Left ventricular diastolic function after anthracycline chemotherapy in childhood: relation with systolic function, symptoms, and pathophysiology

p38δ genetic ablation protects female mice from anthracycline cardiotoxicity

The efficacy of an anthracycline antibiotic doxorubicin (DOX) as a chemotherapeutic agent is limited by dose-dependent cardiotoxicity. DOX is associated with activation of intracellular stress signaling pathways including p38 MAPKs. While previous studies have implicated p38 MAPK signaling in DOX-induced cardiac injury, the roles of the individual p38 isoforms, specifically, of the alternative isoforms p38γ and p38δ, remain uncharacterized. We aimed to determine the potential cardioprotective effects of p38γ and p38δ genetic deletion in mice subjected to acute DOX treatment. Male and female wild-type (WT), p38γ-/-, p38δ-/-, and p38γ-/-δ-/- mice were injected with 30 mg/kg DOX and their survival was tracked for 10 days. During this period, cardiac function was assessed by echocardiography and electrocardiography and fibrosis by Picro Sirius Red staining. Immunoblotting was performed to assess the expression of signaling proteins and markers linked to autophagy. Significantly improved survival was observed in p38δ-/- female mice post-DOX relative to WT females, but not in p38γ-/- or p38γ-/-δ-/- male or female mice. The improved survival in DOX-treated p38δ-/- females was associated with decreased fibrosis, increased cardiac output and LV diameter relative to DOX-treated WT females, and similar to saline-treated controls. Structural and echocardiographic parameters were either unchanged or worsened in all other groups. Increased autophagy, as suggested by increased LC3-II level, and decreased mammalian target of rapamycin activation was also observed in DOX-treated p38δ-/- females. p38δ plays a crucial role in promoting DOX-induced cardiotoxicity in female mice by inhibiting autophagy. Therefore, p38δ targeting could be a potential cardioprotective strategy in anthracycline chemotherapy.NEW & NOTEWORTHY This study for the first time identifies the sex-specific roles of the alternative p38γ and p38δ MAPK isoforms in promoting doxorubicin (DOX) cardiotoxicity. We show that p38δ and p38γ/δ systemic deletion was cardioprotective in female but not in male mice. Cardiac structure and function were preserved in DOX-treated p38δ-/- females and autophagy marker was increased.

Brain Development and Heart Function after Systemic Single-Agent Chemotherapy in a Mouse Model of Childhood Leukemia Treatment

PURPOSE

Chemotherapy for childhood acute lymphoblastic leukemia (ALL) can cause late-appearing side effects in survivors that affect multiple organs, including the heart and brain. However, the complex ALL treatment regimen makes it difficult to isolate the causes of these side effects and impossible to separate the contributions of individual chemotherapy agents by clinical observation. Using a mouse model, we therefore assessed each of eight representative, systemically-administered ALL chemotherapy agents for their impact on postnatal brain development and heart function.

EXPERIMENTAL DESIGN

Mice were treated systemically with a single chemotherapy agent at an infant equivalent age, then allowed to age to early adulthood (9 weeks). Cardiac structure and function were assessed using in vivo high-frequency ultrasound, and brain anatomy was assessed using high-resolution volumetric ex vivo MRI. In addition, longitudinal in vivo MRI was used to determine the time course of developmental change after vincristine treatment.

RESULTS

Vincristine, doxorubicin, and methotrexate were observed to produce the greatest deficiencies in brain development as determined by volumes measured on MRI, whereas doxorubicin, methotrexate, and l-asparaginase altered heart structure or function. Longitudinal studies of vincristine revealed widespread volume loss immediately following treatment and impaired growth over time in several brain regions.

CONCLUSIONS

Multiple ALL chemotherapy agents can affect postnatal brain development or heart function. This study provides a ranking of agents based on potential toxicity, and thus highlights a subset likely to cause side effects in early adulthood for further study.

Myocardial stiffness as assessed by diastolic wall strain in adult survivors of childhood leukaemias with preserved left ventricular ejection fraction

Aims

We tested the hypothesis that myocardial stiffness as assessed by diastolic wall strain (DWS) is altered in adult survivors of childhood leukaemias with preserved left ventricular (LV) ejection fraction and explored its association with myocardial fibrosis and diastolic deformation.

Methods and results

Ninety-four (53 males) adult survivors of childhood leukaemias aged 22.2 ± 5.5 years and 66 (36 males) healthy controls were studied retrospectively. Diastolic wall strain and calibrated integrated backscatter (cIB) were measured as indices of myocardial stiffness and fibrosis, respectively. Left and right ventricular (RV) diastolic and torsional mechanics were interrogated using speckle tracking echocardiography. Patients had significantly lower LV DWS, and hence stiffer LV myocardium, and greater myocardial cIB in patients than controls (all P < 0.001). Left ventricular longitudinal, radial, and circumferential early diastolic strain rates, circumferential late diastolic strain rate, and peak twisting and untwisting velocities, tricuspid annular early diastolic velocity, and RV-free wall longitudinal early diastolic strain rate were significantly lower in patients than controls (all P < 0.05). Diastolic wall strain correlated inversely with myocardial cIB, and positively with LV longitudinal, radial, and circumferential early diastolic strain rates (all P < 0.05), while myocardial cIB correlated inversely with LV radial and circumferential early diastolic strain rates, circumferential late diastolic strain rate, peak twisting and untwisting velocities, and tricuspid annular e velocity (all P < 0.05).

Conclusion

In adult survivors of childhood leukaemias, despite the preservation of LV ejection fraction, increased stiffness of the LV myocardium is evident and is associated with myocardial fibrosis and impaired ventricular diastolic function.

Early change in left atrial function in patients treated with anthracyclines assessed by real-time three-dimensional echocardiography

Real-time three-dimensional echocardiography(RT-3DE) has allowed a better assessment of LA volumes and function. We sought to assess the early change in left atrial size and function in patients treated with anthracyclines using RT-3DE. 61 patients aged 44.9 ± 11.9 years with large B-cell non-Hodgkin lymphoma treated with doxorubicin were studied. Blood collection and echocardiography were performed at baseline and 1 day after completion of the chemotherapy. Global longitudinal strain (GLS), maximum, minimum and pre-atrial contraction LA volumes were measured and reservoir, conduit and booster pump function were assessed. Despite normal LVEF, passive emptying percent of total emptying (0.51 ± 0.14 vs. 0.40 ± 0.12, P < 0.001) and passive emptying index (0.29 ± 0.10 vs. 0.23 ± 0.06, P < 0.001) were remarkably reduced compared to baseline values, while active emptying percent of total emptying (0.49 ± 0.14 vs. 0.60 ± 0.12, P < 0.001) and active emptying index (0.41 ± 0.16 vs. 0.47 ± 0.16, P = 0.048) were increased. GLS (−21.64 ± 2.83 vs. −17.30 ± 2.50) was markedly reduced, cTnT levels was elevated from 0.005 ± 0.004 to 0.020 ± 0.026 ng/mL at the completion of chemotherapy (P all  < 0.001). Early LA functional change occur after doxorubicin exposure in patients with preserved LVEF, which could be detected by RT-3DE.

Doxorubicin induced heart failure: Phenotype and molecular mechanisms

Long term survival of childhood cancers is now more than 70%. Anthracyclines, including doxorubicin, are some of the most efficacious anticancer drugs available. However, its use as a chemotherapeutic agent is severely hindered by its dose-limiting toxicities. Most notably observed is cardiotoxicity, but other organ systems are also degraded by doxorubicin use. Despite the years of its use and the amount of information written about this drug, an understanding of its cellular mechanisms is not fully appreciated. The mechanisms by which doxorubicin induces cytotoxicity in target cancer cells have given insight about how the drug damages cardiomyocytes. The major mechanisms of doxorubicin actions are thought to be as an oxidant generator and as an inhibitor of topoisomerase 2. However, other signaling pathways are also invoked with significant consequences for the cardiomyocyte. Further the interaction between oxidant generation and topoisomerase function has only recently been appreciated and the consequences of this interaction are still not fully understood. The unfortunate consequences of doxorubicin within cardiomyocytes have promoted the search for new drugs and methods that can prevent or reverse the damage caused to the heart after treatment in cancer patients. Alternative protocols have lessened the impact on newly diagnosed cancer patients. However the years of doxorubicin use have generated a need for monitoring the onset of cardiotoxicity as well as understanding its potential long-term consequences. Although a fairly clear understanding of the short-term pathologic mechanisms of doxorubicin actions has been achieved, the long-term mechanisms of doxorubicin induced heart failure remain to be carefully delineated.

Echocardiographic evaluation of the early cardiotoxic effect of hematopoietic stem cell transplantation in patients with hematologic malignancies

The purpose was to evaluate the early cardiotoxic effects of the treatment in the course of hematopoietic stem cell transplantation (HSCT) in patients with hematologic malignancies. The studies were conducted on 47 patients qualified for the HSCT. Echocardiography was carried out prior to the HSCT and after the HSCT. It was shown that higher age, administration of cyclophosphamide and higher glucose concentrations represented independent risk factors for the worsening of left ventricular diastolic function. Higher cumulative dose of anthracyclines in the previous cytostatic treatment, higher age and administration of cyclophosphamide represented independent risk factors for worsening of left ventricular systolic function. Peri-transplant therapy in the course of HSCT in patients with hematologic malignancies gives the negative effect on the diastolic and systolic left ventricular function, however, previous treatment is of importance, as higher cumulative dose of anthracyclines represents an independent risk factor for the worsening of left ventricular systolic function.

Clinical Characteristics and Treatment of Cardiomyopathies in Children

Cardiomyopathies are diseases of the heart muscle, a term introduced in 1957 to identify a group of myocardial diseases not attributable to coronary artery disease. The definition has since been modified to refer to structural and or functional abnormalities of the myocardium where other known causes of myocardial dysfunction, such as systemic hypertension, valvular disease and ischemic heart disease, have been excluded. In this review, we discuss the pathophysiology, clinical assessment and therapeutic strategies for hypertrophic, dilated and hypertrophic cardiomyopathies, with a particular focus on aspects unique to children.

Etiological Peculiarities in Pediatric Heart Failure

Heart failure in children presents important characteristic features different from adult congestive failure, from a pathophysiological and mostly from an etiopathogenic point of view. Heart failure in children is, in most cases, a consequence of congenital structural cardiac abnormalities that remained unoperated, underwent a palliative operation or presented post-surgery complications, or of cardiomyopathy. Based on the nature of the clinical presentation, new onset heart failure can be differentiated from transient heart failure and chronic heart failure. Chronic heart failure may occur in children with biventricular circulation (systolic or diastolic dysfunction), in cardiac structural abnormalities with a right systemic ventricle and in the so-called univentricular heart. Acute heart failure can appear as acute heart failure at onset or as an aggravation of heart failure on the background of acute decompensated chronic heart failure.

Multimodality Imaging in Cardiooncology

Cardiotoxicity represents a rising problem influencing prognosis and quality of life of chemotherapy-treated patients. Anthracyclines and trastuzumab are the drugs most commonly associated with development of a cardiotoxic effect. Heart failure, myocardial ischemia, hypertension, myocarditis, and thrombosis are typical manifestation of cardiotoxicity by chemotherapeutic agents. Diagnosis and monitoring of cardiac side-effects of cancer treatment is of paramount importance. Echocardiography and nuclear medicine methods are widely used in clinical practice and left ventricular ejection fraction is the most important parameter to asses myocardial damage secondary to chemotherapy. However, left ventricular ejection decrease is a delayed phenomenon, occurring after a long stage of silent myocardial damage that classic imaging methods are not able to detect. New imaging techniques including three-dimensional echocardiography, speckle tracking echocardiography, and cardiac magnetic resonance have demonstrated high sensitivity in detecting the earliest alteration of left ventricular function associated with future development of chemotherapy-induced cardiomyopathy. Early diagnosis of cardiac involvement in cancer patients can allow for timely and adequate treatment management and the introduction of cardioprotective strategies.

NT-proBNP as early marker of subclinical late cardiotoxicity after doxorubicin therapy and mediastinal irradiation in childhood cancer survivors

Background. Childhood cancer survivors treated with anthracyclines and mediastinal irradiation are at risk for late onset cardiotoxicity. Aims of the Study. To assess the role of N-terminal pro-brain natriuretic peptide (NT-proBNP) and tissue Doppler imaging (TDI) as early predictors of late onset cardiotoxicity in asymptomatic survivors of childhood cancer treated with doxorubicin with or without mediastinal irradiation. Methods. A cross-sectional study on 58 asymptomatic survivors of childhood cancer who received doxorubicin in their treatment protocols and 32 asymptomatic Hodgkin's lymphoma survivors who received anthracycline and mediastinal irradiation. Levels of NT-proBNP, TDI, and conventional echocardiography were determined. Results. Thirty percent of survivors had abnormal NT-proBNP levels. It was significantly related to age at diagnosis, duration of follow-up, and cumulative dose of doxorubicin. TDI detected myocardial affection in 20% more than conventional echocardiography. Furthermore, abnormalities in TDI and NT-pro-BNP levels were more common in Hodgkin lymphoma survivors receiving both chemotherapy and radiotherapy. Conclusions. TDI could detect early cardiac dysfunction even in those with normal conventional echocardiography. Measurement of NT-proBNP represents an interesting strategy for detecting subclinical cardiotoxicity. We recommend prospective and multicenter studies to validate the role of NT-proBNP as an early marker for late onset doxorubicin-induced cardiotoxicity.

Early left ventricular dysfunction in children after hematopoietic stem cell transplantation for acute leukemia: a case control study using speckle tracking echocardiography

Background and Objectives

Cardiovascular complications are the leading cause of morbidity and mortality in childhood cancer survivors. Hematopoietic stem cell transplantation (HSCT) is a curable therapy for pediatric cancer. However, changes in cardiac function in children after HSCT are not well known. We assessed left ventricular (LV) function in children after HSCT using speckle tracking echocardiography (STE).

Subjects and Methods

Forty consecutive patients with median age of 11.9 years (range, 1.5-16 years) who received HSCT for acute leukemia and had comprehensive echocardiography before and after (median 9.2 month) HSCT were included in this study. The LV function parameters including conventional tissue Doppler imaging (TDI) and STE data were collected from pre- and post-HSCT echocardiography. These data were compared to those of 39 age-matched normal controls.

Results

Compared to normal controls, post HSCT patients had similar (p=0.06) LV ejection fraction. However, the following three LV function parameters were significantly decreased in post HSCT patients: rate-corrected velocity of circumferential fiber shortening (p=0.04), mitral inflow E velocity (p<0.001), and mitral septal annular E' velocity (p=0.03). The following four STE parameters were also significantly decreased in post HSCT patients: LV global circumferential systolic strain (p<0.01), strain rate (SR, p=0.01), circumferential diastolic SR (p<0.01), and longitudinal diastolic SR (p<0.001). There was no significant change in TDI or STE parameters after HSCT compared to pre-HSCT. Patients with anthracycline cumulative dose >400 mg/m² showed significantly (p<0.05) lower circumferential systolic strain and circumferential diastolic SR.

Conclusion

Subclinical cardiac dysfunction is evident in children after HSCT. It might be associated with pre-HSCT anthracycline exposure with little effect of conditioning regimens. Serial monitoring of cardiac function is mandatory for all children following HSCT.

Survivorship

Significant therapeutic advances for soft tissue sarcomas allow increasing numbers of patients--adult and pediatric--to achieve long term survival. However, the harsh cytotoxic therapies are responsible for adverse physical and psychosocial effects that require long-term follow-up care, specific to survivorship issues. In the adult and pediatric patient population, guidelines for care developed by experts in comprehensive survivorship clinics are evolving to assist the practitioner while on-line supports bring information directly to the survivors.

Cardiomyopathy associated with cancer therapy

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

Cardiotoxicity and oncological treatments

BACKGROUND

Cardiotoxic and other side effects limit the usefulness of treatments for cancer.

METHOD

This article is based on pertinent articles that were retrieved by a selective search in PubMed and other databases, and on the guidelines of the European Society of Cardiology, the Association of Scientific Medical Societies in Germany, and the European Society of Medical Oncology.

RESULTS

Prospective studies have shown that some treatments for cancer are cardiotoxic. The heart damage that they cause can manifest itself as arrhythmia, arterial hypertension, thromboembolism, angina pectoris, myocardial infarction, or heart failure. It has been observed that potentially lethal complications can arise as late as 40 years after treatment of the original cancer. The anthracycline drug doxorubicin, given in a dose of 500 mg/m2 of body surface area, has been found to cause cardiac complications in 4-36% of the patients treated with it. Trastuzumab and epirubicin cause dose-limiting cardiac events in 1.7-5% of patients, depending on the dosage. Paclitaxel causes bradycardia, intracardiac conduction block, or arrhythmia in 0.5% of patients. 18% of patients treated with sunitimib or sorafenib have clinical manifestations relating to the heart (angina pectoris, dyspnea). 5-fluorouracil can cause angina pectoris at the beginning of treatment and rarely causes myocardial infarction. Cardiac radiation therapy, a form of treatment practiced in earlier decades, can cause cardiac complications 20 years after the event. The opportunity to prevent cardiac complications of anthracycline drugs with dexrazoxane is decidedly limited, but initial studies have shown that treatment with beta-blockers and ACE inhibitors lessens the likelihood of cardiotoxic side effects. When cardiac complications arise, the generally applicable rules for the treatment of each type of cardiac problem should be followed. The oncological treatment protocol should be adjusted or switched to one that is less damaging to the heart.

CONCLUSION

Treating physicians need to be thoroughly acquainted with the cardiotoxic effects of anti-cancer drugs so that they can diagnose them early on and avoid jeopardizing the overall success of treatment.

Toward functional screening of cardioactive and cardiotoxic drugs with zebrafish in vivo using pseudodynamic three-dimensional imaging

Given the high mortality in patients with cardiovascular diseases and the life-threatening consequences of drugs with unforeseen adverse effects on hearts, a critical evaluation of the pharmacological response of cardiovascular function on model animals is important especially in the early stages of drug development. We report a proof-of-principle study to demonstrate the utility of zebrafish as an analytical platform to predict the cardiac response of new drugs or chemicals on human beings. With pseudodynamic 3D imaging, we derive individual parameters that are central to the cardiac function of zebrafish, including the ventricular stroke volume, ejection fraction, cardiac output, heart rate, diastolic filling function, and ventricular mass. We evaluate both inotropic and chronotropic responses of the heart of zebrafish treated with drugs that are commonly prescribed and possess varied known cardiac activities. We reveal deranged cardiac function of a zebrafish model of cardiomyopathy induced with a cardiotoxic drug. The cardiac function of zebrafish exhibits a pharmacological response similar to that of human beings. We compare also cardiac parameters obtained in this work with those derived with conventional 2D approximation and show that the latter tends to overestimate the cardiac parameters and produces results of greater variation. In view of the growing interest of using zebrafish in both fundamental and translational biomedical research, we envisage that our approach should benefit not only contemporary pharmaceutical development but also exploratory research such as gene, stem cell, or regenerative therapies targeting congenital or acquired heart diseases.

Anthracycline-induced cardiotoxicity: prospective cohort study from Pakistan

OBJECTIVES

To identify anthracycline-induced acute (within 1 month) and early-onset chronic progressive (within 1 year) cardiotoxicity in children younger than 16 years of age with childhood malignancies at a tertiary care centre of Pakistan.

DESIGN

Prospective cohort study.

SETTING

Aga Khan University, Karachi, Pakistan.

PARTICIPANTS

110 children (aged 1 month-16 years).

INTERVENTION

Anthracycline (doxorubicin and/or daunorubicin).

OUTCOME MEASUREMENTS

All children who received anthracycline as chemotherapy and three echocardiographic evaluations (baseline, 1 month and 1 year) between July 2010 and June 2012 were prospectively analysed for cardiac dysfunction. Statistical analysis including systolic and diastolic functions at baseline, 1 month and 1 year was carried out by repeated measures analysis of variance.

RESULTS

Mean age was 74±44 months and 75 (68.2%) were males. Acute lymphoblastic leukaemia was seen in 70 (64%) patients. Doxorubicin alone was used in 59 (54%) and combination therapy was used in 35 (32%). A cumulative dose of anthracycline <300 mg/m(2) was used in 95 (86%). Fifteen (14%) children developed cardiac dysfunction within a month and 28 (25%) children within a year. Of these 10/15 (66.6%) and 12/28 (43%) had isolated diastolic dysfunction, respectively, while 5/15 (33.3%) and 16/28 (57%) had combined systolic and diastolic dysfunction. Seven (6.4%) patients expired due to severe cardiac dysfunction. Eight of 59 (13.5%) children showed dose-related cardiotoxicity (p=<0.001). Cardiotoxicity was also high when the combination of doxorubicin and daunorubicin was used (p=0.004).

CONCLUSIONS

Incidence of anthracycline-induced cardiotoxicity is high. Long-term follow-up is essential to diagnose its late manifestations.

Imaging of early modification in cardiomyopathy: the doxorubicin-induced model

Doxorubicin chemotherapy is effective and widely used to treat acute lymphoblastic leukemia. However, its effectiveness is hampered by a wide spectrum of dose-dependent cardiotoxicity including both morphological and functional changes, affecting primarily the myocardium. Non-invasive imaging techniques are used for the diagnosis and monitoring of these cardiotoxic effects. The purpose of this review is to summarize and compare the most common imaging techniques used in early detection and therapeutic monitoring of doxorubicin-induced cardiotoxicity and the suggested mechanisms of such side effects. Imaging techniques using echocardiography including conventional 2D and 3D echocardiography along with MRI sequences including Tagging, Cine, and quantitative MRI in detecting early myocardial damage are also reviewed. As there is a multitude of reported indices and imaging methods to assess particular functional alterations, we limit this review to the most relevant techniques based on their clinical application and their potential to early detection of doxorubicin-induced cardiotoxic effects.

New three-dimensional speckle-tracking echocardiography identifies global impairment of left ventricular mechanics with a high sensitivity in childhood cancer survivors

BACKGROUND

The aim of this case-control study was to assess the usefulness of three-dimensional (3D) speckle-tracking echocardiography in the evaluation of global left ventricular (LV) myocardial performance in adolescent and adult survivors of childhood cancers.

METHODS

Fifty-three anthracycline-treated survivors of childhood cancers (mean age, 18.6 ± 5.1 years) and 38 controls were studied. Three-dimensional speckle-tracking echocardiography was performed to assess LV 3D global and segmental strain, time to peak segmental 3D strain, LV torsion, and ejection fraction. LV systolic dyssynchrony index (SDI) was calculated as the percentage of the standard deviation of times to peak strain of the 16 segments divided by the RR interval. A global performance index (GPI) was calculated as (global 3D strain × torsion)/SDI. The area under the receiver operating characteristic curve was calculated to determine the capability of various echocardiographic indices to discriminate between patients and controls.

RESULTS

Compared with controls, patients had significantly reduced LV global 3D strain (P < .001), torsion (P < .001), and GPI (P < .001) and greater SDI (P < .001). All except the basal anteroseptal segment in patients had reduced regional 3D strain compared with controls (P < .05 for all). Global 3D strain (P = .018), SDI (P = .003), and GPI (P = .02) were correlated with cumulative anthracycline dose. The areas under the curves for GPI, global 3D strain, 1/SDI, torsion, and ejection fraction were 0.92, 0.79, 0.79, 0.79, and 0.78, respectively. A GPI cutoff of 10.6°/cm had sensitivity of 84.9% and specificity of 81.6% of differentiating patients from controls.

CONCLUSIONS

Three-dimensional speckle-tracking echocardiography enables the derivation of an index of LV global performance that incorporates LV 3D strain, dyssynchrony, and torsion for the sensitive detection of altered LV mechanics in childhood cancer survivors.

Effect of bone marrow transplantation on diastolic function indices

INTRODUCTION

High-dose chemotherapy and bone marrow transplantation result in direct and indirect changes in cardiac function. the finding suggests a decreased left ventricular diastolic compliance after high-dose cyclophosphamide treatment, but the effects of bone marrow transplantation (BMT) on cardiac diastolic function are less studied. We aimed to evaluate changes before and after the procedure in cardiac diastolic function in patients undergoing BMT.

DESIGN AND METHODS

We designed this study to evaluate the effects of BMT on diastolic cardiac function. Patients with lymphoma (Hodgkin's and non-Hodgkin's), multiple myeloma, and solid tumors who were candidates for autologous BMT were selected for the study. The patients underwent a cardiac consultation and echocardiography before their admission for BMT. E-wave velocity and time to relaxation by tissue Doppler echocardiography in the septal, lateral, anterior, inferior, anteroseptal, and posterior wall; and the E-wave velocity of the right ventricle (RV) were measured before and after BMT.

RESULT

Thirty patients fulfilled our inclusion criteria and entered the study. The mean diastolic function measures were calculated before and after BMT. E-wave velocity in the septal, lateral, anterior, inferior, anteroseptal and posterior walls after transplantation decreased by 19.2% (p=0.008), 14.5% (p=0.008), 22.19% (p=0.3), 18.9% (p<0.001), 21.9% (p=0.01), and 7.5% (p=0.01), respectively. The time to relaxation decreased by 13.5%, 13.7%, 12.4%, 11.4%, 11.1%, and 13.1%, respectively, after transplantation (p<0.001). E-wave velocity of RV decreased 15.6% after BMT (p=0.02).

CONCLUSION

Data regarding alterations in diastolic functioning after BMT are scarce. This study suggests that diastolic function alters after BMT.

Use of cardiac markers for monitoring of doxorubixin-induced cardiotoxicity in children with cancer

The aim of this study was to evaluate N-terminal probrain natriuretic peptides (NT-pro-BNP), cardiac troponin T, and creatinine kinase, MB isoenzyme (CK-MB) in the determination of subclinical left ventricular (LV) dysfunction by echocardiography in patients treated with doxorubicin. We performed a cross-sectional case study of systolic, diastolic function and tissue Doppler imaging by echocardiography in children with cancer who received a certain cumulative dose of doxorubicin. Blood levels for NT-pro-BNP, cardiac troponin T, and CK-MB were analyzed within 6 hours of the cardiac study. Of 30 patients, 5 (16.7%) had LV dysfunction with an abnormally high NT-pro-BNP level of 363 ± 78 pg/mL, whereas patients with normal LV function had an NT-pro-BNP level of 148 ± 173 pg/mL (P = 0.012). The NT-pro-BNP level not only inversely correlated with fractional shortening (r = -0.43, P = 0.017) and ejection fraction (r = - 0.45, P = 0.013) but also correlated with mitral deceleration time ( r = 0.41, P = 0.021) and a cumulative dose of doxorubicin (r = 0.44, P = 0.014). For tissue Doppler imaging, NT-pro-BNP correlated with a peak systolic velocity at the myocardial segment (Sm) (r = -0.40, P = 0.027). NT-pro-BNP is a sensitive test and has a moderate relationship with the LV systolic and diastolic function, thus making it a useful cardiac marker for the monitoring of early anthracycline cardiotoxicity.

Role of echocardiography in cancer care

For cancer therapy survivors, regular echocardiographic follow-up of left ventricular function is considered part of standard care. Metastases of tumors on the pericardium and myocardium as well as cardiac structure and function can be assessed using echocardiography. This review focuses on current and developing echocardiographic modalities for the assessment of cardiac structure and function in the cancer patient, delineates the echocardiographic diagnosis of cardiac amyloidosis, and discusses the echocardiographic features of cardiac masses including those associated with the hypercoagulable state of cancer.

Long-term cardiac follow-up of children treated with anthracycline doses of 300 mg/m2 or less for acute lymphoblastic leukemia

BACKGROUND

The cardiotoxic effect of anthracyclines has been well described for moderate to high cumulative doses (>350 mg/m(2)). However, the question of whether sub-clinical signs of cardiomyopathy may develop and progress over time in children receiving doses of <350 mg/m(2) is controversial. The aim of the present study was to examine cardiac function with serial echocardiography from diagnosis to last follow-up, relapse, or death, and to investigate whether suspected risk factors (e.g., age at diagnosis, gender, cumulative dose, and length of follow-up) had a significant influence on cardiac function.

PROCEDURE

An unselected cohort of 80 patients treated with multi-drug chemotherapy including anthracycline doses of 300 mg/m(2) or less for childhood acute lymphoblastic leukemia was followed with serial echocardiograms. The deviations of each echocardiogram from normal values for the same age and body-surface areas were calculated. The influences of risk factors were analyzed using univariate and multivariate regression. Lowess curves of time dependence were calculated.

RESULTS

All echocardiographic parameters including ejection fraction (EF) deteriorated significantly over time. Male gender was significantly associated with systolic dilatation of the left ventricle and positively associated with left ventricular mass. Reduction of EF was significantly associated with age at diagnosis and male gender.

CONCLUSIONS

Anthracycline doses of <300 mg/m(2) may contribute to a decline in cardiac function over time. Although the deterioration in cardiac parameters was not associated with clinical symptoms, life-long cardiac surveillance for these patients is important to establish the impact of low-dose anthracycline therapy on long-term cardiac health.

Tissue and flow myocardial performance index measurements taken during dobutamine stress echocardiography for early diagnosis of late anthracycline cardiotoxicity

The purpose of this study was to define the role of tissue and flow myocardial performance index (MPI) measured during dobutamine stress and tissue Doppler echocardiography in the early diagnosis of late cardiotoxicity among patients with childhood cancer treated with anthracycline. The study included 20 patients (14 male and 6 female; mean age 18.4 +/- 3.2 years) as the study group and 18 healthy volunteers (14 female and 4 male, mean age: 19.2 +/- 4.0) as the control group. The mean cumulative dose of anthracycline treatment was 282.1 +/- 125.9 mg/m2, and the mean time period after the last dose of anthracycline was 10.2 +/- 4.0 years. Echocardiography was performed during rest and at infusions of 5, 10, 15, and 20 micro/kg/min dobutamine. Although only isovolumetric relaxation and contraction times of the patient group were prolonged at rest, dobutamine infusion showed significant differences in % left ventricle (LV) posterior wall thickening, LV end-systolic wall stress, LV diastolic and systolic diameter, mitral acceleration, and deceleration time in the patient group compared with the control group. Tissue and flow MPI of the LV, tissue MPI of the right ventricle (RV), and interventricular septum of the patient group were higher than the control group throughout the test. LV tissue MPI increased much more than LV flow MPI when stress was increased. In conclusion, LV tissue MPI value during stress is more valuable than LV flow MPI in the early diagnosis of late cardiotoxicity. RV function can be assessed by tissue Doppler MPI.

Cardiac troponin T for early detection of cardiotoxicity in breast cancer patients treated with epirubicin

The aim of the study was to investigate the role of cTnT for the prediction of long term cardiac dysfunction after epirubicin-containing adjuvant chemotherapy for breast cancer. The study group comprised of 45 patients (all female; mean age 48 ±8 years), treated with epirubicin-containing adjuvant chemotherapy for stage 2 and stage 3 breast cancer. Patients received either 4 cycles of cyclophosphamide plus epirubicin (90 mg/m2) (n=23; stage 2 breast cancer) or 6 cycles of cyclophosphamide plus epirubicin (75 mg/m2) plus fluorouracil (n=18; stage 3 breast cancer). Venous blood samples were drawn, before and 72 hours after, every cycle of chemotherapy for the measurement of cTnT. Cardiac assessment was carried out at baseline and 1 year after chemotherapy by clinical evaluation, electrocardiography, radio-nuclide ventriculography (RNV) and transthoracic echocardiography. All patients remained free of clinical heart failure during the study period. In 26 patients (63%), cTnT was elevated after chemotherapy. Mean left ventricular ejection fraction, assessed by RNV at baseline and one year after chemotherapy, were 61±8% and 56±7% (p<0.0001). The sensitivity and specifity of cTnT for the detection of left ventricular systolic dysfunction at one year were 69% and 39% respectively. Echocardiographic examinations at baseline and one year after chemotherapy revealed a significant decrease in E/A ratio from 1.15±0.3 to 0.9±0.2 in cTnT positive patients, suggesting diastolic dysfunction. In conclusion, elevated serum cTnT levels after epirubicin-containing adjuvant chemotherapy for stage 2 and stage 3 breast cancer, predict future cardiac dysfunction with moderate sensitivity and poor specificity.

Perception of effort at low and moderate intensity exercise in survivors of childhood acute lymphoblastic leukaemia

OBJECTIVE

The study examined the degree to which male and female survivors of acute lymphoblastic leukaemia (ALL) perceive effort at low and moderate intensity exercise in association with related physiological variables.

MATERIALS AND METHODS

Participants were 67 children. Thirty-five (14 boys and 21 girls) were long-time survivors of ALL and 32 (18 boys and 14 girls) were control subjects. The Children's Effort Rating Table (CERT) was used to measure whole-body perceived exertion at low and moderate intensity exercise. Peak oxygen uptake was measured using a motorized treadmill. CERT and physiological data were analysed using 2 x 2 mixed analyses of variance, appropriate t-tests and coefficients of correlation.

RESULTS

In absolute terms, boys treated for ALL found perception of effort to be more strenuous at both low (3.9 vs. 3.5 units) and moderate (6.1 vs. 5.3 units) intensity exercise than control subjects, although differences were not significant (p > 0.05); girls treated for ALL found perception of effort to be the same as controls at low intensity exercise (3.1 vs. 3.1 units) but slightly higher than controls at moderate intensity exercise (5.6 vs. 5.2 units); neither of these differences were significant (p > 0.05). When CERT values were adjusted for (.-)VO(2) peak (%) and heart rate (HR) peak (%) differences remained non-significant. There were no significant interactions (Intensity x Group) in males, but the interaction for (.-)VO(2) peak (%) was significant in females (p < 0.05). The main effect for Intensity (low and moderate) was significant for all variables in boys and girls (p < 0.0001). The main effect for Group (ALL and controls) identified significantly greater absolute (b.p.m.) and relative (%) HR values in ALL boys at low and moderate intensity exercise. In female ALL and control subjects the interaction (Intensity x Group) distinguished between (.-)VO(2) peak (%) at moderate intensity exercise and HR peak (%) at low and moderate intensity exercise. Coefficients of correlation between perceived effort and (.-)VO(2) peak (%) in boys and girls were low to high (0.28-0.76), and between absolute and relative HR were also low to high (0.33-0.73). There were low correlations between time 'off therapy' and perceived effort, (.-)VO(2) peak (%) and HR peak (%) (-0.003 to -0.49).

CONCLUSION

It was concluded that perception of effort in survivors of ALL at low and moderate intensity exercise was the same as that of control subjects. Correlations between perceived effort and physiological variables at moderate exercise were low to high, while those between perceived effort and time from treatment were generally weak.

A risk-adapted, response-based approach using ABVE-PC for children and adolescents with intermediate- and high-risk Hodgkin lymphoma: the results of P9425

Current treatment strategies for Hodgkin lymphoma result in excellent survival but often confer significant long-term toxicity. We designed ABVE-PC (doxorubicin, bleomycin, vincristine, etoposide, prednisone, cyclophosphamide) to (1) enhance treatment efficacy by dose-dense drug delivery and (2) reduce risk of long-term sequelae by response-based reduction of cumulative chemotherapy. Efficient induction of early response by dose-dense drug delivery supported an early-response-adapted therapeutic paradigm. The 216 eligible patients were younger than 22 years with intermediate- or high-risk Hodgkin lymphoma. ABVE-PC was administered every 21 days. Rapid early responders (RERs) to 3 ABVE-PC cycles received 21 Gy radiation to involved regions; RER was documented in 63% of patients. Slow early responders received 2 additional ABVE-PC cycles before 21 Gy radiation. Five-year event-free-survival was 84%: 86% for the RER and 83% for the slow early responders (P = .85). Only 1% of patients had progressive disease. Five-year overall survival was 95%. With this regimen, cumulative doses of alkylators, anthracyclines, and epipodophyllotoxins are below thresholds usually associated with significant long-term toxicity. ABVE-PC is a dose-dense regimen that provides outstanding event-free survival/overall survival with short duration, early-response-adapted therapy.

Left ventricular systolic and diastolic function after anthracycline chemotherapy in childhood

BACKGROUND

In childhood, late cardiotoxicity is characterized by inappropriately thin wall and consequent increased end-systolic wall stress, but the associations of impaired left ventricular geometry and function occurring under these circumstances need further investigation.

HYPOTHESIS

The purpose of this study was to assess anthracycline late effects on the relationships occurring between increased end-systolic stress (ESS) and changes in both M-mode systolic measurements (i.e., endocardial and midwall fractional shortening) and Doppler diastolic indices in the pediatric age.

METHODS

The population consisted of 101 children treated with anthracyclines for at least 12 months and 91 healthy children. Using M-mode echocardiography, end-systolic wall stress was calculated as index of afterload, and endocardial and midwall fractional shortening as systolic indices. Doppler transmitral measurements were made as diastolic indices.

RESULTS

Patients treated with anthracyclines showed significantly lower relative wall thickness and left ventricular mass index, greater end-systolic wall stress, reduced endocardial and midwall fractional shortening and peak E/A ratio, prolonged deceleration, and isovolumic relaxation times. Direct relationships were found between end-systolic wall stress and both endocardial and midwall shortening. The use of midwall shortening in the relation showed a greater, but not significant increase (from 3 to 6%) in the proportion of patients with depressed systolic function than did endocardial shortening. In the anthracycline group, end-systolic wall stress was also inversely related to relative wall thickness and directly to isovolumic relaxation time.

CONCLUSIONS

In childhood, reduced myocardial thickness and increased afterload explain much of systolic and diastolic dysfunction of late anthracycline toxicity. Midwall fractional shortening does not seem to add useful information for identifying subsets of children more prone to the development of heart failure.

Anthracycline cardiotoxicity in childhood

Over the last 40 years, a significant advance has been made in the treatment of childhood and adult cancers. However, the increase of the survival rate points out medium- and long-term adverse effects that constitute a serious limitation for the quality of life in adults survived from a childhood cancer. Cardiovascular disease is an important cause of morbidity and mortality in adults treated with chemo- and radiotherapy for childhood cancers. Although some antitumor treatments are potentially cardiotoxic, anthracycline therapy and radiotherapy are mostly responsible for long-term cardiac damage. Anthracycline toxicity is generally limited to the myocardium, while radiation can cause injury to all components of the heart. The purpose of this review is to discuss the mechanisms of action of anthracyclines, their cardiotoxicity, the feasibility of screening, and the prevention of cardiac damage after treatment in childhood.

Cardiac damage after treatment of childhood cancer: a long-term follow-up

BACKGROUND

With improved childhood cancer cure rate, long term sequelae are becoming an important factor of quality of life. Signs of cardiovascular disease are frequently found in long term survivors of cancer. Cardiac damage may be related to irradiation and chemotherapy.We have evaluated simultaneous influence of a series of independent variables on the late cardiac damage in childhood cancer survivors in Slovenia and identified groups at the highest risk.

METHODS

211 long-term survivors of different childhood cancers, at least five years after treatment were included in the study. The evaluation included history, physical examination, electrocardiograpy, exercise testing and echocardiograpy. For analysis of risk factors, beside univariate analysis, multivariate classification tree analysis statistical method was used.

RESULTS AND CONCLUSION

Patients treated latest, from 1989-98 are at highest risk for any injury to the heart (73%). Among those treated earlier are at the highest risk those with Hodgkin's disease treated with irradiation above 30 Gy and those treated for sarcoma. Among specific forms of injury, patients treated with radiation to the heart area are at highest risk of injury to the valves. Patients treated with large doses of anthracyclines or concomitantly with anthracyclines and alkylating agents are at highest risk of systolic function defect and enlarged heart chambers. Those treated with anthracyclines are at highest risk of diastolic function defect. The time period of the patient's treatment is emerged as an important risk factor for injury of the heart.

Extracardiac medical and neuromuscular implications in restrictive cardiomyopathy

Restrictive cardiomyopathy (RCMP) is characterized by restrictive filling and reduced diastolic volume of either or both ventricles with normal or near-normal systolic function and wall thickness. It may occur idiopathically or as a cardiac manifestation of systemic diseases such as scleroderma, amyloidosis, Churg-Strauss syndrome, cystinosis, sarcoidosis, lymphoma, Gaucher's disease, hemochromatosis, Fabry's disease, pseudoxanthoma elasticum, hypereosinophilic syndrome, carcinoid, Noonan's syndrome, reactive arthritis, or Werner's syndrome and various neuromuscular disorders. Whereas in idiopathic RCMP the therapeutic options are only treatment of cardiac congestion, in cases with an underlying disorder, a causal therapy may be available. Patients with RCMP should be investigated as soon as the cardiac diagnosis is established for extracardiac diseases to detect a possibly treatable cause of RCMP before the disease becomes intractable. These investigations include a diligent clinical history and examination, blood tests, and ophthalmologic, otologic, dermatologic, gastroenterologic, nephrologic, hematologic, and neurologic examinations. If extracardiac examinations do not reveal a plausible cause for RCMP, endomyocardial biopsy is indicated.

Late echocardiography assessment of systolic and diastolic function of the left ventricle in pediatric cancer survivors after anthracycline therapy

BACKGROUND

The usefulness of daunorubicin (DAUNO) and doxorubicin, members of the anthracycline class of anticancer drugs, is limited by their cardiotoxicity. The purpose of our echocardiographic study was to assess the left ventricular (LV) function in long-term pediatric cancer survivors who had received DAUNO and dox as part of their therapy.

PATIENTS AND METHODS

Seventy patients and 70 age, sex, and body surface area matched healthy controls were evaluated. Among the patients, the mean cumulative anthracycline dose was 321.6 (range, 150 to 868 mg/m); the mean interval from cancer diagnosis to evaluation was 13.9 years (range, 7 to 30 y).

RESULTS

Fifteen of the 70 (21.4%) patients had a reduced ejection fraction (EF). Compared with the healthy controls, the mean EF and E/A were decreased to low normal levels in the patients, whereas deceleration time and isovolumetric relaxation time were prolonged. The E/A and deceleration time were significantly different for the females but not the males. The Tissue Doppler Index was normal but the Myocardial Performance Index was prolonged and correlated with EF (r=-0.499, P<0.001). There was a correlation between EF with cumulative anthracycline dose (r=-0.306; P=0.010) and time off therapy (r=-0.281; P=0.019). Diastolic indices suggested a tendency toward abnormal LV relaxation. Myocardial Performance Index seems to be a good index for monitoring LV status, because it was prolonged as EF decreased.

CONCLUSIONS

This study suggests that long-term survivors who received doxorubicin and DAUNO may be found to have subclinical features of myocardial dysfunction when evaluated years after the completion of therapy.

American Society of Clinical Oncology clinical evidence review on the ongoing care of adult cancer survivors: cardiac and pulmonary late effects

PURPOSE

To review the evidence on the incidence of long-term cardiac or pulmonary toxicity secondary to chemotherapy, radiotherapy, or trastuzumab in symptomatic and asymptomatic cancer survivors.

METHODS

An American Society of Clinical Oncology Panel reviewed pertinent information from the literature through February 2006.

RESULTS

Few studies directly addressing the benefits of screening for long-term cardiac or pulmonary toxicity in asymptomatic cancer survivors who received chemotherapy, radiotherapy, or trastuzumab were identified. The reviewed literature included primarily retrospective and cross-sectional studies describing the incidence of cardiac and pulmonary late effects. Anatomic and/or functional abnormalities have been associated with use of all currently available anthracyclines and their derivatives. Trastuzumab-related cardiac dysfunction rarely causes death, and in most cases is reversible with improvement in cardiac function on drug discontinuation and/or treatment with cardiac medications. The estimated aggregate incidence of radiation-induced cardiac disease is 10% to 30% by 5 to 10 years post-treatment, although the incidence may be lower with modern techniques. Radiation pneumonitis is reported in 5% to 15% of lung cancer patients receiving definitive external-beam radiation therapy. A minority of patients may develop progressive pulmonary fibrosis; late complications include cor pulmonale and respiratory failure. Bleomycin-induced pneumonitis is an acute rather than late effect of treatment. Late pulmonary complications in bone marrow or stem cell transplantation patients who develop interstitial pneumonitis include idiopathic pneumonia syndrome and bronchiolitis obliterans.

CONCLUSION

An increased incidence of cardiac and/or pulmonary dysfunction is observed in cancer survivors. Research is needed to identify high-risk patients, and to determine the optimal screening strategies and subsequent treatment.

Late cardiac effects of anthracycline containing therapy for childhood acute lymphoblastic leukemia

BACKGROUND

At present about 80% of children with acute lymphoblastic leukemia (ALL) will be cured following treatment with multi-drug chemotherapy. A major concern for this growing number of survivors is the risk of late effects of treatment. The aim of this study was to determine whether signs of cardiomyopathy were present in patients treated in childhood with cumulative anthracycline doses of less than 300 mg/m(2).

PROCEDURE

Evaluation of cardiac function in a cohort of 63 long-term survivors in first continuous remission following treatment of ALL with multi-drug chemotherapy including anthracyclines was performed using standard M-mode echocardiography and tissue doppler imaging (TDI). Associations between age at diagnosis, cumulative dose of anthracycline, sex, length of follow-up, and deviations from normal values in M-mode echocardiograms were evaluated using univariate and multivariate regression analysis. TDI data were compared to normal values using Wilcoxon matched-pairs signed-ranks test.

RESULTS

By standard M-mode echocardiography the most significant findings were diastolic dilation of the left ventricle, thinner interventricular septum (IVS), decreased left ventricular mass (LVM) in females, follow-up dependent dilation of the left ventricle in systole and follow-up dependent decrease in ejection fraction (EF). TDI abnormalities included signs of early diastolic dysfunction and myocardial hypertrophy, and were also found in structures that appeared normal by M-mode echocardiography.

CONCLUSIONS

This study adds to the growing evidence that even low to moderate doses of anthracyclines might lead to progressive cardiac dysfunction. It is important that children treated with anthracyclines receive life long follow-up for signs of cardiomyopathy.

Monitoring left ventricular function in adults receiving anthracycline-containing chemotherapy

AIMS

To assess prospectively (1) the incidence of early anthracycline-induced cardiotoxicity; (2) the best predictor for identifying individuals at risk of developing functional cardiotoxicity; and (3) the most sensitive standard echocardiographic measure for the detection of anthracycline-induced changes in left ventricular (LV) function.

METHODS

Sixty-seven consecutive patients (45 male, mean age 50+/-18 years) requiring doxorubicin-containing chemotherapy were enrolled. Clinical and echocardiographic assessments occurred before they received any anthracycline, after low-dose anthracyclines and 1-3 months after completion of their chemotherapy.

RESULTS

Twenty six percent of patients without significant pre-existing cardiac disease developed cardiotoxicity. The parameter that best predicted the development of functional cardiotoxicity was the change in EF between baseline and low dose with an area under the curve of 0.92. The Tei index detected declines in LV function earlier in the course of treatment with anthracyclines and to a greater significance than any other standard echocardiographic measurement but did not predict functional cardiotoxicity.

CONCLUSIONS

All patients receiving potential cardiotoxic chemotherapy should be under the care of a cardiologist and have their EF monitored closely.

Radiation dose and long term risk of cardiac pathology following radiotherapy and anthracyclin for a childhood cancer

PURPOSE

To determine the cardiac status in children 15 years (yrs) or more after a solid tumour treatment.

PATIENTS AND METHODS

Of the 447 patients, 229 were fully studied and 218 were not. The following cardiac evaluation was proposed to all the 447 consecutive patients: (1) cardiac Doppler US by one of two expert cardiologists; (2) cardiac rhythm and conduction abnormalities including 24-h holter ECG; (3) (131)I-mIBG myocardial scintigraphy; (4) serum brain natriuretic peptide levels at rest; (5) an exercise test with VO(2)max measurement. The radiation dose delivered to 7 points in the heart was estimated for all patients who had received radiotherapy.

RESULTS

Cardiac disorder was diagnosed in 89 evaluated patients (39%) including 24 heart failures and 65 other asymptomatic cardiac diseases. When adjusting on potential confounders, cardiac disorder and cardiac failure risks were respectively linear (ERR at 1 Gy: 26%) and linear-quadratic (ERR at 1 Gy: 19%) functions of the average radiation dose received to the heart. No interaction between cumulative dose of adriamycin and average radiation dose was evidenced for cardiac disorders, but the ERR/Gy of cardiac failure was higher for patients receiving less than 350 mg/m(2) of Adriamycin.

CONCLUSION

Long term heart pathologies are probably one of the major iatrogenic risks encored by patients who survived a childhood cancer. This study strongly emphasizes the need to limit the heart irradiation during radiotherapy, particularly, for patients who also received or were susceptible to later received adriamycin.

Dosimetric comparison of proton and photon three-dimensional, conformal, external beam accelerated partial breast irradiation techniques

PURPOSE

To compare the dosimetry of proton and photon-electron three-dimensional, conformal, external beam accelerated partial breast irradiation (3D-CPBI).

METHODS AND MATERIALS

Twenty-four patients with fully excised, Stage I breast cancer treated with adjuvant proton 3D-CPBI had treatment plans generated using the mixed-modality, photon-electron 3D-CPBI technique. To facilitate dosimetric comparisons, planning target volumes (PTVs; lumpectomy site plus 1.5-2.0 cm margin) and prescribed dose (32 Gy) were held constant. Plans were optimized for PTV coverage and normal tissue sparing.

RESULTS

Proton and mixed-modality plans both provided acceptable PTV coverage with 95% of the PTV receiving 90% of the prescribed dose in all cases. Both techniques also provided excellent dose homogeneity with a dose maximum exceeding 110% of the prescribed dose in only one case. Proton 3D-CPBI reduced the volume of nontarget breast tissue receiving 50% of the prescribed dose by an average of 36%. Statistically significant reductions in the volume of total ipsilateral breast receiving 100%, 75%, 50%, and 25% of the prescribed dose were also observed. The use of protons resulted in small, but statistically significant, reductions in the radiation dose delivered to 5%, 10%, and 20% of ipsilateral and contralateral lung and heart. The nontarget breast tissue dosimetric advantages of proton 3D-CPBI were not dependent on tumor location, breast size, PTV size, or the ratio of PTV to breast volume.

CONCLUSIONS

Compared to photon-electron 3D-CPBI, proton 3D-CPBI significantly reduces the volume of irradiated nontarget breast tissue. Both approaches to accelerated partial breast irradiation offer exceptional lung and heart sparing.

Anthracycline-induced cardiotoxicity in children with cancer: strategies for prevention and management

The fact that anthracyclines are cardiotoxic seriously narrows their therapeutic index in cancer therapy. The cardiotoxic risk increases with the cumulative dose and may lead to congestive heart failure (CHF) and dilated cardiomyopathy in adults and in children. The prevention of anthracycline-induced cardiotoxicity is particularly important in children who can be expected to survive for decades after being cured of their malignancy. Attempts to reduce anthracycline cardiotoxicity have been directed towards: (i) decreasing myocardial concentrations of anthracyclines and their metabolites by dose limitation and schedule modification; (ii) developing less cardio-toxic analogs; and (iii) concurrently administering cardioprotective agents to attenuate the effects of anthracyclines on the heart. As regards schedule modification, avoidance of anthracycline peak levels may reduce the pathologic and clinical cardiotoxicity, although this has not always been observed. The analogs of doxorubicin, such as idarubicin and epirubicin, have similar cardiotoxicity to that of doxorubicin when given in amounts of equivalent myelotoxicity. Liposomal anthracyclines are a new class of agents that may permit more specific organ targeting, thereby producing less systemic and cardiac toxicity, but more studies are required to assess the advantages, if any, of these preparations over classical anthracyclines. The cardioprotective agent, dexrazoxane, an iron chelator, is highly effective and provides short-term cardioprotection to most patients receiving even the most intensive doxorubicin-containing regimens. Its long-term benefits remain to be determined. In addition, data remain insufficient to make specific recommendations regarding current use of dexrazoxane in children. It is thought that subtle abnormalities, related to anthracycline treatment in childhood, can develop into more permanent myocardial disease resulting in cardiomyopathy, which may progress to CHF. As regards the therapy of patients with anthracycline cardiotoxicity, two different situations have, therefore, to be considered: (i) if the patient presents with cardiac abnormalities, such as a reduction in fractional shortening at echocardiogram, without cardiac symptoms; and (ii) if the patient has CHF. In the presence of CHF, recovery with digitalis-diuretic therapy alone seldom occurs, and in patients who have refractory hemodynamic decompensation, heart transplantation is indicated. In patients with CHF, therapy with ACE inhibitors induces improvement in left ventricular structure and function, but this improvement is transient. Randomized clinical trials are, therefore, necessary to determine the effects of ACE inhibitors in mild-to-moderate left ventricular dysfunction. The beneficial effects of beta-adrenoceptor antagonists (beta-blockers) on cardiac function in heart failure due to anthracyclines seem comparable with those observed in other forms of heart failure with systolic dysfunction. Many drugs are available to treat children with CHF due to anthracycline treatment, but they are only palliative.

Cardioprotective effect of dexrazoxane during treatment with doxorubicin: a study using low-dose dobutamine stress echocardiography

AIM

To assess the late cardioprotective effect of dexrazoxane associated with doxorubicin during treatment of osteosarcoma by means of low-dose dobutamine stress echocardiography (LDDSE) in non-relapsed asymptomatic children and teenagers.

PATIENTS AND METHODS

The study population included 58 patients with osteosarcoma divided in three groups, with equivalent age range, gender proportion and body surface area. Group I (21 patients, 14 males, 15 +/- 4 years) was analyzed before chemotherapy and considered the control group; Group II (19 patients, 11 males, 19.7 +/- 4 years) was treated with 348.4 +/- 18 mg/m2 of doxorubicin only and Group III (18 patients, 14 male, 16.8 +/- 5 years) treated with 396.5 +/- 55 mg/m2 of doxorubicin with dexrazoxane in the ratio 10:1. The patients were submitted to LDDSE (maximal dose 5 microg/kg/min). No major side effects were observed. Heart rate, blood pressure, left ventricular diameters, end systolic wall stress (ESWS), and other diastolic and systolic function indexes were assessed at rest conditions and during LDDSE and compared between the three groups.

RESULTS

Group III received a doxorubicin dose significantly greater than Group II (P = 0.001). During LDDSE there were no significant changes in the diastolic function indexes in any of the groups, but there was a significant increase of systolic indexes and a decrease of ESWS in Group III compared to group II. There was no significant difference of any systolic functional parameters between Group I and III. Considering the ejection fraction (EF) at rest or at LDDSE, 13 patients (69.4%) in Group II and 5 patients (27.7%) in Group III were considered to have systolic dysfunction. (P = 0.02).

CONCLUSION

Myocardial response to LDDSE in patients treated with doxorubicin and dexrazoxane was similar to patients without chemotherapy and better than those treated with doxorubicin only, suggesting less cardiotoxicity.

Comparison of epirubicin and doxorubicin cardiotoxicity in children and adolescents treated within the German Cooperative Soft Tissue Sarcoma Study (CWS)

PURPOSE

Up to now, cardiotoxicity of epirubicin has been studied almost exclusively in adult cancer patients. The aim of this study was to investigate epirubicin in children and adolescents, in comparison with doxorubicin.

METHODS

About 172 soft tissue sarcoma patients (mean age at diagnosis: 8.3 years), treated with epirubicin (median cumulative dose: 450 mg/m2) or doxorubicin (median cumulative dose: 240 mg/m2) within the high-risk group of the CWS-96 study, were examined in a prospective multicentre study. Heart function was analysed by echocardiography, measuring left-ventricular fractional shortening (FS). The median follow up was 27.7 months.

RESULTS

Incidence of clinically manifest cardiomyopathy was 0% (0/60; 95% CI: 0-6.0%) in patients treated with epirubicin, and 0.9% (1/108; 95% CI: 0-5.1%) in patients treated with doxorubicin. A further three patients showed subclinical cardiomyopathy. There was no difference in FS between the two treatment arms.

CONCLUSIONS

Cardiotoxicity was low in our study. For the short term, cardiotoxicity seems to be only a minor problem in patients treated with epirubicin as applied in this cohort.

Late anthracycline cardiotoxicity protection by dexrazoxane (ICRF-187) in pediatric patients: echocardiographic follow-up

BACKGROUND

The authors conducted a retrospective study to determine whether dexrazoxane (ICRF-187) would reduce late anthracycline-induced cardiotoxicity in patients treated in childhood for hematological malignancy.

PATIENTS AND METHODS

The authors examined 108 patients (63 male, 45 female) 5-29 years old, (median 15 years). All patients were in long-term remission of their malignancy. The cardioprotection was given to 68 patients (39 male, 29 female), and standard treatment was used in 40 patients (24 male, 16 female). Dexrazoxane (cardioxane, Chiron Company, The Netherlands) was given in 20:1 ratio to anthracycline. The follow-up time was 2-20 years (mean 7 years). The control group consisted of 41 volunteers (22 males, 19 females) 4-31 years old (median 18 years). The cardiotoxicity has been defined as the presence of heart failure or the decline of shortening fraction below 30% or ejection fraction (EF) below 55%. The end-systolic wall stress (ESS), myocardial performance index (MPI; Tei index), and parameters of left ventricular diastolic filling were also assessed.

RESULTS

The anthracycline cardiomyopathy with the presence of heart failure was diagnosed in only one patient treated with a standard regimen. The pathological decline of fractional shortening was present in three (5%) and six (15%) patients with and without cardioprotection given, respectively. Similarly, none of the patients with cardioprotection revealed a pathological value of EF, while four (10%) patients without cardioprotection showed an EF decrease. Finally, ESS and isovolumic relaxation time were pathologically increased in the group without cardioprotection in comparison to the controls and to the group with cardioprotection. However, the MPI was significantly increased in both groups of patients.

CONCLUSIONS

Dexrazoxane reduces the risk of late clinical and subclinical cardiotoxicity and does not affect the response rates to chemotherapy and overall survival during the median follow-up period of 7 years (follow-up period 2-20 years).

Late cardiac evaluation of children with solid tumors after anthracycline chemotherapy

BACKGROUND

The therapeutic potential of anthracycline antibiotics is limited by their cardiotoxicity. Electrocardiography, exercise testing, and two-dimensional echocardiography are non-invasive techniques used in the follow-up of children for cardiotoxicity. Plasma B-type natriuretic peptide (BNP) levels are thought to be useful markers in the early detection of AC induced cardiomyopathy.

PROCEDURE

We evaluated cardiac status of 34 patients with solid tumors treated with anthracycline antibiotics. All of the patients were asymptomatic and had no evidence of residual malignancy. They were evaluated by electrocardiography, exercise testing, echocardiography, and plasma BNP levels measured before and after the exercise testing.

RESULTS

Electrocardiography revealed only minor abnormalities of little clinical significance. All of the patients completed the exercise testing without complication, and the duration of the exercise for each patient was between normal limits. Cardiac output (CO) and wall stress (WS) were significantly increased in patients, than in controls in echocardiographic evaluation of systolic functions (P < 0.001). Diastolic filling patterns showed various abnormalities; M-E, M-A, T-E, T-A, AT, and IVRT were significantly higher than those of controls. Mean plasma BNP levels of the patients (10.56 +/- 10.22 pg/ml) were significantly higher than BNP levels of the healthy controls (4.09 +/- 2.26 pg/ml) (P < 0.016), before exercise testing. The mean plasma BNP levels of the patients (15.70 +/- 14.06 pg/ml) were higher than resting state after exercise testing, but it was not statistically significant (P > 0.05).

CONCLUSION

Our findings demonstrated that echocardiographic and biochemical abnormalities could be found even at low cumulative doses of AC antibiotics. The use of serial echocardiographic studies and plasma BNP determinations to identify high-risk patients for cardiotoxicity needs to be verified by additional studies.

Cardiac abnormalities 15 years and more after adriamycin therapy in 229 childhood survivors of a solid tumour at the Institut Gustave Roussy

The purpose of this paper was to determine the cardiac status in children 15 years or more after adriamycin therapy for a solid tumour. Of the 447 pts, 229 pts were fully studied and 218 were not. The following cardiac evaluations were proposed to all the 447 consecutive patients (pts): (1) cardiac Doppler US by one of two expert cardiologists; (2) cardiac rhythm and conduction abnormalities including 24-hour holter ECG; (3) (131)l-mlBG myocardial scintigraphy; (4) serum brain natriuretic peptide levels at rest; (5) an exercise test with VO(2) max measurement. The radiation doses delivered to 6 points in the heart were estimated for all patients who had received radiotherapy. Congestive heart failure was diagnosed in 24 of 229 (10%) evaluated pts, with a median interval of 15 years (0.3-24 years) from the first symptom after adriamycin treatment. Among the 205 remaining pts, 13 asymptomatic pts (6%) had severe (n=4) (FS<20%) or marked (n=9) (20< or =FS<25%) systolic dysfunction. In the 192 others, the median meridional end-systolic wall stress was 91 (53-135) and it exceeded 100 g cm(-2) in 52 pts. Using a Cox model, only the cumulative dose of adriamycin and the average radiation dose to the heart, were identified as risk factors for a pathological cardiac status. In conclusion, the risk of cardiac failure or severe abnormalities increases with adriamycin treatment, radiotherapy and time since treatment, even after a follow-up of 15 years or more. In our series, after an average follow-up of 18 years, 39% of the children had a severe cardiac dysfunction or major ventricular overload conditions. The risk increases with the dose of adriamycin and radiation received to the heart, without evidence for threshold.

Regional cardiac wall motion abnormalities during and shortly after anthracyclines therapy

BACKGROUND

Tissue Doppler imaging (TDI) is a new non-invasive ultrasound technique that enables quantitative assessment of regional myocardial wall motion. A previous study of survivors of childhood malignancies demonstrated abnormalities of regional diastolic wall motion abnormalities many years after treatment with anthracyclines. The purpose of the present study was to investigate this phenomenon during and shortly after treatment.

PROCEDURE

A total of 60 patients, age range 4.4-16.0 years, were included in this study: 43 early survivors, with a mean follow-up duration of 2.1 (range 0.3-5.2) years from end of anthracycline treatment, were evaluated retrospectively. Seventeen other patients were evaluated before, during, and 6 months after the end of anthracycline therapy. All patients received moderate cumulative doses of anthracyclines (range 120-450 mg/m2). Echocardiographic examination was performed using standardized conventional and TDI techniques.

RESULTS

Of the early survivors, 26 (60%) demonstrated regional LV free wall motion abnormalities. In the prospective group, serial echocardiographic studies revealed three patients (18%) with regional abnormalities of LV free wall motion before starting chemotherapy, but 14 (82%) at the end of treatment. Six months later, however, the incidence decreased to 61% of the survivors. Subject and treatment characteristics, as well as LV wall diameters and fractional shortening were not significantly different for children with or without free wall motion abnormalities. Regional wall motion abnormalities were also seen in the interventricular septum, although this was less frequent.

CONCLUSIONS

Regional diastolic wall motion abnormalities are common during and shortly after anthracyclines therapy but may be transient. The authors recommend simultaneous use of both conventional echocardiography & TDI for the monitoring of anthracycline-induced cardiotoxicity.

The late consequences of anthracycline treatment on left ventricular function after treatment for childhood cancer

The purpose of this study was to determine the incidence of changes in left ventricular function in patients in long-term remission after treatment with anthracyclines for a childhood malignancy. The authors examined 155 patients in disease remission who underwent treatment protocols utilising anthracyclines in childhood. The group comprised 90 males and 65 females aged 15+/-4.9 years (range 5-29 years, median 15 years). The age at the time of diagnosis and start of treatment was 8.6+/-4.9 years (range 1-18 years, median 8 years). The time of follow-up was 7.3+/-4 years (range 1-21 years, median 6.3 years). The patients were given a cumulative dose of doxorubicin or daunorubicin of 250+/-131 mg/m2 (range 50-1200 mg/m2, median 240 mg/m2). The values of ejection fraction below 55% and fractional shortening below 30% assessed by means of echocardiography were considered as pathological. The control group consisted of 41 volunteers. Pathological values of fractional shortening were found in 12 patients (8%). Only one patient (0.64%) showed the development of heart failure due to cardiomyopathy. The group of the patients after chemotherapy revealed significantly worse values of left ventricular endsystolic wall stress, mean velocity of circumferential fibre shortening, Tei index, and isovolumic relaxation period in comparison with the control group. We found a correlation between the given cumulative dose of anthracyclines and indicators of systolic function of the left ventricle, but not a relation to the time indicators (age at diagnosis, time of follow-up).

CONCLUSION

in the mean period of 6 years after chemotherapy, subclinical cardiotoxicity was found in 11 patients (7%) and cardiomyopathy with heart failure in one patient. Further indicators of subclinical damage are elevation of afterload (end-systolic stress), impaired relaxation and increased value of the Doppler index of global left ventricular function. Further monitoring and evaluation of the relevant subclinical abnormalities over a longer period of time are needed.