Practical Cardio-Oncology

Susan F. Dent, Susan F. Dent

• Publisher: CRC Press
• Year: 2019
• ISBN:
  9781351583565
• Edition: 1
• Topic: Médecine
• Subtopic: Théorie, pratique et référence de la médecine

This book takes a holistic view of the treatment of cardio-oncology patients, from evaluating those at high risk of developing cardio-toxicity, guidance for monitoring and managing patients during therapy to cardiac care of cancer survivors. Throughout, this book utilizes the latest research and guidance to offer advice on treatment strategy as well as practical elements of such as training, cardio-oncology nursing, patient education and how to establish a cardio-oncology unit. This book focuses on the practical knowledge and skills key to successful collaboration between cardiologists and oncologists to achieve the optimum cardiac care for cancer patients.

Key Features

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• Focuses on the practical elements of cardio-oncology care

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• Outlines the importance and process of setting up a cardio-oncology unit and cardio-oncology fellowships

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• Provides advice and guidance on the set up and common pit falls of coordinating care for cardio-oncology patients

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• Outlines current guidelines and potential future directions for the field of cardio-oncology

Part I

Introduction

1Cardio-oncology: How a new discipline arrived

Susan F. Dent, Nestor Gahungu, Moira Rushton-Marovac, Josee Ivars, Carlo Cipolla, and Daniel J. Lenihan

1

Cardio-oncology: How a new discipline arrived

Susan F. Dent, Nestor Gahungu, Moira Rushton-MAROVAC, Josee Ivars, Carlo Cipolla, and Daniel J. Lenihan

Introduction

Cancer and heart disease

Cardio-oncology: An emerging multidisciplinary field

Outline of book chapters

References

Introduction

Mortality rates due to cancer have decreased over the last 30 years owing to improvements in early detection strategies, improved surgical approaches, and advances in cancer treatments (1–3). By 2026, it is expected there will be over 20 million cancer survivors in the USA alone (1). Cancer survivors are at risk, not only of cancer recurrence, but of the long-term consequences of their treatment, including cardiotoxicity. Cardiovascular disease is now the second leading cause of morbidity and mortality in cancer survivors (2). Conventional chemotherapy and targeted therapies are associated with cardiac damage, including left ventricular (LV) dysfunction and heart failure, treatment-induced hypertension, thromboembolic events, coronary vasospasm, and arrhythmias. Early and late effects of radiation therapy can lead to coronary artery disease, pericardial disease, valvular heart disease, and arrhythmias. Cardio-oncology has emerged as an essential discipline in medicine, in response to the combined decision-making necessary to optimize the care of cancer patients receiving cardiotoxic cancer therapy. This chapter will focus on the history of cardio-oncology, the present landscape, and briefly discuss future challenges and directions.

Cancer and heart disease

Cancer and cardiovascular disease account for over 45% of deaths in the USA (3). Mortality rates due to cancer alone have decreased over the last 30 years owing to improvements in early detection strategies, improved surgical approaches, and advances in cancer treatments (1,3). Modern treatments have led to an improvement in the chances of surviving a diagnosis of cancer: 5-year survival rate for early breast cancer increased from 70% in 1990 to 88% in 2012 (4,5). Similar improvements have been seen in other solid and hematological malignancies (3). By 2026, it is expected that there will be over 20 million cancer survivors in the USA alone (1). Established and novel treatments such as anthracyclines, HER-2-targeted agents, and immunotherapy, typically used in the treatment of a wide range of cancers, are associated with an increased risk of cardiovascular injury, including cardiomyopathy and heart failure (6).

The incidence of cancer treatment related cardiovascular injury varies widely depending on the specific cancer therapy prescribed, duration of therapy, and underlying patient comorbidities. The population is aging—by 2050 over 20% of the U.S. population will be over 65 years of age (7); a risk factor for the development of both cancer and heart disease. Other common shared risk factors include obesity, tobacco use, and lack of exercise. Given the overlap of risk factors for both cancer and heart disease, patients may have established cardiovascular disease prior to the detection of their cancer (8), placing them at a greater risk of cardiovascular complications. This presents a great challenge to healthcare professionals, especially oncologists, who are tasked with prescribing cancer therapies which may have a detrimental impact on cardiovascular health. Consequently, although current cancer treatments can achieve desirable clinical outcomes, patients with existing cardiovascular (CV) comorbidities and those at significant risk of cancer-related CV complications, may be denied life-preserving cancer therapies due to the overwhelming risk of cardiotoxicity and the unknown extent of its deleterious effects.

The interplay of cancer and heart disease and the respective metabolic pathways is complex. Our knowledge of the CV effects of chemotherapeutic drugs continues to stem from clinical trials in cancer patients that shed light on these shared functional pathways (9).

It is speculated that cardiac dysfunction, in some patients, may result from cancer agents that cause transient myocardial dysfunction like the phenomenon known as myocardial stunning. In 2005, a classification first proposed in an editorial published in the Journal of Clinical Oncology (10) classified cardiac dysfunction into two distinct types, namely Type 1 and Type 2. Type 1 was thought to be due to anthracycline-induced myocardial damage and more likely to be permanent and irreversible, whereas Type 2 was secondary to trastuzumab-induced myocardial dysfunction and had a higher likelihood of recovery. However, based on our current knowledge of the mechanisms of cancer therapy related cardiac dysfunction with different cancer agents, this classification should be considered overly simplistic and irrelevant in clinical practice today. There are now over nine classes of cancer drugs that may, through different mechanisms of action, cause CV dysfunction (e.g., rhythm disturbances, severe hypertension, valvular heart disease, cardiac ischemia) in cancer patients (11). These CV complications depend on the prescribed cancer regimen, duration, and the patient’s preexisting comorbidities.

This advancing level of complexity sparked a need for research in this field and set the stage for the development of the new discipline of cardio-oncology, which aims to improve the overall clinical outcomes of patients with cancers. Oncologists and cardiologists are called together in a partnership to provide collaborative care for cancer patients receiving cardiotoxic therapy. This has resulted in the development of several clinical guidelines with recommendations on screening techniques, the use of biomarkers and cardiac imaging for detecting cardiac injury, as well as risk assessment and stratification of cancer patients. These guidelines have been largely based on data from the adult breast cancer literature, as it pertains to the CV toxicity of anthracyclines and HER-2-targeted agents. Further research is needed to develop evidence-based recommendations in other solid and hematological malignancies.

Cancer treatment and cardiotoxicity: The basis for cardio-oncology

Daunorubicin was the first anthracycline-based cancer therapy to be identified from the soil bacterium Streptomyces peucetius in the 1950s (12). Since this discovery, several other anthracycline drugs have been discovered and found to be effective as chemotherapeutic agents (13,14).

Cardiotoxicity as a concept became recognized in the 1960s when anthracyclines were found to be strongly associated with an increased risk of cardiomyopathy and heart failure in a dose-dependent manner (15,16). In 1979, a retrospective analysis of 4018 patient records found that clinically overt congestive heart failure (CHF) occurred in 2.2% of patients who had received anthracycline-based therapies (16). The cumulative incidence of CHF increased from 3% in patients receiving doxorubicin at a moderate dose (400 mg/m2) to 18% in those being treated with high doses (700 mg/m2) (16). Subsequent studies demonstrated that subclinical LV dysfunction, not measured in earlier studies, was highly prevalent among patients receiving anthracycline chemotherapy (17). As shown by Swain et al. in a large retrospective analysis of data from three phase III prospective trials of breast and lung cancer treatment with doxorubicin, the prevalence of subclinical LV dysfunction or overt clinical CHF can be as high as 54% in patients receiving a cumulative dose of doxorubicin at 500 mg/m2, while up to 48% of patients receiving high doses (cumulative doses of 700 mg/m2) of doxorubicin would be expected to develop clinically overt CHF (18).

Since the first documented complete cure of a human solid tumor by chemotherapy in 1953, significant milestones have been made in cancer treatments, offering cancer patients a better chance of survival. Some recent advances include the discovery of monoclonal antibodies, such as trastu...