Anthracycline-induced cardiomyopathy

Anthracycline-Induced Cardiomyopathy in Cancer Survivors: Management and Long-Term Implications

Recent advancements in personalized treatments, such as anthracycline chemotherapy, coupled with timely diagnoses, have contributed to a decrease in cancer-specific mortality rates and an improvement in cancer prognosis. Anthracyclines, a potent class of antibiotics, are extensively used as anticancer medications to treat a broad spectrum of tumors. Despite these advancements, a considerable number of cancer survivors face increased risks of treatment complications, particularly the cardiotoxic effects of chemotherapeutic drugs like anthracyclines. These effects can range from subclinical manifestations to severe consequences such as irreversible heart failure and death, highlighting the need for effective management of chemotherapy side effects for improved cancer care outcomes. Given the lack of specific treatments, early detection of subclinical cardiac events post-anthracycline therapy and the implementation of preventive strategies are vital. An interdisciplinary approach involving cardiovascular teams is crucial for the prevention and efficient management of anthracycline-induced cardiotoxicity. Various factors, such as age, gender, duration of treatment, and comorbidities, should be considered significant risk factors for developing chemotherapy-related cardiotoxicity. Tools such as electrocardiography, echocardiography, nuclear imaging, magnetic resonance imaging, histopathologic evaluations, and serum biomarkers should be appropriately used for the early detection of anthracycline-related cardiotoxicity. Furthermore, understanding the underlying biological mechanisms is key to developing preventive measures and personalized treatment strategies to mitigate anthracycline-induced cardiotoxicity. Exploring specific cardiotoxic mechanisms and identifying genetic variations can offer fresh perspectives on innovative, personalized treatments. This chapter aims to discuss cardiomyopathy following anthracycline therapy, with a focus on molecular mechanisms, preventive strategies, and emerging treatments.

The inflammatory spectrum of cardiomyopathies

Infiltration of the myocardium with various cell types, cytokines and chemokines plays a crucial role in the pathogenesis of cardiomyopathies including inflammatory cardiomyopathies and myocarditis. A more comprehensive understanding of the precise immune mechanisms involved in acute and chronic myocarditis is essential to develop novel therapeutic approaches. This review offers a comprehensive overview of the current knowledge of the immune landscape in cardiomyopathies based on etiology. It identifies gaps in our knowledge about cardiac inflammation and emphasizes the need for new translational approaches to improve our understanding thus enabling development of novel early detection methods and more effective treatments.

Sildenafil for Primary Prevention of Anthracycline-Induced Cardiac Toxicity: A Phase I/II Randomized Clinical Trial, SILDAT-TAHA6 Trial

Background

Previous animal studies have shown a protective effect of 5-phosphodiesterase inhibitors on cancer therapeutics-related cardiac dysfunction (CTRCD) of anthracyclines.

Aim

The aim of this study was to evaluate the clinical effect of sildenafil on the primary prevention of CTRCD in human.

Materials and Methods

In this randomized double-blind clinical trial, the primary end point was efficacy in preventing the reduction of left ventricular ejection fraction (LVEF). The intervention group patients received sildenafil at a dose of 25 milligrams twice a day before starting the chemotherapeutic regimen, and the control group received placebo. All the patients at baseline and after the 6-month follow-up underwent 4D and speckle-tracking echocardiography and cardiac MRI, accompanied by hs-troponin I and NT-Pro-BNP measurement.

Results

Sixty patients were enrolled in this study, and data from 52 patients (24 patients in the intervention group and 28 patients in the control group) were used in the final analysis. Our findings showed that in the intervention and control groups, LVEF was dropped from 61.28 ± 7.36 to 51.57 ± 7.67 (difference (D) = −9.71 ± 11.95, p=0.003) and from 57.9 ± 7.29 to 50.2 ± 7.02% (D = −7.7 ± 5.93; p=0.001), respectively (between-group difference = −2.01%, p=0.26). CTRCD was detected in 11 patients in the control group (42.8%) and 10 in the intervention group (41.6%, p=0.51).

Conclusion

Consumption of sildenafil for primary prevention of anthracycline-induced cardiac toxicity seems to be unbeneficial. This trial is registered with IRCT20180506039554N1.

Diagnosis and Management of Myocarditis: An Evidence-Based Review for the Emergency Medicine Clinician

BACKGROUND

Myocarditis is a potentially fatal condition that can be misdiagnosed in the emergency department (ED) setting.

OBJECTIVE

The purpose of this narrative review article is to provide a summary of the background, pathophysiology, diagnosis, and management of myocarditis, with a focus on emergency clinicians.

DISCUSSION

Myocarditis occurs when inflammation of the heart musculature causes cardiac dysfunction. Symptoms may range from mild to severe and are often preceded by a viral prodrome. Laboratory assessment and an electrocardiogram can be helpful for the diagnosis, but echocardiography is the ideal test in the ED setting. Some patients may also require advanced imaging, though this will often occur during hospitalization or follow-up. Treatment is primarily focused on respiratory and hemodynamic support. Initial hemodynamic management includes vasopressors and inotropes, whereas more severe cases may require an intra-aortic balloon pump, extracorporeal membrane oxygenation, or a ventricular assist device. Nonsteroidal anti-inflammatory drugs should be avoided while intravenous immunoglobulin is controversial.

CONCLUSION

Myocarditis is a serious condition with the potential for significant morbidity and mortality. It is important for clinicians to be aware of the current evidence regarding the diagnosis, management, and disposition of these patients.

The role of iron in doxorubicin-induced cardiotoxicity: recent advances and implication for drug delivery

As an anthracycline antibiotic, doxorubicin (DOX) is one of the most potent and widely used chemotherapeutic agents for treating various types of tumors. Unfortunately, the clinical application of this drug results in severe side effects, particularly dose-dependent cardiotoxicity. There are multiple mechanisms involved with the cardiotoxicity caused by DOX, among which intracellular iron homeostasis plays an essential role based on a recent discovery. In this mini-review, we summarize the clinical features and symptoms of DOX-dependent cardiotoxicity, discuss the correlation between iron and cardiotoxicity, and highlight the involvement of iron-dependent ferroptotic cell death therein. Recent advances in this topic will aid the development of novel DOX delivery systems with reduced adverse effects, and expand the clinical application of anthracycline.

Myocarditis in Paediatric Patients: Unveiling the Progression to Dilated Cardiomyopathy and Heart Failure

Myocarditis is a challenging and potentially life-threatening disease associated with high morbidity in some paediatric patients, due to its ability to present as an acute and fulminant disease and to ultimately progress to dilated cardiomyopathy. It has been described as an inflammatory disease of the myocardium caused by diverse aetiologies. Viral infection is the most frequent cause of myocarditis in developed countries, but bacterial and protozoal infections or drug hypersensitivity may also be causative agents. The prompt diagnosis in paediatric patients is difficult, as the spectrum of clinical manifestation can range from no myocardial dysfunction to sudden cardiac death. Recent studies on myocarditis pathogenesis have revealed a triphasic nature of this disease, which influences the diagnostic and therapeutic strategies to adopt in each patient. Endomyocardial biopsy remains the gold standard for diagnosing myocarditis, and several non-invasive diagnostic tools can be used to support the diagnosis. Intravenous immunoglobulin has become part of routine practice in the treatment of myocarditis in paediatric patients at many centres, but its true effect on the cardiac function has been the target of many studies. The aim of this review is to approach the recently discovered facets of paediatric myocarditis regarding its progression to dilated cardiomyopathy.

Cardiotoxicity of anthracycline therapy: current perspectives

Anthracyclines, especially doxorubicin and daunorubicin, are the drugs of first choice in the treatment of patients with hematologic malignancies, soft-tissue sarcomas, and solid tumors. Unfortunately, the use of anthracyclines is limited by their dose-dependent and cumulative cardiotoxicity. The molecular mechanism responsible for anthracycline-induced cardiotoxicity remains poorly understood, although experimental and clinical studies have shown that oxidative stress plays the main role. Hence, antioxidant agents, especially dexrazoxane, and also other drug classes (statins, β-blockers) proved to have a beneficial effect in protecting against anthracycline-induced cardiotoxicity. According to previous clinical trials, the major high-risk factors for anthracycline-induced cardiotoxicity are age, body weight, female gender, radiotherapy, and other diseases such as Down syndrome, familial dilated cardiomyopathy, diabetes and hypertension. Consequently, further studies are needed to elucidate the molecular pathogenesis of anthracycline-induced cardiotoxicity and also to discover new cardioprotective agents against anthracycline-induced cardiotoxicity.

Anthracycline treatment and ventricular remodeling in left ventricular assist device patients

Nonischemic cardiomyopathy can complicate antineoplastic therapy and lead to irreversible heart failure. We evaluated structural changes at the time of left ventricular assist device implantation in heart failure patients who had been exposed to anthracycline, and we correlated those changes with clinical presentation. We retrospectively studied left ventricular core samples taken at implantation of the HeartMate II left ventricular assist device in 12 heart failure patients (mean age, 46 ± 16 yr) who had histories of anthracycline exposure. We evaluated those samples for hypertrophy, myocytolysis, and fibrosis. Histopathologic findings showed moderate-to-severe myocyte hypertrophy, moderate myocytolysis, and perivascular and interstitial fibrosis with areas of replacement fibrosis. Ultrastructural studies revealed marked decreases in myofibrils, diffuse mitochondrial swelling, and disorganization of the sarcoplasmic reticulum. The interval between anthracycline therapy and heart failure was a mean of 6.8 ± 5.7 years; duration of heart failure symptoms, 38 ± 47 months; and duration of device support, 414 ± 266 days. Four patients are continuing on device support, 3 have undergone transplantation, 3 have undergone device explantation, and 2 have died. The time of heart failure onset and the duration of symptoms did not correlate with the severity and extent of the histopathologic changes. The histopathologic findings and the clinical course varied in heart failure patients with anthracycline exposure. No correlation was observed between anthracycline therapy and the development or duration of heart failure symptoms, severity of histopathologic changes, or outcomes.

Capecitabine-induced cardiotoxicity: more evidence or clinical approaches to protect the patients' heart?

Fluoropyrimidines, such as capecitabine and 5-fluorouracil, may cause cardiac toxicity. In recent years, the incidence of this side effect has increased and it is expected to further rise due to the population aging and the disproportionate incidence of breast and gastrointestinal cancers in older individuals. The spectrum of cardiac manifestations includes different signs and symptoms and the diagnosis may be difficult. Here, we report the case of a 43-year-old woman with advanced breast cancer who was rechallenged with a capecitabine-based regimen after experiencing a cardiac adverse event during the first fluoropyrimidine exposure. This real-practice case serves as a springboard for discussion about the current evidence on differential diagnosis of capecitabine-related cardiac toxicity, its risk factors, and the underpinning mechanisms of early onset. Moreover, we discussed whether a rechallenge with fluoropyrimidines could be safe in patients who had experienced a previous cardiac adverse event.

Epirubicin permeation of personal protective equipment can induce apoptosis in keratinocytes

The present study investigated the epirubicin (EPI) permeability of various commercially available glove types, as well as toxicity mechanisms and effects on human keratinocyte cell line (HaCaT). Permeability experiments were carried out on various commercially available gloves, differing as regards material and thickness. Permeability was evaluated after different "contact times" and the influence of EPI solution's pH (acid and neutral) on permeability was also examined. Toxicity of EPI toward skin was tested by evaluating the effects of the drug on cell growth and apoptosis, by using an in vitro model based on cultured immortalized human keratinocytes. No permeation was detected in the case of EPI neutral solutions; in contrast, acid solutions were found to penetrate low thickness nitrile gloves. Obtained results also showed the induction of apoptosis in epithelial cells through the activation of intrinsic pathway p53-independent occurring even when cells are exposed at low drug concentration. EPI solution's pH influences the glove's permeability; once penetrated, EPI at concentrations lower than those able to penetrate the nitrile glove during the 8-h work-shift can cause apoptosis in epithelial cells. The findings reported here highly support the choice of either natural rubbers gloves or high thickness nitrile ones for preventing the occupational exposure to EPI.

Berberine attenuates doxorubicin-induced cardiotoxicity in mice

This study investigated the effects of berberine, a natural alkaloid, on doxorubicin-induced cardiotoxicity in mice. Mice were injected intraperitoneally with saline 10 ml/kg (n = 10), doxorubicin 2.5 mg/kg (n = 10), 60 mg/kg berberine 1 h before doxorubicin 2.5 mg/kg (n = 10), or 60 mg/kg berberine alone (n = 10) every other day for 14 days. Body weight, general condition and mortality were recorded over the 14-day study period. Electro cardiography was performed before the start of treatment and after 14 days and plasma lactate dehydrogenase (LDH) activity was measured after 14 days. At the end of the study period the heart was excised and examined histologically. An increase in mortality, an initial decrease in body weight, increased LDH activity, prolongation of QRS duration and increased myocardial injury were seen in the doxorubicin-treated group compared with the saline control group. These changes were significantly attenuated by pretreatment with berberine. The study suggests that berberine may have a potential protective role against doxorubicin-induced cardiotoxicity in mice.

Doxorubicin can penetrate nitrile gloves and induces apoptosis in keratinocytes cell lines

Doxorubicin (DOXO) is an anthracycline antibiotic which is used in the treatment of human malignancies such as leukemia, lymphoma and a number of solid tumors, particularly breast cancer. Anthracyclines have been reported to contaminate chemotherapy workstation surfaces as well as other workplaces surfaces. The occupational exposure to these drugs could occur in hospitals, for nurses involved in anthracyclines preparation and administration, in chemical industries during the commercial formulate syntheses, and in analytical laboratories. Numerous studies investigated cutaneous effects related to DOXO administration, on the contrary few literature data are available about effects on the skin due to the direct contact with the drug. The present study investigated the DOXO permeability of three commercially available gloves' types used to protect skin in occupational contexts, as well as the effects of DOXO on human keratinocyte cell line (HaCaT). The results suggest that the DOXO permeability of gloves depends not only on glove material but also on DOXO solutions' pH, in fact nitrile gloves can be penetrated by acid solutions, while neither natural rubbers nor nitrile gloves are permeable to neutral solutions. Moreover, DOXO solutions, even at low concentration, cause apoptosis in epithelial cells, through activation of intrinsic pathway p53-independent.

Myocarditis

Myocarditis is an uncommon, potentially life-threatening disease that presents with a wide range of symptoms in children and adults. Viral infection is the most common cause of myocarditis in developed countries, but other etiologies include bacterial and protozoal infections, toxins, drug reactions, autoimmune diseases, giant cell myocarditis, and sarcoidosis. Acute injury leads to myocyte damage, which in turn activates the innate and humeral immune system, leading to severe inflammation. In most patients, the immune reaction is eventually down-regulated and the myocardium recovers. In select cases, however, persistent myocardial inflammation leads to ongoing myocyte damage and relentless symptomatic heart failure or even death. The diagnosis is usually made based on clinical presentation and noninvasive imaging findings. Most patients respond well to standard heart failure therapy, although in severe cases, mechanical circulatory support or heart transplantation is indicated. Prognosis in acute myocarditis is generally good except in patients with giant cell myocarditis. Persistent, chronic myocarditis usually has a progressive course but may respond to immunosuppression.

Improving the therapeutic index of anthracycline chemotherapy: focus on liposomal doxorubicin (Myocet)

Anthracyclines are valuable cytotoxic agents in cancer treatment. However, their usefulness is limited by cumulative dose-dependent cardiotoxicity that may manifest as life-threatening congestive heart failure. To avoid cardiotoxicity, the use of doxorubicin is typically capped at a safe cumulative dose. Liposomal formulations may reduce cardiac risks whilst maintaining anti-cancer efficacy. Efficacy and safety studies of non-pegylated liposomal doxorubicin (NPLD) in metastatic breast cancer (MBC) are reviewed, along with studies that examine efficacy and cardiac tolerability in combination with newer agents such as paclitaxel and trastuzumab. These show that cardiac safety of liposomal doxorubicin is similar to that of epirubicin in cumulative dose, but that the formulation, unlike epirubicin, has similar anti-cancer efficacy to doxorubicin at equimolar doses. Liposomal doxorubicin may have a better therapeutic index than non-liposomal anthracyclines. This justifies further studies in patients where cumulative cardiotoxicity is a concern, as does study of its use with other potentially cardiotoxic agents.