Detection of anthracycline-induced cardiotoxicity

Investigation of the effect of intravitreal bevacizumab treatment on left heart function using speckle tracking echocardiography

INTRODUCTION AND OBJECTIVES

Vascular endothelial growth factor (VEGF) inhibitors are widely used in oncology and ophthalmology. Although these agents have been shown to increase the risk of cardiovascular events in systemic use, the effect of local applications is unclear. In our study, we aimed to investigate the effects of anti-VEGF agents on left heart functions after intravitreal injection using speckle tracking echocardiography.

METHODS

In this prospectively designed study, 44 patients who were going to start intravitreal anti-VEGF treatment were included in the study. Patients were evaluated with speckle tracking echocardiography before the first anti-VEGF administration and at three months of anti-VEGF treatment.

RESULTS

Global longitudinal strain (GLS) values at three months were lower in the patients who participated in the study and this was statistically significant (-18.77±2.17, -18.60±2.01, p=0.001). Also, there was a statistically significant decrease in the mean values of GLS (GLS4CH) obtained from apical four space image, GLS (GLSAPLAX) obtained from apical long axis image and GLS (GLS2CH) obtained from apical 2 space image at month 0 and month 3 (-19.08±2.39, -18.93±2.26, p=0.004; -18.81±2.29, -18.60±2.12, p=0.001; -18.44±2.31, -18.27±2.12, p=0.013, respectively).

CONCLUSION

The slight decrease in GLS in our study suggests that the use of intravitreal anti-VEGF agents may have cardiac effects.

Potential of exosomes as diagnostic biomarkers and therapeutic carriers for doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is a kind of representative anthracyclines. It has greatly prolonged lifespan of cancer patients. However, a long course of DOX chemotherapy could induce various forms of deaths of cardiomyocytes, such as apoptosis, pyroptosis and ferroptosis, contributing to varieties of cardiac complications called cardiotoxicity. It has become a major concern considering the large number of cancer patients' worldwide and increased survival rates after chemotherapy. Exosomes, a subgroup of extracellular vesicles (EVs), are secreted by nearly all cells and consist of lipid bilayers, nucleic acids and proteins. They can serve as mediators between intercellular communication via the transfer of bioactive molecules from secretory to recipient cells, modulating multiple pathophysiological processes. It has been proven that exosomes in body fluids can serve as biomarkers for doxorubicin-induced cardiotoxicity (DIC). Moreover, exosomes have attracted considerable attention because of their capacity as carriers of certain proteins, genetic materials (miRNA and lncRNA), and chemotherapeutic drugs to decrease the dosage of DOX and alleviate cardiotoxicity. This review briefly describes the characteristics of exosomes and highlights their clinical application potential as diagnostic biomarkers and drug delivery vehicles for DIC, thus providing a strategy for addressing it based on exosomes.

Speckle-Tracking Echocardiography for Cardioncological Evaluation in Bevacizumab-Treated Colorectal Cancer Patients

Angiogenesis inhibitor Bevacizumab (BVZ) may lead to the development of adverse effects, including hypertension and cardiac ischemia. Whether assessment of changes in myocardial strain by two-dimensional speckle-tracking echocardiography (2D-STE) can be of value in detecting BVZ-mediated cardiotoxicity at an earlier stage is not known. We investigated whether 2D-STE can non-invasively detect early evidence of cardiotoxicity in metastatic colorectal cancer (mCRC) patients treated with BVZ. Between January and June 2019, 25 consecutive patients (71.8 ± 7.5 year/old, 17 males) with mCRC were prospectively enrolled. Patients underwent physical examination, blood tests, and conventional 2D-transthoracic echocardiography implemented with 2D-STE analysis, at baseline and at 3 and 6 months following treatment with BVZ (15 mg/kg every 15 days) + 5-fluorouracil/folinic acid plus oxaliplatin (FOLFOX i.v.). At 6-month follow-up, we assessed occurrence of global longitudinal strain (GLS) impairment (> 15% decrease in GLS compared with baseline) as primary end-point and a new-onset systemic hypertension (secondary end-point). On average, GLS showed a progressive significant impairment after BVZ, from - 17.4 ± 3.2% at baseline to - 16 ± 2.9% (p = 0.003) at 6-month follow-up; > 15% decrease in GLS (primary end-point) was detected in 9 patients (36%). All other strain parameters remained unchanged. New-onset systemic hypertension (secondary end-point) was diagnosed in five patients (20%). No significant changes were observed in serial high-sensitivity cardiac troponin I measurements. No patient developed significant changes in LV size or LV ejection fraction; no case of clinically symptomatic HF was observed during BVZ-treatment. Measurement of GLS by 2D-STE analysis can effectively detect BVZ-mediated cardiotoxicity at an early stage.

Cardiac Damage in Anthracyclines Therapy: Focus on Oxidative Stress and Inflammation

Significance: Despite their serious side effects, anthracyclines (ANTs) are the most prescribed chemotherapeutic drugs because of their strong efficacy in both solid and hematological tumors. A major limitation to ANTs clinical application is the severe cardiotoxicity observed both acutely and chronically. The mechanism underlying cardiac dysfunction under chemotherapy is mainly dependent on the generation of oxidative stress and systemic inflammation, both of which lead to progressive cardiomyopathy and heart failure. Recent Advances: Over the years, the iatrogenic ANTs-induced cardiotoxicity was believed to be simply given by iron metabolism and reactive oxygen species production; however, several experimental data indicate that ANTs may use alternative damaging mechanisms, such as topoisomerase 2β inhibition, inflammation, pyroptosis, immunometabolism, and autophagy. Critical Issues: In this review, we aimed at discussing ANTs-induced cardiac injury from different points of view, updating and focusing on oxidative stress and inflammation, since these pathways are not exclusive or independent from each other but they together importantly contribute to the complexity of ANTs-induced multifactorial cardiotoxicity. Future Directions: A deeper understanding of the mechanistic signaling leading to ANTs side effects could reveal crucial targeting molecules, thus representing strategic knowledge to promote better therapeutic efficacy and lower cardiotoxicity during clinical application.

Echocardiographic Assessment for the Detection of Cardiotoxicity Due to Vascular Endothelial Growth Factor Inhibitor Therapy in Metastatic Renal Cell and Colorectal Cancers

BACKGROUND

Cardio-oncology is a recently established discipline that focuses on the management of patients with cancer who are at risk for developing cardiovascular complications as a result of their underlying oncologic treatment. In metastatic colorectal cancer (mCRC) and metastatic renal cell carcinoma (mRCC), vascular endothelial growth factor inhibitor (VEGF-i) therapy is commonly used to improve overall survival. Although these novel anticancer drugs may lead to the development of cardiotoxicity, whether early detection of cardiac dysfunction using serial echocardiography could potentially prevent the development of heart failure in this patient population requires further study. The aim of this study was to investigate the role of two-dimensional speckle-tracking echocardiography in the detection of cardiotoxicity due to VEGF-i therapy in patients with mCRC or mRCC.

METHODS

Patients with mRCC or mCRC were evaluated using serial echocardiography at baseline and 1, 3, and 6 months following VEGF-i treatment.

RESULTS

A total of 40 patients (34 men; mean age, 63 ± 9 years) receiving VEGF-i therapy were prospectively recruited at two academic centers: 26 (65%) were receiving sunitinib, eight (20%) pazopanib, and six (15%) bevacizumab. The following observations were made: (1) 8% of patients developed clinically asymptomatic cancer therapeutics-related cardiac dysfunction; (2) 30% of patients developed clinically significant decreases in global longitudinal strain, a marker for early subclinical cardiac dysfunction; (3) baseline abnormalities in global longitudinal strain may identify a subset of patients at higher risk for developing cancer therapeutics-related cardiac dysfunction; and (4) new or worsening hypertension was the most common adverse cardiovascular event, afflicting nearly one third of the study population.

CONCLUSIONS

Cardiac dysfunction defined by serial changes in myocardial strain assessed using two-dimensional speckle-tracking echocardiography occurs in patients undergoing treatment with VEGF-i for mCRC or mRCC, which may provide an opportunity for preventive interventions.

Electrochemical, spectroscopic and theoretical monitoring of anthracyclines' interactions with DNA and ascorbic acid by adopting two routes: Cancer cell line studies

Pharmacodynamic interactions of three anthracycline antibiotics namely doxorubicin (DXH), epirubicin (EpiDXH) and daunorubicin (DNR) with DNA in the absence and presence of ascorbic acid (AA) as natural additive were monitored under physiological conditions (pH = 7.4, 4.7 and T = 309.5K). Route–1 (Anthracycline–AA–DNA) and Route–2 (Anthracycline–DNA–AA) were adopted to see the interactional behavior by cyclic voltammetry (CV) and UV-visible spectroscopy. In comparison to Route–2; voltammetric and spectral responses as well as binding constant (K_b) and Gibb’s free energy change (ΔG) values revealed strongest and more favorable interaction of anthracycline–AA complex with DNA via Route–1. K_b, s (binding site sizes) and ΔG evaluated from experimental (CV, UV-Vis) and theoretical (molecular docking) findings showed enhanced binding strength of tertiary complexes as compared to binary drug–DNA complexes. The results were found comparatively better at pH 7.4. Consistency was observed in binding parameters evaluated from experimental and theoretical techniques. Diffusion coefficients (D_o) and heterogeneous electron transfer rate constant (k_s,h) confirmed the formation of complexes via slow diffusion kinetics. Percent cell inhibition (%C_inh) of anthracyclines for non-small cell cancer cell lines (NSCCLs) H-1299 and H-157 were evaluated higher in the presence of AA which further complimented experimental and theoretical results.

Untying the knot: protein quality control in inherited cardiomyopathies

Mutations in genes encoding sarcomeric proteins are the most important causes of inherited cardiomyopathies, which are a major cause of mortality and morbidity worldwide. Although genetic screening procedures for early disease detection have been improved significantly, treatment to prevent or delay mutation-induced cardiac disease onset is lacking. Recent findings indicate that loss of protein quality control (PQC) is a central factor in the disease pathology leading to derailment of cellular protein homeostasis. Loss of PQC includes impairment of heat shock proteins, the ubiquitin-proteasome system, and autophagy. This may result in accumulation of misfolded and aggregation-prone mutant proteins, loss of sarcomeric and cytoskeletal proteins, and, ultimately, loss of cardiac function. PQC derailment can be a direct effect of the mutation-induced activation, a compensatory mechanism due to mutation-induced cellular dysfunction or a consequence of the simultaneous occurrence of the mutation and a secondary hit. In this review, we discuss recent mechanistic findings on the role of proteostasis derailment in inherited cardiomyopathies, with special focus on sarcomeric gene mutations and possible therapeutic applications.

Embryonic stem cell-derived cardiomyocytes for the treatment of doxorubicin-induced cardiomyopathy

BACKGROUND

Doxorubicin (Dox) is a chemotherapy drug with limited application due to cardiotoxicity that may progress to heart failure. This study aims to evaluate the role of cardiomyocytes derived from mouse embryonic stem cells (CM-mESCs) in the treatment of Dox-induced cardiomyopathy (DIC) in mice.

METHODS

The mouse embryonic stem cell (mESC) line E14TG2A was characterized by karyotype analysis, gene expression using RT-PCR and immunofluorescence. Cells were transduced with luciferase 2 and submitted to cardiac differentiation. Total conditioned medium (TCM) from the CM-mESCs was collected for proteomic analysis. To establish DIC in CD1 mice, Dox (7.5 mg/kg) was administered once a week for 3 weeks, resulting in a cumulative Dox dose of 22.5 mg/kg. At the fourth week, a group of animals was injected intramyocardially with CM-mESCs (8 × 105 cells). Cells were tracked by a bioluminescence assay, and the body weight, echocardiogram, electrocardiogram and number of apoptotic cardiomyocytes were evaluated.

RESULTS

mESCs exhibited a normal karyotype and expressed pluripotent markers. Proteomic analysis of TCM showed proteins related to the negative regulation of cell death. CM-mESCs presented ventricular action potential characteristics. Mice that received Dox developed heart failure and showed significant differences in body weight, ejection fraction (EF), end-systolic volume (ESV), stroke volume (SV), heart rate and QT and corrected QT (QTc) intervals when compared to the control group. After cell or placebo injection, the Dox + CM-mESC group showed significant increases in EF and SV when compared to the Dox + placebo group. Reduction in ESV and QT and QTc intervals in Dox + CM-mESC-treated mice was observed at 5 or 30 days after cell treatment. Cells were detected up to 11 days after injection. The Dox + CM-mESC group showed a significant reduction in the percentage of apoptotic cardiomyocytes in the hearts of mice when compared to the Dox + placebo group.

CONCLUSIONS

CM-mESC transplantation improves cardiac function in mice with DIC.

Independent replication of polymorphisms predicting toxicity in breast cancer patients randomized between dose-dense and docetaxel-containing adjuvant chemotherapy

Introduction

Although pharmacogenomics has evolved substantially, a predictive test for chemotherapy toxicity is still lacking. We compared the toxicity of adjuvant dose-dense doxorubicin-cyclophosphamide (ddAC) and docetaxel-doxorubicin-cyclophosphamide (TAC) in a randomized multicenter phase III trial and replicated previously reported associations between genotypes and toxicity.

Results

646 patients (97%) were evaluable for toxicity (grade 2 and higher). Whereas AN was more frequent after ddAC (P < 0.001), TAC treated patients more often had PNP (P < 0.001). We could replicate 2 previously reported associations: TECTA (rs1829; OR 4.18, 95% CI 1.84-9.51, P = 0.001) with PNP, and GSTP1 (rs1138272; OR 2.04, 95% CI 1.13-3.68, P = 0.018) with PNP.

Materials and methods

Patients with pT1-3, pN0-3 breast cancer were randomized between six cycles A60C600 every 2 weeks or T75A50C500 every 3 weeks. Associations of 13 previously reported single nucleotide polymorphisms (SNPs) with the most frequent toxicities: anemia (AN), febrile neutropenia (FN) and peripheral neuropathy (PNP) were analyzed using logistic regression models.

Conclusions

In this independent replication, we could replicate an association between 2 out of 13 SNPs and chemotherapy toxicities. These results warrant further validation in order to enable tailored treatment for breast cancer patients.

Electrophysiological effects of anthracyclines in adult survivors of pediatric malignancy

BACKGROUND

Anthracycline use is limited by cardiotoxicity, including arrhythmias and left ventricular (LV) dysfunction. We aim to characterize the association between electrophysiological changes and LV dysfunction.

METHODS

A retrospective chart review was conducted, including all 147 pediatric cancer survivors at our institution over 18 years of age and treated with an anthracycline. One hundred thirty-four patients who had at least one electrocardiogram (ECG) and echocardiogram were analyzed. The association between dysfunction and baseline characteristics, treatment history, and electrocardigraphic parameters were analyzed using multivariable logistic regression. Additionally, a longitudinal generalized estimating equation (GEE) model was used to examine the temporal association between repeated measure corrected QT (QTc) intervals and subsequent LV function.

RESULTS

In our population, 24% of patients had LV dysfunction. The initial posttreatment QTc interval was longer in patients with LV dysfunction (438 ± 35 vs. 420 ± 20 msec, P = 0.002). In logistic regression analysis, QTc interval (P < 0.001) and cumulative radiation dose (P = 0.027) were associated with LV dysfunction. On ECGs performed prior to evidence of LV dysfunction, the QTc was longer than on ECGs preceding a normal echocardiogram (451 ± 32 msec vs. 423 ± 25 msec, P < 0.001). Mean time from QTc ≥ 450 msec to evidence of LV dysfunction was 1.8 ± 2.9 years. In the longitudinal GEE model, QTc prolongation was associated with subsequent decreased fractional shortening.

CONCLUSIONS

Among adult survivors of pediatric cancer treated with anthracyclines, prolongation of the QTc interval was associated with subsequent LV dysfunction.

Cardioprotective Effects of a Phlorotannin Extract Against Doxorubicin-Induced Cardiotoxicity in a Rat Model

Long-term therapy with doxorubicin (DOX) is associated with high incidence of cumulative and irreversible dilated cardiomyopathy. The goal of this study was to evaluate the cardioprotective effects and safety of a phlorotannin extract from a brown algae Ecklonia cava (Seapolynol™, SPN) against DOX-induced cardiotoxicity in a rat model. A total of 42 rats were divided into six groups: control, low-dose SPN (LDS), high-dose SPN (HDS), DOX, DOX with low-dose SPN (DOX+LDS), and DOX with high-dose SPN (DOX+HDS). Echocardiography was performed at baseline and after 6 weeks. In left ventricular (LV) ejection fraction, DOX and DOX+LDS groups showed significant decreases (P < .001), while LDS, HDS, and DOX+HDS groups showed no significant change compared with control group. In LV mass index, DOX and DOX+LDS groups showed significant increases (P < .001 and P = .013), while LDS, HDS, and DOX+HDS groups showed no significant change compared with control group. In electron microscopy of the LV wall tissue, DOX+HDS group showed markedly less impaired myofibrils and mitochondria compared with both DOX and DOX+LDS groups. On the findings in echocardiography and electron microscopy, 6-week oral administration of SPN was safe and cardioprotective in a DOX-induced rat cardiotoxicity model in a dose-dependent manner.

Yield of screening echocardiograms during pediatric follow-up in survivors treated with anthracyclines and cardiotoxic radiation

BACKGROUND

Guidelines published by the Children's Oncology Group recommend screening echocardiograms for childhood cancer survivors exposed to anthracyclines and/or cardiotoxic radiation. This study aims to assess risk factors for cardiac late effects while evaluating the overall yield of screening echocardiograms.

PROCEDURE

Demographics, exposures, and echocardiogram results were abstracted from the medical records of survivors diagnosed at ≤ 21 years old and ≥ 2 years off therapy who were exposed to anthracyclines and/or potentially cardiotoxic radiotherapy. Descriptive statistics and logistic regressions were performed and the yield of screening echocardiograms was calculated.

RESULTS

Of 853 patients, 1,728 screening echocardiograms were performed, and 37 patients had an abnormal echocardiogram (overall yield 2.1%). Yields were only somewhat higher in more frequently screened patients. Risk factors for an abnormal result included anthracycline dose of ≥300 mg/m² (adjusted odds ratio [aOR] 3.1; 95% confidence interval [CI]: 1.3-7.2; P < 0.01) with a synergist relationship in patients who also received radiation doses ≥30 Gy (aOR 7.0; 95% CI: 1.6-31.9; P = 0.01), as well as autologous bone marrow transplant (OR 3.3; 95% CI: 1.3-8.5; P = 0.01). Sex, race, age at diagnosis, and cyclophosphamide exposure were not statistically significant risk factors, and no patient receiving <100 mg/m² anthracycline dose without concomitant radiation had an abnormal echocardiogram.

CONCLUSIONS

Dose-dependent and synergist anthracycline and cardiotoxic radiotherapy risks for developing cardiomyopathy were confirmed. However, previously identified risk factors including female sex, black race, and early age at diagnosis were not replicated in this cohort. The yields showed weak correlation across frequency categories. Echocardiographic screening recommendations for low-risk pediatric patients may warrant re-evaluation.

Monitoring of Anthracycline-Induced Cardiotoxicity

Objective:

To review the literature regarding the appropriate monitoring for anthracycline-induced cardiotoxicity.

Data Sources:

A MEDLINE search of the literature was performed (1966–August 2007). Search terms included anthracycline, cardiotoxicity, and monitoring. Additional references were identified through bibliographic reviews.

Data Synthesis:

Anthracycline medications are effective in the treatment of many malignancies but their use is limited by their associated cardiotoxicity. The focus of anthracycline-induced cardiotoxicity prevention has been on monitoring cardiac function during treatment; however, a consensus on the most appropriate way to monitor patients is not available. Most guidelines lack specific details on the appropriate methods of cardiac evaluation and schedule. One guideline that does provide specific recommendations on both the method of evaluation and schedule has been criticized for being too restrictive, costly, and tacking in evidentiary support. The literature is insufficient in evaluation of the predictive value of cardiac function monitoring by echocardiography or radionuclide angiography during anthracycline therapy and the future development of cardiotoxicity, the necessity of baseline cardiac function monitoring, the optimal follow-up cardiac evaluation schedule, and the addition of risk stratification to monitoring schemes.

Conclusions:

Although guidelines are Inadequate to predict and prevent anthracycline-induced cardiotoxicity, until further research is available, following one of the existing guidelines to monitor for this adverse effect is a practical solution.

The relationship between plasma hyaluronan levels and anthracycline-related cardiotoxicity in breast cancer patients

AIM

Anthracycline-derived antineoplastic agents are used as the main form of treatment in many malignant diseases, including breast cancer and childhood cancers. Cardiotoxicity is one of the most feared life-threatening complications of cancer therapy. In the present study, we aimed to investigate the relationship between plasma hyaluronan (HA) levels and anthracycline-induced cardiotoxicity.

MATERIALS AND METHODS

Fifty eight of 73 female patients who were diagnosed with breast cancer and treated with a chemotherapy regimen including anthracycline were enrolled in this study. Anamneses were taken from each patient before and after chemotherapy. Further, physical examinations, electrocardiography, and transthoracic echocardiography were performed, and plasma hyaluronan levels were determined by using ELISA assay for each patient before and after treatment.

RESULTS

Following anthracycline-based chemotherapy, the average left ventricular ejection fraction decreased (62.6±3.7% vs. 58.6±4.4%, p<0.001), and diastolic functions significantly deteriorated (p<0.001). However, troponin and hyaluronan levels significantly increased following chemotherapy [Troponin (ng/ml, mean±SD): before 0.01±0.002, after 0.037±0.02, p<0.001], [Plasma HA (ng/ml, mean±SD): before 41.3±5.4, after 70±8.5, p<0.001]. The increase in troponin values correlated with systolic dysfunction (p=0.002), but did not correlate with diastolic dysfunction (p=0.661). Significant correlations were found between systolic/diastolic dysfunction and plasma HA levels (r=0.417, p=0.001; r=0.339, p=0.009, respectively).

CONCLUSIONS

Both systolic and diastolic functions were significantly deteriorated after chemotherapy. In addition, plasma levels of HA and troponin increased after treatment. Further, both systolic and diastolic dysfunctions were found to correlate with serum HA levels. All these data suggest that HA might have a function on anthracycline-induced cardiotoxicity.

Cardiovascular imaging in the diagnosis and monitoring of cardiotoxicity: role of echocardiography

The evaluation by cardiovascular imaging of chemotherapy patients became a central topic in the last several years. The use of drugs for the treatment of cancers increased, and new molecules and protocols were developed to improve outcomes in these patients. Although, these novel approaches also produced a progressive increase in side effects, particularly myocardial dysfunction. Imaging of the heart was highly accurate in the early diagnosis of cancer therapeutics related-cardiac dysfunction. Echocardiography is the first-line method to assess ventricular function alterations, and it is required to satisfy the need for an early, easy and accurate diagnosis to stratify the risk of heart failure and manage treatments. A careful monitoring of cardiac function during the course of therapy should prevent the onset of severe heart impairment. This review provides an overview of the most important findings of the role of echocardiography in the management of chemotherapy-treated patients to create a clear and complete description of the efficacy of conventional measurements, the importance of comprehensive heart evaluations, the additional role of new echocardiographic techniques, the utility of integrated studies using other imaging tools and the positions of the most important international societies on this topic.

Heart Failure Therapies for End-Stage Chemotherapy-Induced Cardiomyopathy

With ongoing advancements in cancer-related treatments, the number of cancer survivors continues to grow globally, with numbers in the United States predicted to reach 18 million by 2020. As a result, it is expected that a greater number of patients will present with chemotherapy-related side effects. One entity in particular, chemotherapy-related cardiomyopathy (CCMP), is a known cardiotoxic manifestation associated with agents such as anthracyclines, trastuzumab, and tyrosine kinase inhibitors. Although such effects have been described in the medical literature for decades, concrete strategies for screening, prevention, and management of CCMP continue to be elusive owing to limited studies. Late recognition of CCMP is associated with a poorer prognosis, including a lack of clinical response to pharmacologic therapy, and end-stage heart failure. A number of advanced cardiac therapies, including cardiac resynchronization therapy, ventricular assist devices, and orthotopic cardiac transplantation, are available to for end-stage heart failure; however, the role of these therapies in CCMP is unclear. In this review, management of end-stage CCMP with the use of advanced therapies and their respective effectiveness are discussed, as well as clinical characteristics of patients undergoing these treatments. The relative paucity of data in this field highlights the importance and need for larger-scale longitudinal studies and long-term registries tracking the outcomes of cancer survivors who have received cardiotoxic cancer therapy to determine the overall incidence of end-stage CCMP, as well as prognostic factors that will ultimately guide such patients toward receiving appropriate end-stage care.

Anthracycline-Induced Cardiomyopathy in Adults

Anthracyclines are one of the most commonly used antineoplastic agent classes, and a core part of the treatment in breast cancers, hematological malignancies, and sarcomas. Their benefit is decreased by their well-recognized cardiotoxicity. The purpose of this review is to outline the presentation, mechanisms, diagnosis, and treatment of anthracyclines-induced cardiotoxicity. Symptomatic heart failure occurs in 2% to 5% of patients treated with anthrayclines and may be higher in older patients or patients with cardiovascular risk factors. The mechanisms involved in anthracycline-induced cardiotoxicity involve myocyte loss by apoptosis in the presence of a limited regenerative capacity. Once symptomatic, anthracycline-induced cardiotoxicity is associated with markedly decreased survival. Left ventricular ejection fraction (LVEF), mostly determined using echocardiography, is used to monitor patients treated with anthracyclines. As more than 1/3 of patients treated with anthracyclines do not recover their baseline LVEF once it is decreased, more sensitive echocardiographic indices of LV function such as myocardial deformation or biomarkers have been studied in patients monitoring. Cardioprotective treatments such as angiotensin-converting enzyme inhibitors, beta-blockers, iron chelators, statins, and metformin are also the topic of research efforts.

Management of Advanced Heart Failure due to Cancer Therapy: the Present Role of Mechanical Circulatory Support and Cardiac Transplantation

OPINION STATEMENT

Rapid improvement in antineoplastic therapy is increasing not only cancer survivorship but also the incidence of end-stage heart failure among breast and childhood cancer survivors. Anthracyclines and newer targeted therapies, including trastuzumab and tyrosine kinase inhibitors, are important agents implemented in clinical practice that carry cardiotoxic risk. While acute heart failure is often self-limited and reversible, delayed-onset heart failure significantly reduces survival. Extremes of age, renal dysfunction, pre-existing coronary artery disease, HER2 positivity, and multi-drug therapy are predictors of irreversible heart failure after chemotherapy. Left ventricular assist device (LVAD) implantation and cardiac transplantation can be performed safely in patients with end-stage heart failure (HF) from chemotherapy. However, co-existing right ventricular dysfunction, hepatic congestion, and increased risk of bleeding make LVAD therapy challenging and dependent on careful patient selection. Cardiac transplantation in patients with chemotherapy-induced heart failure can be performed with good 10-year survival, but requires 5 years of cancer freedom and post-transplant infections remain a problem. Improvements in LVAD therapy and the expanding role of the total artificial heart and other durable biventricular support devices will likely provide more reliable surgical options for the management of end-stage HF after chemotherapy.

Subclinical ventricular dysfunction detected by speckle tracking two years after use of anthracycline

Background

Heart failure is a severe complication associated with doxorubicin (DOX) use. Strain, assessed by two-dimensional speckle tracking (2D-STE), has been shown to be useful in identifying subclinical ventricular dysfunction.

Objectives

a) To investigate the role of strain in the identification of subclinical ventricular dysfunction in patients who used DOX; b) to investigate determinants of strain response in these patients.

Methods

Cross-sectional study with 81 participants: 40 patients who used DOX ±2 years before the study and 41 controls. All participants had left ventricular ejection fraction (LVEF) ≥55%. Total dose of DOX was 396mg (242mg/ms²). The systolic function of the LV was evaluated by LVEF (Simpson), as well as by longitudinal (ε_LL), circumferential (ε_CC), and radial (ε_RR) strains. Multivariate linear regression (MLR) analysis was performed using ε_LL (model 1) and ε_CC (model 2) as dependent variables.

Results

Systolic and diastolic blood pressure values were higher in the control group (p < 0.05). ε_LL was lower in the DOX group (-12.4 ±2.6%) versus controls (-13.4 ± 1.7%; p = 0.044). The same occurred with ε_CC: -12.1 ± 2.7% (DOX) versus -16.7 ± 3.6% (controls; p < 0.001). The S’ wave was shorter in the DOX group (p = 0.035). On MLR, DOX was an independent predictor of reduced ε_CC (B = -4.429, p < 0.001). DOX (B = -1.289, p = 0.012) and age (B = -0.057, p = 0.029) were independent markers of reduced ε_LL.

Conclusion

a) ε_LL, ε_CC and the S’ wave are reduced in patients who used DOX ±2 years prior to the study despite normal LVEF, suggesting the presence of subclinical ventricular dysfunction; b) DOX was an independent predictor of reduced ε_CC; c) prior use of DOX and age were independent markers of reduced ε_LL.

Cardiomyopathy associated with cancer therapy

Chemotherapy-associated cardiomyopathy is a well known cardiotoxicity of contemporary cancer treatment and a cause of increasing concern for both cardiologists and oncologists. As cancer outcomes improve, cardiovascular disease has become a leading cause of morbidity and mortality among cancer survivors. Asymptomatic or symptomatic left ventricular systolic dysfunction in the setting of cardiotoxic chemotherapy is an important entity to recognize. Early diagnosis of cardiac injury through the use of novel blood-based biomarkers or noninvasive imaging modalities may allow for the initiation of cardioprotective medications or modification of chemotherapy regimen to minimize or prevent further damage. Several clinical trials are currently underway to determine the efficacy of cardioprotective medications for the prevention of chemotherapy-associated cardiomyopathy. Implementing a strategy that includes both early detection and prevention of cardiotoxicity will likely have a significant impact on the overall prognosis of cancer survivors. Continued coordination of care between cardiologists and oncologists remains critical to maximizing the oncologic benefit of cancer therapy while minimizing any early or late cardiovascular effects.

Potential genetic predisposition for anthracycline-associated cardiomyopathy in families with dilated cardiomyopathy

Objective

Anthracyclines are successfully used in cancer treatment, but their use is limited by their cardiotoxic side effects. Several risk factors for anthracycline-associated cardiomyopathy (AACM) are known, yet the occurrence of AACM in the absence of these known risk factors suggests that other factors must play a role. The purpose of this study was to evaluate whether a genetic predisposition for dilated cardiomyopathy (DCM) could be a potential risk factor for AACM.

Methods

A hospital-based registry of 162 DCM families and two hospital-based registries of patients with cancer treated with systemic cancer therapy (n>6000) were reviewed focusing on AACM. Selected patients with AACM/DCM families with possible AACM (n=21) were analysed for mutations in cardiomyopathy-associated genes and presymptomatic cardiological evaluation of first-degree relatives was performed.

Results

We identified five DCM families with AACM and one patient with AACM with a family member with a possible early sign of mild DCM. Pathogenic MYH7 mutations were identified in two of these six families. The MYH7 c.1633G>A (p.Asp545Asn) and c.2863G>A (p.Asp955Asn) mutations (one double mutant allele) were identified in a DCM family with AACM. The MYH7 c.4125T>A (p.Tyr1375X) mutation was identified in one patient with AACM.

Conclusions

This study further extends the hypothesis that a genetic predisposition to DCM could be a potential risk factor for AACM.

Are cardiac magnetic resonance imaging and radionuclide ventriculography good options against echocardiography for evaluation of anthracycline induced chronic cardiotoxicity in childhood cancer survivors?

Anthracyclines are widely used for the treatment of solid tumors in pediatric oncology. However, their uses may be limited by progressive chronic cardiotoxicity related to the cumulative dosage. The aims of this study are to compare diagnostic techniques and prepare an algorithm for diagnosis of anthracycline induced chronic cardiotoxicity. The patients were evaluated according to age, sex, time elapsed since the last dose of anthracycline treatment, presence of cardiovascular symptoms, follow-up duration, type of anthracycline, cumulative anthracycline dose, and concomitant mediastinal radiation therapy. Late subclinical cardiotoxicity was detected by history, physical examination, electrocardiography (ECG), Holter monitor, echocardiography (ECHO), radionuclide ventriculography (MUGA), and cardiac magnetic resonance imaging (MRI). Thirty-seven male and 19 female patients with a median age of 11.2 ± 4.6 (range, 3.5-22.0) years were included in the study. Patients were grouped according to cumulative anthracycline doses. Subclinical cardiac dysfunction was detected in 20 patients by at least one of ECHO, MRI or MUGA after anthracycline chemotherapy. We revealed that other than ECHO, MRI and MUGA have high clinical importance for evaluating subclinical late cardiac complications in children treated with anthracyclines.

Catching broken hearts: pre-clinical detection of doxorubicin and trastuzumab mediated cardiac dysfunction in the breast cancer setting

Although breast cancer is one of the leading causes of death in women worldwide, there is an overall improvement in the survival of this patient population. This is likely due to a combination of early detection through screening and awareness, improved targeted biological therapy, and an overall improvement in disease management. Despite the beneficial effects of the 2 anti-cancer drugs doxorubicin (DOX) and trastuzumab (TRZ) in women with breast cancer, development of cardiotoxicity is a major concern. The occurrence of left ventricular systolic dysfunction is unacceptably high in nearly 1 in 4 women treated with DOX+TRZ in the breast cancer setting. In this review, we explore the use of non-invasive cardiac imaging for the early detection of chemotherapy-mediated cardiotoxicity in women with breast cancer, in the hope of preventing end-stage heart disease in this cancer population.

Molecular basis of cancer-therapy-induced cardiotoxicity: introducing microRNA biomarkers for early assessment of subclinical myocardial injury

Development of reliable biomarkers for early clinical assessment of drug-induced cardiotoxicity could allow the detection of subclinical cardiac injury risk in vulnerable patients before irreversible damage occurs. Currently, it is difficult to predict who will develop drug-induced cardiotoxicity owing to lack of sensitivity and/or specificity of currently used diagnostics. miRNAs are mRNA regulators and they are currently being extensively profiled for use as biomarkers due to their specific tissue and disease expression signature profiles. Identification of cardiotoxicity-specific miRNA biomarkers could provide clinicians with a valuable tool to allow prognosis of patients at risk of cardiovascular injury, alteration of a treatment regime or the introduction of an adjunct therapy in order to increase the long-term survival rate of patients treated with cardiotoxic drugs.

Biomarkers for the early detection of anthracycline-induced cardiotoxicity: current status

BACKGROUND

Cardiotoxicity is a well-known and potentially serious complication of anticancer therapy. Anthracycline-based chemotherapy represents the greatest risk. Early detection of cardiotoxicity is crucial for applying preventive and supportive therapeutic strategies.

METHODS AND RESULTS

Various methods have been recommended for monitoring of cardiotoxicity. In our conditions, echocardiography and electrocardiography are routinely used. However, this approach shows low sensitivity for the early prediction of cardiomyopathy when the possibilities of appropriate management could still improve the patient's outcome. Recently, biomarkers of cardiac injury have been investigated in the assessment of chemotherapy-induced cardiotoxicity. Cardiospecific biomarkers, such as cardiac troponins, show high diagnostic efficacy in the early subclinical phase of the disease before the clinical onset of cardiomyopathy. Increase in their concentrations correlates with disease severity. As for natriuretic peptides, some studies, including ours, have shown promising results. Definitive evidence of their diagnostic and prognostic role in this context is still lacking and natriuretic peptides have not been routinely used for monitoring of cardiotoxicity in clinical practice. Other perspective biomarkers of cardiotoxicity in oncology are under study, especially heart-type fatty acid-binding protein (H-FABP) and glycogen phosphorylase BB (GPBB). Our studies using GPBB have provided encouraging results. However, the available data are limited and their practical use in this context cannot be recommended until their clinical efficacy is clearly defined.

CONCLUSIONS

This review covers the current status of biomarkers for the early detection of anthracycline-induced cardiotoxicity. The authors present in brief, their own experience with multiple biomarkers in the detection of cardiotoxicity.

Understanding cardiovascular injury after treatment for cancer: an overview of current uses and future directions of cardiovascular magnetic resonance

While cancer-free survival has improved over the past 20 years for many individuals with prostate, renal, breast, and hematologic malignancies, the increasingly recognized prevalence of cardiovascular (CV) events in cancer survivors has been an unintended consequence of many of the therapies that have improved these survival rates. The increase in CV events threatens to offset the improvement in cancer related survival. As a result, there is an emerging need to develop methods to identify those individuals treated for cancer at increased risk of cardiovascular events. With its inherent ability to characterize myocardial tissue and identify both cardiac and vascular dysfunction, cardiovascular magnetic resonance (CMR) has the potential to identify both subclinical and early clinical CV injury before the development of an overt catastrophic event such as a myocardial infarction, stroke, or premature cardiac death. Early identification provides an opportunity for the implementation of primary prevention strategies to prevent such events, thereby improving overall cancer survivorship and quality of life. This article reviews the etiology of CV events associated with cancer therapy and the unique potential of CMR to provide early diagnosis of subclinical CV injury related to the administration of these therapies.

Managing cardiotoxicity of chemotherapy

OPINION STATEMENT

The increase in survivorship of cancer patients makes the understanding of the available options for prevention and treatment of cardiotoxicity induced by antineoplastic agents a crucial topic both for cardiologists and oncologists. The most frequent and typical clinical manifestation of cardiotoxicity is asymptomatic or symptomatic left ventricular dysfunction, which may progress to overt heart failure. It may be induced not only by conventional cancer therapy, like anthracyclines, but also by new antitumoral targeted therapy such as trastuzumab. The current standard for monitoring cardiac damage during antineoplastic treatment, mainly based on the quantification of left ventricular ejection fraction, detects cardiac toxicity only when a functional impairment has already occurred. Evaluation of cardiac biomarkers such as troponin, however, has shown excellent sensitivity in the early detection of cardiotoxicity by the identification of patients with subclinical cardiac injury that precedes the development of cardiac dysfunction. The use of angiotensin-converting enzyme inhibitors in patients with troponin elevation during chemotherapy may be an effective tool to prevent left ventricular ejection fraction reduction and late cardiac events. There are no well established recommendations for treatment of cancer patients who develop cardiac dysfunction. Angiotensin-converting enzyme inhibitors and beta-blockers have proven to be effective in this setting. However, there are concerns in using these medications in cancer patients, and therefore the tendency is to treat patients only if symptomatic. However, the clinical benefit of these medications may be more evident in asymptomatic patients, and the recovery of cardiac function strongly depends on the amount of time elapsed from the end of chemotherapy to the start of heart failure therapy. This observation suggests that the early detection of cardiac damage is crucial and early use of angiotensin-converting enzyme inhibitors and beta-blockers should be considered in patients with left ventricular dysfunction induced by antineoplastic agents.

Noninvasive diagnosis of chemotherapy related cardiotoxicity

Chemotherapeutic agents reduce mortality and can prevent morbidity in a wide range of malignancies. These agents are, however, associated with toxicities of their own, and the treating physician must remain ever vigilant against the risk outgrowing the benefit of therapy. Thus, pre-treatment evaluation and monitoring for toxicity during and following administration is a fundamental tenet of oncologic practice. Among the most insidious and deadly toxicities of anti-tumor agents is cardiac toxicity, which in some cases may be irreversible. Early detection of cardiotoxicity allows the treating oncologist to redirect therapy or dose modify, taking into account the cost of a reduction in therapy against the potential of further injury to the patient. In these instances, the role of the cardiologist is to assist and advise the oncologist by providing diagnostic and prognostic information regarding developing cardiotoxicity. This review discusses noninvasive diagnostic options to identify and characterize cardiotoxicity and their use in prognosis and guiding therapy. We also review established protocols for cardiac safety monitoring in the treatment of malignancy.

Garlic and cardioprotection: insights into the molecular mechanisms

Garlic is widely recognized for its immense therapeutic potential. Garlic has been shown to exert its beneficial effects against a wide spectrum of diseases, including cancer, diabetes, and microbial infections, as well as immunological and cardiovascular disorders. Most of the research on garlic has indicated that garlic and its active compounds are effective in reducing cardiovascular and metabolic risk by normalizing abnormal plasma lipids, oxidized low density lipoproteins, abnormal platelet aggregation, high blood pressure, and cardiac injury. Some of the beneficial effects of dietary garlic against cardiovascular disorders are mediated via the generation of hydrogen sulfide and nitric oxide in cardiomyocytes and endothelial cells. Garlic has the potential to protect the heart against myocardial infarction, doxorubicin-induced cardiotoxicity, arrhythmia, hypertrophy, and ischemia-reperfusion injury. The induction of cardiac endogenous antioxidants and the reduction of lipid peroxidation by garlic has been reported by several different groups. Other mechanisms, such as regulating ion channels, modulating Akt signaling pathways, histone deacetylase inhibition, and cytochrome P450 inhibition, could be responsible for the cardioprotective effect of garlic. Although several mechanisms have been identified for the cardioprotective effect of garlic, there is a need for further research to identify the specific molecular mechanism of cardioprotection in different cardiac diseases.

Cardiotoxicity After Anthracycline Treatment in Survivors of Adult Cancers: Monitoring by USCOM, Echocardiography and Serum Biomarkers

Background

Anthracyclines are agents with a well known documented anti-tumoral activity. Cardiac side effects are the principal toxicity. Here we evaluate and monitor the onset of late anthracycline-induced cardiotoxicity with real-time CW-Doppler ultrasound cardiac output monitoring (USCOM®) and echocardiography in combination with serum biomarkers.

Methods

Fifty-two patients without cardiac disease who had received an anthracycline-based regimen for various cancer types were included in this study. Patients’ hemodynamic parameters as stroke volume (SV USCOM (mL)) and ejection fraction (EF ECHOCARDIOGRAPHY (%)) were measured with USCOM and echocardiography and correlated to serum biomarkers (NT-pro-BNP and cTnT).

Results

Eighteen patients (34.6%) developed cardiac disease (NYHA I-III). An increasing cumulative anthracycline dose was associated with a decrease of the EF determined by echocardiography as well the SV by USCOM and with a higher NYHA class. Those patients who experienced cardiac disease showed a reduction of the EF and SV and increased serum biomarkers.

Conclusions

Real-time CW-Doppler USCOM, is a fast and reliable method to monitor late hemodynamic changes as a symptom of anthracycline-induced cardiotoxicity comparable to the findings by echocardiography and serum biomarkers.

Current applications of cardiac troponin T for the diagnosis of myocardial damage

Biochemical markers of myocardial injury play an important role in the diagnosis of cardiovascular diseases. Measurement of cardiac biomarkers is one of the most important diagnostic tests in acute myocardial infarction (AMI), heart failure, and other cardiovascular disorders. Recently, the European Society of Cardiology, the American College of Cardiology Foundation, the American Heart Association, and the World Heart Federation have published a consensus definition of AMI that includes a detailed guideline for the assessment of biochemical markers in suspected disease. The cardiac troponins (cTI and cTnT) were recommended as preferred markers of myocardial necrosis in this setting. Herein, we review cardiac troponin biochemistry, the performance characteristics of cTnT assays, and optimal utilization of troponin in patients with proven or possible cardiovascular disease. We also discuss the use of troponin tests, with emphasis on cTnT, in different clinical situations in which its levels may be elevated.

Use of echocardiography to evaluate the cardiac effects of therapies used in cancer treatment: what do we know?

Cardiologists and oncologists today face the daunting challenge of identifying patients at risk for late-onset left ventricular (LV) systolic dysfunction from the use of various chemotherapeutic agents. Currently, the most widely used method in clinical practice for monitoring the potential of chemotherapy-induced cardiotoxicity is calculation of LV ejection fraction. The use of LV ejection fraction to determine whether to continue or discontinue the use of chemotherapeutic agents is limited, because decreases in LV ejection fraction frequently occur late and can be irreversible. These limitations have led to the exploration of diastolic function and newer modalities that assess myocardial mechanics to identify sensitive and specific variables that can predict the occurrence of late systolic function. The cancer therapies associated with cardiotoxicity are reviewed in this report. Additionally, the authors evaluate the role of present-day echocardiographic parameters, complementary noninvasive imaging modalities, and biomarkers in the prediction of cardiotoxicity. The authors address the evolving role of cardioprotective agents and potential therapies to prevent or reverse the progression of LV systolic dysfunction. Finally, they provide some ideas regarding future directions to enhance the knowledge of predicting late-onset LV systolic dysfunction secondary to cancer therapy.

Biomarkers and early detection of late onset anthracycline-induced cardiotoxicity in children

BACKGROUND

The main strategy for minimizing anthracycline cardiotoxicity is early detection of high-risk patients.

AIM OF THE STUDY

To investigate the role of cardiac biomarkers; cardiac troponin T (cTnT) and N-terminal probrain natriuretic peptide (NT-pro-BNP), and tissue Doppler imaging (TDI), as early predictors of chronic cardiotoxicity in survivors of acute leukemia.

PATIENTS AND METHODS

We carried a retrospective study on 50 asymptomatic survivors of acute leukemia who received anthracycline in their treatment protocols. All patients underwent blood sampling to determine the levels of NT-pro-BNP and cTnT along with conventional echocardiography and TDI.

RESULTS

None had abnormal cTnT levels. About 20% had abnormal NT-pro-BNP levels. Diastolic dysfunction of the left ventricle was the most significant in conventional echocardiography. TDI was superior as it detected myocardial affection in 10% more than echo. TDI demonstrated global myocardial damage with significant aberrations in peak myocardial velocities and ratios.

CONCLUSIONS

NT-pro-BNP can be used as a sensitive cardiac biomarker in monitoring of anthracycline-induced cardiotoxicity. Follow up is essential to validate the role of NT-pro-BNP as an early marker for late onset anthracycline-induced cardiotoxicity. Tissue Doppler is marvelous as it could detect early cardiac dysfunction even in those with normal study by conventional echocardiography.

Anthracycline-induced cardiotoxicity: cardiac monitoring by continuous wave-Doppler ultrasound cardiac output monitoring and correlation to echocardiography

BACKGROUND

Anthracyclines are agents with a wellknown cardiotoxicity. The study sought to evaluate the hemodynamic response to an anthracycline using realtime continuous-wave (CW)-Doppler ultrasound cardiac output monitoring (USCOM) and echocardiography in combination with serum biomarkers.

METHODS

50 patients (26 male, 24 female, median age 59 years) suffering from various types of cancer received an anthracycline-based regimen. Patients' responses were measured at different time points (T0 prior to infusion, T1 6 h post infusion, T2 after 1 day, T3 after 7 days, and T4 after 3 months) with CW-Doppler ultrasound (T0-T4) and echocardiography (T1, T4) for hemodynamic parameters such as stroke volume (SV; SVUSCOM ml) and ejection fraction (EF; EFechocardiography%) and with NT-pro-BNP and hs-Troponin T (T0-T4).

RESULTS

During the 3-month observation period, the relative decrease in the EF determined by echocardiography was -2.1% (▵T0-T4, T0 71 ± 7.8%, T4 69.5 ± 7%, p = 0.04), whereas the decrease in SV observed using CW-Doppler was -6.5% (▵T0-T4, T0 54 ± 19.2 ml, T4 50.5 ± 20.6 ml, p = 0.14). The kinetics for serum biomarkers were inversely correlated.

CONCLUSIONS

Combining real-time CW-Doppler USCOM and serum biomarkers is feasible for monitoring the immediate and chronic hemodynamic changes during an anthracycline-based regimen; the results obtained were comparable to those from echocardiography.

Mitochondria death/survival signaling pathways in cardiotoxicity induced by anthracyclines and anticancer-targeted therapies

Anthracyclines remain the cornerstone of treatment in many malignancies but these agents have a cumulative dose relationship with cardiotoxicity. Development of cardiomyopathy and congestive heart failure induced by anthracyclines are typically dose-dependent, irreversible, and cumulative. Although past studies of cardiotoxicity have focused on anthracyclines, more recently interest has turned to anticancer drugs that target many proteins kinases, such as tyrosine kinases. An attractive model to explain the mechanism of this cardiotoxicity could be myocyte loss through cell death pathways. Inhibition of mitochondrial transition permeability is a valuable tool to prevent doxorubicin-induced cardiotoxicity. In response to anthracycline treatment, activation of several protein kinases, neuregulin/ErbB2 signaling, and transcriptional factors modify mitochondrial functions that determine cell death or survival through the modulation of mitochondrial membrane permeability. Cellular response to anthracyclines is also modulated by a myriad of transcriptional factors that influence cell fate. Several novel targeted chemotherapeutic agents have been associated with a small but worrying risk of left ventricular dysfunction. Agents such as trastuzumab and tyrosine kinase inhibitors can lead to cardiotoxicity that is fundamentally different from that caused by anthracyclines, whereas biological effects converge to the mitochondria as a critical target.

Assessment of cardiotoxicity with cardiac biomarkers in cancer patients

Cardiotoxicity remains a major limitation of chemotherapy, strongly affecting the quality of life and the overall survival of cancer patients, regardless of their oncologic prognosis. The time elapsed from the end of cancer therapy to the beginning of heart failure therapy for chemotherapy-induced cardiac dysfunction is an important determinant of the extent of recovery. This highlights the need for a real-time diagnosis of cardiac injury. The current standard for monitoring cardiac function detects cardiotoxicity only when a functional impairment has already occurred, precluding any chance of preventing its development. In the last decade, early identification, assessment, and monitoring of cardiotoxicity, by measurement of serum cardiospecific biomarkers, have been proposed as an effective alternative. In particular, the role of troponin I in identifying patients at risk for cardiotoxicity and of angiotensin-converting enzyme inhibitors in preventing left ventricular ejection fraction reduction and cardiac events has clearly proved to be an effective strategy for this complication. In addition, novel biomarkers for the identification of cardiotoxicity are emerging. The use of a multimarker approach may provide a unique opportunity for advancement in this field, allowing for better stratification of the cardiac risk in cancer patients treated with anticancer drugs.

Routine cardiac evaluation in patients with early-stage breast cancer before adjuvant chemotherapy

INTRODUCTION

This population-based study of women diagnosed with early-stage breast cancer aimed to (i) determine the current utilization pattern of multigated acquisition (MUGA) scans before adjuvant chemotherapy (AdjC) treatment, and (ii) examine the impact of MUGA scan results on AdjC decision making.

METHODS

All women who underwent curative-intent surgery for stage I-III breast cancer between October 2005 and September 2006 in Nova Scotia, Canada, were identified through the provincial cancer registry. A retrospective chart review was performed to abstract all relevant clinical-pathologic variables, including baseline cardiac risk factors. The association between MUGA scan utilization and clinical-pathologic variables, as well as receipt and type of AdjC, was examined through univariate and multivariate analyses.

RESULTS

The study included 593 women, of whom 238 (40%) received AdjC (94% anthracycline vs. 6% nonanthracycline) and 198 (33%) underwent baseline MUGA scans. Of those received AdjC, 80% underwent MUGA scans. MUGA scan utilization was associated with AdjC treatment (yes vs. no; P < .0001), Her-2/neu status (positive vs. negative vs. not tested; P < .0001), and AdjC regimen (anthracycline vs. nonanthracycline; P < .0001). Abnormal MUGA results were observed in 5 (2.5%) of 198; all were smokers, and 4 were >65 years of age. In the 1 patient <50 years old, subsequent echocardiograms indicated normal cardiac function.

CONCLUSIONS

Routine baseline MUGA scans before AdjC were abnormal and changed the AdjC treatment decision in only 2.5% and 2.0% of patients, respectively. Routine MUGA scans before anthracycline-based AdjC without trastuzumab, however, did not influence AdjC decisions for younger patients <65 years of age without underlying cardiac risk factors.

Current status of endomyocardial biopsy

Endomyocardial biopsy (EMB) is widely used for surveillance of cardiac allograft rejection and for the diagnosis of unexplained ventricular dysfunction. Typically, EMB is performed through the jugular or femoral veins and is associated with a serious acute complication rate of less than 1% using current flexible bioptomes. Although it is accepted that EMB should be used to monitor for rejection after transplant, use of EMB for the diagnosis of various myocardial diseases is controversial. Diagnosis of myocardial disease in the nontransplant recipient is often successful via noninvasive investigations including laboratory evaluation; echocardiography, nuclear studies, and magnetic resonance imaging can yield specific diagnoses in the absence of invasive EMB. Therefore, use of the technique is patient specific and depends on the potential prognostic and treatment information gained by establishing a pathologic diagnosis beyond noninvasive testing.

The value of echocardiography versus cardiac troponin I levels in the early detection of anthracycline cardiotoxicity in childhood acute leukemia: prospective evaluation of a 7-year-long clinical follow-up

The present study was designed to evaluate the significance of echocardiography versus cardiac troponin I levels in early detection of anthracycline dependent cardiotoxicity in acute lymphoblastic leukemia (ALL) patients. A total of 276 pediatric ALL patients were included in the study prospectively along 3 phases of data collection lasted from 2002 to 2009; including phase I (March 2002 to February 2003; n = 25; 53.3% females), phase II (September 2003 to April 2004; n = 35; 57.1% females), and phase III (January 2005 to June 2009; n = 216; 52.7% females) with respect to cumulative anthracycline doses applied. Anthracycline was administered in accordance with berlin-Franfurt-Munich (BFM)-2000 protocol in doses of 30 to 350 mg/m(2) (in the first phase) and 30 to 240 mg/m(2) (in the following phases). Evaluation of cardiotoxicity was performed via echocardiography and measurement of cardiac troponin I levels. Patients in each phase were homogenous in terms of gender and age. Diastolic dysfunction determined via reduction E/A ratio below the cutoff value was demonstrated to deteriorate earlier than systolic functions and alteration in cardiac enzymes. Being similar between dose groups, cTnI levels were shown to rise in the presence of congestive heart failure. In conclusion, anthracycline cardiotoxicity appears to be detected in an earlier stage by using diastolic parameters compared to systolic parameters and cardiac enzymes.