Subclinical cardiotoxic effects of anthracyclines as assessed by magnetic resonance imaging-a pilot study

Relationship between cardiac mechanical properties and cardiac magnetic resonance imaging at rest in childhood acute lymphoblastic leukemia survivors

The characterization of cardiac mechanical properties may contribute to better understanding of doxorubicin-induced cardiotoxicity. Our study aims to investigate the relationship between cardiac mechanical properties, T1 and T2 relaxation times and partition coefficient. Fifty childhood acute lymphoblastic leukemia survivors underwent a cardiac magnetic resonance (CMR) at rest on a 3T MRI system and included a standard ECG-gated 3(3)3(3)5 MOLLI sequence for T1 mapping and an ECG-gated T2-prepared TrueFISP sequence for T2 mapping. Partition coefficient, ejection fraction, end-diastolic volume (EDV) and end-systolic volume (ESV) were calculated. CircAdapt model was used to study cardiac mechanical performance (left ventricle stiffness (LVS), contractility (LVC) and pressure (Pmin and Pmax), cardiac work efficiency (CWE) and ventricular arterial coupling). In the whole cohort, our results showed that LVC (R2 = 69.2%, r = 0.83), Pmin (R2 = 62.9%, r = 0.79) and Pmax can be predicted by significant CMR parameters, while T1 (R2 = 23.2%, r = 0.48) and partition coefficient (R2 = 13.8%, r = 0.37) can be predicted by significant cardiac mechanical properties. In SR group LVS (R2 = 94.8%, r = 0.97), LVC (R2 = 93.7%, r = 0.96) and Pmin (R2 = 90.6%, r = 0.95) can be predicted by significant cardiac mechanical properties, while in HR + DEX group CWE (R2 = 49.8%, r = 0.70) can be predicted by significant cardiac mechanical properties. Partition coefficient (R2 = 72.6%, r = 0.85) can be predicted by significant CMR parameters in SR group. Early characterization of cardiac mechanical properties from CMR parameters has the potential to early detect doxorubicin-induced cardiotoxicity.

Multimodality imaging in cardio-oncology: the added value of CMR and CCTA

During the last 30 years, we have assisted to a great implementation in anticancer treatment with a subsequent increase of cancer survivors and decreased mortality. This has led to an ongoing interest about the possible therapy-related side-effects and their management to better guide patients therapy and surveillance in the chronic and long-term setting. As a consequence cardio-oncology was born, involving several different specialties, among which radiology plays a relevant role. Till the end of August 2022, when European Society of Cardiology (ESC) developed the first guidelines on cardio-oncology, no general indications existed to guide diagnosis and treatment of cancer therapy-related cardiovascular toxicity (CTR-CVT). They defined multimodality imaging role in primary and secondary prevention strategies, cancer treatment surveillance and early CTR-CVT identification and management. Cardiac computed tomography angiography (CCTA) has acquired a central role in coronary assessment, as far as coronary artery disease (CAD) exclusion is concerned; but on the side of this well-known application, it also started to be considered in left ventricular function evaluation, interstitial fibrosis quantification and cardiac perfusion studies. Cardiac magnetic resonance (CMR), instead, has been acknowledged as the gold standard alternative to trans-thoracic echocardiography (TTE) poor acoustic window in quantification of heart function and strain modifications, as well as pre- and post-contrast tissue characterization by means of T1-T2 mapping, early Gadolinium enhancement (EGE), late Gadolinium enhancement (LGE) and extracellular volume (ECV) evaluation. Our review is intended to provide a focus on the actual role of CMR and CCTA in the setting of a better understanding of cardiotoxicity and to draw some possible future directions of cardiac imaging in this field, starting from the recently published ESC guidelines.

The Role of Advanced Cardiovascular Imaging Modalities in Cardio-Oncology: From Early Detection to Unravelling Mechanisms of Cardiotoxicity

Advances in cancer therapies have led to a global improvement in patient survival rates. Nevertheless, the price to pay is a concomitant increase in cardiovascular (CV) morbidity and mortality in this population. Increased inflammation and disturbances of the immune system are shared by both cancer and CV diseases. Immunological effects of anti-cancer treatments occur with both conventional chemotherapy and, to a greater extent, with novel biological therapies such as immunotherapy. For these reasons, there is growing interest in the immune system and its potential role at the molecular level in determining cardiotoxicity. Early recognition of these detrimental effects could help in identifying patients at risk and improve their oncological management. Non-invasive imaging already plays a key role in evaluating baseline CV risk and in detecting even subclinical cardiac dysfunction during surveillance. The aim of this review is to highlight the role of advanced cardiovascular imaging techniques in the detection and management of cardiovascular complications related to cancer treatment.

Comprehensive Cardiovascular Magnetic Resonance Tissue Characterization and Cardiotoxicity in Women With Breast Cancer

Importance

There is a growing interest in understanding whether cardiovascular magnetic resonance (CMR) myocardial tissue characterization helps identify risk of cancer therapy-related cardiac dysfunction (CTRCD).

Objective

To describe changes in CMR tissue biomarkers during breast cancer therapy and their association with CTRCD.

Design, Setting, and Participants

This was a prospective, multicenter, cohort study of women with ERBB2 (formerly HER2)-positive breast cancer (stages I-III) who were scheduled to receive anthracycline and trastuzumab therapy with/without adjuvant radiotherapy and surgery. From November 7, 2013, to January 16, 2019, participants were recruited from 3 University of Toronto-affiliated hospitals. Data were analyzed from July 2021 to June 2022.

Exposures

Sequential therapy with anthracyclines, trastuzumab, and radiation.

Main Outcomes and Measures

CMR, high-sensitivity cardiac troponin I (hs-cTnI), and B-type natriuretic peptide (BNP) measurements were performed before anthracycline treatment, after anthracycline and before trastuzumab treatment, and at 3-month intervals during trastuzumab therapy. CMR included left ventricular (LV) volumes, LV ejection fraction (EF), myocardial strain, early gadolinium enhancement imaging to assess hyperemia (inflammation marker), native/postcontrast T1 mapping (with extracellular volume fraction [ECV]) to assess edema and/or fibrosis, T2 mapping to assess edema, and late gadolinium enhancement (LGE) to assess replacement fibrosis. CTRCD was defined using the Cardiac Review and Evaluation Committee criteria. Fixed-effects models or generalized estimating equations were used in analyses.

Results

Of 136 women (mean [SD] age, 51.1 [9.2] years) recruited from 2013 to 2019, 37 (27%) developed CTRCD. Compared with baseline, tissue biomarkers of myocardial hyperemia and edema peaked after anthracycline therapy or 3 months after trastuzumab initiation as demonstrated by an increase in mean (SD) relative myocardial enhancement (baseline, 46.3% [16.8%] to peak, 56.2% [18.6%]), native T1 (1012 [26] milliseconds to 1035 [28] milliseconds), T2 (51.4 [2.2] milliseconds to 52.6 [2.2] milliseconds), and ECV (25.2% [2.4%] to 26.8% [2.7%]), with P <.001 for the entire follow-up. The observed values were mostly within the normal range, and the changes were small and recovered during follow-up. No new replacement fibrosis developed. Increase in T1, T2, and/or ECV was associated with increased ventricular volumes and BNP but not hs-cTnI level. None of the CMR tissue biomarkers were associated with changes in LVEF or myocardial strain. Change in ECV was associated with concurrent and subsequent CTRCD, but there was significant overlap between patients with and without CTRCD.

Conclusions and Relevance

In women with ERBB2-positive breast cancer receiving sequential anthracycline and trastuzumab therapy, CMR tissue biomarkers suggest inflammation and edema peaking early during therapy and were associated with ventricular remodeling and BNP elevation. However, the increases in CMR biomarkers were transient, were not associated with LVEF or myocardial strain, and were not useful in identifying traditional CTRCD risk.

Quantitative cardiovascular magnetic resonance findings and clinical risk factors predict cardiovascular outcomes in breast cancer patients

BACKGROUND

Cardiac magnetic resonance (CMR) global longitudinal strain and circumferential strain abnormalities have been associated with left ventricular ejection fraction (LVEF) reduction and cardiotoxicity from oncologic therapy. However, few studies have evaluated the associations of strain and cardiovascular outcomes.

OBJECTIVES

To assess CMR circumferential and global longitudinal strain (GLS) correlations with cardiovascular outcomes including myocardial infarction, systolic dysfunction, diastolic dysfunction, arrhythmias and valvular disease in breast cancer patients treated with and without anthracyclines and/or trastuzumab therapy.

METHODS

Breast cancer patients with a CMR from 2013-2017 at Yale New Haven Hospital were included. Patient co-morbidities, medications, and cardiovascular outcomes were obtained from chart review. Biostatistical analyses, including Pearson correlations, competing risk regression model, and competing risk survival curves comparing the two groups were analyzed.

RESULTS

116 breast cancer with CMRs were included in our analysis to assess differences between Anthracycline/Trastuzumab (AT) (62) treated versus non anthracycline/trastuzumab (NAT) (54) treated patients in terms of imaging characteristics and outcomes. More AT patients 17 (27.4%) developed systolic heart failure compared to the NAT group 6 (10.9%), p = 0.025. Statin use was associated with a significant reduction in future arrhythmias (HR 0.416; 95% CI 0.229-0.755, p = 0.004). In a sub-group of 13 patients that underwent stress CMR, we did not find evidence of microvascular dysfunction by sub-endocardial/sub-epicardial myocardial perfusion index ratio after adjusting for ischemic heart disease.

CONCLUSIONS

In our study, CMR detected signs of subclinical cardiotoxicity such as strain abnormalities despite normal LV function and abnormal circumferential strain was associated with adverse cardiovascular outcomes such as valvular disease and systolic heart failure. Thus, CMR is an important tool during and after cancer treatment to identity and prognosticate cancer treatment-related cardiotoxicity.

Modelling cardiac mechanics in doxorubicin-induced cardiotoxicity following childhood acute lymphoblastic leukemia using a combination of cardiac magnetic resonance imaging, cardiopulmonary exercise testing and the CircAdapt model

Children with acute lymphoblastic leukemia (ALL) are treated with doxorubicin-based chemotherapy that can lead to cardiotoxicity which is a well-known cause of mortality. This study aims to characterize myocardial subtle changes induced by doxorubicin-related cardiotoxicity. We used the combination of cardiac magnetic resonance (CMR) imaging, cardiopulmonary exercise testing and the CircAdapt model to explore hemodynamics and intraventricular mechanisms at rest and during exercise in 53 childhood ALL survivors. A sensitivity analysis of the CircAdapt model identified the most influencing parameters on the left ventricle volume. ANOVA were performed to explore significant differences between left ventricle stiffness, contractility, and arteriovenous pressure drop, as well as survivors' prognostic risk groups. No significant differences were observed between prognostic risk groups. The left ventricle stiffness and left ventricle contractility were non-significantly higher in survivors receiving cardioprotective agents (94.3 %), compared to those at standard and high prognostic risk (77 % and 86 %, respectively). In both left ventricle stiffness and left ventricle contractility, we observed that survivors receiving cardioprotective agents were close to the nominal value of CircAdapt (healthy reference group value is 100 %). This study allowed to improve our knowledge of potential subtle myocardial changes induced by doxorubicin-related cardiotoxicity in childhood ALL survivors. This study confirms that survivors exposed to a high cumulative dose of doxorubicin during treatments are at potential risk of myocardial changes many years after the end of their cancer, while cardio-protective agents may prevent changes in cardiac mechanical properties.

Cardiorespiratory Fitness and Cardiac Magnetic Resonance Imaging in Childhood Acute Lymphoblastic Leukemia Survivors

BACKGROUND

Childhood acute lymphoblastic leukemia survivors' anthracycline-induced cardiotoxicity could be prevented with good cardiorespiratory fitness levels and regular physical activity. This cross-sectional study aimed to assess the association between cardiorespiratory fitness and physical activity with cardiac magnetic resonance parameters.

METHODS

A total of 96 childhood acute lymphoblastic leukemia survivors underwent a maximal cardiopulmonary exercise test and answered physical activity questionnaires. We calculated the odds ratio of the preventive fraction of regular physical activity (≥150 min/wk) and adequate cardiorespiratory fitness levels (above the median ≥31.4 mL·kg-1·min-1) on cardiac magnetic resonance parameters (left ventricular [LV] and right ventricular [RV] morphological and functional parameters).

RESULTS

An adequate cardiorespiratory fitness was associated with a significant preventive fraction for LV (up to 84% for LV end-diastolic volume) and RV volumes (up to 88% for RV end-systolic volume). The adjusted analyses highlighted a preventive fraction of 36% to 91% between an adequate cardiorespiratory fitness and LV and RV parameters, late gadolinium enhancement fibrosis, and cardiac magnetic resonance relaxation times. No associations were reported with regular physical activity.

CONCLUSIONS

This study provides additional evidence regarding the benefits of an adequate cardiorespiratory fitness level for childhood cancer survivors' cardiac health.

Prospective multiparametric CMR characterization and MicroRNA profiling of anthracycline cardiotoxicity: A pilot translational study

Background

Anthracycline cardiotoxicity is a significant clinical challenge. Biomarkers to improve risk stratification and identify early cardiac injury are required.

Objectives

The purpose of this pilot study was to prospectively characterize anthracycline cardiotoxicity using cardiovascular magnetic resonance (CMR), echocardiography and MicroRNAs (MiRNAs), and identify baseline predictors of LVEF recovery.

Methods

Twenty-four patients (age 56 range 18-75 years; 42 % female) with haematological malignancy scheduled to receive anthracycline chemotherapy (median dose 272 mg/m2 doxorubicin equivalent) were recruited and evaluated at three timepoints (baseline, completion of chemotherapy, and 6 months after completion of chemotherapy) with multiparametric 1.5 T CMR, echocardiography and circulating miRNAs sequencing.

Results

Seventeen complete datasets were obtained. CMR left ventricular ejection fraction (LVEF) fell significantly between baseline and completion of chemotherapy (61 ± 3 vs 53 ± 3 %, p < 0.001), before recovering significantly at 6-month follow-up (55 ± 3 %, p = 0.018). Similar results were observed for 3D echocardiography-derived LVEF and CMR-derived longitudinal, circumferential and radial feature-tracking strain. Patients were divided into tertiles according to LVEF recovery (poor recovery, partial recovery, good recovery). CMR-derived mitral annular plane systolic excursion (MAPSE) was significantly different at baseline in patients exhibiting poor LVEF recovery (11.7 ± 1.5 mm) in comparison to partial recovery (13.7 ± 2.7 mm), and good recovery (15.7 ± 3.1 mm; p = 0.028). Furthermore, baseline miRNA-181-5p and miRNA-221-3p expression were significantly higher in this group. T2 mapping increased significantly on completion of chemotherapy compared to baseline (54.0 ± 4.6 to 57.8 ± 4.9 ms, p = 0.001), but was not predictive of LVEF recovery. No changes to LV mass, extracellular volume fraction, T1 mapping or late gadolinium enhancement were observed.

Conclusions

Baseline CMR-derived MAPSE, circulating miRNA-181-5p, and miRNA-221-3p were associated with poor recovery of LVEF 6 months after completion of anthracycline chemotherapy, suggesting their potential predictive role in this context. T2 mapping increased significantly on completion of chemotherapy but was not predictive of LVEF recovery.

Cardiovascular Imaging in Cardio-Oncology: The Role of Echocardiography and Cardiac MRI in Modern Cardio-Oncology

Cardiovascular (CV) events are an increasingly common limitation of effective anticancer therapy. Over the last decade imaging has become essential to patients receiving contemporary cancer therapy. Herein we discuss the current state of CV imaging in cardio-oncology. We also provide a practical apparatus for the use of imaging in everyday cardiovascular care of oncology patients to improve outcomes for those at risk for cardiotoxicity, or with established cardiovascular disease. Finally, we consider future directions in the field given the wave of new anticancer therapies.

Detection of doxorubicin-induced cardiotoxicity using myocardial T1 and T2 relaxation times in childhood acute lymphoblastic leukemia survivors

Doxorubicin leads to dose-dependent cardiotoxicity in childhood acute lymphoblastic leukemia (ALL) survivors. The first aim was to propose a contour-based estimation of T1 and T2 relaxation times based on the myocardial area, while our second aim was to evaluate native T1, post-gadolinium T1 and T2 relaxation time sensitivity to detect myocardial changes. A total of 84 childhood ALL survivors were stratified in regard to their prognostic risk groups: standard risk (SR), n = 20), high-risk with and without dexrazoxane (HR + DEX, n = 39 and HR, n = 25). Survivors' mean age was of 22.0 ± 6.9 years, with a mean age at cancer diagnosis of 8.0 ± 5.2 years. CMR acquisitions were performed on a 3 T MRI system and included an ECG-gated 3(3)3(3)5 MOLLI sequence for T1 mapping and an ECG-gated T2-prepared TrueFISP sequence for T2 mapping. Myocardial contours were semi-automatically segmented using an interactive implementation of cubic Bezier curves. We found excellent repeatability between operators for native T1 (ICC = 0.91), and good repeatability between operators for post-gadolinium T1 (ICC = 0.84) and T2 (ICC = 0.79). Bland and Altman tests demonstrated a strong agreement between our contour-based method and images analyzed using the CVI42 software on the measure of native T1, post-gadolinium T1, and T2. No significant differences between survivors' prognostic risk groups in native T1 were reported, while we observed significant differences between survivors' prognostic risk groups in post-gadolinium T1 and T2. Significant differences were observed between male and female survivors. Differences between groups were also observed in partition coefficients, but no significant differences were observed between male and female survivors. The use of CMR parameters with native T1, post-gadolinium T1, and T2 allowed to show that survivors at a high-risk prognostic were more exposed to doxorubicin-related cardiotoxicity than those who were at a standard risk prognostic or who received dexrazoxane treatments.

When pharmaceutical drugs become environmental pollutants: Potential neural effects and underlying mechanisms

Pharmaceutical drugs have become consumer products, with a daily use for some of them. The volume of production and consumption of drugs is such that they have become environmental pollutants. Their transfer to wastewater through urine, feces or rinsing in case of skin use, associated with partial elimination by wastewater treatment plants generalize pollution in the hydrosphere, including drinking water, sediments, soils, the food chain and plants. Here, we review the potential effects of environmental exposure to three classes of pharmaceutical drugs, i.e. antibiotics, antidepressants and non-steroidal anti-inflammatory drugs, on neurodevelopment. Experimental studies analyzing their underlying modes of action including those related to endocrine disruption, and molecular mechanisms including epigenetic modifications are presented. In addition, the contribution of brain imaging to the assessment of adverse effects of these three classes of pharmaceuticals is approached.

Herceptin-Mediated Cardiotoxicity: Assessment by Cardiovascular Magnetic Resonance

Herceptin (trastuzumab) is a recombinant, humanized, monoclonal antibody that targets the human epidermal growth factor receptor 2 (HER2) and is used in the treatment of HER2-positive breast and gastric cancers. However, it carries a risk of cardiotoxicity, manifesting as left ventricular (LV) systolic dysfunction, conventionally assessed for by transthoracic echocardiography. Clinical surveillance of cardiac function and discontinuation of trastuzumab at an early stage of LV systolic dysfunction allow for the timely initiation of heart failure drug therapies that can result in the rapid recovery of cardiac function in most patients. Often considered the reference standard for the noninvasive assessment of cardiac volume and function, cardiac magnetic resonance (CMR) imaging has superior reproducibility and accuracy compared to other noninvasive imaging modalities. However, due to limited availability, it is not routinely used in the serial assessment of cardiac function in patients receiving trastuzumab. In this article, we review the diagnostic and prognostic role of CMR in trastuzumab-mediated cardiotoxicity.

Cardiotoxicity Associated with Chemotherapy Used in Gastrointestinal Tumours

Cardiotoxicity is a well-recognised side effect of cancer-related therapies with a great impact on outcomes and quality of life in the cancer survivor population. The pathogenesis of chemotherapy-induced cardiotoxicity in patients with gastrointestinal cancers involves various molecular mechanisms, and the combined use of various chemotherapies augments the risk of each drug used alone. In terms of cardiotoxicity diagnosis, novel biomarkers, such as troponins, brain natriuretic peptide (BNP), myeloperoxidases and miRNAs have been recently assessed. Echocardiography is a noninvasive imaging method of choice for the primary assessment of chemotherapy-treated patients to generally evaluate the cardiovascular impact of these drugs. Novel echocardiography techniques, like three-dimensional and stress echocardiography, will improve diagnosis efficacy. Cardiac magnetic resonance (CMR) can evaluate cardiac morphology, function and wall structure. Corroborated data have shown the importance of CMR in the early evaluation of patients with gastrointestinal cancers, treated with anticancer drugs, but further studies are required to improve risk stratification in these patients. In this article, we review some important aspects concerning the cardiotoxicity of antineoplastic drugs used in gastrointestinal cancers. We also discuss the mechanism of cardiotoxicity, the role of biomarkers and the imaging methods used in its detection.

Role of cardiovascular magnetic resonance in early detection and treatment of cardiac dysfunction in oncology patients

The purpose of this review is to provide an overview of the essential role that cardiovascular magnetic resonance (CMR) has in the field of cardio-oncology. Recent findings: CMR has been increasingly used for early identification of cancer therapy related cardiac dysfunction (CTRCD) due to its precision in detecting subtle changes in cardiac function and for myocardial tissue characterization. Summary: CMR is able to identify subclinical CTRCD in patients receiving potentially cardiotoxic chemotherapy and guide initiation of cardio protective therapy. Multiparametric analysis with myocardial strain, tissue characterization play a critical role in understanding important clinical questions in cardio-oncology.

Cardiotoxicity in HER2-positive breast cancer patients

Due to the recent advances in diagnosis and management of patients with HER2-positive breast cancer, especially through novel HER2-targeted agents, cardiotoxicity becomes an emerging problem. Although chemotherapy significantly increases survival, the risk of cardiovascular disease development is high and still underestimated and could imply treatment discontinuation. Frequently, due to lack of rigorous diagnosis strategies, cardiotoxicity assessment is delayed, and, moreover, the efficacy of current therapy options in restoring heart function is questionable. For a comprehensive risk assessment, it is vital to characterize the clinical spectrum of HER2-targeted agents and anthracyclines, as well as their pathogenic pathways involved in cardiotoxicity. Advanced cardiovascular multimodal imaging and circulating biomarkers plays primary roles in early assessing cardiotoxicity and also in guiding specific preventive measures. Even though the knowledge in this field is rapidly expanding, there are still questions that arise regarding the optimal approach in terms of timing and methods. The aim of the current review aims to providean overview of currently available data.

The role of cardiac magnetic resonance imaging in the detection and monitoring of cardiotoxicity in patients with breast cancer after treatment: a comprehensive review

The use of chemotherapy medicines for breast cancer (BC) has been associated with an increased risk of cardiotoxicity. In recent years, there have been growing interests regarding the application of cardiovascular magnetic resonance (CMR) imaging, a safe and noninvasive modality, with the potential to identify subtle morphological and functional changes in the myocardium. In this investigation, we aimed to review the performance of various CMR methods in diagnosing cardiotoxicity in BC, induced by chemotherapy or radiotherapy. For this purpose, we reviewed the literature available in PubMed, MEDLINE, Cochrane, Google Scholar, and Scopus databases. Our literature review showed that CMR is a valuable modality for identifying and predicting subclinical cardiotoxicity induced by chemotherapy. The novel T1, T2, and extracellular volume mapping techniques may provide critical information about cardiotoxicity, in addition to other CMR features such as functional and structural changes. However, further research is needed to verify the exact role of these methods in identifying cardiotoxicity and patient management. Since multiple studies have reported the improvement of left ventricular performance following the termination of chemotherapy regimens, CMR remains an essential imaging tool for the prediction of cardiotoxicity and, consequently, decreases the mortality rate of BC due to heart failure.

Cardiovascular Magnetic Resonance Imaging: Identifying the Effects of Cancer Therapy

The era of modern oncology incorporates an ever-evolving personalized approach to hematological malignancies and solid tumors. As a result, patient survival rates have, in part, substantially improved, depending on the specific type of underlying malignancy. However, systemic therapies may come along with potential cardiotoxic effects resulting in heart failure with increased morbidity and mortality. Ultimately, patients may survive their malignancy but die as a result of cancer treatment. Cardiovascular magnetic resonance imaging has long been in use for the assessment of function and tissue characteristics in patients with various nonischemic cardiac diseases. Besides an introductory overview on the general definition of cardiotoxicity including potential underlying mechanisms, this review provides insight into the application of various cardiovascular magnetic resonance imaging techniques in the setting of cancer therapy-related cardiac and vascular toxicity. Early identification of cardiotoxic effects may allow for on-time therapy adjustment and/or cardioprotective measures to avoid subsequent long-term heart failure with increased mortality.

Magnetic Resonance Imaging to Detect Cardiovascular Effects of Cancer Therapy: JACC CardioOncology State-of-the-Art Review

This paper aims to empower and inform cardio-oncologists by providing a practical guide to the clinical application of cardiac magnetic resonance (CMR) in the rapidly evolving field of cardio-oncology. Specifically, we describe how CMR can be used to assess the cardiovascular effects of cancer therapy. The CMR literature, relevant societal guidelines, indication-specific imaging protocols, and methods to overcome some of the challenges encountered in performing and accessing CMR are reviewed.

The use of cardiovascular magnetic resonance as an early non-invasive biomarker for cardiotoxicity in cardio-oncology

Contemporary cancer therapy has resulted in significant survival gains for patients. However, many current and emerging cancer therapies have an associated risk of cardiotoxicity, either acutely or later in life. Regular cardiac screening and surveillance is recommended for patients undergoing treatment for cancer, with emphasis on the early detection of cardiotoxicity before irreversible complications develop. Cardiovascular magnetic resonance imaging is able to accurately assess cardiac structure, function, and perform advanced myocardial tissue characterisation, including perfusion, features which may facilitate the diagnosis and management of cardiotoxicity in cancer survivors. This review outlines the current standards for the diagnosis and screening of cardiotoxicity, with particular focus on current and future applications of cardiovascular magnetic resonance imaging.

Cardio-oncology, the myth of Sisyphus, and cardiovascular disease in breast cancer survivors

The number of breast cancer (BC) survivors has been increasing lately, due to the improvement in early detection strategies and oncological treatments. However, BC survivors are 3 times as likely to develop heart failure (HF) within 5 years of cancer diagnosis, and 7/100 of them will develop HF in a median follow-up of 8.5 years. Furthermore, HF in BC survivors has a worse prognosis compared to other causes of HF. Anthracyclines and trastuzumab have been proven to improve survival. However, they are also considered as the main causative factors of HF in BC survivors. Old patients, those with a pre-existing cardiovascular (CV) risk factors/disease, prior exposure to chemotherapy and radiotherapy are at increased risk. Serial evaluation of troponins and cardiac imaging parameters using echocardiography and cardiovascular magnetic resonance can significantly contribute to the early diagnosis of cardiac involvement before overt HF will develop. Assessment and immediate treatment of traditional CV risk factors is the first step for cardiotoxicity prevention. In BC survivors with known heart disease, the clinical stabilization is strongly recommended for cardiotoxicity prevention. Finally, in high-risk CV patients, primary prevention including cardioprotectants and/or CV drugs should be applied. According to recent studies, the early start of ACE inhibitors and β-blockers and the modification of anti-cancer treatment can prevent the decline in left ventricular ejection fraction. However, further multicenter studies are needed to establish both prevention and treatment protocols to successfully overcome HF development in BC survivors.

Measurement of Ejection Fraction by Cardiac Magnetic Resonance Imaging and Echocardiography to Monitor Doxorubicin-Induced Cardiotoxicity

Doxorubicin is a standard treatment option for breast cancer, lymphoma, and leukemia, but its benefits are limited by its potential for cardiotoxicity. The primary objective of this study was to compare cardiac magnetic resonance imaging (CMRI) versus echocardiography (ECHO) to detect a reduction in left ventricular ejection function, suggestive of doxorubicin cardiotoxicity. We studied eligible patients who were 18 years or older, who had breast cancer or lymphoma, and who were offered treatment with doxorubicin with curative intent dosing of 240 to 300 mg/m ² body surface area between March 1, 2009 and October 31, 2013. Patients underwent baseline CMRI and ECHO. Both imaging studies were repeated after four cycles of treatment. Ejection fraction (EF) calculated by both methods was compared and analyzed with the inferential statistical Student's t test. Twenty-eight eligible patients were enrolled. Two patients stopped participating in the study before undergoing baseline CMRI; 26 patients underwent baseline ECHO and CMRI. Eight of those 26 patients declined posttreatment studies, so the final study population was 18 patients. There was a significant difference in EF pre- and posttreatment in the CMRI group ( p  = 0.009) versus the ECHO group that showed no significant differences in EF ( p  = NS). It appears that CMRI is superior to ECHO for detecting doxorubicin-induced reductions in cardiac systolic function. However, ECHO is less expensive and more convenient for patients because of its noninvasive character and bedside practicality. A larger study is needed to confirm these findings.

MRI of Cardiotoxicity

Cardiovascular magnetic resonance (CMR) imaging is useful to identify systolic dysfunction, particularly when echocardiographic imaging is not acceptable because of poor acoustic windows or when left ventricular ejection fraction (LVEF) is inconclusive by other modalities and an accurate LVEF measurement is needed. Of particular advantage in cardio-oncology is CMR's capability to perform tissue characterization to noninvasively identify changes in pathologic conditions related to cancer therapy or to discriminate causes of disease that may confound presentation in cardio-oncology patients. For these reasons, there is an increasing use of CMR in the screening and surveillance of cardio-oncology patients.

MRI in cardio-oncology: A review of cardiac complications in oncologic care

From detailed characterization of cardiac abnormalities to the assessment of cancer treatment-related cardiac dysfunction, cardiac MRI is playing a growing role in the evaluation of cardiac pathology in oncology patients. Current guidelines are now incorporating the use of MRI for the comprehensive multidisciplinary approach to cancer management, and innovative applications of MRI in research are expanding its potential to provide a powerful noninvasive tool in the arsenal against cancer. This review focuses on the application of cardiac MRI to diagnose and manage cardiovascular complications related to cancer and its treatment. Following an introduction to current cardiac MRI methods and principles, this review is divided into two sections: functional cardiovascular analysis and anatomical or tissue characterization related to cancer and cancer therapeutics. Level of Evidence: 5 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;50:1349-1366.

Assessment of Cardiotoxicity of Cancer Chemotherapy: The Value of Cardiac MR Imaging

Chemotherapy is associated with cardiovascular injury, including the development of a cardiomyopathy and vascular remodeling. Cardiac magnetic resonance (CMR) is sensitive to detect not only established morphologic and functional abnormalities but also early, potentially reversible, signs of myocardial injury. It robustly detects and quantifies myocardial edema, inflammation, and focal fibrosis, as well as interstitial fibrosis and vascular remodeling. These capabilities support the role of CMR as an excellent tool for evaluating cardiotoxicity. Novel CMR markers may even enhance patient management by facilitating the early detection of reversible myocardial tissue remodeling before classic morphologic and functional changes appear.

Doxorubicin-Induced Cardiomyopathy in Children

Doxorubicin-induced cardiotoxicity in childhood cancer survivors is a growing problem. The population of patients at risk for cardiovascular disease is steadily increasing, as five-year survival rates for all types of childhood cancers continue to improve. Doxorubicin affects the developing heart differently from the adult heart and in a subset of exposed patients, childhood exposure leads to late, irreversible cardiomyopathy. Notably, the prevalence of late-onset toxicity is increasing in parallel with improved survival. By the year 2020, it is estimated that there will be 500,000 childhood cancer survivors and over 50,000 of them will suffer from doxorubicin-induced cardiotoxicity. The majority of the research to-date, concentrated on childhood cancer survivors, has focused mostly on clinical outcomes through well-designed epidemiological and retrospective cohort studies. Preclinical studies have elucidated many of the cellular mechanisms that elicit acute toxicity in cardiomyocytes. However, more research is needed in the areas of early- and late-onset cardiotoxicity and more importantly improving the scientific understanding of how other cells present in the cardiac milieu are impacted by doxorubicin exposure. The overall goal of this review is to succinctly summarize the major clinical and preclinical studies focused on doxorubicin-induced cardiotoxicity. As the prevalence of patients affected by doxorubicin exposure continues to increase, it is imperative that the major gaps in existing research are identified and subsequently utilized to develop appropriate research priorities for the coming years. Well-designed preclinical research models will enhance our understanding of the pathophysiology of doxorubicin-induced cardiotoxicity and directly lead to better diagnosis, treatment, and prevention. © 2019 American Physiological Society. Compr Physiol 9:905-931, 2019.

Pretransplant Cardiac Evaluation Using Novel Technology

Hematopoietic stem-cell transplantation (HSCT) is a complex procedure that has been increasingly successful in treating malignant and nonmalignant conditions. Despite its effectiveness, it can be associated with potentially life-threatening adverse effects. New onset heart failure, ischemic disease, and arrhythmias are among the most notable cardiovascular complications post-HSCT. As a result, appropriate cardiac risk stratification prior to transplant could result in decreased morbidity and mortality by identifying patients with a higher probability of tolerating possible toxicities associated with HSCT. In this review, we aim to discuss the utility of cardiac screening using novel modalities of imaging technology in the pre-HSCT phase.

Heart failure following oncological treatment

PURPOSE OF REVIEW

The aim of this review is to give the reader an up-to-date overview of the progress made in the burgeoning field of cardio-oncology, encompassing oncological treatments conferring risk, prediction strategies to identify patients at risk, imaging and biomarker monitoring for emergent or subclinical toxicity and prevention in primary and secondary settings with a focus on heart failure.

RECENT FINDINGS

The rapid recent advances in cancer management, particularly with the expansion of targeted and immunotherapies, have led to substantial improvements in outcome, but have also added to the potential causes of cardiac toxicity, which can lead to heart failure. Against this, there has been progression in the field of imaging for cardiac toxicity, identification of at-risk individuals and the clarification of the role of therapy for prevention and treatment of cardiac toxicity.

SUMMARY

The findings described in this review provide guidance to clinicians in order to direct monitoring strategy and therapy choice, both in the individual with preexisting cardiac comorbidities and in those predicted to be at the highest risk of cardiac toxicity wherever therapy elements carrying cardiac risk are considered oncologically appropriate.

Long term cardiovascular magnetic resonance phenotyping of anthracycline cardiomyopathy

BACKGROUND

Anthracycline cardiomyopathy contributes to the morbidity and mortality of cancer survivors but long-term data are lacking. This study sought to describe the phenotype of long-term anthracycline cardiomyopathy, the prevalence of myocardial fibrosis and its association with cardiac remodeling, systolic function and clinical outcomes.

METHODS AND RESULTS

We undertook contrast-enhanced CMR in 81 cancer survivors at median 5 years after anthracycline (mean dose 279 SD 89 mg/m²). Participants were aged 55 SD 14 years; 68% were female. Mean LVEF was impaired (49 SD 12%), driven by a pathological increase in iLVESV (47 SD 23 ml/m²). 19% of participants exhibited LGE, which was associated with significant adverse left ventricular remodeling and reduced systolic function (iLVEDV: 102 SD 34 vs 83 SD 21 ml/m², p = 0.03; iLVESV 61 SD 32 vs 43 SD 20 ml/m², p = 0.03; LVEF: 43 SD 11 vs 50 SD 12%, p = 0.03). In subgroup analysis of 36 patients, 36% had elevated native T1 measurements, which was associated with significant adverse left ventricular remodeling (iLVEDV: 97 SD 22 vs 74 SD 19 ml/m², p = 0.002; iLVESV: 56 SD 22 vs 35 SD 15 ml/m², p = 0.005), reduced systolic function (LVEF 44 SD 13 vs 55 SD 9%, p = 0.01), and hospitalizations for heart failure (38% vs 9%, p = 0.03). Absolute native T1 measurements correlated significantly with iLVEDV (p ≤ 0.001, R² 0.33), iLVESV (p < 0.001, R² 0.36), LVEF (p < 0.001, R² 0.35), LAVi (p = 0.04, R² 0.12) and MAPSE (p = 0.02, R² 0.14).

CONCLUSIONS

Long-term anthracycline cardiomyopathy is characterized by pathologically increased iLVESV. Both LGE and elevated native T1 measurements were associated with significant adverse cardiac remodeling and reduced systolic function, and the latter with heart failure hospitalizations.

Cardiovascular Evaluation of Children With Malignancies

PURPOSE OF REVIEW

The anthracycline (AC) group of drugs is widely used for cancer chemotherapy and has improved outcomes in many childhood malignancies. However, cardiovascular complications are major causes of morbidity and mortality in AC recipients, with the greatest risk factor being a higher cumulative dosage. The purpose of this review is to describe the etio-pathogenesis and risk factors of AC induced cardiotoxicity, with emphasis on currently available and emerging modalities of non-invasive imaging in its surveillance, and to review guidelines on its prevention and treatment.

RECENT FINDINGS

Presently, ejection fraction and shortening fraction derived from two-dimensional echocardiography are the most widely used parameter for monitoring of cardiac function in childhood cancer survivors. The newer speckle tracking echocardiography has shown potential to detect abnormalities in ventricular function prior to the conventional measures such as ejection fraction and shortening fraction. When available, three-dimensional echocardiography should be used as it allows for more accurate estimation of ejection fraction. Newer magnetic resonance imaging (MRI) techniques, such as delayed enhancement and T1 mapping, are useful adjuncts for cardiac evaluation in cancer survivors, especially in patients with poor echocardiographic windows. Early detection and management of cardiovascular diseases is one of the major goals in the long-term follow-up of childhood cancer survivors. In addition to conventional two-dimensional echocardiography, newer techniques such as speckle tracking echocardiography and three-dimensional echocardiography should be incorporated due to its ability to detect early changes in anthracycline-induced cardiotoxicity. However further research are needed to guide changes in management due to abnormalities in speckle tracking echocardiography.

Cardiovascular imaging in cardio-oncology

Cancer therapy may lead to cardiovascular complications and can promote each aspect of cardiac disease manifestation, such as vascular disease including coronary heart disease, myocardial diseases including heart failure, structural heart diseases including valvular heart diseases, and rhythm disorders. All potential complications of cancer therapy onto the cardiovascular system require imaging for diagnostic workup as well as monitoring of therapy. Transthoracic echocardiography (TTE) is the most frequently used tool for assessment of cardiac function during or after cancer therapy in daily clinical routine. With modern techniques like strain analysis, echocardiography allows to detect a variety of cardiac diseases as caused by cancer therapy even at subclinical stages. For further workup, specific imaging techniques including nuclear imaging are needed in a multimodality imaging approach to in detail characterize the underlying pathophysiology and to improve the management of the patients. Therefore, the field of imaging in cardio-oncology is rapidly growing. This review article will give an overview about existing literature regarding the role of imaging in the diagnostic evaluation and management of therapy in patient with prior or ongoing cancer therapy.

Early diagnosis of cardiotoxic complications of chemotherapy: the possibility of radiation research methods

Oncological diseases are the main causes of death in the world. Modern treatment of cancer patients contributes to an increase in survival rate due to strong chemotherapeutic drugs, the use of which is accompanied by toxic effects on cardiomyocytes. The main manifestations of cardiotoxicity are left ventricular dysfunction, myocardial ischemia, thromboembolic complications, chronic heart failure. As a result, the risk of cardiovascular mortality may be higher than the risk of death from the tumor process. An important task of oncologists and cardiologists is the early diagnosis of cardiotoxic complications in order to start treatment in time and reduce mortality from cardiovascular pathology in cancer patients.

Methods of diagnosis in cardio-oncology

Early diagnosis and advances in treatment have led to improved survival of patients with cancer, but have also increased morbidity and mortality due to treatment side effects. Cardiovascular diseases (CVDs) are one of the most frequent of these side effects. As a result of the direct effects of radiation therapy and chemotherapy on heart and vessels сan be: acceleration of atherosclerosis, damage of cardiomyocytes and endothelium, and arterial and venous thrombosis. The direct effect of the cancer treatment on the heart is called cardiotoxicity. Early diagnosis and identification of patients at high risk of cardiotoxicity is the first step towards successful prevention of CVD in cancer patients without compromising cancer care, which ultimately leads to a reduction in mortality. Echocardiography is the method of choice for the detection of myocardial dysfunction during and after cancer therapy. New methods of imaging like three-dimensional echocardiography, speckle-tracking echocardiography, cardiac magnetic resonance show a higher sensitivity in detecting of early myocardial dysfunction during cancer therapy. This review outlines the main diagnostic algorithms and approaches used in cardiooncology.

The Role of Cardiovascular Magnetic Resonance for Surveillance of Cardiac Performance upon Receipt of Potentially Cardiotoxic Cancer Therapeutics

PURPOSE OF REVIEW

Advancements in cancer treatment have resulted in improved cancer-related survival and consequently an increase in the number of cancer survivors. Unfortunately, associated with this increase in cancer-related survivorship, cardiac events have occurred with increasing frequency in cancer survivors. Recognition that cancer survivors are at increased risk for cardiovascular (CV) morbidity has generated interest to develop cardiac imaging techniques that identify subclinical CV disease during receipt of potentially cardiotoxic cancer treatment. Since subclinical cardiovascular disease precedes future cardiac events, early recognition of subclinical CV disease during receipt of potentially cardiotoxic cancer treatment offers the opportunity to initiate strategies that prevent further evolution of subclinical CV disease as well as cardiac events.

RECENT FINDINGS

Cardiovascular magnetic resonance imaging (CMR) is an advanced imaging technique that identifies imaging markers of subclinical cardiovascular disease in patients receiving potentially cardiotoxic cancer treatment regimens. In this article, we review the use of CMR for identifying subclinical cardiac disease in patients receiving potentially cardiotoxic cancer treatment regimens. The ability of contemporary CMR to accurately define cardiac anatomy, function, and tissue characteristics may represent a critical tool to assess patients with cancer.

Cardiovascular disease in survivors of childhood cancer

PURPOSE OF REVIEW

We review the cardiotoxic chemotherapeutic agents, the clinical and subclinical presentations and progression of their cardiotoxicity, and the management of the subsequent cardiovascular disease in survivors of childhood cancer. We discuss various preventive measures, especially the cardioprotectant, dexrazoxane, whose use with anthracycline chemotherapy, including doxorubicin, is based on strong evidence. Most treatment recommendations for this unique population are based on expert opinion, not on empirical evidence.

RECENT FINDINGS

As patients with childhood cancers live longer, morbidity from the cardiac side effects of chemotherapy is increasing. Treatment-related cardiac damage is irreversible and often progressive. It is imperative that such damage be prevented with strategies such as limiting the cumulative anthracycline dose, the use of anthracycline structural analogues and the use of cardioprotective agents.

SUMMARY

A deeper understanding of the mechanisms of their cardiotoxicity reveals that there is no 'safe' dose of anthracyclines. However, certain risk factors, such as higher lifetime anthracycline cumulative doses, higher anthracycline dose rates, female sex, longer follow-up, younger age at anthracycline treatment and cardiac irradiation, are associated with more severe cardiotoxicity. We advocate the use of dexrazoxane to limit the cardiotoxic effects of anthracycline chemotherapy.

Cardiovascular Magnetic Resonance in the Oncology Patient

Patients with or receiving potentially cardiotoxic treatment for cancer are susceptible to developing decrements in left ventricular mass, diastolic function, or systolic function. They may also experience valvular heart disease, pericardial disease, or intracardiac masses. Cardiovascular magnetic resonance may be used to assess cardiac anatomy, structure, and function and to characterize myocardial tissue. This combination of features facilitates the diagnosis and management of disease processes in patients with or those who have survived cancer. This report outlines and describes prior research involving cardiovascular magnetic resonance for assessing cardiovascular disease in patients with or previously having received treatment for cancer.

Native myocardial T1 time can predict development of subsequent anthracycline-induced cardiomyopathy

Aims

This study aims to assess subclinical changes in functional and morphological myocardial magnetic resonance parameters very early into an anthracycline treatment, which may predict subsequent development of anthracycline‐induced cardiomyopathy (aCMP).

Methods and results

Thirty sarcoma patients with planned anthracycline‐based chemotherapy (360–400 mg/m² doxorubicin‐equivalent) were recruited. Median treatment time was 19.1 ± 2.1 weeks. Enrolled individuals received three cardiovascular magnetic resonance studies (before treatment, 48 h after first anthracycline treatment, and upon completion of treatment). Native T1 mapping (modified Look–Locker inversion recovery 5s(3s)3s), T2 mapping, and extracellular volume maps were acquired in addition to a conventional cardiovascular magnetic resonance with steady‐state free precession cine imaging at 1.5 T. Patients were given 0.2 mmol/kg gadoteridol for extracellular volume quantification and late gadolinium enhancement imaging. Development of relevant aCMP was defined as drop of left ventricular ejection fraction (LVEF) by >10%. For analysis, 23 complete data sets were available. Nine patients developed aCMP with LVEF reduction >10% until end of chemotherapy. Baseline LVEF was not different between patients with and without subsequent aCMP. When assessed 48 h after first dose of antracyclines, patients with subsequent aCMP had significantly lower native myocardial T1 times compared with before therapy (1002.0 ± 37.9 vs. 956.5 ± 29.2 ms, P < 0.01) than patients who did not develop aCMP (990.9 ± 56.4 vs. 978.4 ± 57.4 ms, P > 0.05). Patients with aCMP had decreased left ventricular mass upon completion of therapy (86.9 ± 24.5 vs. 81.1 ± 22.3 g; P = 0.02), while patients without aCMP did not show a change in left ventricular mass (81.8 ± 21.0 vs. 79.2 ± 18.1 g; P > 0.05). No patient developed new myocardial scars or compact myocardial fibrosis under chemotherapy.

Conclusions

Early decrease of T1 times 48 h after first treatment with anthracyclines can predict the development of subsequent aCMP after completion of chemotherapy.

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.

A recommended practical approach to the management of anthracycline-based chemotherapy cardiotoxicity: an opinion paper of the working group on drug cardiotoxicity and cardioprotection, Italian Society of Cardiology

Anthracyclines are the mainstay of treatment of a variety of haematological malignancies and solid tumours. Unfortunately, the clinical use of these drugs is limited by cumulative, dose-related cardiotoxicity which may ultimately lead to a severe and irreversible form of cardiomyopathy. Thus, there is an increasing need for close cooperation among cardiologists, oncologists and haemato-oncologists. As anthracyclines save lives, the logical goal of this cooperation, besides preventing or mitigating cardiotoxicity, is to promote an acceptable balance between the potential cardiac side effects and the vital benefit of anticancer treatment. This manuscript, which is specifically addressed to the cardiologist who has not accumulated much experience in the field of cancer therapy, focuses on several topics, that is old and new mechanisms of cardiac toxicity, late cardiac toxicity, the importance of overall risk assessment, the key role of a cardiology consult before starting cancer therapy, and the pros and cons of primary and secondary prevention programmes.

Cardiac Magnetic Resonance Imaging in Oncology

BACKGROUND

Cardiac magnetic resonance imaging (MRI) is emerging as an important diagnostic modality in the management of cardiovascular-related dysfunction in oncological diseases. Advances in imaging techniques have enhanced the detection and evaluation of cardiac masses; meanwhile, innovative applications have created a growing role for cardiac MRI for the management of cardiotoxicity caused by cancer therapies.

METHODS

An overview is provided of the clinical indications and technical considerations of cardiac MRI. Its role in the evaluation of cardiac masses and cardiac function is reviewed, and novel sequences are discussed that are giving rise to future directions in cardio-oncology research. A review of the literature was also performed, focusing on cardiac MRI findings associated with cardiac dysfunction related to cancer treatment.

RESULTS

Cardiac MRI can be used to differentiate benign and malignant primary cardiac tumors, metastatic disease, and pseudotumors with high spatial and temporal resolution. Cardiac MRI can also be used to detect the early and long-term effects of cardiotoxicity related to cancer therapy. This is accomplished through a multiparametric approach that uses conventional bright blood, dark blood, and postcontrast sequences while also considering the applicability of newer T1 and T2 mapping sequences and other emerging techniques.

CONCLUSIONS

Cardio-oncology programs have an expanding presence in the multidisciplinary approach of cancer care. Consequently, knowledge of cardiac MRI and its potential applications is critical to the success of contemporary cancer diagnostics and cancer management.

Cardiotoxicity and cardiomyopathy in children and young adult survivors of hematopoietic stem cell transplant

Cardiomyopathy is common in long-term survivors of pediatric hematopoietic stem cell transplant (HSCT). Events occurring before and after HSCT when combined with specific insults during HSCT likely contribute to long-term risk. Strategies for detecting subclinical cardiomyopathy prior to patients developing overt heart failure are under investigation. Changes in HSCT preparative regimens and cardioprotective medications administered during chemotherapy may alter the risk for cardiomyopathy. Interventions in long-term survivors such as lifestyle modification and cardioactive medications are of increasing importance. Herein we review the causes of cardiac injury, discuss strategies for detection of cardiomyopathy, and evaluate therapeutic options for long-term HSCT survivors.

Update on the Role of Cardiac Magnetic Resonance in Acquired Nonischemic Cardiomyopathies

Cardiomyopathies refer to a variety of myocardial disorders without underlying coronary artery disease, valvular heart disease, hypertension, or congenital heart disease. Several imaging modalities are available, but cardiac magnetic resonance (CMR) has now established itself as a crucial imaging technique in the evaluation of several cardiomyopathies. It not only provides comprehensive information on structure and function, but also can perform tissue characterization, which helps in establishing the etiology of cardiomyopathy. CMR is also useful in establishing the diagnosis, providing guidance for endomyocardial biopsy, accurate quantification of function, volumes, and fibrosis, prognostic determination, risk stratification, and monitoring response to therapy. In this article, we review the current role of CMR in the evaluation of several acquired nonischemic cardiomyopathies, particularly focusing on recent advances in knowledge. We also discuss in detail a select group of common acquired nonischemic cardiomyopathies.

Characterization of the Changes in Cardiac Structure and Function in Mice Treated With Anthracyclines Using Serial Cardiac Magnetic Resonance Imaging

BACKGROUND

Anthracyclines are cardiotoxic; however, there are limited data characterizing the serial changes in cardiac structure and function after anthracyclines. The aim of this study was to use cardiac magnetic resonance to characterize anthracycline-induced cardiotoxicity in mice.

METHODS AND RESULTS

This was a longitudinal cardiac magnetic resonance and histological study of 45 wild-type male mice randomized to doxorubicin (n=30, 5 mg/kg of doxorubicin/week for 5 weeks) or placebo (n=15). A cardiac magnetic resonance was performed at baseline and at 5, 10, and 20 weeks after randomization. Measures of primary interest included left ventricular ejection fraction, myocardial edema (multiecho short-axis spin-echo acquisition), and myocardial fibrosis (Look-Locker gradient echo). In doxorubicin-treated mice versus placebo, there was an increase in myocardial edema at 5 weeks (T2 values of 32±4 versus 21±3 ms; P<0.05), followed by a reduction in left ventricular ejection fraction (54±6 versus 63±5%; P<0.05) and an increase in myocardial fibrosis (extracellular volume of 0.34±0.03 versus 0.27±0.03; P<0.05) at 10 weeks. There was a strong association between the early (5 weeks) increase in edema and the subacute (10 weeks) increase in fibrosis (r=0.90; P<0.001). Both the increase in edema and fibrosis predicted the late doxorubicin-induced mortality in mice (P<0.001).

CONCLUSIONS

Our data suggest that, in mice, anthracycline-induced cardiotoxicity is associated with an early increase in cardiac edema and a subsequent increase in myocardial fibrosis. The early increase in edema and subacute increase in fibrosis are strongly linked and are both predictive of late mortality.

Role of Imaging in Cardio-Oncology

OPINION STATEMENT

Recent advances in cancer treatment and research have greatly improved survival rates for patients with cancer. However, many of these cancer survivors are developing cardiac disease-most commonly heart failure as a result of this treatment. Certain chemotherapeutic agents, including anthracyclines and trastuzumab, have been linked to cardiotoxicity-induced cardiomyopathy in cancer patients. It has been reported as early as during infusion and as late as several years following treatment. Radiation therapy, particularly to the left breast, has also been linked to cardiac disease. The responsibility of cardiac monitoring has traditionally fallen on oncologists using assessment of LVEF through multigated acquisition (MUGA) scans or echocardiograms. The "formal" definition of cardiotoxicity, as a 5 to 10% decrease in LVEF from its baseline, even though not validated, is currently used by clinicians to alter treatment, but it has been recently challenged, as a possible irreversible late stage of a myocardial insult. Furthermore, it falls into the interobserver variability range of echocardiography. The growing field of medicine called cardio-oncology is based on emerging research that has shown that more advanced imaging modalities can help detect cardiotoxicity early, allowing the patient to receive treatment and avoid developing heart failure from cancer treatment. While traditional imaging still has its place in cardiac monitoring, cardiac magnetic resonance imaging is the most accurate and detailed imaging modality available to assess cardiotoxicity. Our own pilot cardiac MRI study suggests that a normal left ventricular remodeling to chemotherapy, when patients have not developed heart failure symptoms, could occur over time. Perhaps, knowing a baseline normal response could help us to define a more accurate definition of cardiotoxicity by CMR. Here, we discuss various imaging modalities and emerging techniques that can assist in detecting early signs of cardiotoxicity and thus reduce the incidence of cardiac disease in cancer survivors.

Cardiovascular imaging in the diagnosis and monitoring of cardiotoxicity: cardiovascular magnetic resonance and nuclear cardiology

Chemotherapy-induced cardiotoxicity (CTX) is a determining factor for the quality of life and mortality of patients administered potentially cardiotoxic drugs and in long-term cancer survivors. Therefore, prevention and early detection of CTX are highly desirable, as is the exploration of alternative therapeutic strategies and/or the proposal of potentially cardioprotective treatments. In recent years, cardiovascular imaging has acquired a pivotal role in this setting. Although echocardiography remains the diagnostic method most used to monitor cancer patients, the need for more reliable, reproducible and accurate detection of early chemotherapy-induced CTX has encouraged the introduction of second-line advanced imaging modalities, such as cardiac magnetic resonance (CMR) and nuclear techniques, into the clinical setting. This review of the Working Group on Drug Cardiotoxicity and Cardioprotection of the Italian Society of Cardiology aims to afford an overview of the most important findings from the literature about the role of CMR and nuclear techniques in the management of chemotherapy-treated patients, describe conventional and new parameters for detecting CTX from both diagnostic and prognostic perspectives and provide integrated insight into the role of CMR and nuclear techniques compared with other imaging tools and versus the positions of the most important international societies.