Rationale and design of the Children's Oncology Group (COG) study ALTE1621: a randomized, placebo-controlled trial to determine if low-dose carvedilol can prevent anthracycline-related left ventricular remodeling in childhood cancer survivors at high risk for developing heart failure

Effect of carvedilol versus placebo on cardiac function in anthracycline-exposed survivors of childhood cancer (PREVENT-HF): a randomised, controlled, phase 2b trial

BACKGROUND

Carvedilol improves cardiac function in patients with heart failure but remains untested as cardioprotective therapy in long-term childhood cancer survivors (ie, those who have completed treatment for childhood cancer and are in remission) at risk for heart failure due to high-dose anthracycline exposure. We aimed to evaluate the activity and safety of low-dose carvedilol for heart failure risk reduction in childhood cancer survivors at highest risk for heart failure.

METHODS

PREVENT-HF was a randomised, double-blind, phase 2b trial done at 30 hospitals in the USA and Canada. Patients were eligible if they had any cancer diagnosis that resulted in at least 250 mg/m2 cumulative exposure to anthracycline by age 21 years; completed their cancer treatment at least 2 years previously; an ejection fraction of at least 50% or fractional shortening of at least 25%, or both; and bodyweight of at least 40 kg. Patients were randomly assigned (1:1) with automated computer-generated permuted block randomisation (block size of 4), stratified by age at diagnosis, time since diagnosis, and history of chest-directed radiotherapy, to carvedilol (up-titrated from 3·125 g per day to 12·5 mg per day) or placebo orally for 2 years. Participants, staff, and investigators were masked to study group allocation. The primary endpoint was to establish the effect of carvedilol on standardised left ventricular wall thickness-dimension ratio Z score (LVWT/Dz). Treatment effects were analysed with a linear mixed-effects model for normally distributed data with a linear time effect and testing the significance of treatment*time interaction in the modified intention-to-treat (mITT) cohort (ie, all randomly assigned participants who had a baseline and at least one subsequent echocardiogram measurement). Safety was assessed in the ITT population (ie, all randomly assigned participants). This trial was registered with ClinicalTrials.gov, NCT027175073, and enrolment and follow-up are complete.

FINDINGS

Between July 3, 2012, and June 22, 2020, 196 participants were enrolled, of whom 182 (93%) were eligible and randomly assigned to either carvedilol (n=89) or placebo (n=93; ITT population). Median age was 24·7 years (IQR 19·6-36·6), 91 (50%) participants were female, 91 (50%) were male, and 119 (65%) were non-Hispanic White. As of data cutoff (June 10, 2022), median follow-up was 725 days (IQR 378-730). 151 (n=75 in the carvedilol group and n=76 in the placebo group) of 182 participants were included in the mITT population, among whom LVWT/Dz was similar between the two groups (-0·14 [95% CI -0·43 to 0·16] in the carvedilol group vs -0·45 [-0·77 to -0·13] in the placebo group; difference 0·31 [95% CI -0·10 to 0·73]; p=0·14). Two (2%) of 89 patients in the carvedilol group two adverse events of grade 2 or higher (n=1 shortness of breath and n=1 arthralgia) and none in the placebo group. There were no adverse events of grade 3 or higher and no deaths.

INTERPRETATION

Low-dose carvedilol appears to be safe in long-term childhood cancer survivors at risk for heart failure, but did not result in significant improvement of LVWT/Dz compared with placebo. These results do not support the use of carvedilol for secondary heart failure prevention in anthracycline-exposed childhood cancer survivors.

FUNDING

National Cancer Institute, Leukemia & Lymphoma Society, St Baldrick's Foundation, Altschul Foundation, Rally Foundation, American Lebanese Syrian Associated Charities.

Pharmacotherapy for Cancer Treatment-Related Cardiac Dysfunction and Heart Failure in Childhood Cancer Survivors

The number of childhood cancer survivors is increasing rapidly. According to American Association for Cancer Research, there are more than 750,000 childhood cancer survivors in the United States and Europe. As the number of childhood cancer survivors increases, so does cancer treatment-related cardiac dysfunction (CTRCD), leading to heart failure (HF). It has been reported that childhood cancer survivors who received anthracyclines are 15 times more likely to have late cancer treatment-related HF and have a 5-fold higher risk of death from cardiovascular (CV) disease than the general population. CV disease is the leading cause of death in childhood cancer survivors. The increasing need to manage cancer survivor patients has led to the rapid creation and adaptation of cardio-oncology. Cardio-oncology is a multidisciplinary science that monitors, treats, and prevents CTRCD. Many guidelines and position statements have been published to help diagnose and manage CTRCD, including those from the American Society of Clinical Oncology, the European Society of Cardiology, the Canadian Cardiovascular Society, the European Society of Medical Oncology, the International Late Effects of Childhood Cancer Guideline Harmonization Group, and many others. However, there remains a gap in identifying high-risk patients likely to develop cardiomyopathy and HF in later life, thus reducing primary and secondary measures being instituted, and when to start treatment when there is echocardiographic evidence of left ventricular (LV) dysfunctions without symptoms of HF. There are no randomized controlled clinical trials for treatment for CTRCD leading to HF in childhood cancer survivors. The treatment of HF due to cancer treatment is similar to the guidelines for general HF. This review describes the latest pharmacologic therapy for preventing and treating LV dysfunction and HF in childhood cancer survivors based on expert consensus guidelines and extrapolating data from adult HF trials.

Cardio-oncology for Pediatric and Adolescent/Young Adult Patients

OPINION STATEMENT

As chemotherapy continues to improve the lives of patients with cancer, understanding the effects of these drugs on other organ systems, and the cardiovascular system in particular, has become increasingly important. The effects of chemotherapy on the cardiovascular system are a major determinant of morbidity and mortality in these survivors. Although echocardiography continues to be the most widely used modality for assessing cardiotoxicity, newer imaging modalities and biomarker concentrations may detect subclinical cardiotoxicity earlier. Dexrazoxane continues to be the most effective therapy for preventing anthracycline-induced cardiomyopathy. Neurohormonal modulating drugs have not prevented cardiotoxicity, so their widespread, long-term use for all patients is currently not recommended. Advanced cardiac therapies, including heart transplant, have been successful in cancer survivors with end-stage HF and should be considered for these patients. Research on new targets, especially genetic associations, may produce treatments that help reduce cardiovascular morbidity and mortality.

Specific causes of excess late mortality and association with modifiable risk factors among survivors of childhood cancer: a report from the Childhood Cancer Survivor Study cohort

BACKGROUND

5-year survival after childhood cancer does not fully describe life-years lost due to childhood cancer because there are a large number of deaths occurring beyond 5-years (late mortality) related to cancer and cancer treatment. Specific causes of health-related (non-recurrence, non-external) late mortality and risk reduction through modifiable lifestyle and cardiovascular risk factors are not well described. Through using a well-characterised cohort of 5-year survivors of the most common childhood cancers, we evaluated specific health-related causes of late mortality and excess deaths compared with the general US population and identified targets to reduce future risk.

METHODS

In this multi-institutional, hospital-based, retrospective cohort study, late mortality (death ≥5 years from diagnosis) and specific causes of death were evaluated in 34 230 5-year survivors of childhood cancer diagnosed at an age younger than 21 years from 1970 to 1999 at 31 institutions in the USA and Canada; median follow-up from diagnosis was 29 years (range 5-48) in the Childhood Cancer Survivor Study. Demographic, self-reported modifiable lifestyle (ie, smoking, alcohol, physical activity, and BMI) and cardiovascular risk factors (ie, hypertension, diabetes, and dyslipidaemia) associated with health-related mortality (which excludes death from primary cancer and external causes and includes death from late effects of cancer therapy) were evaluated.

FINDINGS

40-year cumulative all-cause mortality was 23·3% (95% CI 22·7-24·0), with 3061 (51·2%) of 5916 deaths from health-related causes. Survivors 40 years or more from diagnosis experienced 131 excess health-related deaths per 10 000 person-years (95% CI 111-163), including those due to the top three causes of health-related death in the general population: cancer (absolute excess risk per 10 000 person-years 54, 95% CI 41-68), heart disease (27, 18-38), and cerebrovascular disease (10, 5-17). Healthy lifestyle and absence of hypertension and diabetes were each associated with a 20-30% reduction in health-related mortality independent of other factors (all p values ≤0·002).

INTERPRETATION

Survivors of childhood cancer are at excess risk of late mortality even 40 years from diagnosis, due to many of the leading causes of death in the US population. Modifiable lifestyle and cardiovascular risk factors associated with reduced risk for late mortality should be part of future interventions.

FUNDING

US National Cancer Institute and the American Lebanese Syrian Associated Charities.

Diagnosis and Management of Cancer Treatment-Related Cardiac Dysfunction and Heart Failure in Children

It is disheartening for parents to discover that their children have long-term cardiac dysfunction after being cured of life-threatening childhood cancers. As the number of childhood cancer survivors increases, early and late oncology-therapy-related cardiovascular complications continues to rise. It is essential to understand that cardiotoxicity in childhood cancer survivors is persistent and progressive. A child's cancer experience extends throughout his lifetime, and ongoing care for long-term survivors is recognized as an essential part of the cancer care continuum. Initially, there was a lack of recognition of late cardiotoxicities related to cancer therapy. About 38 years ago, in 1984, pioneers like Dr. Lipshultz and others published anecdotal case reports of late cardiotoxicities in children and adolescents exposed to chemotherapy, including some who ended up with heart transplantation. At that time, cardiac tests for cancer survivors were denied by insurance companies because they did not meet appropriate use criteria. Since then, cardio-oncology has been an emerging field of cardiology that focuses on the early detection of cancer therapy-related cardiac dysfunction occurring during and after oncological treatment. The passionate pursuit of many healthcare professionals to make life better for childhood cancer survivors led to more than 10,000 peer-reviewed publications in the last 40 years. We synthesized the existing evidence-based practice and described our experiences in this review to share our current method of surveillance and management of cardiac dysfunction related to cancer therapy. This review aims to discuss the pathological basis of cancer therapy-related cardiac dysfunction and heart failure, how to stratify patients prone to cardiotoxicity by identifying modifiable risk factors, early detection of cardiac dysfunction, and prevention and management of heart failure during and after cancer therapy in children. We emphasize serial longitudinal follow-ups of childhood cancer survivors and targeted intervention for high-risk patients. We describe our experience with the new paradigm of cardio-oncology care, and collaboration between cardiologist and oncologist is needed to maximize cancer survival while minimizing late cardiotoxicity.

Cardio-Oncology in Childhood: State of the Art

PURPOSE OF REVIEW

Cardio-oncology is an increasingly important field of cardiology that focuses on the detection, monitoring, and treatment of cardiovascular disease (CVD) occurring during and after oncological treatments. The survival rate for childhood cancer patients has dramatically increased thanks to new treatment protocols and cardiovascular (CV) sequelae represent the third most frequent cause of mortality in surviving patients. This study aims to provide a complete and updated review of all the main aspects of cardio-oncology in childhood and to highlight the critical issues.

RECENT FINDINGS

The problem of CV complications in childhood cancer survivors raises the need to make an early diagnosis of cardiotoxicity by the new imaging and laboratory techniques in order to intervene promptly and to implement pharmacological strategies and lifestyle changes to reduce or even to prevent cardiac injury. Furthermore, a stratification of CV risk, also including new predisposing factors such as the presence of some genetic mutations, is of paramount importance before undertaking oncological treatments. Besides, a systematic and personalized planning of long-term follow-up is fundamental to ensure a transition from pediatric to adult hospital and to avoid missed or late diagnosis of cardiomyopathy. We reviewed the main risk factors for cardiotoxicity in children, both traditional and emerging ones: the mechanisms of toxicity of both old and new antineoplastic therapies, the techniques for detecting cardiac damage, and the current evidence regarding pharmacological cardioprotection. At the end, we focused our attention on the existing guidelines and strategies about the long-term follow-up of childhood cancer survivors.

Leveraging Clinical Trial Populations and Data from the Children's Oncology Group for Cancer Survivorship Research

Children and adolescents diagnosed with cancer can now expect an average 85% 5-year overall survival, with significant improvements in longer-term morbidity and mortality reported over the past several decades. However, the long-term impact of therapeutic agents and modalities introduced in recent years remains unclear and will require dedicated follow-up in the years ahead. The Children's Oncology Group (COG), a part of the NCI's National Clinical Trials Network, with over 200 sites across North America and beyond, enrolls more than 10,000 patients onto research protocols annually, inclusive of first-line clinical trials and nontherapeutic studies. COG provides a platform to conduct survivorship research with several unique strengths: (i) a huge catchment to ascertain relatively rare but important adverse events, (ii) study populations that are otherwise too rare to study in smaller consortia, including access to highly diverse patient populations, (iii) long-term follow-up of clinical trial populations linked to the original trial data, and (iv) a natural platform for intervention research. Enhancements in COG infrastructure facilitate survivorship research, including a COG patient registry (Project:EveryChild), availability of a long-term follow-up tracking resource, and successful deployment of various remote-based study procedures to reduce the burden on participants and participating institutions.

Delphi Panel Consensus Recommendations for Screening and Managing Childhood Cancer Survivors at Risk for Cardiomyopathy

Background

Cardiomyopathy is a leading cause of late morbidity and mortality in childhood cancer survivors (CCS). Evidence-based guidelines recommend risk-stratified screening for cardiomyopathy, but the management approach for abnormalities detected when screening asymptomatic young adult CCS is poorly defined.

Objectives

The aims of this study were to build upon existing guidelines by describing the expert consensus–based cardiomyopathy screening practices, management approach, and clinical rationale for the management of young adult CCS with screening-detected abnormalities and to identify areas of controversy in practice.

Methods

A multispecialty Delphi panel of 40 physicians with expertise in cancer survivorship completed 3 iterative rounds of semi-open-ended questionnaires regarding their approaches to the management of asymptomatic young adult CCS at risk for cardiomyopathy (screening practices, referrals, cardiac testing, laboratory studies, medications). Consensus was defined as ≥90% panelist agreement with recommendation.

Results

The response rate was 100% for all 3 rounds. Panelists reached consensus on the timing and frequency of echocardiographic screening for anthracycline-associated cardiomyopathy, monitoring during pregnancy, laboratory testing for modifiable cardiac risk factors, and referral to cardiology for ejection fraction ≤50% or preserved ejection fraction with diastolic dysfunction. Controversial areas (<75% agreement) included chest radiation dose threshold to merit screening, indications for advanced cardiac imaging and cardiac serum biomarkers for follow-up of abnormal echocardiographic findings, and medical management of asymptomatic left ventricular systolic dysfunction.

Conclusions

Expert practice is largely consistent with existing risk-based screening guidelines. Some recommendations for managing abnormalities detected on screening echocardiography remain controversial. The rationale offered by experts for divergent approaches may help guide clinical decisions in the absence of guidelines specific to young adult CCS.

Pediatric AML patients with acute-onset cardiomyopathy in the setting of Streptococcus viridans bacteremia after anthracyclines

We reviewed three very similar cases of acute-onset heart failure in children with acute myeloid leukemia who received anthracyclines during their treatment. All three children were diagnosed with recent Streptococcus viridans bacteremia and had persistent tachycardia prior to acute-onset heart failure with near-complete resolution within weeks. We hypothesize their heart failure was secondary to sepsis-induced cardiomyopathy with anthracycline-induced cardiac myocyte damage as a predisposing factor. We suggest prophylaxis and methods of early detection to prevent and better treat acute heart failure in pediatric oncology patients receiving anthracyclines.

Current State of Pediatric Cardio-Oncology: A Review

The landscape of pediatric oncology has dramatically changed over the course of the past several decades with five-year survival rates surpassing 80%. Anthracycline therapy has been the cornerstone of many chemotherapy regimens for pediatric patients since its introduction in the 1960s, and recent improved survival has been in large part due to advancements in chemotherapy, refinement of supportive care treatments, and development of novel therapeutics such as small molecule inhibitors, chimeric antigen receptor T-cell therapy, and immune checkpoint inhibitors. Unfortunately, many cancer-targeted therapies can lead to acute and chronic cardiovascular pathologies. The range of cardiotoxicity can vary but includes symptomatic or asymptotic heart failure, arrhythmias, coronary artery disease, valvar disease, pericardial disease, hypertension, and peripheral vascular disease. There is lack of data guiding primary prevention and treatment strategies in the pediatric population, which leads to substantial practice variability. Several important future research directions have been identified, including as they relate to cardiac disease, prevention strategies, management of cardiovascular risk factors, risk prediction, early detection, and the role of genetic susceptibility in development of cardiotoxicity. Continued collaborative research will be key in advancing the field. The ideal model for pediatric cardio-oncology is a proactive partnership between pediatric cardiologists and oncologists in order to better understand, treat, and ideally prevent cardiac disease in pediatric oncology patients.

Cardiac Disease in Childhood Cancer Survivors: Risk Prediction, Prevention, and Surveillance: JACC CardioOncology State-of-the-Art Review

Cardiac diseases in the growing population of childhood cancer survivors are of major concern. Cardiotoxicity as a consequence of anthracyclines and chest radiotherapy continues to be relevant in the modern treatment era. Mitoxantrone has emerged as an important treatment-related risk factor and evidence on traditional cardiovascular risk factors in childhood cancer survivors is accumulating. International surveillance guidelines have been developed with the aim to detect and manage cardiac diseases early and prevent symptomatic disease. There is growing interest in risk prediction models to individualize prevention and surveillance. This State-of-the-Art Review summarizes literature from a systematic PubMed search focused on cardiac diseases after treatment for childhood cancer. Here, we discuss the prevalence, risk factors, prevention, risk prediction, and surveillance of cardiac diseases in survivors of childhood cancer.

Childhood cancer survivors: The integral role of the cardiologist and cardiovascular imaging

IMPORTANCE

With 80% of childhood cancer survivors (CCS) alive 30 years after diagnosis, preventable causes of death, such as cardiovascular disease resulting from initial cancer therapy, becomes an important metric. This leads to a more pronounced role for cardiologists in the care of CCS.

OBSERVATIONS

While routine cardiovascular screening has been traditionally performed by the hematologist/oncologist or primary care provider, our understanding of cardiovascular disease in CCS has advanced. The measurement of left ventricular ejection fraction (LVEF) can now be complemented with additional assessments of strain, LV mass, right ventricular function, diastolic function, valve function, the pericardium, coronary perfusion, and biomarkers. Risk factor modification, prophylaxis, and timing of treatment are also critical.

CONCLUSIONS AND RELEVANCE

Early cardiovascular screening and treatment in asymptomatic CCS can be nuanced and complex. As a result, there is a renewed opportunity for the cardiologist to play an integral role in the care of CCS.

KEY POINTS

Question/Purpose: Review cardiovascular disease and the role of the cardiologist in the care of asymptomatic childhood cancer survivors (CCS).

FINDINGS

Cardiovascular care in CCS benefits from a multi-faceted approach that does not overly rely on LVEF. Meaning: Adequate screening and treatment of cardiovascular disease in asymptomatic CCS may often be optimized by the involvement of a cardiologist.

Cardiovascular disease and asymptomatic childhood cancer survivors: Current clinical practice

BACKGROUND

It is poorly understood how cardiovascular screening in asymptomatic childhood cancer survivors (CCS) is applied to and impacts clinical care.

OBJECTIVES

To describe the current role of cardiovascular screening in the clinical care of asymptomatic CCS.

METHODS

At 50 pediatric academic medical centers, a childhood cancer survivorship clinic director, pediatric cardiologist, and adult cardiologist with a focus on CCS were identified and invited to participate in a survey. Surveys were managed electronically. Categorical data were analyzed using nonparametric methods.

RESULTS

Of the 95 (63%) respondents, 39% were survivorship practitioners, and 61% were cardiologists. Eighty-eight percent of survivorship practitioners reported that greater than half of CCS received cardiovascular screening. CCS followed by adult cardiology were more likely to be seen by a cardio-oncologist. Those followed by pediatric cardiology were more likely to be seen by a heart failure/transplant specialist. Common reasons for referral to cardiology were abnormal cardiovascular imaging or concerns a CCS was at high risk for cardiovascular disease. Ninety-two percent of cardiologists initiated angiotensin converting enzyme inhibitor or angiotensin receptor blocker therapy for mild systolic dysfunction. Adult cardiologists initiated beta-blocker therapy for less severe systolic dysfunction compared to pediatric cardiologists (P < .001). Pediatric cardiologists initiated mineralocorticoid therapy for less severe systolic dysfunction compared to adult cardiologists (P = .025). Practitioners (93%) support a multi-institutional collaboration to standardize cardiovascular care for CCS.

CONCLUSIONS

While there is much common ground in the clinical approach to CCS, heterogeneity is evident. This highlights the need for cohesive, multi-institutional, standardized approaches to cardiovascular management in CCS.

Ischaemic heart disease and Cancer: competing malignant conditions

BACKGROUND

The growing population of cancer survivors and their high frequency of cardiovascular disease have resulted in a dramatic increase in cancer patients requiring cardiovascular intervention. However, there is a lack of evidence to guide optimal management in this complex population who have historically been excluded from cardiovascular trials.

DISCUSSION

We review the recently published meta-analysis by Roule et al. The findings of this analysis demonstrate that patients with cancer presenting with acute coronary syndrome (ACS) have increased rates of in-hospital cardiovascular mortality, bleeding and one-year cardiovascular mortality. All-cause mortality measured in-hospital and at one-year were also significantly greater in cancer patients as was all-cause mortality in cancer patients that undergo percutaneous coronary intervention (PCI). In contrast to the short-term outcomes, rates of long-term cardiovascular mortality did not differ significantly between groups. Patient-specific assessment of risk, accounting for disease characteristics and treatment, and close communication with oncology providers is vital in defining optimal treatment strategies in this population.

Premature Aging in Young Cancer Survivors

Advances in early detection, treatment, and supportive care have resulted in an estimated 16 million cancer survivors who are alive in the United States today. Outcomes have notably improved for children with cancer as well as young adults with hematologic malignancies due, in part, to the intensification of cancer treatment, including the use of hematopoietic cell transplantation. Emerging evidence suggests that these cancer survivors are at risk for premature aging, manifesting as early onset of chronic health conditions and a higher risk of mortality compared with the general population. Although the pathophysiology of premature aging in these survivors has not been fully elucidated, emerging concepts in aging research could help shed light on this phenomenon. Longitudinal studies are needed to better characterize aging in these survivors, setting the stage for much-needed interventions to halt the trajectory of accelerated aging. These efforts will be enhanced through collaborations between translational researchers, clinical oncologists, primary care providers, geriatricians, patient caretakers, and other stakeholders committed to improving the lives of the growing population of survivors.

Cardiovascular Toxicities in Pediatric Cancer Survivors

Advances in cancer therapies have significantly improved patient outcomes. However, with improvements in survival, the toxicities associated with cancer therapy have become of paramount importance and oncologists are faced with the challenge of establishing therapeutic efficacy while minimizing toxicity. Cardiovascular disease represents a significant risk to survivors of childhood cancer and is a major cause of morbidity and mortality. This article outlines the current state of knowledge regarding cardiotoxicity in children undergoing cancer therapies, including the impact of specific oncologic therapies, recommendations for cardiovascular screening, the management of established cardiac disease, and the evolving field of pediatric cardio-oncology.

Subclinical Cardiac Dysfunction in Childhood Cancer Survivors on 10-Years Follow-Up Correlates With Cumulative Anthracycline Dose and Is Best Detected by Cardiopulmonary Exercise Testing, Circulating Serum Biomarker, Speckle Tracking Echocardiography, and Tissue Doppler Imaging

Background: Survivors of childhood cancer are at risk for anthracycline- and/or radiotherapy-induced cardiotoxicity. Aims: The aim of this study was to assess clinical, laboratory, and imaging parameters of subclinical cardiovascular disease in childhood cancer survivors. Methods: Patients underwent cardiopulmonary exercise test (CPET), laboratory testing, transthoracic echocardiography (TTE) with tissue doppler imaging (TDI) and speckle tracking. A subset of patients also underwent cardiovascular magnetic resonance imaging (CMR). Findings were correlated to cumulative anthracycline and exposure to mediastinal irradiation during cancer treatment. In a subgroup analysis, TTE and CMR findings were compared to data from 40 gender- and age-matched patients with childhood onset hypertrophic cardiomyopathy (HCM). Results: Cardiac evaluation was performed in 79 patients (43 males) at 11.2 ± 4.5 years after cancer treatment. Oncologic diagnosis at a median age of 12.0 years was Hodgkin lymphoma in 20, sarcoma in 17, acute leukemia in 24, relapse leukemia in 10, and others in 8 patients. Cumulative anthracycline dose exceeded 300 mg/m² in 28 patients. Twenty six patients also received mediastinal irradiation. Decreased peak respiratory oxygen uptake in % predicted on CPET, increased levels of N-terminal pro-brain natriuretic peptide (NTproBNP), increased global longitudinal strain on TTE speckle tracking, and diastolic dysfunction on TDI were the most prominent findings on detailed cardiology follow-up. In contrast to HCM patients, childhood cancer survivors did not show left ventricular hypertrophy (LVPWd z-score median 0.9 vs. 2.8, p < 0.001), hyperdynamic systolic function on TTE (Ejection fraction 62 ± 7 vs. 72 ± 12%, p = 0.001), or fibrotic myocardial changes on CMR (Late gadolinium positive 0/13 vs. 13/36, p = 0.001; extracellular volume fraction 22 ± 2 vs. 28 ± 3, p < 0.001) at time of follow-up. There was no correlation between chest radiation exposure and abnormal cardiac findings. Cumulative anthracycline dose was the only significant independent predictor on multivariate analysis for any cardiovascular abnormality on follow-up (p = 0.036). Conclusion: Increasing cumulative anthracycline dose during cancer treatment correlates with subclinical cardiac dysfunction in childhood cancer survivors best detected by elevated cardiac serum biomarkers, decreased exercise capacity on CPET, and abnormalities on echocardiographic speckle tracking and TDI.

Strategies to prevent anthracycline-induced cardiotoxicity in cancer survivors

Cancer diagnostics and therapies have improved steadily over the last few decades, markedly increasing life expectancy for patients at all ages. However, conventional and newer anti-neoplastic therapies can cause short- and long-term cardiotoxicity. The clinical implications of this cardiotoxicity become more important with the increasing use of cardiotoxic drugs. The implications are especially serious among patients predisposed to adverse cardiac effects, such as youth, the elderly, those with cardiovascular comorbidities, and those receiving additional chemotherapies or thoracic radiation. However, the optimal strategy for preventing and managing chemotherapy-induced cardiotoxicity remains unknown. The routine use of neurohormonal antagonists for cardioprotection is not currently justified, given the marginal benefits and associated adverse events, particularly with long-term use. The only United States Food and Drug Administration and European Medicines Agency approved treatment for preventing anthracycline-related cardiomyopathy is dexrazoxane. We advocate administering dexrazoxane during cancer treatment to limit the cardiotoxic effects of anthracycline chemotherapy.

The landscape of cardiovascular care in pediatric cancer patients and survivors: a survey by the ACC Pediatric Cardio-Oncology Work Group

Objective

To enhance the understanding of cardiovascular care delivery in childhood cancer patients and survivors.

Study design

A 20-question survey was created by the Pediatric Cardio-oncology Work Group of the American College of Cardiology (ACC) Cardio-oncology Section to assess the care, management, and surveillance tools utilized to manage pediatric/young adult cardio-oncology patients. The survey distribution was a collaborative effort between Cardio-oncology Section and membership of the Adult Congenital and Pediatric Cardiology Section (ACPC) of the ACC.

Results

Sixty-five individuals, all self-identified as physicians, responded to the survey. Most respondents (n = 58,89%) indicated childhood cancer patients are regularly screened prior to and during cancer therapy at their centers, predominantly by electrocardiogram (75%), standard echocardiogram (58%) and advanced echocardiogram (50%) (i.e. strain, stress echo). Evaluation by a cardiologist prior to/during therapy was reported by only 8(12%) respondents, as compared to post-therapy which was reported by 28 (43%, p < 0.01). The most common indications for referral to cardiology at pediatric centers were abnormal test results (n = 31,48%) and history of chemotherapy exposure (n = 27,42%). Of note, during post-treatment counseling, common cardiovascular risk-factors like blood pressure (31,48%), lipid control (22,34%), obesity & smoking (30,46%) and diet/exercise/weight loss (30,46%) were addressed by fewer respondents than was LV function (72%).

Conclusions

The survey data demonstrates that pediatric cancer patients are being screened by EKG and/or imaging prior to/during therapy at most centers. Our data, however, highlight the potential for greater involvement of a cardiovascular specialist for pre-treatment evaluation process, and for more systematic cardiac risk factor counseling in posttreatment cancer survivors.

Heart transplantation in survivors of childhood cancer

There are approximately 450,000 survivors of childhood cancer due, in large part, to successes of therapeutic regimens. With this success comes an increase in the number of patients developing cardiotoxicity as a result of cancer therapies. In certain cases, this includes heart failure recalcitrant to medical therapy, and consideration for heart transplantation may be necessary. However, this group of patients has unique comorbidities that may affect outcomes. Despite this, available data show that complications and overall survival are similar for patients transplanted for anthracycline-induced cardiomyopathy compared to those with other cardiomyopathies, demonstrating that this is a viable treatment option for this population. As other cancer therapies become more common, new cardiovascular toxicities are recognized. Whether heart transplantation will be appropriate for all patients with cancer-therapy related cardiotoxicity (CTRC) will require demonstration of similarly good outcomes to ensure proper allocation of organs.

Closing the survivorship gap in children and adolescents with Hodgkin lymphoma

The treatment of Hodgkin lymphoma (HL) is one of early success. However, disease-free survival (DFS) does not reflect latent organ injury and its impact on health status and well-being beyond 5 years. In fact, we are at a crossroads, in terms of needing individualized approaches to maintain DFS, while minimizing late effects and preserving health-related quality of life (HRQoL). Premature morbidity and mortality translate to a high societal cost associated with the potential number of productive life years ahead in this population who are young at diagnosis. The discordance between short-term lymphoma-free survival and long-term health and HRQoL creates a "survivorship gap" which can be characterized for individuals and for subgroups of patients. The current review delineates contributors to compromised outcomes and health status in child and adolescent (paediatric) HL and frames the survivorship gap in terms of primary and secondary prevention. Primary prevention aims to titrate therapy. Secondary prevention entails strategies to intervene against late effects. Bridging the survivorship gap will be attained with enhanced knowledge of and attention to biology of the tumour and microenvironment, host genetic factors, HRQoL and sub-populations with disparate outcomes.

Pediatric Cardio-Oncology: Development of Cancer Treatment-Related Cardiotoxicity and the Therapeutic Approach to Affected Patients

OPINION STATEMENT

The past 5 decades have seen significant improvements in outcomes for pediatric patients with cancer. Unfortunately, children and adolescents who have been treated for cancer are five to six times more likely to develop cardiovascular disease as a result of their therapies. Cardiovascular disease may manifest in a plethora of ways, from asymptomatic ventricular dysfunction to end-stage heart failure, hypertension, arrhythmia, valvular disease, early coronary artery disease, or peripheral vascular disease. A number of treatment modalities are implicated in pediatric and adult populations, including anthracyclines, radiation therapy, alkylating agents, targeted cancer therapies (small molecules and antibody therapies), antimetabolites, antimicrotubule agents, immunotherapy, interleukins, and chimeric antigen receptor T cells. For some therapies, such as anthracyclines, the mechanism of injury is elucidated, but for many others it is not. While a few protective strategies exist, in many cases, observation and close monitoring is the only defense against developing end-stage cardiovascular disease. Because of the variety of potential outcomes after cancer therapy, a one-size-fits-all approach is not appropriate. Rather, a good working relationship between oncology and cardiology to assess the risks and benefits of various therapies and planning for appropriate surveillance is the best model. When disease is identified, any of a number of therapies may be appropriate; however, in the pediatric and adolescent population supportive data are limited.

Prediction of cardiovascular disease among hematopoietic cell transplantation survivors

Cardiovascular disease (CVD) is a leading cause of late morbidity and mortality in hematopoietic cell transplantation (HCT) survivors. HCT-specific CVD risk prediction models are needed to facilitate early screening and prevention. In the current study, patients who underwent HCT at City of Hope (COH) and survived 1-year free of clinically evident CVD (N = 1828) were observed for the development of heart failure (HF) or coronary artery disease (CAD) by 10-years from index date (1 year from HCT). CVD occurred in 135 individuals (92 HF, 43 CAD). Risk prediction models were developed for overall CVD (HF and/or CAD) using COH-derived integer risk scores. Risk scores based on selected variables (age, anthracycline dose, chest radiation, hypertension, diabetes, smoking) achieved an area under the curve (AUC) and concordance (C) statistic of 0.74 and 0.72 for CVD; these varied from 0.70 to 0.82 according to CVD subtype (HF or CAD). A Fred Hutchinson Cancer Research Center case cohort (N = 580) was used to validate the COH models. Validation cohort AUCs ranged from 0.66 to 0.75. Risk scores were collapsed to form statistically distinct low-, intermediate-, and high-risk groups, corresponding to 10-year cumulative incidences of CVD of 3.7%, 9.9%, and 26.2%, respectively. Individuals in the high- and intermediate-risk groups were at 7.8-fold (95% confidence interval, 5.0-12.2) and 2.9-fold (95% confidence interval, 1.9-4.6) risk of developing CVD (referent group: low risk). These validated models provide a framework on which to modify current screening recommendations and for the development of targeted interventions to reduce the risk of CVD after HCT.

Preventive use of carvedilol for anthracycline-induced cardiotoxicity: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Clinical or subclinical cardiotoxicity is a concern for cancer patients receiving anthracycline-based chemotherapy. Carvedilol is promising for preventing anthracycline-induced cardiotoxicity (AIC). This review appraised the preventive effects of carvedilol against AIC based on randomized controlled trials (RCTs).

METHODS

The Cochrane Collaboration Central Register of Controlled Trials, PubMed, and Embase databases were searched from inception to March 27, 2018. RCTs using carvedilol for the prevention of AIC were selected. Risk of bias and methodological quality were assessed. Meta-analysis was conducted, when applicable, for the trial endpoints; otherwise the data were analyzed descriptively.

RESULTS

Nine RCTs comprising 717 patients were selected. The risk of bias was unclear and the methodological quality differed substantially. Data pooling of five eligible studies indicated no decreased mortality in patients receiving carvedilol (risk difference = -0.02, 95% CI: -0.07-0.04, p = 0.57, I² = 44%). The impact on the incidence of left ventricular systolic dysfunction (LVSD) was inconsistently reported but meta-analysis was not applicable due to discordant LVSD definitions. Data pooling of eight studies and a subgroup analysis indicated a higher left ventricular ejection fraction (LVEF) with substantial heterogeneity in the carvedilol group (mean difference [MD] = 5.23, 95% CI: 2.20-8.27, p = 0.0007, I² = 95%, and MD = 4.65, 95% CI: 0.67-8.64, p = 0.02, I² = 90%, respectively). Further analysis of echocardiographic parameters and biomarkers showed weak evidence of improvement in diastolic function and troponin I level by carvedilol administration.

CONCLUSION

Preventive use of carvedilol in patients undergoing anthracycline-based chemotherapy may be associated with a reduced incidence of LVSD, higher LVEF value, better diastolic function, and lower troponin I level. RCTs with larger sample size and longer follow-up are needed to verify these findings.

Predicting and Preventing Anthracycline-Related Cardiotoxicity

Anthracyclines (doxorubicin, daunorubicin, epirubicin, and idarubicin) are among the most potent chemotherapeutic agents and have truly revolutionized the management of childhood cancer. They form the backbone of chemotherapy regimens used to treat childhood acute lymphoblastic leukemia, acute myeloid leukemia, Hodgkin lymphoma, Ewing sarcoma, osteosarcoma, and neuroblastoma. More than 50% of children with cancer are treated with anthracyclines. The clinical utility of anthracyclines is compromised by dose-dependent cardiotoxicity, manifesting initially as asymptomatic cardiac dysfunction and evolving irreversibly to congestive heart failure. Childhood cancer survivors are at a five- to 15-fold increased risk for congestive heart failure compared with the general population. Once diagnosed with congestive heart failure, the 5-year survival rate is less than 50%. Prediction models have been developed for childhood cancer survivors (i.e., after exposure to anthracyclines) to identify those at increased risk for cardiotoxicity. Studies are currently under way to test risk-reducing strategies. There remains a critical need to identify patients with childhood cancer at diagnosis (i.e., prior to anthracycline exposure) such that noncardiotoxic therapies can be contemplated.

Evidence for Genetic Risk Contributing to Long-Term Adverse Treatment Effects in Childhood Cancer Survivors

Survivors of childhood cancer are at increased risk for therapy-related morbidities and mortality. Although the demographic and clinical factors predicting the risk for long-term effects of cancer therapy are well known, the impact of genetic risk for specific late effects is less clearly defined. Here, we review the extant literature and recent research describing genetic modifiers to risk for the more common late effects of childhood cancer therapy. Results of this research support the need for clinical trials that attempt to further refine risk prediction by incorporating genetic testing into existing algorithms that are primarily based on clinical and demographic factors. Confirmation of genetic predisposition, as defined by reproducibility and prospective validation, would permit therapeutic modification and discussion of individualized survivor care plans even at initial cancer diagnosis.