Serum N-terminal atrial natriuretic peptide (NT-ANP) in the cardiac follow-up in children with cancer

Elevations in High-Sensitive Cardiac Troponin T and N-Terminal Prohormone Brain Natriuretic Peptide Levels in the Serum Can Predict the Development of Anthracycline-Induced Cardiomyopathy

BACKGROUND

Anthracyclines remain the cornerstone of the treatment in many cancers including lymphomas, leukemia and sarcomas, and breast cancer. The cardiomyopathy that develops from anthracyclines can lead to heart failure and decreased survival. Multiple mechanisms are involved in the pathophysiology of anthracycline-induced heart failure.

STUDY QUESTION

We hypothesize that anthracycline-induced cardiac (AIC) pathology can be monitored using a panel of blood biomarkers including high-sensitive cardiac troponin T (hs-cTnT) for myocyte necrosis and N-terminal prohormone brain natriuretic peptide (NT-proBNP) for parietal stress.

STUDY DESIGN

A prospective, institutionally approved study recruited all patients with cancer scheduled to start anthracycline chemotherapy in the Transylvania University cancer clinics.

MEASURES AND OUTCOMES

Transthoracic 2D echocardiography and the measurements of NT-proBNP and hs-cTnT plasma levels were performed at the beginning of the study and 3 months and 6 months after anthracycline treatment initiation.

RESULTS

The plasma levels of hs-cTnT at 3 months (rho = 0.439, P = 0.0001) and 6 months (rho = 0.490, P = 0.0001) are correlated with AIC occurrence. For a cutoff value of hs-cTnT at 3 months > 0.008 ng/mL, we obtained 66.7% sensitivity and 67.9% specificity for developing AIC at 6 months, with a 54.5% positive predictive value and a 87.8% negative predictive value. The NT-proBNP serum levels at 3 months (rho = 0.495, P = 0.0001) and 6 months (rho = 0.638, P = 0.0001) are correlated with an AIC diagnosis at 6 months. For a cutoff value of NT-proBNP at 3 months >118.5 pg/mL, we obtained 80% sensitivity and 79.2% specificity for evolution to AIC at 6 months, with 52.2% positive predictive value and 93.3% negative predictive value.

CONCLUSIONS

In anthracycline-treated cancer patients, the increase in plasma levels of NT-proBNP and of hs-cTnT can predict the development of anthracycline-induced cardiomyopathy. Early identification of at-risk patients will potentially allow for targeted dose reductions and will diminish the number of patients developing cardiac pathology.

Can we find a good biochemical marker of early cardiotoxicity in children treated with haematopoietic stem cell transplantation?

Cardiotoxicity is one of the complications following haematopoietic stem cell transplantation (HSCT), but its diagnosis may be hampered due to the presence of different post-transplant comorbidities. The aim of the study was to assess the incidence of cardiac complications and the significance of biochemical markers (NT-proBNP, ANP, ET-1, and TnI) and ECHO systolic and diastolic parameters analysis in children treated with HSCT. Thirty consecutive children (median age 9.6 years) were included in the study. The control group consisted of 14 healthy children (median age of 10.9 years). None of the transplanted children developed clinical cardiotoxicity. Median ET-1 and NT-proBNP plasma levels were elevated when compared to controls in at least 3 out of 4 analysed time points, median ANP levels differed only in one time point, and no difference was found between median TnI values in all analysed time points. Echocardiographic systolic parameters were within the normal range, while median E/A ratio assessed before HSCT, on day +30, and +100 post-transplant was statistically lower in HSCT patients (respectively, 1.34, 1.37, and 1.42 vs. 1.73). It confirms the need for careful follow up in patients who have received chemotherapy and have been treated with HSCT.

Cardiotoxicity of childhood cancer treatment: update and current knowledge on long-term follow-up

Therapeutic advances in paediatric oncology allowed increasing numbers of children to survive until adulthood. However, chemotherapy and radiotherapy are potentially cardiotoxic and contribute to a significant morbidity and mortality, cardiovascular events remaining the leading cause of death among survivors. This review summarizes the physiopathology of treatment-related cardiovascular diseases, their incidence, and the risk factors associated with each specific therapy. Few studies have investigated the cardiac outcomes of adult surviving from childhood cancers but all demonstrated a substantial risk for late cardiac effects. Cardiovascular monitoring, prevention, and early detection of cardiac dysfunction are, therefore, the keystones of an improved long-term outcome.

Assessment of cardiotoxicity with cardiac biomarkers in cancer patients

Cardiotoxicity remains a major limitation of chemotherapy, strongly affecting the quality of life and the overall survival of cancer patients, regardless of their oncologic prognosis. The time elapsed from the end of cancer therapy to the beginning of heart failure therapy for chemotherapy-induced cardiac dysfunction is an important determinant of the extent of recovery. This highlights the need for a real-time diagnosis of cardiac injury. The current standard for monitoring cardiac function detects cardiotoxicity only when a functional impairment has already occurred, precluding any chance of preventing its development. In the last decade, early identification, assessment, and monitoring of cardiotoxicity, by measurement of serum cardiospecific biomarkers, have been proposed as an effective alternative. In particular, the role of troponin I in identifying patients at risk for cardiotoxicity and of angiotensin-converting enzyme inhibitors in preventing left ventricular ejection fraction reduction and cardiac events has clearly proved to be an effective strategy for this complication. In addition, novel biomarkers for the identification of cardiotoxicity are emerging. The use of a multimarker approach may provide a unique opportunity for advancement in this field, allowing for better stratification of the cardiac risk in cancer patients treated with anticancer drugs.

Plasma natriuretic peptides levels and echocardiographic findings in late subclinical anthracycline toxicity

The purpose of this study was to evaluate late cardiac toxicity by comprehensive echocardiographic study, and to determine whether plasma atrial natriuretic peptide and brain natriuretic peptide levels might be indicators of neurohumoral activation. The study included 49 long-term survivors and 21 controls. A wide variety of echocardiographic parameters were measured or calculated. Plasma peptide levels were determined. Patients had significant changes in different echocardiographic parameters that are suggestive of LV systolic and diastolic dysfunction. Plasma peptide levels were not increased. The authors have found significant subclinic cardiotoxicity by echocardiography. Survivors seem to have normal plasma natriuretic peptide levels in long-term period.

Troponins and natriuretic peptides in the monitoring of anthracycline cardiotoxicity

Anthracycline-related cardiotoxicity has a substantial negative impact on long-term survivors of childhood cancer. The detection of cardiotoxicity is currently based on echocardiography or radionuclide angiography. However, as they depict only the final outcome of myocardial injury in terms of reduced heart contractility, heart specific biomarkers of myocardial destruction or dysfunction could be advantageous by allowing for an earlier detection of cardiotoxicity. In the present study, the usefulness of cardiac troponins and natriuretic peptides, the most commonly used biomarkers of myocardial destruction and ventricular dysfunction respectively, to detect and to predict the development of anthracycline cardiotoxicity has been reviewed.

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.

Anthracycline cardiotoxicity

The use of anthracyclines is limited by dose-dependent cardiotoxicity. Three forms of anthracycline cardiotoxicity are described; an immediate pericarditis-myocarditis syndrome, an early onset chronic progressive CHF developing during or shortly after therapy and late-onset cardiotoxicity presenting years following treatment. A number of risk factors have been reported, including; cumulative dose, administration schedule, mediastinal radiotherapy, old and young age, concurrent cardiovascular disease, combination therapy, gender, ethnicity and chromosomal abnormalities. Evaluation of left ventricular ejection fraction has been widely adopted as a means of monitoring and assessing anthracycline-induced cardiotoxicity. Biochemical markers and other techniques, such as endomyocardial biopsy, metaiodobenzylguanidine and indium-111-antimyosin scintigraphy are not routinely used. Methods employed to prevent cardiotoxicity include cumulative dose limitation, alteration of administration schedule, anthracycline analogues, liposomal formulations and the cardioprotective agent, dexrazoxane. With the growing number of paediatric malignancy survivors and the increasing use of anthracyclines in the adjuvant treatment of breast cancer, the cardiotoxicity associated with these agents will remain a formidable issue for physicians. Further work is required to identify patients at increased risk of cardiotoxicity and to develop novel methods of protecting and treating this adverse effect.

Correlation of plasma N-terminal pro-brain natriuretic peptide levels with left ventricle mass in children treated with anthracyclines

BACKGROUND

The incidence of subclinical cardiotoxicity following anthracycline treatment for childhood cancer varies according to the method used for its detection. The aim of the study was to document the prevalence of left ventricular myocardial mass (LVM) reduction and its possible association with plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in asymptomatic children treated with anthracyclines.

PATIENTS AND METHODS

Nineteen asymptomatic children who had received anthracyclines during their treatment for cancer were evaluated. They had received an equivalent of doxorubicin dose 240 mg/m2 (22-1200 mg/m2) on average 3.9 years (0.6-8.3) before (median age at diagnosis 3.8 years). The LVM was determined by M-Mode echocardiography and compared to the expected value, obtained from the regression equation of LVM on height of a group of 160 healthy children. Additionally the patients' plasma NT-pro BNP levels were determined.

RESULTS

A high prevalence of reduced LVM associated with increased NT-proBNP levels was found. The average LVM value was -14.4% (+/-4.9) lower than expected whereas fourteen patients (73%) had a lower LVM than predicted. The NT-pro BNP levels in patients with reduced LVM were significantly higher than those measured in patients without LVM reduction (0.316+/-0.02 versus 0.17+/-0.01 pmol/ml respectively, p=0.009). A cut off NT-pro BNP level of 0.2 pmol/ml could differentiate patients with LVM reduction from those with normal or greater than expected LVM.

CONCLUSION

The association of higher NT-proBNP levels with reduced LVM in asymptomatic children after anthracycline administration could be an early indication of subclinical cardiotoxicity.

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.

Natriuretic peptides in the monitoring of anthracycline induced reduction in left ventricular ejection fraction

BACKGROUND

The use of anthracyclines in treatment of cancer is limited by cardiotoxicity of these compounds and may lead to heart failure. Therefore monitoring of cardiac function is necessary during therapy.

AIM

We evaluated the value of natriuretic peptides (N-terminal pro-atrial natriuretic peptide (N-ANP) and brain natriuretic peptide (BNP)) for monitoring and predicting anthracycline induced cardiotoxicity using radionuclide left ventricular ejection fraction (EF) measurements as reference.

METHODS AND RESULTS

A total of 107 consecutive patients receiving anthracycline as part of their chemotherapy for malignant disease were studied. Plasma concentrations of the peptides were measured by radioimmunoassay and EF by radionuclide cardiography. For reduced EF values, i.e. below 0.50 a fairly strong correlation was found between N-ANP or BNP and EF. Of 48 patients with serial EF and peptide measurements, 19% showed a significant EF decrease (>0.10) and ended with a final EF value below 0.50. Baseline EF was no predictor of a change in EF during treatment. Neither baseline levels of N-ANP or BNP nor a change in the same variables during therapy were predictive of a change in EF.

CONCLUSIONS

In spite of correlations between peptide concentrations and reduced EF values neither baseline values nor serial measurements can safely substitute EF monitoring in patients undergoing anthracycline therapy.

The potential cardioprotective effects of amifostine in irradiated rats

PURPOSE

The aim of this study is to determine the cardioprotective efficacy of amifostine. The study consists of researching the relationship between plasma brain natriuretic peptide levels and the electrical and morphologic changes in irradiated rats with or without amifostine.

METHODS AND MATERIALS

Sixty Wistar albino rats were divided into 4 groups, and their hearts were given 15 Gy/fraction with (60)Co. In Groups I and II, the rats were killed after 24 hours to detect early effects; in Groups III and IV, the rats were killed 100 days after irradiation to detect late effects. Before irradiation, Groups I and III received 0.9% saline solution, whereas Groups II and IV received amifostine (200 mg/kg). Twenty rats were used as a control group.

RESULTS

On the 100th day, mild myocardial degeneration was detected in 5 rats (33%) from Group III (no amifostine). This percentage was statistically different from that of Group IV (treated with amifostine) and the controls (p = 0.042). There was no statistically significant difference between the mean plasma brain natriuretic peptide values of the groups (p > 0.05). There was no significant difference in electrocardiographies between the groups. There was no correlation between continuous variables.

CONCLUSION

In the amifostine group (IV) on the 100th day, there was no myocardial degeneration, suggesting that amifostine has a cardioprotective effect.

Long-term prospective follow-up study of cardiac function after cardiotoxic therapy for malignancy in children

PURPOSE

To evaluate cardiac function by means of conventional and three-dimensional echocardiography (3DE) and measurement of natriuretic peptides in children and adolescents previously treated for childhood malignancy using individual follow-up data and matched control children as reference criteria.

PATIENTS AND METHODS

Thirty-nine survivors of childhood malignancy were examined in 1994 and 1998. The mean time from the diagnosis was 8.6 (3.9 to 16.8) years and between cardiac evaluations was 4.1 (3.3 to 5.1) years. Patients were divided into two groups according to therapies given (group I (n = 30): no cardiac irradiation, median cumulative anthracycline dose 210 mg/m2; group II (n = 9): irradiation in the cardiac region, median cumulative anthracycline dose 180 mg/m2).

RESULTS

Fractional shortening (FS) in 1994 was higher than in 1998 (32.5 +/- 4.3 vs. 30.3% +/- 3.3%, P =.009). 33% of patients in group I and 56% in group II in 1994 and 30% of patients in group I and 67% in group II in 1998 had N-terminal of the propeptide-atrial natriuretic peptide (NT-proANP) levels exceeding the 90th percentile of controls. In 1998, both groups (I and II) had lower ejection fraction (EF) measured by 3DE than their matched controls (52.9 +/- 5.2 vs. 58.8% +/- 3.1%, P <.001 and 50.0 +/- 6.6 vs. 60.8% +/- 3.2%, P =.024, respectively). Left atrial maximum volumes/body surface area were smaller in the patients than in controls. B-Type natriuretic peptide values did not differ significantly in either group.

CONCLUSION

Left ventricular contractility decreases slowly even years after cardiotoxic cancer therapy in children. 3DE and NT-proANP measurements are effective methods to evaluate the cardiac function in these patients.

Cardiac status in bone tumor survivors up to nearly 19 years after treatment with doxorubicin: a longitudinal study

BACKGROUND

Longitudinal assessment of cardiac toxicity in anthracycline-treated long-term bone tumor survivors.

PROCEDURES

Cardiac status was assessed in 29 patients 14.1 (range 7-18.7) years after treatment with doxorubicin (DOXO) 360 mg/m(2) (median 225-550). The median age of the patients at the time of the study was 32.5 years (range 19.7-52). The evaluation consisted of an electrocardiogram (ECG), 24-hr ambulatory ECG with analysis of heart rate variability (HRV) and echocardiography. The results were compared to those of a study of the same patients that was performed 5 years earlier 8.9 years (range 2.3-14.1) after treatment. [Postma et al.: Med Pediatr Oncol 26:230-237, 1996]

RESULTS

We found no progression of ECG abnormalities, arrhythmias, or echocardiographic abnormalities. Females were at risk for reduced contractility (P = 0.006). HRV was significantly reduced compared to age- and sex-matched controls and compared to the previous results.

CONCLUSIONS

Anthracycline-related late echocardiographic abnormalities and arrhythmias detected 8.9 years after treatment, showed no further deterioration with ongoing follow-up. However, there was a significant reduction of HRV. This suggests that HRV might be a sensitive test for detection of anthracycline-induced cardiac toxicity.

Chemotherapy-induced cardiotoxicity: current practice and prospects of prophylaxis

Cardiotoxicity is a potential side effect of few chemotherapeutic agents. The anthracycline class of cytotoxic antibiotics are the most famous, but other chemotherapeutic agents can also cause serious cardiotoxicity and are not so well recognised. Examples include cyclophosphamide, ifosfamide, mitomycin and fluorouracil. Prediction and hence prophylaxis has always been a difficult task. Ideal monitoring techniques, upon which efficient prophylaxis depends, are yet to be determined. Current prophylaxis relies upon early detection of systolic and/or diastolic dysfunction. While somewhat useful, in some cases by the time defects are detected progression of chemotherapy-induced cardiomyopathy is beyond prevention. Prophylaxis would be much more efficient if a biochemical marker of myocardiocyte damage could be reliably used to stop further chemotherapy at the correct time before irreversible progressive 'macroscopic' damage becomes evident upon imaging. Work is currently progressing to identify the role of markers such as troponins and natriuretic peptides in this regard.

Plasma levels of natriuretic peptides in relation to doxorubicin-induced cardiotoxicity and cardiac function in children with cancer

BACKGROUND

Anthracyclines are effective anticancer drugs for childhood cancer with dose-limiting cardiotoxicity. Children who have received anthracyclines thus need periodical cardiac evaluation. The plasma levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) have been shown to increase in proportion to severity of cardiac dysfunction. We examined whether plasma levels of ANP and BNP, in addition to echocardiographic evaluation, can be used as specific markers for doxorubicin-induced cardiotoxic effects in children.

PROCEDURE

Consecutively, 34 patients (18 boys and 16 girls) who had previously received doxorubicin-containing chemotherapy were enrolled in this study. Plasma ANP and BNP were assayed simultaneously at the time of first cardiac function evaluation by echocardiography.

RESULTS

Of the 34 patients, 8 (23.5%) had left ventricular dysfunction as assessed by echocardiography. Both ANP and BNP plasma levels in these patients were significantly elevated in comparison with healthy controls (P < 0.01) or patients with normal cardiac function (P < 0.05). It should be also noted that ANP and BNP levels were correlated significantly with cardiac systolic function, but not with diastolic function.

CONCLUSIONS

These results suggest that plasma ANP and BNP levels could be markers for doxorubicin-induced cardiotoxicity in children. Measurement of natriuretic peptide levels during treatment may allow earlier-identification of individuals at risk for severe cardiac damage.

Detection of anthracycline-induced cardiotoxicity

The use of anthracyclines, a group of potent anti-cancer agents incorporated into the treatment of a wide variety of solid and haematological tumours, is limited by its cardiotoxicity that can result in congestive heart failure (CHF). The best method to detect cardiotoxicity at an early stage in order to prevent severe deterioration, is still an unsolved problem. Although endomyocardial biopsy is considered to be the most sensitive and specific test for this purpose, its use is limited by its invasiveness. In daily practice, oncologists make use of parameters of systolic function (left ventricular ejection fraction, or fractional shortening) to detect cardiotoxicity, but these methods are not able to identify cardiotoxicity at an early stage. Based on increasing knowledge into the pathophysiology of anthracycline-induced cardiotoxicity and heart failure in general, new methods including the determination of diastolic function parameters, anti-myosin scintigraphy, assessment of heart rate variability, and the determination of biochemical markers have been proposed to identify patients at risk of the development of CHF in an early stage. However, most of these newer methods have not yet been adequately evaluated to allow them to be recommended for use in routine clinical practice.