How to Build a Cardio-Oncology Service?

This article refers to ‘Activity and outcomes of a cardio-oncology service in the United Kingdom — a five-year experience’ by N. Pareek et al., published in this issue on pages xxx. Cardio-oncology has arisen as one of the most rapidly expanding fields of cardiovascular medicine, both in the research and the clinical setting. There is an exponentially increasing number of research projects and publications, while dedicated cardio-oncology clinics keep appear every day throughout Europe and US. As a result, our understanding of the interaction between cancer and its therapy on one hand and the cardiovascular system on the other is continuously growing.1 The accumulated evidence on the possibilities of risk stratification and early diagnosis of cardiotoxicity provided by sensitive biomarkers and imaging techniques as well as on the benefits of preventive and therapeutic interventions is also increasing. Thus, the organization of cardio-oncology care provision in a structured, integrated and comprehensive service arises as a key requirement.2 In this issue of the Journal, Pareek and colleagues report their 5-year experience of a cardio-oncology programme at the Royal Brompton Hospital, London, UK. They prospectively studied the outcomes of 535 patients with a broad spectrum of cancer types, who attended the programme between 2011 and 2016.3 The authors were able to show that timely cardiovascular evaluation and intervention and close monitoring in the context of a structured service allowed all patients with subtle cardiac abnormalities (biomarker elevation or myocardial deformation impairment), as well as 88% of those with overt cardiotoxicity (left ventricular ejection fraction decline) to continue cancer therapy. In other words, a well-structured cardio-oncology service was able to accomplish the very essence of cardio-oncology, to optimize patients' cardiovascular status in order to ensure that they receive the best available cancer treatment with minimal interruptions because of cardiovascular complications. There are several steps in order to build an efficient cardio-oncology service (Figure 1). The first step is the engagement of the appropriate healthcare professionals. Although a cardio-oncology specialist would be ideal to lead the service, a general cardiologist with an interest in cardio-oncology or a heart failure specialist are also suitable. A nurse and administrative personnel are further necessary, while cardiologists in training and fellows could further populate the team.2 With the exception of dedicated cancer hospitals, the cardio-oncology service would be a part-time occupation for all the aforementioned healthcare professionals, started, for example, as a half-day clinic once or twice weekly and adjusted subsequently to developing requirements. The next step is the definition of the type of services that the programme will provide. Typically, a cardio-oncology service is expected to evaluate patients before cancer therapy, monitor them regularly during and after cancer therapy, if deemed necessary by initial evaluation, and intervene when cardiotoxicity occurs. Additionally, and according to local needs, the service could include pre-operation assessment, although this is usually provided by general cardiology service, as well as evaluation of patients with cardiac tumours.3 A key requirement for the efficient function of the programme is the definition of criteria for the referral of patients to the programme. This is obviously related to the array of provided services, but it generally includes three groups of patients, those at high risk to develop cardiotoxicity because of cancer therapy, those with a history of cardiotoxicity, and those who develop new cardiovascular complications while on cancer treatment. The risk of cardiotoxicity depends crucially on patient profile and history as well as on prior cancer therapy.3, 4 Risk estimation differs according to the type of cancer therapy that the patient is scheduled to receive. For example, a patient scheduled for treatment with a QT prolonging tyrosine kinase inhibitor is at risk if he/she has a baseline QT prolongation or receives other QT prolonging agents. Another example is that women are known to be more susceptible than men to anthracycline-induced cardiotoxicity than to other agent toxicities.4 In general, high-risk individuals are children and elderly and those with a history of cardiotoxicity, established cardiovascular disease, two or more cardiovascular risk factors, or previously exposed to cardiotoxic cancer therapy4, 5 (Figure 2). Probably the most crucial step while designing a cardio-oncology programme is the delineation of monitoring and intervention strategies, both of which are difficult to define, as evidence from the literature is rather controversial and in many cases inconclusive. History taking, physical examination and resting electrocardiography constitute the basic assessment at baseline, followed by resting echocardiography in cases with abnormal findings.4 Additional modalities, such as stress testing or Holter monitoring may be required in selected cases. Patients classified as high risk require further monitoring during treatment. A typical approach, at least for high-risk patients receiving anthracycline-based regimens, would be to perform resting echocardiography every 3 months in the course of chemotherapy and up to a year, followed by biannual assessments for the subsequent 4 years and annually thereafter.6 In addition, a number of studies have provided the grounds for the use of sensitive biomarkers and imaging modalities, including cardiac troponins and myocardial deformation imaging as a means to identify subtle cardiac dysfunction, thus allowing for an early preventive intervention.7-9 However, the heterogeneity of modalities and protocols evaluated by different studies and the hitherto lack of strong evidence on the benefits of primary interventions render the integration of these sensitive markers into clinical practice difficult.10, 11 In contrast, it is clear that baseline optimization of the cardiovascular system with diagnosis and management of any heart disease and control of cardiovascular risk factors is required for all patients undergoing cancer therapy.4 Regarding secondary prevention, there is compelling evidence that anthracycline-induced decline in left ventricular ejection fraction can be effectively managed by angiotensin-converting enzyme inhibitors and beta-blockers, with a response rate of nearly 80%.6 The 2016 European Society of Cardiology position paper on the cardiovascular complications of cancer therapy describes specific management strategies for different forms of cardiotoxicity and suggests a surveillance plan for cancer survivals at risk for long-term complications.4 Finally, establishing the necessary collaborations and network on one hand with medical and radiation oncologists and haematologist who actually treat cancer patients and on the other with additional physicians and healthcare professionals who may be required for the management of patients, is also important for the efficiency of the service (Figure 1). Finally, according to local settings, part of the cardio-oncology team could visit cancer institutes on a regular basis and instead of only receiving patient referrals. As knowledge in the challenging field of cardio-oncology is growing, the continuous integration of advances into everyday clinical practice in a structured manner will ensure the optimization of the cardiovascular care provided to patients with malignancies. Conflict of interest: none declared.