prevalence of heart attack, CHD, diabetes, and hypertension. Of particular concern are the higher prevalence of heart attack, CHD, and diabetes among Black and Hispanic cancer survivors.

Protective Effect of Curcumin, Chrysin and Thymoquinone Injection on Trastuzumab-Induced Cardiotoxicity via Mitochondrial Protection

Mitochondrial dysfunction may lead to cardiomyocyte death in trastuzumab (TZM)-induced cardiotoxicity. Accordingly, this study was designed to evaluate the mitochondrial protective effects of curcumin, chrysin and thymoquinone alone in TZM-induced cardiotoxicity in the rats. Forty-eight male adult Wistar rats were divided into eight groups: control group (normal saline), TZM group (2.5 mg/kg I.P. injection, daily), TZM + curcumin group (10 mg/kg, I.P. injection, daily), TZM + chrysin (10 mg/kg, I.P. injection, daily), TZM + thymoquinone (0.5 mg/kg, I.P. injection, daily), curcumin group (10 mg/kg, I.P. injection, daily), chrysin group (10 mg/kg, I.P. injection, daily) and thymoquinone group (10 mg/kg, I.P. injection, daily). Blood and tissue were collected on day 11 and used for assessment of creatine phosphokinase, lactate dehydrogenase (LDH), troponin, malondialdehyde (MDA) amount, glutathione levels and mitochondrial toxicity parameters. TZM increased mitochondrial impairments (reactive oxygen species formation, mitochondrial swelling, mitochondrial membrane potential collapse and decline in succinate dehydrogenase activity) and histopathological alterations (hypertrophy, enlarged cell, disarrangement, myocytes degeneration, infiltration of fat in some areas, hemorrhage and focal vascular thrombosis) in rat heart. As well as TZM produced a significant increase in the level of CK, LDH, troponin, MDA, glutathione disulfide. In most experiments, the co-injection of curcumin, chrysin and thymoquinone with TZM restored the level of CK, LDH, troponin, MDA, GSH, mitochondrial impairments and histopathological alterations. The study revealed the cardioprotective effects of curcumin, chrysin and thymoquinone against TZM-induced cardiotoxicity which could be attributed to their antioxidant and mitochondrial protection activities.

PET Tracers for Imaging Cardiac Function in Cardio-oncology

PURPOSE OF REVIEW

Successful treatment of cancer can be hampered by the attendant risk of cardiotoxicity, manifesting as cardiomyopathy, left ventricle systolic dysfunction and, in some cases, heart failure. This risk can be mitigated if the injury to the heart is detected before the onset to irreversible cardiac impairment. The gold standard for cardiac imaging in cardio-oncology is echocardiography. Despite improvements in the application of this modality, it is not typically sensitive to sub-clinical or early-stage dysfunction. We identify in this review some emerging tracers for detecting incipient cardiotoxicity by positron emission tomography (PET).

RECENT FINDINGS

Vectors labeled with positron-emitting radionuclides (e.g., carbon-11, fluorine-18, gallium-68) are now available to study cardiac function, metabolism, and tissue repair in preclinical models. Many of these probes are highly sensitive to early damage, thereby potentially addressing the limitations of current imaging approaches, and show promise in preliminary clinical evaluations. The overlapping pathophysiology between cardiotoxicity and heart failure significantly expands the number of imaging tools available to cardio-oncology. This is highlighted by the emergence of radiolabeled probes targeting fibroblast activation protein (FAP) for sensitive detection of dysregulated healing process that underpins adverse cardiac remodeling. The growth of PET scanner technology also creates an opportunity for a renaissance in metabolic imaging in cardio-oncology research.

Commentary: Cancer Survivorship and Subclinical Myocardial Damage

The rate of cardiovascular disease among cancer survivors is higher than in the general population. This difference is due to traditional cardiovascular disease (CVD) risk factors and also to the cardiotoxicity of cancer treatment. In a population-based cohort study of 3,512 men and women who were free of CVD at visit 5 of a large, community-based cohort study, Florido et al. (Am J Epidemiol. 2019;188(12):2188-2195) evaluated the association of cancer survivorship with subclinical myocardial damage, as assessed by elevated high-sensitivity cardiac troponin T (hs-cTnT). Cancer survivors had significantly higher odds of elevated hs-cTnT (odds ratio = 1.26, 95% confidence interval: 1.03, 1.53). Results were similar for survivors of non-sex-related and colorectal cancers. There was no association between survivorship from breast and prostate cancers and elevated hs-cTnT. The findings of Florido et al. indicate that survivors of some cancers might be more likely to have elevated hs-cTnT than patients without prior cancer. These findings have important implications because identifying cancer survivors who have elevated CVD risk is of paramount importance in order to prevent CVD manifestations such as heart attack, congestive heart failure, or stroke. Additional research is needed to clarify the associations of elevated hs-cTnT levels among survivors of specific cancer sites, stage at diagnosis, and histologic types.

Trastuzumab tolerability in the treatment of advanced (stage III-IV) or recurrent uterine serous carcinomas that overexpress HER2/neu

OBJECTIVE

Due to previously reported trastuzumab safety concerns and the scant data available in endometrial cancer patients, we sought to assess the safety, tolerability and toxicity profile of trastuzumab in patients with advanced/recurrent uterine serous carcinoma (USC) that overexpress HER2/neu in our multicenter randomized phase II trial.

METHODS

Patients were randomized 1:1 to receive carboplatin/paclitaxel (C/P) for 6 cycles ± trastuzumab (T) with the experimental arm continuing to receive single agent trastuzumab maintenance treatment until disease progression/toxicity. Progression-free-survival was the primary endpoint; overall-survival and toxicity were secondary endpoints. Adverse events (AEs) were compared between treatment arms.

RESULTS

There were 28 patients in the C/P arm and 32 patients in the experimental (C/P + T) arm. Fifty-eight patients (97%) experienced 977 treatment-related AEs of which 875 (89.6%) were low-grade (grade 1-2) and 102 (10.4%) were high-grade (grade 3-5). The mean ± standard deviation of AEs per patient was 15.5 ± 16.3 in the C/P arm and 17.0 ± 16.0 in the C/P + T arm. Gastrointestinal AEs were the most common in both arms (n = 155, 15.7%) of which 94.2% were low-grade (n = 146). Importantly, no significant difference between treatment arms was detected in any system-organ class of AE including cardiac AE. Five (17%) of 29 patients who received prolonged trastuzumab maintenance therapy had no sign of cumulative toxicity after an average (range) of 5.1 (4.2-6.3) years.

CONCLUSIONS

Trastuzumab appears to be safe and has a manageable toxicity profile both when used in combination with chemotherapy and when used for single agent maintenance in patients with HER2/neu positive USC. This safety profile is reassuring given the proven efficacy of trastuzumab in advanced/recurrent HER2/neu positive USC.

An update of the molecular mechanisms underlying doxorubicin plus trastuzumab induced cardiotoxicity

Cardiotoxicity is a major side effect of the chemotherapeutic drug doxorubicin (Dox), which is further exacerbated when it is combined with trastuzumab, a standard care approach for Human Epidermal growth factor Receptor-type 2 (HER2) positive cancer patients. However, the molecular mechanisms of the underlying cardiotoxicity of this combination are still mostly elusive. Increased oxidative stress, impaired energetic substrate uses and topoisomerase IIB inhibition are among the biological processes proposed to explain Dox-induced cardiomyocyte dysfunction. Since cardiomyocytes express HER2, trastuzumab can also damage these cells by interfering with neuroregulin-1 signaling and mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K)/Akt and focal adhesion kinase (FAK)-dependent pathways. Nevertheless, Dox and trastuzumab target other cardiac cell types, such as endothelial cells, fibroblasts, cardiac progenitor cells and leukocytes, which can contribute to the clinical cardiotoxicity observed. This review aims to summarize the current knowledge on the cardiac signaling pathways modulated by these two antineoplastic drugs highly used in the management of breast cancer, not only focusing on cardiomyocytes but also to broaden the knowledge of the potential impact on other cells found in the heart.

Intermittent left bundle branch block and acute heart failure in trastuzumab-induced cardiotoxicity

A 70-year-old woman with HER2+/ER+ breast cancer on adjuvant trastuzumab therapy without a history of cardiovascular disease presented with respiratory failure from influenza and was found to have intermittent left bundle branch block (LBBB) with new onset systolic heart failure. Her course was complicated by polymorphic ventricular tachycardia and recurrent chest pain. Significant investigations included a normal cardiac MRI and cardiac catheterisation with unobstructed coronaries. It was determined that the aetiology of her heart failure was trastuzumab-induced cardiotoxicity after comprehensive workup. This case highlights an uncommon presentation of LBBB and the steps taken to diagnose a rare cardiomyopathy.

Nano-Encapsulation of Coenzyme Q10 in Secondary and Tertiary Nano-Emulsions for Enhanced Cardioprotection and Hepatoprotection in Human Cardiomyocytes and Hepatocytes During Exposure to Anthracyclines and Trastuzumab

Introduction

CoenzymeQ₁₀ (CoQ₁₀) is a well-known antioxidant and anti-inflammatory agent with cardioprotective properties. However, clinical trials based on its oral administration have failed to provide significant effect on cardiac functionality. The main limitation of CoQ₁₀ is based on its very low oral bioavailability and instability that limit dramatically its effects as a cardioprotective agent. Herein, we loaded CoQ₁₀ in high bioavailable nano-emulsions (NEs) coated with chitosan or chitosan and hyaluronic acid in order to improve its performance.

Methods

We tested cardioprotective and hepatoprotective effects of CoQ₁₀-loaded nano-carriers against Doxorubicin and Trastuzumab toxicities in cardiomyocytes and liver cells through analysis of cell viability, lipid peroxidation, expression of leukotrienes, p65/NF-kB and pro-inflammatory cytokines involved in anticancer-induced cardio and hepatotoxicity.

Results

Nano-carriers showed high stability and loading ability and increased cell viability both in hepatocytes and cardiomyocytes during anticancer treatments. We observed that these effects are mediated by the inhibition of lipid peroxidation and reduction of the inflammation. CoQ₁₀-loaded nano-emulsions showed also strong anti-inflammatory effects reducing leukotriene B4 and p65/NF-κB expression and Interleukin 1β and 6 production during anticancer treatments.

Discussion

Anthracyclines and Human epidermal growth factor receptor (HER2) inhibitors have shown significant anticancer effects in clinical practice but their use is characterized by cardiotoxicity and hepatotoxicity. Nano-carriers loaded with CoQ₁₀ showed cardio and hepatoprotective properties mediated by reduction of oxidative damages and pro-inflammatory mediators. These results set the stage for preclinical studies of cardio and hepatoprotection in HER2+ breast cancer-bearing mice treated with Doxorubicin and Trastuzumab.

Cardiovascular Disease among Breast Cancer Survivors

Background

Among breast cancer survivors age > 50 years, deaths due to cardiovascular disease account for 35% of non-cancer related deaths. The increases in cardiovascular disease among breast cancer survivors is due to the cardiotoxic effects of breast cancer treatment and to overlapping risk factors for breast cancer and cardiovascular disease.

Methods

We conducted a study of a sample of 164 breast cancer patients in order to examine the frequency of cardiovascular disease. The overall objective was to examine the frequency of high blood pressure, myocardial infarction, cardiomyopathy, congestive heart failure, stroke, and venous thrombosis/thromboembolism among women who have been diagnosed with stage I-IV breast cancer and who had completed primary therapy for the disease. Data were collected by postal survey and abstraction of electronic medical records.

Results

A high percentage of the women (62.8%) had a reported history of high blood pressure. Fifty percent of the women had a reported history of high cholesterol. About 8.3% of the women were current smokers and 36.0% were former smokers. About 23.8% of the women had a reported history of diabetes. About 4.9% of the women had a reported history of congestive heart failure and 6.1% had a history of stroke.

Discussion

Additional studies are needed of cardiovascular risk factors and adverse cardiovascular events among breast cancer survivors. Of particular concern is whether patients with hypertension, hypercholesterolemia, and diabetes are receiving appropriate therapy to reduce their cardiovascular risk and prevent morbidity and mortality from adverse cardiovascular events.

Early morphological changes in cardiac mitochondria after subcutaneous administration of trastuzumab in rabbits: possible prevention with oral selenium supplementation

Trastuzumab-mediated cardiotoxicity poses a significant challenge in the treatment of human epidermal growth factor receptor 2-positive breast cancer. To understand the underlying mechanisms, we conducted experiments to determine ultrastructural changes of rabbit cardiac tissue under different experimental conditions, including differing doses of trastuzumab and supplementation with oral sodium selenite, an antioxidant. Histopathology revealed lymphocyte and macrophage infiltration in myocardium of rabbits receiving four doses of trastuzumab. Transmission electron microscopy showed substantial changes with trastuzumab, including edema with separation of myofibril bundles and rupture of sarcomeres. Within mitochondria, edema resulted in disorganization of the cristae. Some mitochondria exhibited eccentric projections of their membranes with disruption of both inner and outer membranes. These changes were seen to a lesser extent in rabbits who received oral sodium selenite prior to trastuzumab. Selenium is integral to functioning of mitochondrial glutathione peroxidases, important antioxidants that also maintain membrane integrity. If mitochondria are disrupted as part of trastuzumab cardiac toxicity, selenium supplementation might be an important therapeutic or preventive consideration. Larger studies to explore this hypothesis are warranted.

Curing breast cancer and killing the heart: A novel model to explain elevated cardiovascular disease and mortality risk among women with early stage breast cancer

Due to advances in prevention, early detection and treatment, early breast cancer mortality has decreased by nearly 40% during the last four decades. Yet, the risk of cardiovascular disease (CVD) mortality is significantly elevated following a breast cancer diagnosis, and it is a leading cause of death in this population. This review will discuss the most recent evidence for risks, pathology, mechanisms, and prevention of CVD morbidity and mortality in women with breast cancer. This evidence will be synthesized into a new model 'the compounding risk and protection model.' This model proposes that the balance between risk factors (i.e., older age, pre-existing traditional CVD risk factors and shared biologic pathways for CVD and cancer such as inflammation, as well as treatment-related and lifestyle toxicity) and potential protection factors (i.e., lifelong non-smoking, regular physical activity, a healthy diet rich in fruits and vegetables, and management of body weight and stress, heart failure therapy) determine the individual risk of CVD morbidity and mortality after diagnosis of early breast cancer.

Chemotherapeutic agents for the treatment of metastatic breast cancer: An update

Breast cancer is the second greatest cause of death among women worldwide; it comprises a group of heterogeneous diseases that evolves due to uncontrolled cellular growth and differentiation and the loss of normal programmed cell death. There are different molecular sub-types of breast cancer; therefore, various options are selected for treatment of different forms of metastatic breast cancer. However, the use of chemotherapeutic drugs is usually accompanied by deleterious side effects and the development of drug resistance when applied for a longer period. This review offers a classification of these chemotherapeutic agents according to their modes of action and therefore improves the understanding of molecular targets that are affected during treatment. Overall, it will allow the clinician to identify more specific targets to increase the effectiveness of a drug and to reduce general toxicity, resistance and other side effects.

Diagnosis, Treatment, and Prevention of Cardiovascular Toxicity Related to Anti-Cancer Treatment in Clinical Practice: An Opinion Paper from the Working Group on Cardio-Oncology of the Korean Society of Echocardiography

Cardiovascular (CV) toxicity associated with anti-cancer treatment is commonly encountered and raises critical problems that often result in serious morbidity or mortality. Most cardiac toxicities are related to the cumulative dose of chemotherapy; however, the type of chemotherapy, concomitant agents, and/or conventional CV risk factors have been frequently implicated in CV toxicity. Approximately half of the patients exhibiting CV toxicity receive an anthracycline-based regimen. Therefore, serologic biomarkers or cardiac imagings are important during anti-cancer treatment for early detection and the decision of appropriate management of cardiotoxicity. However, given the difficulty in determining a causal relationship, a multidisciplinary collaborative approach between cardiologists and oncologists is required. In this review, we summarize the CV toxicity and focus on the role of cardiac imaging in management strategies for cardiotoxicity associated with anti-cancer treatment.