Cardio-oncology is a medical specialty dedicated to caring for the cardiovascular system during cancer treatment, minimizing the risk of heart problems related to cancer or its treatment type.
Due to the increasing incidence of cancer and the longer survival of patients, the prevention and treatment of cardiovascular diseases in this population have gained prominence. Cardiotoxicity is one of the most significant complications of cancer treatment, responsible for considerable morbidity and mortality, increasing not only the risk of death but also of important sequelae for the patient.
Currently, early identification of cardiovascular risk, implementation of risk reduction strategies, correct diagnosis of cardiovascular problems, and institution of effective therapy are essential for the proper care of cancer patients. This set of measures aims to reduce the risk of mortality and improve the quality of life of the patient, without interfering, if possible, with the specific cancer treatment.
What is cardiotoxicity and its main symptoms
Cardiotoxicity is the damage caused to the heart by cancer treatment, which can occur due to an alteration or damage to the heart muscle or the heart’s electrical system, for example. The most concerning injury is heart failure, which occurs when the organ becomes weaker and less efficient in pumping, compromising blood circulation. Other effects of cancer treatment that can affect the patient include acute coronary insufficiency (heart attack), high blood pressure, arrhythmias, and thromboembolic events.
If the treatment regimen causes thrombosis, which can be in the leg or even pulmonary embolism, the symptoms include:
- Rapid breathing, shortness of breath, chest pain, and palpitations, in pulmonary embolism
- Swelling in one leg and redness, increased local temperature, and pain when touched, in the leg
Symptoms of heart failure, which occurs when the heart loses strength, include:
- Symmetrical swelling in the legs
- Shortness of breath during activities that were previously performed normally
- Shortness of breath when lying down, which improves when sitting
- Easy fatigue
Treatments that can cause cardiotoxicity
- Chemotherapy – is not the only treatment that can lead to heart problems, although it is the most common among the therapeutic approaches adopted in oncology. Cardiovascular toxicity varies and depends on the therapeutic regimen used. Certain chemotherapy strategies are directly toxic to the heart, causing it to weaken and leading to heart failure. Other protocols may lead to increased blood pressure or a higher incidence of thrombosis or alteration in coronary circulation – which can cause a heart attack or myocardial ischemia, or cause palpitations and arrhythmias.
- Radiation therapy – when performed in the chest area, can cause involvement of the pericardium, which is a membrane that surrounds the heart. In this way, it can become thicker and harder. In addition, it increases the risk of atherosclerosis (fat plaque in the vessels) in the long term. It can lead to a heart attack.
- Immunotherapy – drugs that stimulate the body’s defense system to fight cancer – can lead to myocarditis, an acute inflammation of the heart, and it is possible that monoclonal antibodies cause heart damage.
The importance of early risk assessment
To prevent heart problems, it is ideal for cancer patients to undergo a comprehensive cardiological evaluation before starting chemotherapy or radiotherapy. In this assessment, in addition to clinical examinations, the doctor may request specific blood tests to evaluate cardiovascular health markers such as Troponins and BNP (Brain Natriuretic Peptide). Additionally, they may also request imaging tests, such as an echocardiogram, for a structural evaluation of the heart.
Electrocardiogram (ECG) – Routinely performed in the evaluation of patients with risk factors for cardiotoxicity. The detection of ventricular and supraventricular arrhythmias, such as atrial fibrillation, alerts the clinician to the presence of cardiac structural damage.
Cardio-specific biomarkers – It is a useful tool in the early identification of cardiac injury from chemotherapy. Blood tests can detect these cardiac-specific biomarkers, suggesting potential development of a heart problem.
Imaging methods – Before starting cardiotoxic chemotherapy, evaluation and quantification of ventricular function by imaging methods are necessary. This measurement should be done through echocardiography. The doctor can discuss with the patient the possible chemotherapy regimens with lower cardiovascular risk. Echocardiography has been the most commonly used option due to its low cost, easy access, and non-invasive nature.
Maintaining a healthy routine aids in prevention
It is important that even after a cancer diagnosis, the patient maintains a routine of physical activity and healthy eating whenever possible. The benefits of these practices are well established in improving quality of life and significantly reducing the risk of developing cardiovascular and metabolic diseases. A sedentary lifestyle is associated with a significant increase in the risk of obesity, metabolic syndrome, and coronary events.
Current evidence suggests that increasing physical activity after a cancer diagnosis may reduce the risk of recurrence and mortality. Cancer and its treatment are associated with a range of systemic metabolic changes that can significantly compromise the quality of life and life expectancy of the patient even after cure, which is why attention to oncological cardiology is so important.
Which doctors should provide guidance on cardio-oncology
Guidance on the risks of chemotherapy agents causing heart problems should initially be provided to the patient by their oncologist. The evaluation and, if necessary, the initiation of schemes to prevent heart problems potentiated by treatment should be done by a cardio-oncologist.
Today, there are specific residencies in cardio-oncology, which are cardiologists by training but specialists in oncology patients. Large centers specialized in oncology treatment have these professionals on the team that follows the patient.
