The Future Role of Cardio-oncologists

Early Detection of Cardiotoxicity From Systemic and Radiation Therapy in Patients With Breast Cancer: Protocol for a Multi-Institutional Prospective Study

Background

The incidence of breast cancer is rising worldwide. Recent advances in systemic and local treatments have significantly improved survival rates of patients having early breast cancer. In the last decade, great attention has been paid to the prevention and early detection of cardiotoxicity induced by breast cancer treatments. Systemic therapy-related cardiac toxicities have been extensively studied. Radiotherapy, an essential component of breast cancer treatment, can also increase the risk of heart diseases. Consequently, it is important to balance the expected benefits of cancer treatment with cardiovascular risk and to identify strategies to prevent cardiotoxicity and improve long-term outcomes and quality of life for these patients.

Objective

This CardioTox Breast study aims to investigate the use of cardiac imaging, based on cardiac magnetic resonance and echocardiography, and to identify associated circulating biomarkers to assess early tissue changes in chemo-induced and radiation-induced cardiotoxicity in the time window of 12 months after the end of radiotherapy in patients with breast cancer.

Methods

The CardioTox Breast trial is a multicenter observational prospective longitudinal study. We aim to enroll 150 women with stage I-III unilateral breast cancer, treated with breast conserving surgery, who planned to receive radiotherapy with or without systemic therapy. Baseline and follow-up data include cardiac measurements based on cardiac magnetic resonance imaging, echocardiography, and circulating biomarkers of cardiac toxicity.

Results

This study details the protocol of the CardioTox Breast trial. Recruitment started in September 2020. The results of this study will not be published until data are mature for the final analysis of the primary study end point.

Conclusions

The CardioTox Breast study is designed to investigate the effects of systemic and radiation therapy on myocardial function and structure, thus providing additional evidence on whether cardiac magnetic resonance is the optimal screening imaging for cardiotoxicity.

Trial Registration

ClinicalTrials.gov NCT04790266; https://clinicaltrials.gov/ct2/show/NCT04790266

International Registered Report Identifier (IRRID)

DERR1-10.2196/31887

In-hospital mortality, length of stay and hospital costs for hospitalized breast cancer patients with comorbid heart failure in the USA

OBJECTIVES

Breast cancer and heart failure (HF) are frequently interconnected due to shared risk factors and the cardiotoxicity of breast cancer treatment. However, the association between HF and hospital outcomes among breast cancer patients has not been studied. This study examined the association between HF and hospital outcomes among hospitalized patients with breast cancer.

METHODS

This cross-sectional study using the 2015-2018 Healthcare Cost and Utilization Project-National Inpatient Sample data included hospitalized women who were aged 18 years or older and had a primary diagnosis code for breast cancer. Logistic regression, negative binomial regression, and generalized linear models with log-link and gamma distribution were used to assess the associations of HF with in-hospital mortality, length of stay (LOS) and hospital costs.

RESULTS

Among 17,335 hospitalized patients with breast cancer, 4.2% (n = 1021) had HF. Compared to breast cancer patients without HF, those with HF were more likely to die during hospitalization (odds ratio = 1.65, 95% CI = 1.27-2.16, p < .001), stay in the hospital longer (incidence rate ratio = 1.22, 95% CI = 1.15-1.30, p < .001) and have higher hospital costs (cost ratio = 1.09, 95% CI = 1.03-1.14, p = .003) during hospitalization, controlling for covariates.

CONCLUSION

HF has a substantial negative impact on health outcomes among hospitalized breast cancer patients. Breast cancer and HF are often considered separate medical conditions, but promoting effective management of comorbid HF in breast cancer patients may help to improve hospital outcomes in this population.

The Growing Impact of Cardiovascular Oncology: Epidemiology and Pathophysiology

Progress in the treatment of cancer has significantly improved survival of oncologic patients in recent decades. However, anticancer therapies, particularly some new, more potent and targeted agents, are potentially cardiotoxic. As a consequence, cardiovascular complications, including heart failure, arterial hypertension, coronary artery disease, venous thromboembolism, peripheral vascular disease, arrhythmias, pericardial disease, and pulmonary hypertension, as related to cancer itself or to anticancer treatments, are increasingly observed and may adversely affect prognosis in oncologic patients. Cardiovascular oncology is an emerging field in cardiology and internal medicine, which is rapidly growing, dealing with the prevention, the early detection, and the management of cardiovascular disease, in all stages of anticancer therapy and during the survivorship period, now crucial for reducing cardiovascular morbidity and mortality in cancer patients. In this narrative review, the existing literature regarding the epidemiology of cardiovascular oncology, the mechanisms of cardiovascular complications in cancer, and the pathophysiology of cardiotoxicity related to chemotherapeutic agents, targeted therapies, immunotherapies, and radiotherapy will be analyzed and summarized.

Nuclear imaging of chemotherapy-induced cardiotoxicity

The high efficiency of modern chemotherapy has made it possible to achieve great success in the treatment of cancer. Cardiovascular adverse effects are a major disadvantage of anticancer therapy, often requiring low and less effective doses or even drug withdrawal. Nuclear imaging techniques are the most sensitive in early detection of left ventricular damage and dysfunction during chemotherapy. This review presents modern data on the potential of nuclear imaging of cardiotoxicity.

Healthcare disparities in cardio oncology: patients receive same level of surveillance regardless of race at a safety net hospital

Background

Cardiotoxicity remains a dreaded complication for patients undergoing chemotherapy with human epidermal growth factor (HER)-2 receptor antagonists and anthracyclines. Though many studies have looked at racial disparities in heart failure patients, minimal data is present for the cardio-oncology population.

Methods

We queried the echocardiogram database at a safety net hospital, defined by a high proportion of patients with Medicaid or no insurance, for patients who received HER2 receptor antagonists and/or anthracyclines from January 2016 to December 2018. Patient demographics, clinical characteristics, and treatment outcomes were collected. Based on US census data in 2019, home ZIP codes were used to group patients into quartiles based on median annual household income. The primary end point studied was referral rate to cardiology for patients undergoing chemotherapy.

Results

We identified 149 patients who had echocardiograms and also underwent treatment with HER2 receptor antagonists and/or anthracyclines, of which 70 (47.0%) were referred to the cardio-oncology program at our institution. Basic demographics were similar, but white patients were more likely to live in ZIP codes with higher income quartiles (p < 0.00001). Comparing between racial groups, there was no statistical difference in the percentage of patients that had a reduction in ejection fraction (EF) (p = 0.75). There was no statistical difference between racial groups in the number of cardiology or oncology appointments attended, number of appointments cancelled, average number of echocardiograms received, additional cardiac imaging received. Black patients were more likely to receive ACEI/ARB post chemotherapy (p = 0.047). A logistic regression model was created using race, age, gender, insurance, income quartile by home ZIP code, comorbidities (hypertension, hyperlipidemia, coronary artery disease, arrhythmia, diabetes mellitus, smoking, family history, age > 65), procedures (coronary stents, cardiac surgery), medications pre-chemotherapy, cancer type, cancer stage, and chemotherapy. This model found that there was an increased referral rate among patients from higher income quartiles (p = 0.017 for quartile 3, p = 0.049 for quartile 4), patients with a history of hypertension (p < 0.0001), and patients with breast cancer (p = 0.02).

Conclusions

The results of this study suggest that patients of our cardio-oncology population at a safety net hospital receive the same level of surveillance and treatment, and develop drop in ejection fraction at similar rates regardless of their race. However, patients that reside in ZIP codes associated with higher income quartiles, with hypertension, and with breast cancer, are associated with increased rate of referral.

Impact of hypertension on left ventricular function in patients after anthracycline chemotherapy for malignant lymphoma

BACKGROUND

Hypertension is considered an important risk factors for cancer therapeutics-related cardiac dysfunction (CTRCD) as well as heart failure. However, the impact of hypertension and left ventricular (LV) hypertrophy (LVH), which is associated with hypertension, on LV function in patients treated with anthracycline chemotherapy for malignant lymphoma remains uncertain.

METHOD

We studied 92 patients with malignant lymphoma and with preserved LV ejection fraction (LVEF). Echocardiography was performed before and two-month after anthracycline chemotherapy. CTRCD was defined as the presence of an absolute decrease in LVEF ≥10% to a final value <53%. LVH was defined as concentric hypertrophy, which was determined as relative wall thickness ≥ 0.42 and LV mass index >95 g/m² for females and > 115 g/m² for males.

RESULTS

Relative decrease in LVEF after anthracycline chemotherapy in patients with hypertension (n = 23) was significantly higher than that in patients without hypertension (n = 69) (-5.8% [-9.4, -1.3]) vs. (-1.1% [-4.1, 2.5]); P = .005). Moreover, the prevalence of CTRCD in patients with hypertension tended to be higher than in those without hypertension (17% vs. 5%, p = .09). A sequential logistic model for predicting CTRCD, based on baseline clinical variables including major clinical risk factors, was improved by the addition of the complication of hypertension (P = .049), and further improved by the addition of the presence of LVH (P = .023).

CONCLUSIONS

Hypertension, especially when complicated by LVH, was found to be associated with LV dysfunction after anthracycline chemotherapy in patients with malignant lymphoma and preserved LVEF. Watchful observation or early therapeutic intervention may thus be needed for such patients by the addition of the presence of LVH.

Physiological monitoring in the complex multi-morbid heart failure patient - Introduction

Repeated physiological monitoring of comorbidities in heart failure (HF) is pivotal. This document introduces the main challenges related to physiological monitoring in the complex multimorbid HF patient, arising during an ESC consensus meeting on this topic.

Teaching the basics of the mechanism of doxorubicin-induced cardiotoxicity: Have we been barking up the wrong tree?

Doxorubicin (DOX), or Adriamycin, an anthracycline antibiotic discovered serendipitously as a chemotherapeutic drug several decades ago, is still one of the most effective drugs for treating various adult and pediatric cancers (breast cancer, Hodgkin's disease, lymphoblastic leukemia). However, one of the major side effects of the continuous use of DOX is dose-dependent, long-term, and potentially lethal cardiovascular toxicity (congestive heart failure and cardiomyopathy) in cancer survivors many years after cessation of chemotherapy. In addition, predisposition to cardiotoxicity varied considerably among individuals. The long-held notion that DOX cardiotoxicity is caused by reactive oxygen species formed from the redox-cycling of DOX semiquinone lacks rigorous proof in a chronic animal model, and administration of reactive oxygen species detoxifying agents failed to reverse DOX-induced cardiac problems. In this review, I discuss the pros and cons of the reactive oxygen species pathway as a primary or secondary mechanism of DOX cardiotoxicity, the role of topoisomerases, and the potential use of mitochondrial-biogenesis-enhancing compounds in reversing DOX-induced cardiomyopathy. New approaches for well-designed clinical trials that repurpose FDA-approved drugs and naturally occurring polyphenolic compounds prophylactically to prevent or mitigate cardiovascular complications in both pediatric and adult cancer survivors are needed. Essentially, the focus should be on enhancing mitochondrial biogenesis to prevent or mitigate DOX-induced cardiotoxicity.

Advanced Imaging Modalities to Monitor for Cardiotoxicity

Early detection and treatment of cardiotoxicity from cancer therapies is key to preventing a rise in adverse cardiovascular outcomes in cancer patients. Over-diagnosis of cardiotoxicity in this context is however equally hazardous, leading to patients receiving suboptimal cancer treatment, thereby impacting cancer outcomes. Accurate screening therefore depends on the widespread availability of sensitive and reproducible biomarkers of cardiotoxicity, which can clearly discriminate early disease. Blood biomarkers are limited in cardiovascular disease and clinicians generally still use generic screening with ejection fraction, based on historical local expertise and resources. Recently, however, there has been growing recognition that simple measurement of left ventricular ejection fraction using 2D echocardiography may not be optimal for screening: diagnostic accuracy, reproducibility and feasibility are limited. Modern cancer therapies affect many myocardial pathways: inflammatory, fibrotic, metabolic, vascular and myocyte function, meaning that multiple biomarkers may be needed to track myocardial cardiotoxicity. Advanced imaging modalities including cardiovascular magnetic resonance (CMR), computed tomography (CT) and positron emission tomography (PET) add improved sensitivity and insights into the underlying pathophysiology, as well as the ability to screen for other cardiotoxicities including coronary artery, valve and pericardial diseases resulting from cancer treatment. Delivering screening for cardiotoxicity using advanced imaging modalities will however require a significant change in current clinical pathways, with incorporation of machine learning algorithms into imaging analysis fundamental to improving efficiency and precision. In the future, we should aspire to personalized rather than generic screening, based on a patient’s individual risk factors and the pathophysiological mechanisms of the cancer treatment they are receiving. We should aspire that progress in cardiooncology is able to track progress in oncology, and to ensure that the current ‘one size fits all’ approach to screening be obsolete in the very near future.