Despite the known toxic effects of chemotherapy on the heart, the majority of women undergoing breast cancer treatment are not getting the recommended follow-up heart scans, according to research presented at the British Cardiovascular Society (BCS) Conference in Manchester today. The research was carried out at the University of Dundee and funded by the Grant Simpson Trust and the Tayside Oncology Research Endowment Fund.
Developments in chemotherapy mean 87 per cent of people survive breast cancer for five years or more. Unfortunately many of these people later suffer adverse effects on the heart caused by the treatment. Because of this current breast cancer treatment guidelines recommend the patient's heart function is assessed before, during and after chemotherapy.
The researchers analysed medical records from the CHEMOCARE database focusing on the 1229 breast cancer patients who were treated with either anthracyclines alone or combined with the monoclonal antibody trastuzumab at Ninewells Hospital, Dundee between January 2003 and December 2014.
Despite clear guidelines that women receiving these treatments should have their heart function monitored, only 625 (51 per cent) of the women underwent an echocardiogram to check that their heart function was normal before starting chemotherapy. Of these, only 238 (38 per cent of those screened) had follow-up scans during the course of their treatment, as recommended by the guidelines. Although the researchers expect their findings to be representative of cancer treatment across Scotland and the wider UK, a broader analysis is needed to confirm this.
Chemotherapy can weaken the heart making it less able to pump blood around the body properly. This can ultimately lead to heart failure, which is a serious chronic condition that can be debilitating and, ultimately, fatal. Over half a million people in the UK are living with heart failure but the majority of these cases are caused by damage to the heart after a heart attack. More research is needed to determine just how common heart failure is following chemotherapy and to determine why it happens.
Dr Jagdeep Singh, Clinical Research Fellow and Honorary Cardiology Registrar at the University of Dundee and Ninewells Hospital, said:
"We've been seeing an increasing number of patients in the heart failure clinic following chemotherapy. This triggered our interest in finding out why and we wanted to see the scale of this problem. We were able to start doing this and evaluate treatment practices by accessing and analysing anonymous medical records.
"Improvements in chemotherapy mean we've been able to transform breast cancer from an often fatal condition into a very treatable disease. But, due to the real risk of heart failure, our findings show that doctors need to be more vigilant and institute protective heart treatments earlier."
Professor Peter Weissberg, Medical Director at the British Heart Foundation (BHF), said:
"Thanks to research, more women are surviving breast cancer than ever before but it is very worrying that some of them go on to develop life threatening heart disease as a consequence of their chemotherapy. This research suggests that oncologists and cardiologists should work together from the outset to minimise the detrimental effects of chemo on the heart, while ensuring the best chance of survival from the cancer.
"Cardio-oncology is a new specialty which has only come about because of improved cancer survival and we hope to see greater cooperation between heart doctors and cancer doctors in the future. The BHF is currently funding research into how some chemotherapy drugs cause the heart muscle to weaken, in the hope that future breast cancer patients' hearts can be protected.
"If you're undergoing cancer treatment and are concerned about its effects on your heart, please visit the BHF website to find an information booklet that the BHF produced with Macmillan Cancer Support on this topic."
Elizabeth Kidd, aged 69 from Brechin in Scotland, underwent chemotherapy for breast cancer around Christmas in 2000. At the time she was warned that the treatment could cause some heart problems but it was not until 2005 when she first started getting symptoms.
In 2008 Elizabeth was diagnosed with atrial fibrillation and heart failure, which means she now has to take up to 8 different medications a day for those conditions alone. Although her heart failure is being managed well, her condition can leave her too breathless to walk uphill to her local shop.
Elizabeth said: "I didn't think about my heart and that something could go wrong with it. At first I thought my breathlessness was down to my fitness so it was a real shock to learn I had heart problems.
"When I was diagnosed with breast cancer the odds of beating it weren't as good as they are now so I'm grateful that the treatment I received has helped me beat it. I try to stay positive about my heart problems. My hope is that more research into this will mean women like me who beat breast cancer won't go on to develop heart failure."
British Heart Foundation (BHF)