Early decline in left ventricular ejection fraction predicts doxorubicin cardiotoxicity in lymphoma patients

Cardio-oncology: Concepts and practice

Substantial progress in cancer therapy increasingly allows higher cure rates, and even advanced disease can be stabilized, allowing improved survival with quality of life for months to years, meaning comorbid diseases are a growing determinant of outcome. Cardiovascular events substantially contribute to long-term morbidity and mortality in people living with or surviving cancer. In recognition of this, the subspecialty of cardio-oncology has emerged, and aims to promote cardiovascular heath, whilst facilitating the most effective cancer therapy. This review describes the concept of cardio-oncology, and illustrates the role played by a specialist team in improving outcomes, using heart failure secondary to breast cancer treatment as an example. We aim to highlight pivotal original research and comprehensive summaries of the most relevant topics, providing an overview for cardiologists and oncologists about this increasingly important medical problem.

Non-pegylated liposomal doxorubicin in lymphoma: patterns of toxicity and outcome in a large observational trial

The anthracycline doxorubicin plays a major role in the treatment of lymphoproliferative disorders. However, its use is often limited due to cardiac toxicity, which seems to be much less in the liposomal non-pegylated formulation (Myocet®). The aim of this study was the evaluation of efficacy and toxicity of Myocet®-containing treatment regimens, with a focus on cardiotoxicity during treatment in lymphoma patients. A total of 326 consecutive patients, treated between March 2008 and December 2013 in 11 Austrian and 1 Italian cancer centers, were retrospectively assessed. Patients' baseline and treatment-related parameters were obtained by reviewing hospital records. Median age was 74 years (range 26-93). The most common histology was DLBCL (60 %), followed by FL (13 %) and MCL (8 %). At least one cardiovascular comorbidity was present in 72 % of patients. Most common grade 3/4 toxicities were hematologic, namely, leukopenia, neutropenia, thrombocytopenia, and febrile neutropenia in 44, 40, 17, and 16 %. Overall, 43 patients suffered a cardiac event (any grade) with most patients developing congestive heart failure. Parameters significantly associated with severe cardiac events (grades 3-5) were the presence of cardiovascular comorbidities, chronic obstructive pulmonary disease, and elevated baseline NT-proBNP. Treatment response after first line Myocet®-containing therapy was ≥58 % among all entities (range 58-86 %) and therefore comparable to those of conventional therapeutic regimens. Herein, we provide a detailed toxicity profile of Myocet®-containing chemotherapy regimens. Despite the high rate of patients with preexisting comorbidities, the number of adverse events was encouraging. However, these results need to be confirmed in a prospective randomized trial.

Evaluation and management of patients with heart disease and cancer: cardio-oncology

The care for patients with cancer has advanced greatly over the past decades. A combination of earlier cancer diagnosis and greater use of traditional and new systemic treatments has decreased cancer-related mortality. Effective cancer therapies, however, can result in short- and long-term comorbidities that can decrease the net clinical gain by affecting quality of life and survival. In particular, cardiovascular complications of cancer treatments can have a profound effect on the health of patients with cancer and are more common among those with recognized or unrecognized underlying cardiovascular diseases. A new discipline termed cardio-oncology has thus evolved to address the cardiovascular needs of patients with cancer and optimize their care in a multidisciplinary approach. This review provides a brief introduction and background on this emerging field and then focuses on its practical aspects including cardiovascular risk assessment and prevention before cancer treatment, cardiovascular surveillance and therapy during cancer treatment, and cardiovascular monitoring and management after cancer therapy. The content of this review is based on a literature search of PubMed between January 1, 1960, and February 1, 2014, using the search terms cancer, cardiomyopathy, cardiotoxicity, cardio-oncology, chemotherapy, heart failure, and radiation.

Nuclear imaging in detection and monitoring of cardiotoxicity

Cardiotoxicity as a result of cancer treatment is a novel and serious public health issue that has a significant impact on a cancer patient’s management and outcome. The coexistence of cancer and cardiac disease in the same patient is more common because of aging population and improvements in the efficacy of antitumor agents. Left ventricular dysfunction is the most typical manifestation and can lead to heart failure. Left ventricular ejection fraction measurement by echocardiography and multigated radionuclide angiography is the most common diagnostic approach to detect cardiac damage, but it identifies a late manifestation of myocardial injury. Early non-invasive imaging techniques are needed for the diagnosis and monitoring of cardiotoxic effects. Although echocardiography and cardiac magnetic resonance are the most commonly used imaging techniques for cardiotoxicity assessment, greater attention is focused on new nuclear cardiologic techniques, which can identify high-risk patients in the early stage and visualize the pathophysiologic process at the tissue level before clinical manifestation. The aim of this review is to summarize the role of nuclear imaging techniques in the non-invasive detection of myocardial damage related to antineoplastic therapy at the reversible stage, focusing on the current role and future perspectives of nuclear imaging techniques and molecular radiotracers in detection and monitoring of cardiotoxicity.

Cardiac complications of chemotherapy: role of imaging

OPINION STATEMENT

New advances in cancer diagnosis and treatment have increased survival rates in patients with cancer. In parallel with this increase in the number of cancer survivors is an increasing prevalence of cardiac complications from cancer treatment. Chemotherapy-induced cardiac dysfunction is a major contributor to adverse morbidity and mortality rates in cancer patients. Evidence suggests that both clinical symptoms and the traditional left ventricular ejection fraction (LVEF) may lack sensitivity as measures of cardiotoxicity. The early identification of subclinical LV dysfunction is becoming increasingly important, as this may allow cancer patients and their physicians to make informed decisions about therapeutic options. The features of echocardiography make it a useful tool in the diagnosis and monitoring of cardiotoxicity. This review will examine the role of cardiac imaging in detecting cardiotoxicity, focusing primarily on the conventional and more recent echocardiographic approaches for assessing subclinical cardiotoxicity.

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.

Heart rate variability and heart rate turbulence in patients with hematologic malignancies subjected to high-dose chemotherapy in the course of hematopoietic stem cell transplantation

BACKGROUND

In hematological malignancies, remissions and cures may be achieved by hematopoietic stem cell transplantation (HSCT) following high-dose chemotherapy (HDC). Cardiotoxicity of such therapy has not yet been fully elucidated. Noninvasive approaches allowing to evaluate an autonomic control of the heart function include analyses of both heart rate variability (HRV) and heart rate turbulence (HRT).

METHODS

In 38 patients with hematological malignancies, 24-hour electrocardiography Holter monitoring , with HRV and HRT analysis before HSCT (A test) and after HSCT (B test), was performed.

RESULTS

The 24-hour analysis of HRV demonstrated that SDNN, SDNNi, rMSSD, and pNN50 parameters were significantly lower after HSCT as compared to the results obtained before the transplantation (P < 0.05). For period of diurnal activity and for night hours, SDANN, SDNNi, rMSSD, and pNN50 were significantly lower in B test, as compared to the results of A test (P < 0.05). The analysis of HRT demonstrated that turbulence onset parameter was significantly higher, and turbulence slope parameter was significantly lower in B test, as compared to A test (P < 0.05). The multifactorial stepwise backward regression analysis indicated that administration of cyclophosphamide and carmustine and higher concentrations of blood cholesterol represented risk factors for decreased HRV. Cyclophosphamide and higher triglyceride levels represented independent risk factors for decreased HRT.

CONCLUSIONS

In patients with hematopoietic malignancies treated with HSCT, decreased HRV and HRT were observed after chemotherapy and stem cells administration.

Nicorandil ameliorates mitochondrial dysfunction in doxorubicin-induced heart failure in rats: possible mechanism of cardioprotection

Despite of its known cardiotoxicity, doxorubicin is still a highly effective anti-neoplastic agent in the treatment of several cancers. In the present study, the cardioprotective effect of nicorandil was investigated on hemodynamic alterations and mitochondrial dysfunction induced by cumulative administration of doxorubicin in rats. Doxorubicin was injected i.p. over 2 weeks to obtain a cumulative dose of 18 mg/kg. Nicorandil (3 mg/kg/day) was given orally with or without doxorubicin treatment. Heart rate and aortic blood flow were recorded 24 h after receiving the last dose of doxorubicin. Rats were then sacrificed and hearts were rapidly excised for estimation of caspase-3 activity, phosphocreatine and adenine nucleotides contents in addition to cytochrome c, Bcl2, Bax and caspase 3 expression. Moreover, mitochondrial oxidative phosphorylation capacity, creatine kinase activity and oxidative stress markers were measured together with the examination of DNA fragmentation and ultrastructural changes. Nicorandil was effective in alleviating the decrement of heart rate and aortic blood flow and the state of mitochondrial oxidative stress induced by doxorubicin cardiotoxicity. Nicorandil also preserved phosphocreatine and adenine nucleotides contents by restoring mitochondrial oxidative phosphorylation capacity and creatine kinase activity. Moreover, nicorandil provided a significant cardioprotection via inhibition of apoptotic signaling pathway, DNA fragmentation and mitochondrial ultrastructural changes. Interestingly, nicorandil did not interfere with cytotoxic effect of doxorubicin against the growth of solid Ehrlich carcinoma. In conclusion, nicorandil was effective against the development of doxorubicin-induced heart failure in rats as indicated by improvement of hemodynamic perturbations, mitochondrial dysfunction and ultrastructural changes without affecting its antitumor activity.

Early cardiac function monitoring for detection of subclinical Doxorubicin cardiotoxicity in young adult patients with breast cancer

PURPOSE

As doxorubicin cardiotoxicity is considered irreversible, early detection of cardiotoxicity and prevention of overt heart failure is essential. Although there are monitoring guidelines for cardiotoxicity, optimal timing for early detection of subclinical doxorubicin cardiotoxicity is still obscure. The purpose of this study is to determine optimal timing of cardiac monitoring and risk factors for early detection of doxorubicin cardiotoxicity in young adult patients with breast cancer.

METHODS

Medical records of 1,013 breast cancer patients diagnosed from January 2009 to December 2010 is being reviewed and analyzed. Properly monitored patients are defined as patients who underwent transthoracic echocardiography before and after the chemotherapy. The definition of subclinical cardiotoxicity (SC) either decreases left ventricular ejection fraction (LVEF) more than 10% or the LVEF declines under 55% from baseline without heart failure symptoms.

RESULTS

Twenty-nine out of 174 (16.7%) properly monitored young adult female patients (mean age, 52±10 years old) developed SC. The mean interval of cardiac evaluation of SC group was 5.5±3.0 months. Among the risk factors, the history of coronary artery disease, cumulative dose of doxorubicin ≥300 mg/m(2) and use of trastuzumab after doxorubicin therapy were associated with development of SC. At cumulative dose of doxorubicin 244.5 mg/m(2), SC can be predicted (sensitivity, 71.4%; specificity, 70.9%; area under the curve, 0.741; 95% confidence interval, 0.608-0.874; p=0.001).

CONCLUSION

In young adult patients with breast cancer, SC was common at cumulative dose of doxorubicin <300 mg/m(2) and early performance of cardiac monitoring before reaching the conventional critical dose of doxorubicin might be a proper strategy for early detection of SC.

The relationship between changes in functional cardiac parameters following anthracycline therapy and carbonyl reductase 3 and glutathione S transferase Pi polymorphisms

The aim of this prospective clinical study is to evaluate the relationship between changes in functional cardiac parameters following anthracycline therapy and carbonyl reductase 3 (CBR3p.V244M) and glutathione S transferase Pi (GSTP1p.I105V) polymorphisms. Seventy patients with normal cardiac function and no history of cardiac disease scheduled to undergo anthracycline chemotherapy were included in the study. The patients' cardiac function was evaluated by gated blood pool scintigraphy and echocardiography before and after chemotherapy, as well as 1 year following therapy. Gene polymorphisms were genotyped in 70 patients using TaqMan probes, validated by DNA sequencing. A deteriorating trend was observed in both systolic and diastolic parameters from GG to AA in CBR3p.V244M polymorphism. Patients with G-allele carriers of GSTP1p.I105V polymorphism were common (60%), with significantly decreased PFR compared to patiens with AA genotype. Variants of CBR3 and GSTP1 enzymes may be associated with changes in short-term functional cardiac parameters.

Anthracycline induced cardiac toxicity in pediatric Ewing sarcoma: a longitudinal study

BACKGROUND

Reports on incidence and factors associated with anthracycline cardiotoxicity in patients with Ewing sarcoma vary and few studies evaluate effect over time. Longitudinal trends in cardiac function and prognostic value of % decline in ejection fraction (EF) during therapy have not been previously described in Ewing sarcoma.

PROCEDURE

A retrospective review of patients age <17 years, diagnosed with Ewing sarcoma during 1978-2006, treated at British Columbia Children's Hospital with anthracycline chemotherapy was undertaken. Echocardiograms performed pre-treatment, worst function during treatment, on therapy completion; worst function during surveillance and the most recent echocardiogram were reviewed. Cardiac toxicity was graded using Common Terminology Criteria for Adverse Events v 3.0 and 4.0.

RESULTS

Among 71 eligible patients, median age at diagnosis 11.1 years, median cumulative dose of anthracycline was 365 mg/m2 . There were 397 echocardiograms with 153 (39%) abnormal. There were 21/71 patients with EF < 50%, 11 with EF < 40% and five cardiac deaths including 2/3 patients post-cardiac transplant. The median time to worst cardiac function was 51 months. Post-therapy completion 16/71 patients with progressive decline in cardiac function were noted. No patient with 10-15% decline in EF during therapy developed cardiotoxicity. Younger age (P = 0.004) and low BMI (P = 0.034) as continuous variables with anthracycline administration by IV push (P = 0.03) were risk factors for cardiotoxicity on univariate analysis but not significant within logistic regression models.

CONCLUSIONS

The high incidence of cardiotoxicity associated with higher administered anthracycline dose, young age, bolus infusion, and EF decline warrants evaluation in a larger cohort.

Noninvasive diagnosis of chemotherapy related cardiotoxicity

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

Rehabilitative exercise in a rat model of doxorubicin cardiotoxicity

The use of exercise to minimize doxorubicin (DOX)-induced cardiotoxicity is gaining attention. However, very few clinically relevant reports exist investigating the effects of exercise performed during and following DOX treatments. The purpose of this study, therefore, was to examine the effects of voluntary wheel running during and following DOX treatment using two models of late-onset DOX cardiotoxicity in the rat. Female Sprague-Dawley rats received either DOX or saline injections using one of two separate treatment regimens. These regimens involved either daily or weekly DOX injections with cumulative doses for both protocols totaling 15 mg/kg. Daily DOX injections were 1 mg/kg and lasted for 15 consecutive days while weekly DOX injections were 2.5 mg/kg and lasted for six consecutive weeks with control animals receiving matched saline injection regimens. Immediately following the initial DOX/saline injection, animals were randomly housed in cages with voluntary running wheels or standard rat cages throughout DOX/saline treatments and continued until reaching 10 weeks. Cardiac function was then assessed using echocardiography and an isolated working heart model, and myosin heavy chain (MHC) isoform distribution was assessed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When compared wth controls, daily DOX treatment resulted in reduced running wheel distances at weeks 2-10 (P < 0.05), and weekly DOX treatment resulted in reduced running wheel distances at weeks 2, 6 and 10 (P < 0.05). Nonetheless, wheel running during and following daily and weekly DOX dosing protected against DOX-induced cardiotoxicity by preserving maximal mitral and aortic blood flow velocities, left ventricular developed pressure and MHC isoform expression. In conclusion, the overall reduced volume of activity during and following daily and weekly DOX treatments attenuated DOX-induced cardiac dysfunction suggesting that low-volume endurance training may be an effective rehabilitative approach in minimizing DOX cardiotoxicity in cancer patients.

Assessing the Cardiac Toxicity of Chemotherapeutic Agents: Role of Echocardiography

Advancements in cancer treatment have resulted in sufficient survival length for patients to experience treatment-related cardiac complications. In particular, chemotherapy-induced cardiac dysfunction significantly impacts morbidity and mortality rates in cancer patients. The presence of cardiotoxicity from chemotherapy has been traditionally assessed using clinical symptoms and decreases in left ventricular ejection fraction (LVEF). However, in this indication, LVEF lacks accuracy as a measure of subclinical cardiotoxicity and its prognostic value is controversial. There is an emphasis to identify subclinical and left ventricular dysfunction early, in order to allow cancer patients and their physicians to make informed decisions about therapeutic options. Echocardiography is a readily available noninvasive tool to measure cardiac function and plays a major role in the diagnosis of cardiotoxicity. This review focuses on the role of echocardiography in detecting cardiotoxicity, and will discuss conventional and more recent echocardiographic approaches for assessing subclinical cardiotoxicity.

Newest echocardiographic techniques for the detection of cardiotoxicity and heart failure during chemotherapy

Chemotherapy-induced cardiotoxicity has become a significant public health issue. Left ventricular ejection fraction is routinely used to monitor cardiotoxicity but fails to detect subtle alterations in cardiac function. Improvements in the measurement of left ventricular ejection fraction, physical or pharmacologic stressors, and novel cardiac functional indices may be useful in the detection of cardiotoxicity. The improvements in the detection and therapy of cancer have led to the emergence of chemotherapy-induced cardiotoxicity. New echocardiographic techniques may be useful in the detection of patients undergoing chemotherapy treatments who could benefit from alternative cancer treatments, therefore decreasing the incidence of cardiotoxicity.

Biweekly rituximab, cyclophosphamide, vincristine, non-pegylated liposome-encapsulated doxorubicin and prednisone (R-COMP-14) in elderly patients with poor-risk diffuse large B-cell lymphoma and moderate to high 'life threat' impact cardiopathy

This Phase II study assessed feasibility and efficacy of a biweekly R-COMP-14 regimen (rituximab, cyclophosphamide, non-pegylated liposome-encapsulated doxorubicin, vincristine and prednisone) in untreated elderly patients with poor-risk diffuse large B-cell lymphoma (DLBCL) and moderate to high ‘life threat’ impact NIA/NCI cardiac comorbidity. A total of 208 courses were delivered, with close cardiac monitoring, to 41 patients (median age: 73 years, range: 62–82; 37% >75 years) at a median interval of 15·6 (range, 13–29) days; 67% completed all six scheduled courses. Response rate was 73%, with 68% complete responses (CR); 4-year disease-free survival (DFS) and time to treatment failure (TTF) were 72% and 49%, respectively. Failures were due to early death (n = 3), therapy discontinuations (no-response n = 2; toxicity n = 6), relapse (n = 6) and death in CR (n = 3). Incidence of cardiac grade 3–5 adverse events was 7/41 (17%; 95% confidence interval: 8–31%). Time to progression and overall survival at 4-years were 77% and 67%, respectively. The Age-adjusted Charlson Comorbidity Index (aaCCI) correlated with failures (P = 0·007) with patients scoring ≤7 having a longer TTF (66% vs. 29%; P = 0·009). R-COMP-14 is feasible and ensures a substantial DFS to poor-risk DLBCL patients who would have been denied anthracycline-based treatment due to cardiac morbidity. The aaCCI predicted both treatment discontinuation rate and TTF.

Long-term cardiac and pulmonary complications of cancer therapy

Cardiac complications resulting from chemotherapy and radiation pose a significant risk for morbidity and mortality to the cancer survivor. Cardiac side effects may progress over time and are a concern for patients treated during childhood. Long-term pulmonary complications are relatively infrequent, and acute respiratory effects of drugs (mostly bleomycin) or radiation normally resolve early after therapy. Although most cardiovascular risk statistics and clinical experience are derived from patients treated before 1985, the modern radiation approach that limits the exposure of the heart and reduces the total dose seems to attenuate the previously observed cardiovascular risk. Potential preventive measures for high-risk patients are of increasing interest but remain experimental.

Exercise preconditioning provides long-term protection against early chronic doxorubicin cardiotoxicity

Acute doxorubicin (DOX) cardiotoxicity can be attenuated by exercise preconditioning, but little is known of whether this cardioprotection continues beyond 10 days post-DOX administration. The purpose of this study was to determine the effects of exercise preconditioning on early chronic DOX-induced cardiotoxicity. Male rats were randomly assigned to sedentary, treadmill, or wheel running groups. Treadmill and wheel running animals participated in a progressive treadmill training protocol or voluntary wheel running, respectively, for 10 weeks. Following the intervention, animals were further randomized to receive either DOX (sedentary + DOX, treadmill + DOX, wheel running + DOX) or saline (sedentary + saline, treadmill + saline, wheel running + saline). All animals then remained sedentary for 4 weeks. A 22% reduction in fractional shortening was observed in left ventricles from previously sedentary animals receiving DOX when compared with sedentary + saline. This degree of decline was not observed in treadmill + DOX and wheel running + DOX. Sedentary + DOX possessed significantly depressed mitral and aortic valve blood flow velocities when compared with sedentary + saline, but these decrements were not observed in treadmill + DOX and wheel running + DOX. Ex vivo analysis revealed that left ventricular developed pressure and maximal rate of pressure development were significantly lower in sedentary + DOX when compared to sedentary + saline. Treadmill and wheel running prior to DOX treatment protected against these decrements. Exercise cardioprotection was associated with preserved myosin heavy chain but not sarcoendoplasmic reticulum Ca(2+) ATPase 2a expression. In conclusion, 10 weeks of prior exercise protected against early chronic DOX cardiotoxicity suggesting that training status may be a determining factor in the degree of late-onset cardiotoxicity experienced by cancer patients undergoing treatment with DOX.

Left ventricular function assessed by two-dimensional speckle tracking echocardiography in long-term survivors of Hodgkin's lymphoma treated by mediastinal radiotherapy with or without anthracycline therapy

Anthracycline therapy is well known for its adverse cardiac effects. However, few studies have been performed of the long-term follow-up of myocardial function in adult survivors of Hodgkin's lymphoma receiving anthracycline. Two-dimensional speckle tracking echocardiography is an accurate angle-independent modality for the quantification of left ventricular (LV) function. The aim of the present study was to investigate the long-term effect of anthracycline on LV systolic function. Echocardiography was performed in 47 survivors of Hodgkin's lymphoma 22 ± 2 years after successful mediastinal radiotherapy with (n = 27) or without (n = 20) anthracycline (doxorubicin) treatment and in 20 healthy controls. LV function was assessed by the LV ejection fraction and global longitudinal and circumferential strain. Both patient groups had received a similar dosage of radiation, and doxorubicin was given at a total dose of 309 ± 92 mg. The global longitudinal strain was reduced in patients receiving anthracycline with mediastinal radiotherapy compared to the other group receiving mediastinal radiotherapy alone or combined radiotherapy and regimens without anthracyclines (-16.1 ± 1.9% vs -17.5 ± 1.7%, respectively, p <0.05). Both patient groups had reduced strain compared to the healthy controls (-20.4 ± 1.7%, both p <0.001). The circumferential strain was also reduced in the treatment groups (-18.3 ± 3.2% and -17.8 ± 3.6% vs -22.5 ± 2.1%, both p <0.001). The LV ejection fraction did not differ between the patient groups (55 ± 8% vs 56 ± 6%, p = 1.0) but was reduced compared to that of the controls (62 ± 5%, both p <0.05). In conclusion, myocardial function was reduced in the survivors of Hodgkin's lymphoma 2 decades after successful treatment consisting of mediastinal radiotherapy with or without chemotherapy. Patients receiving anthracycline therapy had additional negative long-tem effects on LV systolic function.

Left ventricular dysfunction in patients receiving cardiotoxic cancer therapies are clinicians responding optimally?

OBJECTIVES

The purpose of this study was to examine treatment practices for cancer therapy-associated decreased left ventricular ejection fraction (LVEF) detected on echocardiography and whether management was consistent with American College of Cardiology/American Heart Association guidelines.

BACKGROUND

Patients treated with anthracyclines or trastuzumab are at risk of cardiotoxicity. Decreased LVEF represents a Class I indication for drug intervention according to American College of Cardiology/American Heart Association guidelines.

METHODS

Patients receiving anthracycline or trastuzumab at Stanford University from October 2005 to October 2007 and who had undergone echocardiography before and after receiving an anthracycline or trastuzumab were identified. Chart review examined chemotherapy regimens, cardiac risk factors, imaging results, concomitant medications, and cardiology consultations.

RESULTS

Eighty-eight patients received therapy with an anthracycline or trastuzumab and had a pre-treatment and follow-up echocardiogram. Ninety-two percent were treated with anthracyclines, 17% with trastuzumab after an anthracycline, and 8% with trastuzumab without previous treatment with anthracycline. Mean baseline LVEF was 60%, with 14% having a baseline <55%. Forty percent had decreased LVEF (<55%) after anthracycline and/or trastuzumab treatment. Of these patients, 40% received angiotensin-converting enzyme inhibitor or angiotensin receptor blocker therapy, 51% beta-blocker therapy, and 54% cardiology consultation. Of patients with asymptomatic decreased LVEF, 31% received angiotensin-converting enzyme inhibitor or angiotensin receptor blocker therapy, 35% beta-blocker therapy, and 42% cardiology consultation. Of those with symptomatic decreased LVEF, 67% received angiotensin-converting enzyme inhibitor or angiotensin receptor blocker therapy, 100% beta-blocker therapy, and 89% cardiology consultation.

CONCLUSIONS

Many cancer survivors are not receiving treatment consistent with heart failure guidelines. There is substantial opportunity for collaboration between oncologists and cardiologists to improve the care of oncology patients receiving cardiotoxic therapy.

Targeted ultrasound imaging of apoptosis with annexin a5 microbubbles in acute Doxorubicin-induced cardiotoxicity

BACKGROUND

The aim of this study was to assess the feasibility of targeted ultrasound imaging on apoptosis with annexin A5 microbubbles (A5MB) in acute doxorubicin-induced cardiotoxicity.

METHODS

Avidinated and octafluoropropan-filled phospholipid microbubbles were conjugated with biotinylated annexin A5. To confirm the specific binding of A5MB, flow cytometry was performed with hydrogen peroxide induced apoptosis in rat aorta smooth muscle cells incubated with fluorescein-5-isothiocyanate (FITC) labeled annexin A5 and A5MB. Adult male rats were injected intraperitoneally with 5 mg/kg doxorubicin weekly for 3 weeks (n = 5). Control rats were injected with normal saline (n = 5). At 24 hours after the final treatment, triggering imaging was performed 15 min after an intravenous bolus injection of A5MB for washout of freely circulating microbubbles. After echocardiography, the heart was isolated for histological detection of apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay.

RESULTS

In the in vitro tests, fluorescence intensity was low for healthy cells and high for apoptotic cells when incubated with FITC-labeled annexin A5 and A5MB. Rats treated with doxorubicin showed significant contrast opacification of the myocardium on contrast echocardiography using A5MB. However, no opacification was observed in control rats. Apoptosis was confirmed by TUNEL assay in doxorubicin treated rats.

CONCLUSION

Acute doxorubicin-induced cardiomyopathy based on early apoptosis can be assessed and imaged with targeted ultrasound imaging using A5MB in rats.

Anticancer therapy induced cardiotoxicity: review of the literature

Innovative anticancer strategies have contributed to an improved survival of patients suffering from malignancies, and in some cases, have turned cancer into a chronic disease. Therefore, the early and particularly late onsets of adverse cardiovascular effects of systemic anticancer treatments are of increasing interest. Among a rapidly increasing variety of anticancer drugs, the anthracyclines and the monoclonal antibody, trastuzumab, are the agents with a well-known cardiotoxicity. The diagnostic work-up, the cardiotoxic risk of anthracyclines and trastuzumab, and additionally, cardiotoxicity as a risk factor of a multimodal therapeutic approach in breast cancer patients is discussed in this study.

Different anthracycline derivates for reducing cardiotoxicity in cancer patients

BACKGROUND

The use of anthracyclines is limited by the occurrence of cardiotoxicity. In an effort to prevent this cardiotoxicity, different anthracycline derivates have been studied.

OBJECTIVES

To determine the occurrence of cardiotoxicity with the use of different anthracycline derivates in cancer patients.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL), (The Cochrane Library, Issue 2, 2009), MEDLINE (1966 to 29 May 2009) and EMBASE (1980 to 2 June 2009). In addition, we searched reference lists of relevant articles, conference proceedings and ongoing-trials-databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which different anthracycline derivates were compared in cancer patients (children and adults).

DATA COLLECTION AND ANALYSIS

Two authors independently performed study selection, assessment of risk of bias and data-extraction including adverse effects.

MAIN RESULTS

We identified five RCTs of varying quality addressing epirubicin versus doxorubicin (1036 patients) with the same dose. The meta-analysis showed no evidence for a significant difference in the occurrence of clinical heart failure between the treatment groups (RR = 0.36, 95% CI 0.12 to 1.11). However, there is some suggestion of a lower rate of clinical heart failure in patients treated with epirubicin.We identified two RCTs with varying quality addressing liposomal-encapsulated doxorubicin versus conventional doxorubicin (521 patients). The meta-analysis showed a significantly lower rate of both clinical heart failure and clinical and subclinical heart failure combined in patients treated with liposomal-encapsulated doxorubicin (RR = 0.20, 95% CI 0.05 to 0.75 and RR = 0.38, 95% CI 0.24 to 0.59 respectively). It should be noted that in one of the studies patients in the liposomal-encapsulated doxorubicin group received a higher cumulative anthracycline dose than patients in the doxorubicin group.For the other possible combinations of different anthracycline derivates only one RCT (epirubicin versus liposomal-encapsulated doxorubicin) or no RCT was identified.

AUTHORS' CONCLUSIONS

We are not able to favour either epirubicin or doxorubicin when given with the same dose. Based on the currently available evidence on heart failure, we conclude that in adults with a solid tumour liposomal-encapsulated doxorubicin should be favoured over doxorubicin. For both epirubicin versus doxorubicin and liposomal-encapsulated doxorubicin versus conventional doxorubicin no conclusions can be made about the effects of treatment in children treated with anthracyclines and also not in patients diagnosed with leukaemia. More research is needed. For other combinations of anthracycline derivates not enough evidence was available to make definitive conclusions about the occurrence of cardiotoxicity in patients treated with anthracyclines.

Different anthracycline derivates for reducing cardiotoxicity in cancer patients

BACKGROUND

The use of anthracyclines is limited by the occurrence of cardiotoxicity. In an effort to prevent this cardiotoxicity, different anthracycline derivates have been studied.

OBJECTIVES

To determine the occurrence of cardiotoxicity with the use of different anthracycline derivates in cancer patients.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL), (The Cochrane Library, Issue 2, 2009), MEDLINE (1966 to 29 May 2009) and EMBASE (1980 to 2 June 2009). In addition, we searched reference lists of relevant articles, conference proceedings and ongoing-trials-databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which different anthracycline derivates were compared in cancer patients (children and adults).

DATA COLLECTION AND ANALYSIS

Two authors independently performed study selection, assessment of risk of bias and data-extraction including adverse effects.

MAIN RESULTS

We identified five RCTs of varying quality addressing epirubicin versus doxorubicin (1036 patients) with the same dose. The meta-analysis showed no evidence for a significant difference in the occurrence of clinical heart failure between the treatment groups (RR = 0.36, 95% CI 0.12 to 1.11). However, there is some suggestion of a lower rate of clinical heart failure in patients treated with epirubicin.We identified two RCTs with varying quality addressing liposomal-encapsulated doxorubicin versus conventional doxorubicin (521 patients). The meta-analysis showed a significantly lower rate of both clinical heart failure and clinical and subclinical heart failure combined in patients treated with liposomal-encapsulated doxorubicin (RR = 0.20, 95% CI 0.05 to 0.75 and RR = 0.38, 95% CI 0.24 to 0.59 respectively). It should be noted that in one of the studies patients in the liposomal-encapsulated doxorubicin group received a higher cumulative anthracycline dose than patients in the doxorubicin group.For the other possible combinations of different anthracycline derivates only one RCT (epirubicin versus liposomal-encapsulated doxorubicin) or no RCT was identified.

AUTHORS' CONCLUSIONS

We are not able to favour either epirubicin or doxorubicin when given with the same dose. Based on the currently available evidence on heart failure, we conclude that in adults with a solid tumour liposomal-encapsulated doxorubicin should be favoured over doxorubicin. For both epirubicin versus doxorubicin and liposomal-encapsulated doxorubicin versus conventional doxorubicin no conclusions can be made about the effects of treatment in children treated with anthracyclines and also not in patients diagnosed with leukaemia. More research is needed. For other combinations of anthracycline derivates not enough evidence was available to make definitive conclusions about the occurrence of cardiotoxicity in patients treated with anthracyclines.

Different dosage schedules for reducing cardiotoxicity in cancer patients receiving anthracycline chemotherapy

BACKGROUND

The use of anthracycline chemotherapy is limited by the occurrence of cardiotoxicity. To prevent this cardiotoxicity, different anthracycline dosage schedules have been studied.

OBJECTIVES

To determine the occurrence of cardiotoxicity with the use of different anthracycline dosage schedules (i.e. peak doses and infusion durations) in cancer patients.

SEARCH STRATEGY

We searched the databases of The Cochrane Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 4, 2008), MEDLINE (1966 to November 2008) and EMBASE (1980 to November 2008). Also, we searched reference lists of relevant articles, conference proceedings and ongoing trials databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which different anthracycline dosage schedules were compared in cancer patients (children and adults).

DATA COLLECTION AND ANALYSIS

Two authors independently performed the study selection, the risk of bias assessment and the data-extraction.

MAIN RESULTS

We identified seven RCTs addressing different anthracycline infusion durations. The meta-analysis showed a statistically significant lower rate of clinical heart failure with an infusion duration of 6 hours or longer as compared to a shorter infusion duration (relative risk (RR) = 0.27; 95% confidence interval (CI) 0.09 to 0.81; 5 studies; 557 patients). The majority of patients included in these studies were adults with different solid tumours. For different anthracycline peak doses we identified two RCTs addressing a doxorubicin peak dose of less than 60 mg/m(2) versus 60 mg/m(2) or more, one RCT addressing a liposomal doxorubicin peak dose of 25 mg/m(2) versus 50 mg/m(2) and one RCT addressing an epirubicin peak dose of 83 mg/m(2) versus 110 mg/m(2). In none of the studies a significant difference in the occurrence of clinical heart failure was identified. All patients included in these studies were adults with different solid tumours.

AUTHORS' CONCLUSIONS

An anthracycline infusion duration of six hours or longer reduces the risk of clinical heart failure and it seems to reduce the risk of subclinical cardiac damage. Since there is only a small amount of data for children and data obtained in adults cannot be extrapolated to children, different anthracycline infusion durations should be evaluated further in children.No significant difference in the occurrence of clinical heart failure was identified in patients treated with a doxorubicin peak dose of less than 60 mg/m(2) or 60 mg/m(2) or more. For the other identified peak doses only one RCT was available, so no definitive conclusions can be made about the occurrence of cardiotoxicity. More high quality research is needed, both in children and adults and in leukaemias and solid tumours.

Consensus statement concerning cardiotoxicity occurring during haematopoietic stem cell transplantation in the treatment of autoimmune diseases, with special reference to systemic sclerosis and multiple sclerosis

Autologous haematopoietic stem cell transplantation is now a feasible and effective treatment for selected patients with severe autoimmune diseases. Worldwide, over 650 patients have been transplanted in the context of phase I and II clinical trials. The results are encouraging enough to begin randomised phase III trials. However, as predicted, significant transplant-related morbidity and mortality have been observed. This is primarily due to complications related to either the stage of the disease at transplant or due to infections. The number of deaths related to cardiac toxicity is low. However, caution is required when cyclophosphamide or anthracyclines such as mitoxantrone are used in patients with a possible underlying heart damage, for example, systemic sclerosis patients. In November 2002, a meeting was held in Florence, bringing together a number of experts in various fields, including rheumatology, cardiology, neurology, pharmacology and transplantation medicine. The object of the meeting was to analyse existing data, both published or available, in the European Group for Blood and Marrow Transplantation autoimmune disease database, and to propose a safe approach to such patients. A full cardiological assessment before and during the transplant emerged as the major recommendation.

Cardiovascular toxicity caused by cancer treatment: strategies for early detection

Cardiovascular toxicity is one of the most devastating complications of cancer treatment and can arise during or shortly after treatment, or even several years later. Identification of the left ventricular ejection fraction (LVEF) is the most common method to screen for toxic effects on the heart; however, this approach underestimates cardiac damage and additional strategies for the monitoring of treatment-induced cardiotoxicity are being explored. Guidelines for monitoring have been formulated for several cancer treatments; however, appropriate underlying evidence is still largely absent. In this Review, we summarise conventional and contemporary methods for early detection of cardiotoxicity and designate a level of evidence for the basis of each method.

Doxorubicin inactivates myocardial cytochrome c oxidase in rats: cardioprotection by Mito-Q

Doxorubicin (DOX) is used for treating various cancers. Its clinical use is, however, limited by its dose-limiting cardiomyopathy. The exact mechanism of DOX-induced cardiomyopathy still remains unknown. The goals were to investigate the molecular mechanism of DOX-induced cardiomyopathy and cardioprotection by mitoquinone (Mito-Q), a triphenylphosphonium-conjugated analog of coenzyme Q, using a rat model. Rats were treated with DOX, Mito-Q, and DOX plus Mito-Q for 12 weeks. The left ventricular function as measured by two-dimensional echocardiography decreased in DOX-treated rats but was preserved during Mito-Q plus DOX treatment. Using low-temperature ex vivo electron paramagnetic resonance (EPR), a time-dependent decrease in heme signal was detected in heart tissues isolated from rats administered with a cumulative dose of DOX. DOX attenuated the EPR signals characteristic of the exchange interaction between cytochrome c oxidase (CcO)-Fe(III) heme a3 and CuB. DOX and Mito-Q together restored these EPR signals and the CcO activity in heart tissues. DOX strongly downregulated the stable expression of the CcO subunits II and Va and had a slight inhibitory effect on CcO subunit I gene expression. Mito-Q restored CcO subunit II and Va expressions in DOX-treated rats. These results suggest a novel cardioprotection mechanism by Mito-Q during DOX-induced cardiomyopathy involving CcO.

Anandamide Preserves Cardiac Function and Geometry in an Acute Doxorubicin Cardiotoxicity Rat Model

We investigated the use of the endocannabinoid anandamide as a means of cardioprotection against doxorubicin-induced cardiac dysfunction. Male rats received doxorubicin with or without anandamide pretreatment. Cardiac function was assessed in vivo using transthoracic echocardiography and ex vivo using the isolated working heart 5 days posttreatment. Doxorubicin administration without anandamide pretreatment resulted in a decline in fractional shortening (P < .05) and left ventricular wall thickness when compared to controls (P < .05). Ex vivo cardiac function analysis revealed a reduction in left ventricular developed pressure in hearts from animals receiving doxorubicin without anandamide pretreatment when compared to controls (P < .05). Left ventricles from animals receiving anandamide pretreatment before doxorubicin administration did not exhibit depressed fractional shortening, ventricular wall thickness, or developed pressure when compared to controls (P > .05). These results suggest that a potential therapy for doxorubicin-induced cardiotoxicity involves targeting the endogenous cannabinoid system.

Acute exercise protects against doxorubicin cardiotoxicity

Numerous methods have been used to minimize the cardiotoxic effects of the chemotherapeutic agent doxorubicin (DOX), and most have had limited success. Chronic endurance exercise has been shown to protect against DOX cardiotoxicity, but little is known regarding the effects of acute exercise on DOX-induced cardiac dysfunction.

PURPOSE

The purpose of this study was to determine the effects of a single bout of acute endurance exercise on the cardiac dysfunction associated with DOX treatment.

METHODS

Male Sprague-Dawley rats either performed an acute exercise bout on a motorized treadmill for 60 minutes at a maximal speed of 25 m/min with a 5% grade (EX) or remained sedentary (SED) 24 hours before receiving either a 15-mg/kg DOX bolus dose or saline (SAL). Cardiac function was then analyzed 5 days post injection using a Langendorff isolated perfused heart model. In addition, myocardial lipid peroxidation was analyzed as an indicator of oxidative stress.

RESULTS

Doxorubicin treatment alone (SED+DOX) promoted a significant decline in end-systolic pressure (-35%), left ventricular developed pressure (-59%), and the maximal rate of left ventricular pressure development (-43%) as well as a 45% increase in lipid peroxidation products when compared with SED+SAL (P<.05). Acute exercise 24 hours before DOX treatment, however, had a cardioprotective effect, as end-systolic pressure, left ventricular developed pressure, and the maximal rate of left ventricular pressure development were significantly higher in EX+DOX compared with SED+DOX (P<.05) and EX+DOX had similar levels of lipid peroxidation products as SED+SAL CONCLUSIONS: An acute exercise bout performed 24 hours before DOX treatment protected against cardiac dysfunction, and this exercise-induced cardioprotection may partly be explained by a reduction in the generation of reactive oxygen species.

Combination of sorafenib and doxorubicin in patients with advanced hepatocellular carcinoma: results from a phase I extension trial

Sorafenib, an oral multikinase inhibitor, shows efficacy in renal cell and hepatocellular carcinoma (HCC) and is well tolerated when combined with doxorubicin in other solid tumours. Eighteen patients with inoperable HCC received doxorubicin 60 mg/m(2) IV for up to six 3-week cycles. Sorafenib 400mg bid was administered continuously starting day 4. Patients discontinuing doxorubicin were eligible for sorafenib monotherapy. The most frequent grade 3-4 drug-related adverse events were neutropaenia (61%), leukopaenia (45%) and diarrhoea (17%, grade 3). Seven of eight patients who completed six cycles of doxorubicin continued treatment with sorafenib for at least 3 months. Doxorubicin moderately increased AUC (21%) and C(max) (33%) when administered with sorafenib. The disease control rate for 16 evaluable patients was 69%. Sorafenib plus doxorubicin appears to be well tolerated and more effective in the treatment of HCC than doxorubicin alone. Follow-up with single-agent sorafenib in these patients also appears to be well tolerated.

Anthracycline-induced cardiomyopathy

Anthracyclines are potent chemotherapeutic agents associated with 3 different forms of cardiomyopathy. Acute cardiomyopathy is seen within 3 months of drug exposure and may take the form of either a reversible myocarditis and pericarditis or an early-onset type and a late-onset type of chronic cardiomyopathy. Chronic anthracycline-induced cardiomyopathy is treated similarly to ischemic cardiomyopathies with beta-blockade and angiotensin-converting enzyme (ACE) inhibition. This review focuses on recent research regarding mechanisms of anthracycline-induced myocardial damage, the noninvasive imaging diagnosis of anthracycline-induced cardiomyopathy, and potential areas of future research regarding genetic screening and selecting individuals at increased risk, with consideration of prophylactic treatment with medications, specifically carvedilol and ACE inhibitors.

Exercise preconditioning protects against doxorubicin-induced cardiac dysfunction

The clinical use of the chemotherapeutic drug doxorubicin (DOX) is limited due to a dose-dependent cardiotoxicity. Evidence is mounting that exercise protects against DOX-related cardiac dysfunction, and as such, it may be possible that prior endurance training promotes defense against DOX cardiotoxicity.

PURPOSE

To examine the effects of exercise preconditioning on acute DOX-induced cardiotoxicity, and to determine whether any observed cardioprotection was associated with myosin heavy chain (MHC) isoform alterations.

METHODS

Male Sprague-Dawley rats trained on a motorized treadmill, had access to voluntary running wheels, or remained sedentary for 10 wk prior to being injected with either saline or 10 mg.kg(-1) DOX. Left ventricular function was then assessed in vivo using transthoracic echocardiography and ex vivo using the isolated working heart at 5 and 10 d after injection. Additionally, left ventricular MHC isoform expression was analyzed as a possible mechanism to explain exercise-induced cardioprotection.

RESULTS

DOX treatment promoted significant in vivo and ex vivo cardiac dysfunction at 5 and 10 d after injection in sedentary animals, and this dysfunction was associated with an upregulation of the beta-MHC isoform. Exercise preconditioning protected against DOX-induced cardiac dysfunction at 5 and 10 d after injection by attenuating beta-MHC upregulation.

CONCLUSION

Endurance training prior to DOX treatment protects against acute DOX cardiotoxicity for up to 10 d, and this protection can potentially be explained by a preservation of MHC isoform distribution.

Usefulness of myocardial performance index and biochemical markers for early detection of anthracycline-induced cardiotoxicity in adults

BACKGROUND

Anthracycline therapy is limited by cardiotoxicity. Currently no diagnostic parameter is available allowing ubiquitous and reliable detection of preclinical anthracycline cardiomyopathy and prediction of prognosis.

PATIENTS AND METHODS

In 100 consecutive patients receiving anthracycline-based chemotherapy serial measurements of left ventricular systolic and diastolic function, Tei index (a Doppler echocardiographic parameter of global ventricular function), cardiac troponin T (cTnT) and NT-probrain natriuretic peptides (BNP) at baseline and during 1-year follow-up were performed.

RESULTS

Mean ejection fraction (LVEF) significantly decreased immediately after completion of anthracycline therapy (mean dose 226.1 +/- 8.3 mg/m(2)) und further declined during follow-up (65.9 +/- 0.6% Vs. 61.6 +/- 0.7%; P < 0.001), while mean E/A ratio decreased after 6 months (P = 0.05). No patient presented with cardiac symptoms. The Tei index increased after therapy in the majority of patients (78.8%) compared with pre-therapy values indicating myocardial alteration in more patients than previously recognized. cTnT levels did not exceed the upper limit of the normal range in any patient. Seven patients had low-level elevations of cTnT. Only one of these patients developed a concomitant decrease in LVEF. Mean N-terminal-pro-BNP (NT-proBNP) levels did not significantly change after anthracycline administration. However, in 13 patients (15.3%) a marked, transient increase of NT-proBNP was obtained after the first anthracycline cycle without cardiac dysfunction presumably due to altered cardiac loading conditions during chemotherapy.

CONCLUSION

Low to moderate doses of anthracyclines resulted in subclinical myocardial alteration in more patients than so far noticed. Clinical implications of increased Tei index remain to be determined in long-term. Our results do not support that assessment of cTnT or BNP levels may safely replace serial echocardiographic evaluation of systolic and diastolic function for the monitoring of anthracycline cardiotoxicity.

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.

Different dosage schedules for reducing cardiotoxicity in cancer patients receiving anthracycline chemotherapy

BACKGROUND

The use of anthracycline chemotherapy is limited by the occurrence of cardiotoxicity. In an effort to prevent this cardiotoxicity, different anthracycline dosage schedules (i.e. peak doses and infusion durations) have been studied.

OBJECTIVES

The primary objective was to determine the occurrence of cardiotoxicity with the use of different anthracycline dosage schedules in cancer patients.

SEARCH STRATEGY

We searched the databases of The Cochrane Register of Controlled Trials (CENTRAL), (The Cochrane Library, Issue 2, 2004), MEDLINE (1966 to June 2004) and EMBASE (1980 to June 2004). In addition, we searched reference lists of relevant articles, conference proceedings and ongoing trials databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which different anthracycline dosage schedules were compared in cancer patients (children and adults).

DATA COLLECTION AND ANALYSIS

Two authors independently performed the study selection, quality assessment and data-extraction including adverse effects.

MAIN RESULTS

We identified six RCTs of varying quality addressing different anthracycline infusion durations (625 patients). The meta-analysis showed a statistically significant lower rate of clinical heart failure with an infusion duration of 6 hours or longer as compared to a shorter infusion duration, i.e. maximal duration of 1 hour (RR = 0.27; 95% confidence interval (CI) 0.09 to 0.81; 5 studies; 557 patients). In individual studies the infusion duration of 6 hours or longer also seemed to reduce the risk of subclinical cardiac damage. No statistically significant difference in response rate was found (RR = 0.83; 95% CI 0.45 to 1.54; 2 studies; 292 patients). No statistically significant difference in overall survival was found (HR = 1,42; 95% CI 0.61 to 3.30; 2 studies; 322 patients), but there was unexplained heterogeneity (I(2)=75%). No conclusions can be made regarding adverse effects. It should be emphasised that the majority of patients included in these studies were adults with different solid tumours. Children with leukaemia could not be included in the performed meta-analyses, but they were included in the descriptive results of non-pooled studies. No RCTs addressing different anthracycline peak doses with the same cumulative anthracycline dose in both treatment groups were identified.

AUTHORS' CONCLUSIONS

An anthracycline infusion duration of six hours or longer reduces the risk of clinical heart failure, and it seems to reduce the risk of subclinical cardiac damage. There is no evidence which suggests a difference in response rate and survival between both treatment groups. Since there is only a small amount of data for children and also because data obtained in adults cannot be extrapolated to children, different anthracycline infusion durations should be evaluated further in children. For different anthracycline peak doses no high quality evidence was available and therefore, no definitive conclusions can be made about the occurrence of cardiotoxicity in patients treated with different anthracycline peak doses.