Longitudinal Changes in Echocardiographic Parameters of Cardiac Function in Pediatric Cancer Survivors

Building a machine learning-assisted echocardiography prediction tool for children at risk for cancer therapy-related cardiomyopathy

BACKGROUND

Despite routine echocardiographic surveillance for childhood cancer survivors, the ability to predict cardiomyopathy risk in individual patients is limited. We explored the feasibility and optimal processes for machine learning-enhanced cardiomyopathy prediction in survivors using serial echocardiograms from five centers.

METHODS

We designed a series of deep convolutional neural networks (DCNNs) for prediction of cardiomyopathy (shortening fraction ≤ 28% or ejection fraction ≤ 50% on two occasions) for at-risk survivors ≥ 1-year post initial cancer therapy. We built DCNNs with four subsets of echocardiographic data differing in timing relative to case (survivor who developed cardiomyopathy) index diagnosis and two input formats (montages) with differing image selections. We used holdout subsets in a 10-fold cross-validation framework and standard metrics to assess model performance (e.g., F1-score, area under the precision-recall curve [AUPRC]). Performance of the input formats was compared using a combined 5 × 2 cross-validation F-test.

RESULTS

The dataset included 542 pairs of montages: 171 montage pairs from 45 cases at time of cardiomyopathy diagnosis or pre-diagnosis and 371 pairs from 70 at-risk survivors who didn't develop cardiomyopathy during follow-up (non-case). The DCNN trained to distinguish between non-case and time of cardiomyopathy diagnosis or pre-diagnosis case montages achieved an AUROC of 0.89 ± 0.02, AUPRC 0.83 ± 0.03, and F1-score: 0.76 ± 0.04. When limited to smaller subsets of case data (e.g., ≥ 1 or 2 years pre-diagnosis), performance worsened. Model input format did not impact performance accuracy across models.

CONCLUSIONS

This methodology is a promising first step toward development of a DCNN capable of accurately differentiating pre-diagnosis versus non-case echocardiograms to predict survivors more likely to develop cardiomyopathy.

Cardio-Oncology and Heart Failure: A Scientific Statement from the Heart Failure Society of America

Heart failure and cancer remain two of the leading causes of morbidity and mortality and the two disease entities are linked in a complex manner. Patients with cancer are at increased risk of cardiovascular complications related to the cancer therapies. The presence of cardiomyopathy or heart failure in a patient with new cancer diagnosis portends a high risk for adverse oncology and cardiovascular outcomes. With the rapid growth of cancer therapies, many of which interfere with cardiovascular homeostasis, heart failure practitioners need to be familiar with prevention, risk stratification, diagnosis, and management strategies in cardio-oncology. This Heart Failure Society of America statement addresses the complexities of heart failure care among patients with active cancer diagnosis and cancer survivors. Risk stratification, monitoring, and management of cardiotoxicity are presented across Stages A through D heart failure, with focused discussion on heart failure preserved ejection fraction and special populations such as survivors of childhood and young adulthood cancers. We provide an overview of the shared risk factors between cancer and heart failure, highlighting heart failure as a form of cardiotoxicity associated with many different cancer therapeutics. Finally, we discuss disparities in the care of patients with cancer and cardiac disease and present a framework for a multidisciplinary team approach and critical collaboration between heart failure, oncology, palliative care, pharmacy, and nursing teams in the management of these complex patients.

High-Fat Diet Augments Myocardial Inflammation and Cardiac Dysfunction in Arrhythmogenic Cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is a familial heart disease characterized by cardiac dysfunction, arrhythmias, and myocardial inflammation. Exercise and stress can influence the disease's progression. Thus, an investigation of whether a high-fat diet (HFD) contributes to ACM pathogenesis is warranted. In a robust ACM mouse model, 8-week-old Desmoglein-2 mutant (Dsg2mut/mut) mice were fed either an HFD or rodent chow for 8 weeks. Chow-fed wildtype (WT) mice served as controls. Echo- and electrocardiography images pre- and post-dietary intervention were obtained, and the lipid burden, inflammatory markers, and myocardial fibrosis were assessed at the study endpoint. HFD-fed Dsg2mut/mut mice showed numerous P-wave perturbations, reduced R-amplitude, left ventricle (LV) remodeling, and reduced ejection fraction (%LVEF). Notable elevations in plasma high-density lipoprotein (HDL) were observed, which correlated with the %LVEF. The myocardial inflammatory adipokines, adiponectin (AdipoQ) and fibroblast growth factor-1, were substantially elevated in HFD-fed Dsg2mut/mut mice, albeit no compounding effect was observed in cardiac fibrosis. The HFD not only potentiated cardiac dysfunction but additionally promoted adverse cardiac remodeling. Further investigation is warranted, particularly given elevated AdipoQ levels and the positive correlation of HDL with the %LVEF, which may suggest a protective effect. Altogether, the HFD worsened some, but not all, disease phenotypes in Dsg2mut/mut mice. Notwithstanding, diet may be a modifiable environmental factor in ACM disease progression.

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.

Utility of apical four-chamber longitudinal strain in the assessment of childhood cancer survivors: A multicenter study

BACKGROUND

A previous multicenter study showed that longitudinal changes in standard cardiac functional parameters were associated with the development of cardiomyopathy in childhood cancer survivors (CCS). Evaluation of the relationship between global longitudinal strain (GLS) changes and cardiomyopathy risk was limited, largely due to lack of quality apical 2- and 3-chamber views in addition to 4-chamber view. We sought to determine whether apical 4-chamber longitudinal strain (A4LS) alone can serve as a suitable surrogate for GLS in this population.

METHODS

A4LS and GLS were measured in echocardiograms with acceptable apical 2-, 3-, and 4-chamber views. Correlation was evaluated using Pearson and Spearman coefficients, and agreement was evaluated with Bland-Altman plots. The ability of A4LS to identify normal and abnormal values compared to GLS as the reference was evaluated.

RESULTS

Among a total of 632 reviewed echocardiograms, we identified 130 echocardiograms from 56 patients with adequate views (38% female; mean age at cancer diagnosis 8.3 years; mean follow-up 9.4 years). Correlation coefficients between A4LS and GLS were .89 (Pearson) and .85 (Spearman), with Bland-Altman plot of GLS-A4LS showing a mean difference of -.71 ± 1.8. Compared with GLS as the gold standard, A4LS had a sensitivity of 86% (95% CI 79%-93%) and specificity of 82% (69%-95%) when using normal range cutoffs and 90% (82%-97%) and 70% (58%-81%) when using ±2 standard deviations.

CONCLUSION

A4LS performs well when compared with GLS in this population. Given the more recent adoption of apical 2- and 3-chamber views in most pediatric echocardiography laboratories, A4LS is a reasonable stand-alone measurement in retrospective analyses of older study cohorts and echocardiogram biorepositories.

Impact of Cancer Type and Treatment Protocol on Cardiac Function in Pediatric Oncology Patients: An Analysis Utilizing Speckle Tracking, Global Longitudinal Strain, and Myocardial Performance Index

Pediatric hemato-oncology patients undergoing anthracycline therapy are at risk of cardiotoxicity, with disease type and treatment intensity potentially affecting cardiac function. Novel echocardiographic measures like speckle tracking echocardiography (STE), global longitudinal strain (GLS), and the myocardial performance index (MPI) may predict early changes in cardiac function not detected by traditional methods. This study aimed to assess the impact of cancer type and treatment protocol on these parameters and their potential in predicting long-term cardiac complications. We conducted a single-center, retrospective cohort study of 99 pediatric oncology patients and 46 controls that were assessed at 3, 6, and 12 months. The median age was 10.7 ± 4.4 years for cases and 10.2 ± 3.6 years for controls. STE, GLS, and MPI were measured, and statistical analyses were performed to determine any significant correlations with cardiotoxicity. Significant variations were observed in traditional cardiac function measurements between the patient and control groups, with a lower average ejection fraction (EF) of 62.8 ± 5.7% in patients vs. 66.4 ± 6.1% in controls (p < 0.001), poorer GLS of -16.3 ± 5.1 in patients compared to -19.0 ± 5.4 in controls (p = 0.004), and higher MPI values of 0.37 ± 0.06 in patients compared to 0.55 ± 0.10 in controls, indicating worse overall cardiac function (p < 0.001). However, differences in cardiac function measurements by cancer histology or treatment protocol were not statistically significant. Regression analyses showed that the combination of GLS, SMOD, and MPI increased the odds of cardiac toxicity with an odds ratio of 7.30 (95% CI: 2.65-12.81, p < 0.001). The study underscores the predictive value of the combined GLS, SMOD, and MPI measurements in pediatric oncology patients undergoing anthracycline treatment for cardiotoxicity. Although variations across cancer types and treatment protocols were not significant, the study emphasizes the potential utility of these novel echocardiographic measures in early detection and long-term prediction of anthracycline-induced cardiotoxicity. Further studies in larger, multi-center cohorts are required for validation.

Tales from the future-nuclear cardio-oncology, from prediction to diagnosis and monitoring

Cancer and cardiovascular diseases (CVD) often share common risk factors, and patients with CVD who develop cancer are at high risk of experiencing major adverse cardiovascular events. Additionally, cancer treatment can induce short- and long-term adverse cardiovascular events. Given the improvement in oncological patients' prognosis, the burden in this vulnerable population is slowly shifting towards increased cardiovascular mortality. Consequently, the field of cardio-oncology is steadily expanding, prompting the need for new markers to stratify and monitor the cardiovascular risk in oncological patients before, during, and after the completion of treatment. Advanced non-invasive cardiac imaging has raised great interest in the early detection of CVD and cardiotoxicity in oncological patients. Nuclear medicine has long been a pivotal exam to robustly assess and monitor the cardiac function of patients undergoing potentially cardiotoxic chemotherapies. In addition, recent radiotracers have shown great interest in the early detection of cancer-treatment-related cardiotoxicity. In this review, we summarize the current and emerging nuclear cardiology tools that can help identify cardiotoxicity and assess the cardiovascular risk in patients undergoing cancer treatments and discuss the specific role of nuclear cardiology alongside other non-invasive imaging techniques.

Dexrazoxane and Long-Term Heart Function in Survivors of Childhood Cancer

PURPOSE

For survivors of childhood cancer treated with doxorubicin, dexrazoxane is cardioprotective for at least 5 years. However, longer-term data are lacking.

METHODS

Within the Children's Oncology Group and the Dana Farber Cancer Institute's Childhood Acute Lymphoblastic Leukemia Consortium, we evaluated four randomized trials of children with acute lymphoblastic leukemia or Hodgkin lymphoma, who received doxorubicin with or without dexrazoxane, and a nonrandomized trial of patients with osteosarcoma who all received doxorubicin with dexrazoxane. Cumulative doxorubicin doses ranged from 100 to 600 mg/m2 across these five trials, and dexrazoxane was administered uniformly (10:1 mg/m2 ratio) as an intravenous bolus before doxorubicin. Cardiac function was prospectively assessed in survivors from these trials, plus a matched group of survivors of osteosarcoma treated with doxorubicin without dexrazoxane. Two-dimensional echocardiograms and blood biomarkers were analyzed centrally in blinded fashion. Multivariate analyses adjusted for demographic characteristics, cumulative doxorubicin dose, and chest radiotherapy determined the differences and associations by dexrazoxane status.

RESULTS

From 49 participating institutions, 195 participants were assessed at 18.1 ± 2.7 years since cancer diagnosis (51% dexrazoxane-exposed; cumulative doxorubicin dose 297 ± 91 mg/m2). Dexrazoxane administration was associated with superior left ventricular fractional shortening (absolute difference, +1.4% [95% CI, 0.3 to 2.5]) and ejection fraction (absolute difference, +1.6% [95% CI, 0.0 to 3.2]), and lower myocardial stress per B-type natriuretic peptide (-6.7 pg/mL [95% CI, -10.6 to -2.8]). Dexrazoxane was associated with a reduced risk of having lower left ventricular function (fractional shortening < 30% or ejection fraction < 50%; odds ratio, 0.24 [95% CI, 0.07 to 0.81]). This protective association was primarily seen in those treated with cumulative doxorubicin doses ≥ 250 mg/m2.

CONCLUSION

Among young adult-aged survivors of childhood cancer, dexrazoxane was associated with a cardioprotective effect nearly 20 years after initial anthracycline exposure.

Cardiac Imaging in Childhood Cancer Survivors: A State-of-the-Art Review

Childhood cancer survival has improved significantly in the past few decades, reaching rates of 80% or more at 5 years. However, with improved survival, early- and late-occurring complications of chemotherapy and radiotherapy exposure are becoming progressively more evident. Cardiovascular diseases represent the leading cause of non-oncological morbidity and mortality in this highly vulnerable population. Therefore, the necessity of reliable, noninvasive screening tools able to early identify cardiac complications early is now pre-eminent in order to implement prevention strategies and mitigate disease progression. Echocardiography, may allow identification of myocardial dysfunction, pericardial complications, and valvular heart diseases. However, additional imaging modalities may be necessary in selected cases. This manuscript provides an in-depth review of noninvasive imaging parameters studied in childhood cancer survivors. Furthermore, we will illustrate brief surveillance recommendations according to available evidence and future perspectives in this expanding field.

Systematic review and updated recommendations for cardiomyopathy surveillance for survivors of childhood, adolescent, and young adult cancer from the International Late Effects of Childhood Cancer Guideline Harmonization Group

Survivors of childhood, adolescent, and young adult cancer, previously treated with anthracycline chemotherapy (including mitoxantrone) or radiotherapy in which the heart was exposed, are at increased risk of cardiomyopathy. Symptomatic cardiomyopathy is typically preceded by a series of gradually progressive, asymptomatic changes in structure and function of the heart that can be ameliorated with treatment, prompting specialist organisations to endorse guidelines on cardiac surveillance in at-risk survivors of cancer. In 2015, the International Late Effects of Childhood Cancer Guideline Harmonization Group compiled these guidelines into a uniform set of recommendations applicable to a broad spectrum of clinical environments with varying resource availabilities. Since then, additional studies have provided insight into dose thresholds associated with a risk of asymptomatic and symptomatic cardiomyopathy, have characterised risk over time, and have established the cost-effectiveness of different surveillance strategies. This systematic Review and guideline provides updated recommendations based on the evidence published up to September, 2020.

Correlating decline in left ventricular ejection fraction and longitudinal strain in pediatric cancer patients

PURPOSE

Left ventricular ejection fraction (LVEF) is routinely used to monitor cardiac function in cancer patients. Global longitudinal strain (GLS) detects subclinical myocardial dysfunction. There is no consensus on what constitutes a significant change in GLS in pediatric cancer patients. We aim to determine the change in GLS associated with a simultaneous decline in LVEF in pediatric cancer patients.

METHODS

This is a retrospective longitudinal study of pediatric cancer patients treated with anthracyclines between October 2017 and November 2019. GLS was measured by 2-dimensional speckle tracking. The study outcome was a decline in LVEF, defined as a decrease in LVEF of ≥ 10% points from baseline or LVEF < 55%. We evaluated two echocardiograms per patient, one baseline, and one follow-up. The follow-up echocardiogram was either (1) the first study that met the outcome or (2) the last echocardiogram available in patients without the outcome. Statistical analyses included receiver operator characteristic curves and univariable and multivariable Cox proportional hazards regression.

RESULTS

Out of 161 patients, 33 (20.5%) had a decline in LVEF within one year of follow-up. GLS reduction by ≥ 15% from baseline and follow-up GLS >-18% had sensitivities of 85% and 78%, respectively, and specificities of 86% and 83%, respectively, to detect LVEF decline. GLS reduction by ≥ 15% from baseline and follow-up GLS >-18% were independently associated with simultaneous LVEF decline [hazard ratio (95% confidence intervals): 16.71 (5.47-51.06), and 12.83 (4.62-35.63), respectively].

CONCLUSION

Monitoring GLS validates the decline in LVEF in pediatric cancer patients.

Myocardial Dysfunction in Patients with Cancer

Myocardial dysfunction in patients with cancer is a major cause of morbidity and mortality. Cancer therapy-related cardiotoxicities are an important contributor to the development of cardiomyopathy in this patient population. Furthermore, cardiac AL amyloidosis, cardiac malignancies/metastases, accelerated atherosclerosis, stress cardiomyopathy, systemic and pulmonary hypertension are also linked to the development of myocardial dysfunction. Herein, we summarize current knowledge on the mechanisms of myocardial dysfunction in the setting of cancer and cancer-related therapies. Additionally, we briefly outline key recommendations on the surveillance and management of cancer therapy-related myocardial dysfunction based on the consensus of experts in the field of cardio-oncology.

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.

Cardiotoxicidad por antraciclinas en supervivientes de cáncer durante la infancia

Introducción: a nivel mundial, cada año cerca de 300.000 niños entre 0 y 19 años son diagnosticados con cáncer. El porcentaje de supervivientes va en aumento, llegando a 80 % en países desarrollados y 60 % en América Latina. Sin embargo, la expectativa y la calidad de vida de estas personas pueden verse comprometidas ante el desarrollo de cardiotoxicidad, un efecto adverso asociado al uso de algunos agentes antineoplásicos, como los antracíclicos.Objetivo: resaltar los aspectos clínicos relevantes para la prevención, detección oportuna, tratamiento y seguimiento de la cardiotoxicidad secundaria a la administración de antraciclinas durante la infancia.Síntesis de contenido: reflexión teórica que presenta consideraciones clínicas relevantes para guiar las acciones de enfermería y del equipo multidisciplinario en la atención y el cuidado de la salud cardiovascular de los supervivientes de cáncer a cualquier edad. Es importante destacar que en población pediátrica la única estrategia efectiva de prevención primaria para cardiotoxicidad por antraciclinas es la administración de dexrazoxano, mientras que la prevención secundaria debe incluir detección oportuna, control y  seguimiento de las alteraciones de la función cardíaca y de los factores de riesgo cardiovascular. Por su parte, la prevención terciaria se centra en el control de la enfermedad y el manejo farmacológico. Conclusiones: no existe un  tratamiento estándar para la cardiotoxicidad inducida por quimioterapia o radioterapia, siendo el objetivo principal de este tipo de tratamientos prevenir o retrasar la remodelación del ventrículo izquierdo. Todos los supervivientes requieren seguimiento vitalicio y búsqueda activa de signos de cardiotoxicidad, siendo fundamental la acción conjunta de diferentes profesionales y la consolidación de los servicios de cardio-oncología.

Association of persistent tachycardia with early myocardial dysfunction in children undergoing allogeneic hematopoietic cell transplantation

Cancer survivors who have undergone hematopoietic cell transplantation (HCT) are at risk for myocardial dysfunction. Children who receive allogenic HCT encounter systemic inflammation resulting in tachycardia and hypertension. The effect of these abnormalities on myocardial function is not known. The aim of this study was to determine whether cardiac dysfunction early after HCT can be predicted by tachycardia or hypertension, within a retrospective single-center sample of pediatric HCT recipients. Early tachycardia or hypertension was defined as a majority of values taken from infusion date to 90 days post-infusion being abnormal. Ejection fraction <53% determined systolic dysfunction. A composite score of accepted pediatric diastolic abnormalities determined diastolic dysfunction. Among 80 subjects (median age 8 years), early tachycardia, systolic dysfunction, and diastolic dysfunction were present in 64%, 25%, and 48% of the sample, respectively. In multivariable models, early tachycardia was an independent predictor of early systolic dysfunction (OR = 12.6 [1.4-112.8], p = 0.024) and diastolic dysfunction (OR = 3.9 [1.3-11.5], p = 0.013). Tachycardia and cardiac dysfunction are common and associated with one another in the early period after pediatric HCT. Future studies may elucidate the role of tachycardia and myocardial dysfunction early after HCT as important predictors of future cardiovascular dysfunction.

Cardiac Surveillance for Early Detection of Late Subclinical Cardiac Dysfunction in Childhood Cancer Survivors After Anthracycline Therapy

BACKGROUND

In childhood cancer survivors (CCSs) anthracycline-related cardiotoxicity is an important cause of morbidity and late mortality, but the optimal modality of cardiac surveillance still remains to be defined. The aim of this study was to assess whether non-invasive echocardiography-based functional cardiac measures can detect early subclinical myocardial changes in long-term pediatric cancer survivors who received anthracycline therapy.

METHODS

Twenty anthracycline-treated long-term CCSs and 20 age, sex, and body surface area matched healthy controls were enrolled in this study. Among cancer survivors, mean age at diagnosis was 6.5 ± 4.4 years, and the mean cumulative anthracycline dose was 234.5 ± 87.4 mg/m2. All subjects underwent a comprehensive functional echocardiographic protocol study including two-dimensional echocardiography (2D Echo), tissue Doppler imaging (TDI), speckle tracking (STE) and three-dimensional echocardiography (3D Echo). Patients were studied at a mean follow-up time of 6.5 ± 2.8 years from the end of therapy.

RESULTS

No significant differences in two-dimensional left ventricle ejection fraction (LVEF), diastolic parameters and speckle tracking (STE)-derived myocardial strain were observed between patients treated with anthracyclines and controls. Myocardial performance index was significantly prolonged (p = 0.005) and three-dimensional LVEF was significantly reduced (p = 0.002) in CCSs compared to controls, even though most values were within the normal range. There were no significant correlations between 2D, STE, and 3D echocardiographic parameters and age at diagnosis or duration of follow-up. No significant differences in echocardiographic parameters were found when stratifying cancer patients according to established risk factors for anthracycline cardiomyopathy.

CONCLUSIONS

This study found significantly reduced three-dimensional LVEF in CCSs compared with controls, despite no significant differences in two-dimensional LVEF and longitudinal strain values. These findings suggest that long-term CCSs who had received anthracycline therapy may be found to have subclinical features of myocardial dysfunction. However, further studies are needed to demonstrate the validity of new imaging techniques, including STE and 3D Echo, to identify patients at risk for cardiomyopathy in the long-term follow-up of CCSs.

Asymptomatic systolic dysfunction on contemporary echocardiography in anthracycline-treated long-term childhood cancer survivors: a systematic review

Purpose

Echocardiographic surveillance for asymptomatic left ventricular systolic dysfunction (ALVSD) is advised in childhood cancer survivors (CCS), because of their risk of heart failure after anthracycline treatment. ALVSD can be assessed with different echocardiographic parameters. We systematically reviewed the prevalence and risk factors of late ALVSD, as defined by contemporary and more traditional echocardiographic parameters.

Methods

We searched databases from 2001 to 2020 for studies on ≥ 100 asymptomatic 5-year CCS treated with anthracyclines, with or without radiotherapy involving the heart region. Outcomes of interest were prevalence of ALVSD—measured with volumetric methods (ejection fraction; LVEF), myocardial strain, or linear methods (fractional shortening; FS)—and its risk factors from multivariable analyses.

Results

Eleven included studies represented 3840 CCS. All studies had methodological limitations. An LVEF < 50% was observed in three studies in 1–6% of CCS, and reduced global longitudinal strain (GLS) was reported in three studies in 9–30% of CCS, both after a median follow-up of 9 to 23 years. GLS was abnormal in 20–28% of subjects with normal LVEF. Abnormal FS was reported in six studies in 0.3–30% of CCS, defined with various cut-off values (< 25 to < 30%), at a median follow-up of 10 to 18 years. Across echocardiographic parameters, reported risk factors were cumulative anthracycline dose and radiotherapy involving the heart region, with no ‘safe’ dose for ALVSD.

Conclusions

GLS identifies higher prevalence of ALVSD in anthracycline-treated CCS, than LVEF.

Implications for Cancer Survivors

The diagnostic and prognostic value of GLS should be evaluated within large cohorts.

Protocol registration

PROSPERO CRD42019126588

Supplementary Information

The online version contains supplementary material available at 10.1007/s11764-021-01028-4.

Refining the 10-Year Prediction of Left Ventricular Systolic Dysfunction in Long-Term Survivors of Childhood Cancer

Background

In childhood cancer survivors (CCS) at risk for heart failure, echocardiographic surveillance recommendations are currently based on anthracyclines and chest-directed radiotherapy dose. Whether the ejection fraction (EF) measured at an initial surveillance echocardiogram can refine these recommendations is unknown.

Objectives

The purpose of this study was to assess the added predictive value of EF at >5 years after cancer diagnosis to anthracyclines and chest-directed radiotherapy dose in CCS, for the development of left ventricular dysfunction with an ejection fraction <40% (LVD40).

Methods

Echocardiographic surveillance was performed in 299 CCS from the Emma Children’s Hospital in the Netherlands. Cox regression models were built including cardiotoxic cancer treatment exposures with and without EF to estimate the probability of LVD40 at 10-year follow-up. Calibration, discrimination, and reclassification were assessed. Results were externally validated in 218 CCS.

Results

Cumulative incidences of LVD40 at 10-year follow-up were 3.7% and 3.6% in the derivation and validation cohort, respectively. The addition of EF resulted in an integrated area under the curve increase from 0.74 to 0.87 in the derivation cohort and from 0.72 to 0.86 in the validation cohort (likelihood ratio p < 0.001). Reclassification of CCS without LVD40 improved significantly (noncase continuous net reclassification improvement 0.50; 95% confidence interval [CI]: 0.40 to 0.60). A predicted LVD40 probability ≤3%, representing 75% of the CCS, had a negative predictive value of 99% (95% CI: 98% to 100%) for LVD40 within 10 years. However, patients with midrange EF (40% to 49%) at initial screening had an incidence of LVD40 of 11% and a 7.81-fold (95% CI: 2.07- to 29.50-fold) increased risk of LV40 at follow-up.

Conclusions

In CCS, an initial surveillance EF, in addition to anthracyclines and chest-directed radiotherapy dose, improves the 10-year prediction for LVD40. Through this strategy, both the identification of low-risk survivors in whom the surveillance frequency may be reduced and a group of survivors at increased risk of LVD40 could be identified.

Diagnosis, Prevention, Treatment and Surveillance of Anthracycline-Induced Cardiovascular Toxicity in Pediatric Cancer Survivors

Advances in pediatric cancer therapies have dramatically improved the likelihood of survival. As survivors are aging, however, we are now understanding that treatment carries a significant risk of cardiovascular toxicity, which can develop immediately, or even many years after completing therapy. Anthracycline derivates are some of the most commonly used agents in pediatric oncology treatment protocols, which have a dose-dependent correlation with the development of cardiac toxicity. As we learn more about the mechanisms of toxicity, we are developing prevention strategies, including improvements in surveillance, to improve early diagnosis of heart disease. Current survivorship surveillance protocols often include screening echocardiograms to evaluate systolic function by measuring the ejection fraction or fractional shortening. However, these measurements alone are not enough to capture early myocardial changes. The use of additional imaging biomarkers, serum biomarkers, electrocardiograms, as well as cholesterol and blood pressure screening, are key to the early detection of cardiomyopathy and cardiovascular disease. Medical treatment strategies are the same as those used for heart failure from other causes, but earlier recognition and implementation can lead to improved long term outcomes.