New advice aims to reduce the cardiac side effects of cancer treatment

The first European Society of Cardiology (ESC) Guideline on cardio-oncology is published online today in European Heart Journal. The advice aims to reduce the cardiac side effects of cancer treatment so that patients can safely receive their therapy.

Cancer treatments including chemotherapy, radiation, targeted therapy and immunotherapy have the potential to cause cardiovascular disease. Due to cancer therapy’s success in prolonging survival, growing numbers of people now live with heart disease as a result of their treatment. Survivors of several solid cancers and lymphoma have a two-fold risk of fatal heart disease compared to their peers.

This document is for health professionals looking after cancer patients and survivors. It provides specific recommendations on management before, during and after administering cancer therapies which have the potential to cause problems with the heart or blood vessels.”

Dr. Alexander Lyon of the Royal Brompton Hospital, London, UK

The first important issue is for oncologists and haematologists to know which therapies could cause heart problems. The second issue is that specific cancer treatments do not create the same level of risk in all patients. Therefore, a baseline cardiovascular assessment is advised to identify patients at high risk; they should be referred to a cardiologist for further cardiac evaluation and optimisation of heart health and risk factors before starting therapy. “This pre-assessment by the cardiologist must be performed urgently to minimise delays to starting cancer treatment,” said guidelines task force chairperson Dr. Teresa Lopez-Fernandez of La Paz University Hospital, Madrid, Spain.

The frequency of cardiac monitoring, known as surveillance, during a treatment with potential to cause heart disease, and the option for starting heart medication upfront to act as protection during cancer treatment, can be tailored to each cancer patient based upon baseline risk, the nature and total duration and dose of cancer therapy, and any pre-existing heart disease.

Preservation and monitoring of heart health during cancer treatment is a key part of the guideline. Patients should be educated on the potential risks and how to reduce them such as quit smoking, exercise at least 150 minutes per week but not to exhaustion, eat a healthy diet, and limit alcohol to 100 grams weekly. Possible cardiac symptoms such as chest pain, breathlessness, fainting, blackouts or fast heart beats (palpitations) should be reported to the cancer team. Tight control of high blood pressure, diabetes and high cholesterol is recommended. Some patients are advised to monitor their blood pressure at home when starting a cancer therapy known to raise blood pressure.

Recommendations are provided for the diagnosis and management of cardiovascular side effects during cancer treatment. One common complication is a weakening of the heart muscle, known as left ventricular dysfunction, which can progress to more severe weakening called heart failure. A typical cause is anthracycline chemotherapies, such as doxorubicin, daunorubicin or epirubicin, which are used for breast cancer, acute leukaemia, lymphoma and sarcoma. If cardiac dysfunction is detected during surveillance with ultrasound scans of the heart called echocardiograms and/or with blood tests for heart injury or strain, then cardiology and oncology teams are strongly recommended to discuss the pros and cons of continuing versus stopping cancer treatment.

Dr. Lyon said: “Multiple factors influence the decision to continue or stop therapy including the magnitude and severity of the heart problem, how early or late in the cancer management plan the problem has developed and how many more treatment doses are proposed, the response of the cancer to the treatment, the options for cardioprotection and their predicted benefit, the range of alternative non-cardiotoxic cancer treatments available, and the patient’s preference and concerns.”

Monitoring in the first year after treatment is recommended in certain groups. These include those who developed a cardiac complication during treatment to assess whether the problem resolves or persists after the cancer drug has cleared from the body. For some patients this will lead to a trial of weaning off cardiac medications started during cancer treatment while others will be recommended lifelong cardiac treatment. Another goal is to detect new heart problems since for some cancer therapies, for example anthracyclines, the majority of cardiovascular side effects are detected in the first 12 months after completing treatment. Patients should continue healthy lifestyle habits, report potential cardiac symptoms, and keep blood pressure, diabetes and high cholesterol under control.

Some patients require long-term surveillance for cardiovascular problems. These include survivors of paediatric and young adult cancers treated with high doses of anthracycline chemotherapy and/or high doses of radiotherapy to the chest, adult cancer patients who developed moderate or severe complications during treatment, survivors of leukaemia, myeloma or lymphoma who required a bone marrow transplantation, and patients on long-term cancer treatments with the potential to cause heart problems after years of treatment. Dr. Lopez-Fernandez said: “Long-term monitoring aims to detect and manage cardiac problems early to prevent severe complications in cancer survivors and avoid cardiovascular side effects in patients on long-term treatments.”

The guideline was developed in collaboration with the European Hematology Association (EHA), the European Society for Therapeutic Radiology and Oncology (ESTRO) and the International Cardio-Oncology Society (IC-OS).