Frequency and management of troponin I elevation in patients treated with molecular targeted therapies in phase I trials

The Value of Troponin as a Biomarker of Chemotherapy-Induced Cardiotoxicity

In cancer survivors, cardiac dysfunction is the main cause of mortality. Cardiotoxicity represents a decline in cardiac function associated with cancer therapy, and the risk factors include smoking, dyslipidemia, an age of over 60 years, obesity, and a history of coronary artery disease, diabetes, atrial fibrillation, or heart failure. Troponin is a biomarker that is widely used in the detection of acute coronary syndromes. It has a high specificity, although it is not exclusively associated with myocardial ischemia. The aim of this paper is to summarize published studies and to establish the role of troponin assays in the diagnosis of cardiotoxicity associated with various chemotherapeutic agents. Troponin has been shown to be a significant biomarker in the diagnosis of the cardiac dysfunction associated with several types of chemotherapeutic drugs: anthracyclines, anti-human epidermal growth factor receptor 2 treatment, and anti-vascular endothelial growth factor therapy. Based on the data available at this moment, troponin is useful for baseline risk assessment, the diagnosis of cardiotoxicity, and as a guide for the initiation of cardioprotective treatment. There are currently clear regulations regarding the timing of troponin surveillance depending on the patient’s risk of cardiotoxicity and the type of medication administered, but data on the cut-off values of this biomarker are still under investigation.

Cardiovascular Imaging in Cardio-Oncology: The Role of Echocardiography and Cardiac MRI in Modern Cardio-Oncology

Cardiovascular (CV) events are an increasingly common limitation of effective anticancer therapy. Over the last decade imaging has become essential to patients receiving contemporary cancer therapy. Herein we discuss the current state of CV imaging in cardio-oncology. We also provide a practical apparatus for the use of imaging in everyday cardiovascular care of oncology patients to improve outcomes for those at risk for cardiotoxicity, or with established cardiovascular disease. Finally, we consider future directions in the field given the wave of new anticancer therapies.

Severe Cardiac Toxicity Induced by Cancer Therapies Requiring Intensive Care Unit Admission

A steadying increase of cancer survivors has been observed as a consequence of more effective therapies. However, chemotherapy regimens are often associated with significant toxicity, and cardiac damage emerges as a prominent clinical issue. Many mechanisms sustain chemotherapy-induced cardiac toxicity: direct myocyte damage, arrhythmia induction, coronary vasospasm, and accelerated atherosclerosis. Anthracyclines are the most studied cardiotoxic drugs and represent a clinical model for cardiac damage induced by chemotherapy. In patients suffering from advanced heart failure (HF) because of chemotherapy-related cardiomyopathy, when refractory to optimal medical therapy, mechanical circulatory support or heart transplantation represents an effective treatment. Here, the main mechanisms of cardiac toxicity induced by cancer therapies are analyzed, with a focus on patients requiring intensive care unit (ICU) admission during the course of the disease because of acute cardiac toxicity, takotsubo syndrome, and acute-on-chronic HF in patients suffering from chemotherapy-induced cardiomyopathy. In a subset of patients, cardiac toxicity can be acute and life-threatening, leading to overt cardiogenic shock. The management of critically ill cancer patients poses a unique challenge and requires a multidisciplinary approach. Moreover, no etiologic therapy is available, and only supportive measures can be implemented.

Clinical and Research Tools for the Study of Cardiovascular Effects of Cancer Therapy

The expansion of cancer therapeutics has paved the way for improved cancer-related outcomes. Cardiotoxicity from cancer therapy occurs in a small but significant subset of patients, is often poorly understood, and contributes to adverse outcomes at all stages of cancer treatment. Given the often-idiopathic occurrence of cardiotoxicity, novel strategies are needed for risk-stratification and early identification of cancer patients experiencing cardiotoxicity. Clinical and research tools extending from imaging to blood-based biomarkers and pluripotent stem cells are being explored as methods to study the cardiovascular impact of various cancer treatments. Here we provide an overview of tools currently available for evaluation of cardiotoxicity and highlight novel techniques in development aimed at understanding underlying pathophysiologic mechanisms.

Role of Cardiovascular Biomarkers in the Risk Stratification, Monitoring, and Management of Patients with Cancer

Cardiovascular effects of cancer therapies are of concern. Prediction, diagnosis, and management of cardiotoxicity is a challenge. Cardiovascular biomarkers are being studied in relationship to cancer therapy, showing promise in detection and prevention of cardiotoxicity. We summarize the use of biomarkers in cardio-oncology and presents recommendations for their use. Troponins and natriuretic peptides are the most commonly used biomarkers. High-quality evidence supporting their use is lacking. Biomarkers can be incorporated into a detection strategy for cardiotoxicity. Large, well-powered studies are needed to delineate care strategies using biomarkers in the prediction and management of the cardiovascular effects of cancer therapy.

Subclinical Left Ventricular Dysfunction During Chemotherapy

Subclinical left ventricular dysfunction is the most common cardiac complication after chemotherapy administration. Detection and early treatment are major issues for better cardiac outcomes in this cancer population. The most common definition of cardiotoxicity is a 10-percentage point decrease of left ventricular ejection fraction (LVEF) to a value <53%. The myocardial injury induced by chemotherapies is probably a continuum starting with cardiac biomarkers increase before the occurence of a structural myocardial deformation leading to a LVEF decline. An individualised risk profile (depending on age, cardiovascular risk factors, type of chemotherapy, baseline troponin, baseline global longitudinal strain and baseline LVEF) has to be determined before starting chemotherapy to consider cardioprotective treatment. To date, there is no proof of a systematic cardioprotective treatment (angiotensin-converting enzyme inhibitor and/or beta-blocker) in all cancer patients. However, early cardioprotective treatment in case of subclinical left ventricular dysfunction seems to be promising in the prevention of cardiac events.

Cardiac Toxicities in the Era of Precision Medicine: Underlying Risk Factors, Targeted Therapies, and Cardiac Biomarkers

Cancer therapies can cause a variety of cardiac toxicities, including ischemia, cardiomyopathy, heart failure, myocarditis, arrhythmias, vascular disease, hypertension, and hyperlipidemia. Addressing cardiovascular risk at baseline, before initiating therapy, during cancer treatment, and in the survivorship period is imperative. It may be useful to risk stratify individuals with cardiovascular risk factors using biomarkers or imaging before they receive potentially cardiotoxic therapies. Additionally, new guidelines recommend cardiac imaging with echocardiography in the survivorship period 6 to 12 months after completing cancer therapy for these high-risk individuals. Close collaboration between cardiology and oncology in both clinical practice and future research is essential.

Role of Biomarkers in Prediction of Cardiotoxicity During Cancer Treatment

Purpose of review

As cancer survivor rates improve with early screening and modern treatment options, cardiotoxicity is becoming an increasing problem. It is imperative for physicians to recognize adverse events early so that appropriate measures can be taken before advanced and permanent cardiac dysfunction ensues. In this review, we will evaluate the literature surrounding current cardiac biomarkers in the detection of cardiotoxicity during cancer treatment as well as discuss the role of emerging novel biomarkers.

Recent findings

Troponin and brain natriuretic peptides show promise in the detection of subclinical cardiotoxicity during cancer treatment. In addition to identifying late complications among cancer survivors, they have the potential to predict patients who are at risk of developing cardiotoxicity prior to the initiation of cancer therapy. However, there are also conflicting data due to varying study design.

Summary

Although biomarkers are an attractive option in the detection of cardiotoxicity among cancer patients, current recommendations surrounding its role are based on expert consensus opinion. Further research with appropriately designed prospective trials is required to guide optimal clinical practice.

Cardiotoxicity with vascular endothelial growth factor inhibitor therapy

Angiogenesis inhibitors targeting the vascular endothelial growth factor (VEGF) signaling pathway (VSP) have been important additions in the therapy of various cancers, especially renal cell carcinoma and colorectal cancer. Bevazicumab, the first VSP to receive FDA approval in 2004 targeting all circulating isoforms of VEGF-A, has become one of the best-selling drugs of all times. The second wave of tyrosine kinase inhibitors (TKIs), which target the intracellular site of VEGF receptor kinases, began with the approval of sorafenib in 2005 and sunitinib in 2006. Heart failure was subsequently noted, in 2-4% of patients on bevacizumab and in 3-8% of patients on VSP-TKIs. The very fact that the single-targeted monoclonal antibody bevacizumab can induce cardiotoxicity supports a pathomechanistic role for the VSP and the postulate of the "vascular" nature of VSP inhibitor cardiotoxicity. In this review we will outline this scenario in greater detail, reflecting on hypertension and coronary artery disease as risk factors for VSP inhibitor cardiotoxicity, but also similarities with peripartum and diabetic cardiomyopathy. This leads to the concept that any preexisting or coexisting condition that reduces the vascular reserve or utilizes the vascular reserve for compensatory purposes may pose a risk factor for cardiotoxicity with VSP inhibitors. These conditions need to be carefully considered in cancer patients who are to undergo VSP inhibitor therapy. Such vigilance is not to exclude patients from such prognostically extremely important therapy but to understand the continuum and to recognize and react to any cardiotoxicity dynamics early on for superior overall outcomes.

Role of biomarkers in monitoring antiblastic cardiotoxicity

Early detection of anticancer drug-induced cardiotoxicity (CTX) has been evaluated by most international scientific cardiology and oncology societies. High expectations have been placed on the use of specific biomarkers. In recent years, conventional biomarkers and molecules of more recent interest have been tested and compared in the context of anticancer drug-related CTX. Encouraging results were obtained from studies on molecules of myocardial damage, such as troponin and markers of myocardial wall stress, including circulating natriuretic peptides, as well as from the assessment of the products of inflammation or circulating levels of free radicals. However, clear guidelines on their sensitivity, specificity, and accuracy are not yet available, and many challenges, such as the optimal time of assessing, optimal schedule for evaluation, optimal cut-off point for positivity with the highest level of specificity, and optimal comparability of different assays for the measurements, remain unresolved. Given the importance of having a reliable and accurate tool for monitoring anticancer drug-induced CTX, this review will focus on the available data on the most effective and widely used biomarkers and the studies that are currently underway that aim to identify the effectiveness of new approaches in this therapeutic setting.

Prevention and Monitoring of Cardiac Dysfunction in Survivors of Adult Cancers: American Society of Clinical Oncology Clinical Practice Guideline

Purpose

Cardiac dysfunction is a serious adverse effect of certain cancer-directed therapies that can interfere with the efficacy of treatment, decrease quality of life, or impact the actual survival of the patient with cancer. The purpose of this effort was to develop recommendations for prevention and monitoring of cardiac dysfunction in survivors of adult-onset cancers.

Methods

Recommendations were developed by an expert panel with multidisciplinary representation using a systematic review (1996 to 2016) of meta-analyses, randomized clinical trials, observational studies, and clinical experience. Study quality was assessed using established methods, per study design. The guideline recommendations were crafted in part using the Guidelines Into Decision Support methodology.

Results

A total of 104 studies met eligibility criteria and compose the evidentiary basis for the recommendations. The strength of the recommendations in these guidelines is based on the quality, amount, and consistency of the evidence and the balance between benefits and harms.

Recommendations

It is important for health care providers to initiate the discussion regarding the potential for cardiac dysfunction in individuals in whom the risk is sufficiently high before beginning therapy. Certain higher risk populations of survivors of cancer may benefit from prevention and screening strategies implemented during cancer-directed therapies. Clinical suspicion for cardiac disease should be high and threshold for cardiac evaluation should be low in any survivor who has received potentially cardiotoxic therapy. For certain higher risk survivors of cancer, routine surveillance with cardiac imaging may be warranted after completion of cancer-directed therapy, so that appropriate interventions can be initiated to halt or even reverse the progression of cardiac dysfunction.

Management and research in cancer treatment-related cardiovascular toxicity: Challenges and perspectives

Cardiovascular toxicity is a potentially serious complication that can result from the use of various cancer therapies and can impact the short- and long-term prognosis of treated patients as well as cancer survivors. In addition to their potential acute cardiovascular adverse events, new treatments can lead to late toxicity even after their completion because patients who survive longer generally have an increased exposure to the cancer therapies combined to standard cardiovascular risk factors. These complications expose the patient to the risk of cardiovascular morbi-mortality, which makes managing cardiovascular toxicity a significant challenge. Cardio-oncology programs offer the opportunity to improve cardiovascular monitoring, safety, and management through a better understanding of the pathogenesis of toxicity and interdisciplinary collaborations. In this review, we address new challenges, perspectives, and research priorities in cancer therapy-related cardiovascular toxicity to identify strategies that could improve the overall prognosis and survival of cancer patients. We also focus our discussion on the contribution of cardio-oncology in each step of the development and use of cancer therapies.

Cancer Therapy-Related Cardiac Dysfunction and Heart Failure: Part 1: Definitions, Pathophysiology, Risk Factors, and Imaging

Advances in cancer therapy have resulted in significant improvement in long-term survival for many types of cancer but have also resulted in untoward side effects associated with treatment. One such complication that has become increasingly recognized is the development of cardiomyopathy and heart failure. Whether a previously healthy person from a cardiovascular perspective develops cancer therapy-related cardiac dysfunction or a high-risk cardiovascular patient requires cancer therapy, the team of oncologists and cardiologists must be better equipped with an evidence-based approach to care for these patients across the spectrum. Although the toxicities associated with various cancer therapies are well recognized, limitations to our understanding of the appropriate course of action remain. In this first of a 2-part review, we discuss the epidemiologic, pathophysiologic, risk factors, and imaging aspects of cancer therapy-related cardiac dysfunction and heart failure. In a subsequent second part, we discuss the prevention and treatment aspects, concluding with a section on evidence gap and future directions. We focus on adult patients in all stages of cancer therapy from pretreatment surveillance, to ongoing therapy, and long-term follow-up.

Cardiotoxicity due to Chemotherapy: the Role of Biomarkers

An ever-increasing array of chemotherapeutic agents is being used in the treatment of solid organ or hematologic malignancies. The success of many of these agents has led to an increasing survival of patients with cancer. However, many of these agents, particularly anthracyclines and trastuzumab, are associated with the development of cardiotoxicity. The current standard for the evaluation of chemotherapy-associated cardiotoxicity typically involves the use of serial measurements of left ventricular (LV) function by echocardiogram (Echo) and radionuclide ventriculogram (MUGA). Unfortunately, this time-honored method offers low sensitivity to the early prediction or detection of cardiac events. Frequently, by the time cardiotoxicity is detected, significant LV dysfunction has occurred and ultimately this may not respond to standard cardioprotective treatment. Cardiac biomarkers, troponin I and B-type natriuretic peptide, may allow a more accurate and timely monitoring strategy. The current data and a summarized understanding of how to utilize cardiac biomarkers for the prevention and early detection of cardiac dysfunction during chemotherapy are presented.

Biomarkers as Predictors of Cardiac Toxicity From Targeted Cancer Therapies

BACKGROUND

Cardiac biomarkers have been extensively investigated as early detectors of cardiac toxicity from cancer therapies. Whereas the role of biomarkers in monitoring anthracycline toxicity is generally well understood, substantial uncertainty remains regarding their role in monitoring newer targeted cancer therapies.

METHODS AND RESULTS

This review article examines all major published studies using cardiac troponins and/or N-terminal pro-B-type natriuretic peptide (NT-proBNP) in monitoring for cardiac toxicity with trastuzumab, tyrosine kinase inhibitors, and mammalian target of rapamycin (mTOR) inhibitors. There is substantial variability among studies regarding biomarker assays used, sensitivity of the assays, and definitions of abnormal results. In general, troponin I predicts early but not late cardiac events when trastuzumab is administered after anthracyclines, but troponin increases likely reflect anthracycline injury rather than trastuzumab injury. NT-proBNP detects cardiac toxicity with tyrosine kinase inhibitors and mTOR inhibitors, but not independently from echocardiography.

CONCLUSIONS

Troponin I can serve as a marker for susceptibility to cardiac toxicity during early trastuzumab treatment in patients who have received recent anthracyclines. NT-proBNP can serve as a useful marker of cardiac toxicity in patients treated with tyrosine kinase inhibitors or mTOR inhibitors if echocardiographic screening is not being used.

Rapid and fatal acute heart failure induced by pazopanib

Tyrosine kinase inhibitors, represented by sunitinib, sorafenib, axitinib and pazopanib, are emerging molecules harbouring antitumoural efficacy in multiple neoplasia. We report the case of a 51-year-old woman with right thoracic sarcoma who developed fatal heart failure on pazopanib. The patient had no cardiovascular risk factor, except previous exposure to anthracycline, and her cardiac function was normally controlled before initiating the pazopanib. Despite a rapid tumour response, fatigue rapidly appeared, requiring treatment interruption 2 weeks after pazopanib introduction. After clinical improvement, the pazopanib was reintroduced at reduced dose; however, a few days later, our patient was admitted for worsening dyspnoea and fatigue. Pulmonary embolism was excluded as was pleuropericardial effusion. Brain natriuretic peptide was the only laboratory abnormality, and echocardiography revealed acute and severe heart failure. The patient died despite pazopanib arrest and inotropic support.

Cardiac complications of chemotherapy: role of biomarkers

OPINION STATEMENT

Both conventional and novel antineoplastic drugs may cause damage to the heart, ultimately affecting patients' survival and quality of life. In fact, the most frequent and typical clinical manifestation of cardiotoxicity, asymptomatic or symptomatic left ventricular dysfunction, may be induced not only by conventional cancer therapy, like anthracyclines, but also by new antitumoral targeted therapy such as trastuzumab. At present, left ventricular ejection fraction assessment represents the main standard practice for cardiac monitoring during cancer therapy, but it detects myocardial damage only when a functional impairment has already occurred, not allowing for early preventive strategies. In the last decade, a newer approach based on the measurement of cardiospecific biomarkers has been proposed, proving to have higher prognostic value than imaging modalities. In particular, cardiac troponin elevation during chemotherapy allows us to identify patients who are more prone to develop myocardial dysfunction and cardiac events during follow up. In these patients, the use of an angiotensin-converting enzyme inhibitor, such as enalapril, has shown to be effective in improving clinical outcome, giving the chance for a cardioprotective strategy in a selected population.

The utility of serum biomarkers to detect myocardial alterations induced by Imatinib in rats

BACKGROUND

Imatinib (Imb) is a tyrosine kinase inhibitor with cardiotoxic activity (decreases in left ventricular function and congestive heart failure) in patients. Currently, clinical diagnosis of Imb cardiotoxicity relies primarily on evaluation of left ventricular function, Imb also induces cardiac lesions in rats.

AIMS

This study, in rats, sought to determine whether monitoring biochemical markers would be a sensitive means to detect Imb-induced changes in cardiomyocyte morphology.

MATERIALS AND METHODS

Groups of male Sprague-Dawley rats were dosed orally with 50, 100, 200 mg kg(-1) Imb or water daily for 28 days. Tissues and blood samples were collected 24 h after the last dosing. Cardiac biomarkers such as cardiac troponin I (cTnI), cardiac troponin T (cTnT), and fatty acid binding protein 3 (FABP3) were monitored by the Erenna, Elecsys, and Meso Scale immunoassay systems.

RESULTS

Imb caused microscopic myocardial lesions (myofibrillar loss, cytoplasmic vacuolization, and necrosis) at all doses as determined by unbiased histopathology analysis. The severity of the alterations was dose-related with mean lesion scores (based on a scale of 0-3) of 1.2 (50 mg kg(-1)), 2.1 (100 mg kg(-1)) and 2.9 (200 mg kg(-1)). However, the increases in cTnI, cTnT, and FABP3 levels were noted primarily in high-dose Imb treated animals.

DISCUSSION AND CONCLUSION

The occurrence of myocardial alterations in animals without consistent changes in cardiac troponin and FABP3 concentrations raises questions regarding the utility of these biomarkers as early indicators of Imb-induced cardiotoxicity. Due to limited numbers of animals the reasons for this discrepancy could not be determined.

Using cardiac biomarkers and treating cardiotoxicity in cancer

Cardiotoxicity is a frequent and serious adverse effect of both conventional and novel anticancer treatments, affecting patient survival and quality of life. The current standard for cardiac monitoring during cancer therapy, mainly based on left ventricular ejection fraction assessment, detects myocardial damage only when a functional impairment has already occurred, not allowing for early preventive strategies. Measurement of cardiospecific biomarkers has proven to have higher prognostic value than imaging modalities. In particular, cardiac troponin elevation during chemotherapy allows the identification of patients who are more prone to develop myocardial dysfunction and cardiac events during follow-up. In these patients, the use of an angiotensin-converting enzyme inhibitor such as enalapril has shown to be effective in improving clinical outcome, giving the chance for a cardioprotective strategy in a selected population. Once left ventricular dysfunction occurs, heart failure therapies currently used for other forms of left ventricular dysfunction, particularly angiotensin-converting enzyme inhibitors and β-blockers, seem to be effective. However, their use in cancer patients is still undervalued.

Effects of tyrosine kinase inhibitors on rat isolated heart function and protein biomarkers indicative of toxicity

INTRODUCTION

Cardiac toxicity, manifested as diminished contractility, ischemic heart disease, and heart failure is a major issue in drug safety. Concerns revolve around targeted drugs (TKIs) where contractility effects were not anticipated. The ability to predict cardiac toxicity early would help to de-risk drugs in development and prepare physicians to manage risk in the clinic. Issues with current preclinical studies include insufficient testing with informative, translatable models, and predictive biomarkers. The isolated heart model is amenable to multiple assessments which can be combined with current technologies to assess toxicity on a multi-scale level.

METHODS

Rat isolated heart model was used to assess changes in left ventricular (LV) contractility and protein biomarkers BNP, IL6, TNFα, and cardiac troponins T (TnT) and I (TnI). Responses were assessed during perfusion with modified Henseleit Krebs (MHK), and 20 min concentration escalations of verapamil, carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), isoproterenol, or 20 min escalations bracketing clinical blood concentrations of sunitinib, sorafenib, and erlotinib. LV parameters and effluent for biomarkers were collected before and during escalating drug concentrations.

RESULTS

Verapamil reduced inotropy with no change in biomarkers, FCCP and isoproterenol reduced and increased heart function respectively and increased TnT and TNFα. Erlotinib had no significant effects on function or biomarkers. Sunitinib diminished function, increased TNFα at 0.1 μM, and increased TnT at higher concentrations. Sorafenib dose dependently increased TNFα beginning at 0.1 μM, reducing contractility and flow rate at 0.6 μM.

DISCUSSION

The ex-vivo assay is a sensitive and predictive model for assessing changes in heart function and biomarkers of toxicity and injury. This assay demonstrates the potential for sunitinib and sorafenib to cause cardiac toxicity in humans. Also, TNFα appears to be a biomarker in the heart prior to injury. Due to its versatility, the isolated heart assay has potential to fill gaps in cardiac safety testing early in drug development.

Cardiovascular toxicity of tyrosine kinase inhibitors

INTRODUCTION

Small-molecule tyrosine kinase inhibitors (TKIs) have revolutionized the management of many malignancies. However, they also have been shown to be associated with a certain degree of cardiovascular side effects that are often reversible.

AREAS COVERED

As the number of new TKIs continues to grow, it is expected that clinicians will be facing the challenge of early detection and 10 management of these side effects while balancing the risk-benefit ratios of continuing with life-saving cancer therapy medications. This review will present the current knowledge related to incidence and proposed mechanisms of cardiovascular side effects of TKIs and also discuss treatment recommendations when available

EXPERT OPINION

We will present and discuss available data and suggest recommendations related to patient monitoring and early identification of TKIs related cardiovascular toxities.

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.