Cardio-oncology is a rapidly emerging interdisciplinary field of medicine that addresses the concurrent treatment of cancer and cardiovascular disease, and the cardiovascular risks of cancer care. Radiation oncology nurses should be familiar with the conceptual underpinnings of this expanding discipline, the treatment of cardiovascular disease during cancer care, and the ways in which radiotherapy can impact patients’ cardiovascular health.
Cancer treatments, including thoracic radiotherapy, can cause acute and late adverse cardiovascular events; up to one-third of women undergoing adjuvant breast cancer therapy will experience treatment-related cardiotoxicity.1 Cardiovascular tissues, including the myocardium, pericardium, heart valves, and coronary arteries, are radiosensitive and are damaged to varying degrees when exposed to ionizing radiation.2 Patients undergoing high-dose radiation fractions (total radiation doses of 35 to 40 Gy or higher) and who are also receiving chemotherapy (anthracycline or monoclonal antibody therapies such as trastuzumab) are at particular risk of developing cardiotoxicities.2 Among patients with Hodgkin lymphoma or breast cancer, radiation therapy is associated with late cardiovascular disease, including coronary artery disease, valvular dysfunction, pericarditis, and cardiomyopathy.3
As baby boomers age into the highest-risk ages for cancer and cardiovascular disease, cancer care teams are increasingly caring for cancer patients with existing cardiovascular conditions that must be considered, accommodated, and monitored throughout cancer care — and must also educate patients about the cardiovascular risks of cancer treatments, and include cardiovascular health in cancer survivorship plans.3,4 There is, therefore, an urgent need to carefully coordinate clinical cancer care with cardiology — an emerging field at the crossroads of oncology, cardiology, and nursing known as cardio-oncology.2,5,6
COMBINING 2 DISCIPLINES
Oncology nurses will be on the front lines of this discipline, coordinating and implementing the concurrent management of cancer and cardiovascular disease, monitoring and managing treatment-emergent cardiovascular complications, and helping cancer survivors understand and plan against their long-term cancer treatment-related cardiovascular risks. Oncology nurses should therefore be familiar with the signs and symptoms of heart failure, cardiologic diagnostic tests, and surveillance practices.
As multimodality cancer treatment options become more complex and personalized, cardio-oncology clinicians will have to educate patients about the challenges of concurrent heart and cancer care, and will have to devise carefully planned interdisciplinary care plans that seek to avoid, monitor, detect, and manage a growing array of potential oncologic and cardiovascular interactions and complications.7-10 Professional oncology and cardiology organizations recognize the pressing need for coordinated cardio-oncology care and have begun to promulgate clinical practice guidelines.11-13 The American Society of Clinical Oncology (ASCO) has recommended, for example, that providers initiate cardiac dysfunction risks with at-risk patients prior to therapy to make sure that cancer care planning addresses patient priorities and values, and that high-risk cancer survivor populations (such as those undergoing thoracic [chest or mediastinum] radiotherapy in which the heart and major blood vessels fall within irradiated volumes, or cardiotoxic anthracycline cancer chemotherapy) be educated about treatment options and cardiotoxicity prevention and screening strategies.6,11 Alkylating agents and antiestrogen therapy are also associated with heart complications.5
“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,” the ASCO clinical practice guideline states.11 “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.”
In 2016, the Society for Cardiovascular Angiography and Interventions (SCAI) published consensus recommendations for cardiology, oncology, and internal medicine clinicians about caring for patients with cardiovascular disease and cancer, noting that the evidence base is immature because cancer patients’ data is not included in percutaneous coronary interventions registries and cancer patients are typically excluded from randomized clinical cardiology trials.13 The recommendations detailed cardiovascular screening, cardio-protection, and invasive cardiovascular evaluations and therapeutic coronary interventions for patients with anemia and thrombocytopenia.13 The authors also recommended deferred cardiovascular stenting for heart disease during cancer treatment, when possible.13