4 December 2015
The findings of new research carried out by experts at Royal Brompton Hospital suggest a possible link between cancer and a decline in heart function.
Whilst it is widely accepted that some common cancer treatments, particularly chemotherapy and drugs such as trastuzumab, are potentially toxic to the heart, the results of this new study – presented at EuroEcho-Imaging 2015 in Seville – raise the possibility that cancer itself may be responsible for causing damage to the heart, regardless of exposure to any cancer treatment.
This could mean that some cancer patients need closer monitoring and may require earlier cardiac interventions to reduce the risk of damage to their heart before, during and after their treatment for cancer.
Cardiologists usually assess how well the heart is working by measuring ejection fraction (EF) through an echocardiogram. This is the percentage of blood pumped out of the left ventricle (the main chamber of the heart) when the heart contracts. While a reduced EF indicates a problem with heart function, it does not always detect very early changes in how well the heart is working.
In this new study, experts from the NIHR Royal Brompton Cardiovascular Biomedical Research Unit used echocardiography to consider a relatively new, more subtle measurement of heart muscle function, known as strain. A reduction in strain is often an early indication that the heart muscle fibres are not contracting well and may occur before any notable change in EF. Strain has previously been shown to be an early predictor of future decline in heart function for cancer patients receiving certain chemotherapy agents.
In the new study, researchers compared strain in 79 cancer patients from the specialist cardio-oncology clinic at Royal Brompton Hospital. All were known to have a normal EF (55 per cent or more) and no pre-existing heart condition. A further 20 healthy individuals were matched to the cancer group for age and gender.
The findings showed that overall the cancer patients had reduced strain measurements compared with the healthy controls. The study then went a step further, looking at the strain of patients who had been exposed to cancer drug therapies (43) and patients with as yet untreated cancer (36). There was no significant difference between strain in both groups of cancer patients.
Dr Rajdeep Khattar, consultant cardiologist at Royal Brompton Hospital and one of the lead researchers in this study, said:
“Our findings raise the possibility that cancer itself – and not just the drugs used to treat it – may have an adverse impact on heart function. Although a relatively small-scale study, the results show that more research is now needed to further investigate this link. If proven, it could change the way cancer patients are cared for in the future with regards to protecting their heart health.
“At the moment, cancer patients don’t routinely have a cardiovascular risk assessment from a cardiologist. Our findings could demonstrate a need for that to change because those with reduced strain may benefit from closer monitoring of their heart function. There may be a greater need for cardio-oncology clinics, like the one at Royal Brompton Hospital, so that any early signs of damage to the heart can be identified.
“It is important to stress, however, that larger and more detailed studies are now required. Whilst we have posed a question about whether cancer itself is damaging to the heart, this is not yet a proven underlying link.”
Patients concerned about how their cancer diagnosis and treatment might impact on their cardiovascular health should speak to their oncologist for advice. Information is also available from Macmillan Cancer Support.
For further information, please contact:
Media relations officer
Royal Brompton & Harefield NHS Foundation Trust
Tel: 020 7352 8121 ext 2237
Mobile: 07891 310924
Follow us on Twitter: @RBandH