Cancer and heart disease are the two leading causes of death. As we live longer lives, we are more likely to eventually have one or the other. But for many cancer patients, treatment of their condition makes it much more likely that they will have to deal with both.
More people are surviving cancer, but they must face the long-term impact of damaged hearts, said oncologist Susan Dent, MD. This is because some of the most widely used chemotherapy drugs are cardiotoxic—they can cause heart problems that include arrhythmias, heart failure, heart attack, hypertension and blood clots.
CCS Position Statement
Dr. Dent, co-founder of the Ottawa Cardiology-Oncology Clinic at The Ottawa Hospital, led the session presenting the Canada Cardiovascular Society’s (CCS) first position statement on cardiovascular complications of cancer therapy (expected release in December 2015).
The position statement optimizes care for patients with cardiovascular disease or who are at risk of cardiotoxicity. Ottawa Heart Institute cardiologists Ellamae Stadnick, MD, an affiliate of the Cardiology-Oncology Clinic, and Haissam Haddad, MD, were among the reviewers.
Cancer and heart disease share major risk factors, such as large waist circumference and low physical activity levels. Having cardiovascular risk factors makes the likelihood of developing heart disease due to cancer therapy more likely.
Some of the most widely used chemotherapy drugs are cardiotoxic.
More drugs are under development for cancer treatment than any other disease area. The CCS statement identifies cardiotoxicity information by cancer drug type. For example, anthracycline-based chemotherapy is associated with heart failure and left ventricular dysfunction. As new cancer drugs are developed, physicians need to be aware of their impact on the heart, said Dr. Dent.
Prevention and Treatment of Cardiotoxicity
The CCS statement recommends that routine cardiovascular evaluation should be part of care before, during and after cancer treatment, and all patients receiving cardiotoxic therapy should be considered to be at high risk for heart failure (stage A). While standard drugs to prevent and manage heart disease can reduce the risk of cardiotoxicity, up to one third of cancer patients may not tolerate these therapies.
Attention should be paid to potential drug interactions and impacts. For example, anticoagulants can be challenging due to the multiple procedures and line insertions that cancer patients undergo.
For patients at risk of cardiotoxicity, good communication between the oncologist, cardiologist and family physician is essential. A multidisciplinary team approach involving cardiology, medical oncology, nursing, social work, rehab and pharmacology improves cardiac outcomes for cancer patients.
The second leading cause of death for breast cancer patients is cardiotoxicity from anthracycline chemotherapy. Finding ways to identify cardiotoxicity earlier can save lives. Kevin Boczar, MD, a resident at the University of Ottawa, has worked closely with the Ottawa Heart Institute’s imaging group to assess the potential of right ventricular (RV) function as an earlier marker of cardiotoxicity. His work won him the Canadian Society of Echocardiography Bursary Award for top abstract by a cardiology fellow or resident.
Currently, the function of the left ventricle (LV) of the heart is the common measure of cardiac damage due to cancer therapy. Dr. Boczar’s study found that anthracycline chemotherapy does impair RV function in breast cancer patients and that further study and assessment is warranted.