​Chemotherapy, like anthracyclines (a class of drugs) which are used in treating haematological cancers such as lymphomas, can sometimes weaken the heart pumping function over time. This usually occurs at higher cumulative doses. Breast cancer patients on therapies targeting HER2 (a type of protein) may also experience a transient drop in heart function.

In mild cases of reduced heart pumping function, patients may not experience any symptoms. In more severe cases, patients may develop heart failure symptoms such as severe shortness of breath on exertion, and on lying down, legs swelling or lethargy. Sometimes, these symptoms can be nonspecific and may overlap with cancer-related symptoms, making diagnosis challenging. Hence, the presence of heart failure is best assessed with laboratory blood test and biomarkers and confirmed with imaging modalities such as echocardiography or cardiac MRI.

Radiation therapy of chest tumours (like those in the mediastinal or left breast) may sometimes affect the heart because of their proximity. In some patients, this can accelerate atherosclerosis (thickening) of the heart vessels, resulting in heart attacks years after radiotherapy. Moreover, some chemotherapy agents may cause vasospasm (narrowing) of the heart vessels, causing chest pain.

Patients with myocardial ischaemia often presents with chest discomfort, which is typically described as heaviness in the chest that is worse with exertion and better with rest. This can sometimes be accompanied by cold sweats or breathlessness.

Certain cancer therapies that help the immune system, such as the immune checkpoint inhibitors, can sometimes lead to over-activation of one’s immune system and cause inflammation of the heart muscles, but this is rare.

It is crucial to assess the risk for cardiovascular complications before starting cancer treatment. Patients with pre-existing cardiovascular risk factors or a history of cardiotoxicity should undergo comprehensive cardiac evaluation, including echocardiography and biomarker tests. For prostate cancer patients on hormone therapies, it is important to manage their cardiac risk factors such as high cholesterol, and diabetes4.

Several cardioprotective strategies can lower the risk of cardiac complications before and during cancer treatment. These strategies may involve the use of cardioprotective agents like statins with anthracyclines

before starting chemotherapy for lymphomas, the use of medications such as ACE-inhibitors and beta blockers, or regularly monitoring heart function with serial echocardiography.

In some cases, adjusting the cancer treatment plan or using alternative therapies with fewer cardiotoxicity side effects may be necessary to balance the cancer control and the protection of the heart.