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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

Objectives

The purpose of this study was to assess the timing of changes in serial echocardiographic parameters in pediatric cancer survivors and to evaluate their associations with cardiomyopathy development.

Background

Pediatric cancer survivors undergo serial echocardiograms to screen for cardiotoxicity. It is not clear whether small longitudinal changes in functional or structural parameters over time have clinical significance.

Methods

This is a multicenter, retrospective, case-control study of ≥1-year survivors following the end of cancer therapy. Cardiomyopathy cases (fractional shortening [FS] ≤28% or ejection fraction [EF] ≤50% on ≥2 occasions) were matched to control subjects (FS ≥30%, EF ≥55%, not on cardiac medications) by cumulative anthracycline and chest radiation dose, follow-up duration, and age at diagnosis. Digitally archived clinical surveillance echocardiograms were quantified in a central core laboratory, blinded to patient characteristics. Using mixed models with interaction terms between time and case status, we estimated the least square mean differences of 2-dimensional, M-mode, pulsed wave Doppler, and tissue Doppler imaging–derived parameters over time between cases and control subjects.

Results

We identified 50 matched case-control pairs from 5 centers. Analysis of 412 echocardiograms (cases, n = 181; control subjects, n = 231) determined that indices of left ventricular systolic function (FS, biplane EF), diastolic function (mitral E/A ratio), and left ventricular size (end-diastolic dimension z-scores) were significantly different between cases and control subjects, even 4 years prior to the development of cardiomyopathy.

Conclusions

Longitudinal changes in cardiac functional parameters can occur relatively early in pediatric cancer survivors and are associated with the development of cardiomyopathy.

Trends in the off-label use of β-blockers in pediatric patients

The use of US Food and Drug Administration (FDA)-approved drugs for the treatment of an unapproved indication or in an unapproved age group, or at doses or route of administration not indicated on the label is known as off-label use. Off-label use may be beneficial in circumstances when the standard-of-care treatment has failed, and/or no other FDA-approved medications are available for a particular condition. In pediatric patients, off-label use may increase the risk of adverse events as pharmacokinetic and pharmacodynamic data are limited in children. Approximately 73% of off-label drugs currently prescribed for various conditions do not have sufficient scientific evidence for safety and efficacy. For example, β-blockers are a class of drugs with FDA-approval for very few indications in pediatrics but are commonly used for various off-label indications. Interestingly, the proportion of off-label use of β-blockers in adults is at about 52% (66.2 million) of the total number of β-blockers prescribed. The frequency of off-label use of β-blockers in children is also high with limited data on the indications as well as safety and efficacy. We present trends in off-label use of β-blockers in children to discuss drug safety and efficacy and include recommendations for pediatric providers.

Protective effects of olmesartan and l-carnitine on doxorubicin-induced cardiotoxicity in rats

Doxorubicin (DOX), an anthracycline antibiotic, is an important antineoplastic agent due to its high antitumor efficacy in hematological as well as in solid malignancies. The clinical use of DOX is limited due to its cardiotoxic effects. The present study aimed to investigate the possible protective effect of olmesartan (Olm), l-carnitine (L-CA), and their combination in cardiotoxicity induced by DOX in rats. Male albino rats were randomly divided into seven experimental groups (n = 8): group I: normal control, group II: L-CA, group III: Olm, group IV: DOX. The other three groups were treated with Olm (10 mg/kg), L-CA (300 mg/kg), and their combination for 2 weeks after induction of cardiotoxicity by a single dose of DOX (20 mg/kg). In the results, DOX showed a significant elevation in serum troponin I, creatine kinase-MB (CK-MB), and lactate dehydrogenase (LDH) together with increased inflammation manifested by the rise of tumor necrosis factor-alpha (TNF-α), intercellular adhesion molecules-1 (ICAM-1), interleukin IL-1β (IL-1β), myeloperoxidase (MPO), nuclear factor-kappa B (NF-κB), and transforming growth factor beta (TGF-β) in cardiac tissues as well as DOX-induced oxidative stress by increasing in malondialdehyde (MDA) and decreasing in superoxide dismutase (SOD) and glutathione (GSH) in heart tissues. In addition, caspase-3 activity was boosted as indication of increased apoptosis. On the other hand, administration of L-CA and Olm attenuated the DOX-evoked disturbances in the abovementioned parameters. In addition, DOX exhibited echocardiographic changes and severe histopathological changes, which were significantly reversed by L-CA and Olm treatment. In conclusion, the present study data confirm the protective role of L-CA and Olm in DOX-induced cardiotoxicity, which may be related to its antioxidant, antiinflammatory, and antiapoptotic agents.

Tissue Doppler Imaging for anthracycline cardiotoxicity monitoring in pediatric patients with cancer

BACKGROUND

Cardiotoxic effects of anthracycline therapy are a major cause of morbidity for childhood cancer survivors. The aim of this retrospective evaluation is to assess the efficacy of Tissue Doppler Imaging in the early detection of myocardial alterations in these patients.

METHODS

A population of 50 childhood cancer survivors (32 males and 18 females) who have been treated with anthracyclines was evaluated by standard and TDI echocardiographic examination of the basal and median region of the interventricular septum (IVSb, IVSm), of the left ventricular posterior wall (LVPWb, LVPWm), and of the mitral annulus; the results were compared with those obtained from a population of 50 healthy age-matched and sex-matched controls by using the Student test. The clinical and echocardiographic data of the two groups were compared also with the independent samples t-test. All data were expressed as mean ± standard deviation. A two-tailed P-value < 0.05 was considered statistically significant. Statistical analysis was performed using STATA 7.0.

RESULTS

The case-control analysis showed statistically significant differences (p < 0,05) between the patients and the controls values. The systolic performance of the patients was normal (LVEF (p = 0,0029) and LVFS (p = 0,0002)). Statistically significant differences between patients and controls were found for diastolic function measurements obtained with PW Doppler such as IVRT (p = 0,0000), DT (p = 0,0041), E (p = 0,0000), A (p = 0,0458), even if E/A ratio was not altered. TDI analysis also show significant differences between patients and controls in both LVPW and IVS (basal and middle segments); E/E' ratio and E'/A' ratio did not vary significantly. Linear Regression and multivariate analysis showed that Hematopoietic Stem Cell Transplantation had the highest impact on our measurements.

CONCLUSIONS

The results showed a myocardial diastolic impairment with preserved ejection fraction. Since the median follow-up time of our cohort was 2 years, further evaluation is needed to better define the diastolic alterations. TDI analysis showed high sensitivity for the detection of mild myocardial dysfunction; the implementation of this novel method as standard practice in the follow-up of selected childhood cancer survivors might help to achieve a better management of long-term complications of cardiotoxic chemotherapy.

State of the art review: Chemotherapy-induced cardiotoxicity in children

Chemotherapy-induced cardiotoxicity in adults and children is a topic with a growing interest in the cardiology literature. The ability to detect cardiac dysfunction in a timely manner is essential in order to begin adequate treatment and prevent further deterioration. This article aims to provide a review on the myocardial injury process, chemotherapeutic agents that lead to cardiotoxicity, the definition of cardiotoxicity, and the methods of timely detection and treatment.

Protective Effect of Acetyl-L-Carnitine Against Doxorubicin-induced Cardiotoxicity in Wistar Albino Rats

BACKGROUND AND AIMS

Anthracyclines are one of the most preferred agents in practical pediatric oncology despite their dose-dependent cardiotoxic effects. The aim of this study was to investigate whether or not acetyl-L-carnitine (ALCAR) has protective effects on doxorubicin (DOX)-induced cardiotoxicity.

METHODS

Wistar rats were divided into four groups; control, DOX, ALCAR and ALCAR+DOX. Rats in the first group were given saline on study days, whereas those in the second group were given a single dose of DOX on the 5^th day and saline on the other days. Rats in the third group were given ALCAR and those in the fourth group were given ALCAR on study days but also given only a single dose of DOX on the fifth day of the study. Ejection fractions (EF) were measured by echocardiography before and after drug administration. Heart tissues were evaluated by light and electron microscopy. Apoptotic cells were determined with TUNEL and caspase-3 staining.

RESULTS

DOX significantly decreased the EF values, whereas ALCAR did not. Cardiac functions were higher in the ALCAR+DOX group when compared to the DOX group. DOX administration caused a cardiac injury not only functionally, but also structurally, whereas ALCAR prevented it.

CONCLUSIONS

ALCAR has a capacity of preventing DOX-induced cardiac injury at both functional and structural levels.

Prospective evaluation of Doppler echocardiography, tissue Doppler imaging and biomarkers measurement for the detection of doxorubicin-induced cardiotoxicity in dogs: A pilot study

The purpose of this pilot study was to evaluate the usefulness of selected echocardiographic parameters, NT-proBNP and cardiac troponin I (cTnI) in the detection of cardiotoxicity in dogs treated with doxorubicin for various malignancies. Echocardiographic studies and biomarker measurements were performed before each administration of doxorubicin, then 1 and 3 months after completion of therapy. Thirteen dogs were included, with a total cumulative dose of doxorubicin ranging from 30 to 150 mg/m(2). E/A ratio significantly decreased during doxorubicin administration (p=0.047). cTnI level was also significantly affected by treatment (p=0.046), increasing above normal at least at one time point in 11 of 13 dogs. The results of this pilot study suggest that monitoring of left ventricular diastolic function and cTnI level measurement might be useful in the early detection of cardiotoxic signs of doxorubicin therapy in dogs.

Diastolic function in anthracycline-treated children

BACKGROUND

Anthracyclines are effective medications for childhood cancer. Their limitation is the risk of cardiomyopathy. Although diastolic dysfunction has been described in patients who received anthracyclines, cardiac monitoring has focused on systolic function, which is abnormal in up to 41% of the patients. We conducted a study to assess diastolic function utilising transmitral inflow Doppler velocities and tissue Doppler imaging in anthracycline-treated children 5 years post-therapy.

METHODS

This was a retrospective study on 63 anthracycline-treated patients. Echocardiographic parameters included peak early and late transmitral inflow Doppler velocities (E, A), E/A ratio, E deceleration time, and tissue Doppler imaging early and late diastolic mitral annulus velocities (E', A'), E/E' ratio, and E'/A' ratio.

RESULTS

All indices of diastolic function that we measured were normal in the anthracycline-treated patients.

CONCLUSION

We conclude that diastolic function assessed by transmitral inflow Doppler velocities and tissue Doppler imaging is normal in anthracycline-treated children 5 years after completion of treatment. Further longitudinal study is needed to determine whether diastolic function becomes abnormal with time in this patient population.

Risks and diagnosis of coronary artery disease in Hodgkin lymphoma survivors

Higher mortality rates are reported because of cardiovascular diseases in individuals living in industrialized areas of the World. In cancer patients, cardiotoxic chemotherapeutic agents and/or mediastinal radiotherapy are additional risk factors for the development of coronary artery disease. An improved survival rate for patients with Hodgkin lymphoma was reported in recent decades. Determining and handling the long-term effects of cancer treatment have become more important nowadays, parallel to the good results reached in survival rates. Mediastinal radiotherapy and cardiotoxic chemotherapeutic agents are routinely used to treat Hodgkin lymphoma but are commonly associated with a variety of cardiovascular complications. Drugs used in cancer treatment and radiotherapy may cause deleterious effects on contractile capacity and conduction system of the heart. Approximately ten years after the completion of all therapies, the cardiovascular disease risk peaks in patients who survived from Hodgkin lymphoma. The value of coronary computed tomography angiography as a diagnostic tool in determining coronary artery disease as early as possible is underlined in this review, in patients who are in remission and carry the risk of coronary artery disease probably because of chemo/radiotherapy used in their treatment. Survivors of Hodgkin lymphoma especially treated with combined chemoradiotherapy at younger ages are candidates for coronary computed tomography angiography.

Speech recognition and frequency of hearing loss in patients treated for cancer in childhood

BACKGROUND

The aim of this study was to characterize the audiological profile accompanying oncological treatment in patients who had cancer in childhood and had been free of oncological treatment for at least 8 years. Our main interest lay in identifying the affected frequencies that interfered with speech intelligibility (SI) in those who had acquired hearing loss after treatment.

PROCEDURE

Two hundred patients who had cancer in childhood were evaluated. Diagnosis was made at the mean age of 6 years old, and hearing evaluation was performed at a mean age of 21 years. Fifty-one of these patients received chemotherapy without cisplatin, carboplatin or head and neck radiotherapy; 64 received cisplatin without head and neck radiotherapy; 75 received head and neck radiotherapy without cisplatin; and 10 received both head and neck radiotherapy and cisplatin chemotherapy. All patients underwent pure tone audiometry and speech audiometry.

RESULTS

Patients who had hearing loss primarily had bilateral symmetric sensorineural hearing loss. Although the average SI for ears with hearing loss in the frequency range from 4 to 8 kHz was normal, the Kruskall-Wallis test showed a significant difference between ears without hearing loss and those with hearing loss between 4 and 8 kHz. The average SI score in ears with hearing loss between 1 and 8 kHz was significantly different from all other ears.

CONCLUSIONS

Hearing loss involving frequencies at and above 4 kHz determines a decline in SI.

Temporal changes in standard and tissue Doppler imaging echocardiographic parameters after anthracycline chemotherapy in women with breast cancer

Anthracyclines are established cardiotoxic agents; however, the exact extent and time course of such cardiotoxicity has not been appraised in detail. We aimed to exploit serial measurements of standard and tissue Doppler imaging (TDI) echocardiographic parameters collected in a prospective clinical trial to clarify the outlook of cardiac function during and long after anthracycline chemotherapy. Women enrolled in a randomized trial focusing on liposomal doxorubicin-based chemotherapy for breast cancer and providing ≥4 separate echocardiographic assessments were included. Repeat-measure nonparametric analyses were used to appraise changes over time in the standard and tissue Doppler imaging echocardiographic parameters. A total of 39 patients with serial imaging evaluations were enrolled. Significant temporal changes were found for the left ventricular ejection fraction and diastolic parameters, despite different temporal trends. Specifically, the left ventricular ejection fraction exhibited a V-shaped trend, decreasing initially from 63% to 61% but then recovering to 64% (p <0.001), with a similar trend in the TDI E/Em ratio (p = 0.011). In contrast, persistent impairments typical of an L-shaped trend were found for the E wave (p = 0.006), TDI lateral Em wave (p = 0.001), and TDI septal Em wave (p = 0.001). In conclusion, subclinical temporal changes in the standard and TDI echocardiographic parameters after anthracycline chemotherapy showed a distinctive pattern of transient impairment followed by full recovery of the left ventricular ejection fraction versus a persistent impairment of the diastolic parameters, which must be taken into account in the everyday treatment of such patients.

Tissue Doppler evaluation of systolic and diastolic cardiac functions in long-term survivors of Hodgkin lymphoma

BACKGROUND

Monitoring for late adverse events is crucial in long-term management of childhood cancer survivors. A case-control study to evaluate long-term cardiovascular status of childhood Hodgkin lymphoma (HL) using tissue Doppler imaging (TDI) was performed.

PATIENTS AND METHODS

Patients diagnosed with HL before age of 18 that completed therapy and were in remission and a control group of healthy children were evaluated by echocardiography and TDI.

RESULTS

Total of 72 HL survivors were included in the study. Median age at diagnosis, remission time, and age at time of echocardiography were 7 (2-16), 9 (2-20), and 17.5 (7-27) years, respectively. TDI revealed decreased S' velocity, reflecting systolic dysfunction in HL survivors, at medial and lateral mitral annuli and at middle segment of interventricular septum (IVS; P < 0.01) for all. Moreover, TDI showed decreased peak E' velocity at medial mitral annulus [12.4 cm/s (5.5-16.3) vs. 13.3 cm/s (10.2-18.9), P = 0.03] and at middle segment of IVS [10 cm/s (5.3-16.3) vs. 11.6 cm/s (6.7-16.7), P < 0.01] and prolongation of isovolemic relaxation time at medial and lateral annuli of the mitral valve (P < 0.01) and at middle segment of IVS (P = 0.03) suggesting diastolic dysfunction in HL survivors.

CONCLUSION

Cardiac dysfunction after childhood cancer therapy may develop after many years. Since systolic and diastolic dysfunction can be seen in these patients periodic echocardiographic screening of both systolic and diastolic function in the survivors of HL might be useful in the follow-up of these patients.