Cancer and the heart
The fight against cancer has grown stronger over the years. Early disease diagnosis and treatment have significantly improved. Cancer patients now have longer survival. However, as newer anticancer therapies are developed, the number of cancer survivors with cardiovascular complications escalates. It is a challenge to the clinician to find a balance in treating cancer without compromising the efficacy of anticancer therapy when concomitant cardiovascular morbidities are present or there is a risk of acquiring cardiac side effects. This developing concern of potential cardiovascular morbidity and mortality brought about by cancer and its treatment has been noted globally. In line with this trend, several healthcare institutions abroad have established multidisciplinary programs dedicated specifically for the care of these patients.
Cardio-oncology is a cardiovascular subspecialty with a multidisciplinary integrative approach for the management of cancer patients. This clinical practice includes cardiologists, oncologists, hematologists, radiooncologists, nurses and pharmacists dedicated in promoting preventive and proactive strategies. Integral to the practice are identification of patients at risk and prevention of side effects. The goal is to monitor and treat cancer patients with cardiovascular disease or who are at risk in acquiring complications caused by the malignancy or due to the anticancer therapy.
Cancer by itself, in general, may cause condition of a hypercoagulable state or a predisposition to cause blood clotting. Potential side effects caused by anticancer treatment, whether chemotherapy or radiation therapy include complications caused by injury to the coronary and peripheral vasculature. One of the adverse cardiovascular effects that should be recognized early on is cardiac dysfunction which could devastatingly lead to congestive heart failure. Some chemotherapy agents such as anthracyclines (doxorubicin) and monoclonal antibody-based tyrosine kinase inhibitors (trastuzumab) which are commonly used for treating breast cancer are associated with heart failure and left ventricular dysfunction due to its direct toxic effects to the heart. The cardiac complication related to these agents carries one of the worst prognoses. Heart attacks, stroke, pulmonary embolism, electrical abnormalities of the heart, and limb ischemia are cardiac emergencies known to be associated with particular chemotherapy agents. Commonly used chemotherapy offenders associated with heart attacks are antimetabolites, namely fluorouracil and its oral pro-drug capecitibine. Other drugs, such as antimicrotubule agents (paclitaxel) can cause vasospasm. Alkylating agents (cisplatin) are associated with coronary thrombosis and venous thromboembolism. Management of cancer patients with acute coronary syndromes also needs special considerations that require an interdisciplinary approach.
Radiation therapy can cause cardiovascular side effects. Not only cancerous cells are destroyed, but non-cancerous cells hit by the field of radiation may be affected as well. The endothelial cells that line the interior surface of blood and lymphatic vessels are the most susceptible. Coronary and peripheral arterial disease induced by radiation therapy remains a concern for patients being treated for a variety of malignancies. An example is an increased risk of stroke and carotid artery disease for patients treated with radiation therapy for head and neck cancer.
Lymphedema is one of the side effects of cancer. This refers generally to swelling of the upper or lower extremities due to fluid build up after removal or damage to the lymph nodes, which commonly happens after surgery, radiation therapy or from blockage to the lymphatic system in cancer patients. Recommended treatment, such as elastic bandages, compression stockings, manual lymphatic drainage (MLD) and exercise, is also addressed by the cardio-oncology service, through combined efforts of vascular specialists and a certified lymphedema nurse therapist.
Cardio-oncology programs aim to raise awareness in dealing with these complicated issues. The rationale in providing this service is to ensure better outcomes for cancer patients with or without existing cardiovascular problems or who are at risk of acquiring cardiac disease, without compromising cancer treatment. Preventing and reducing further cardiac damage by guiding oncologists and other specialists in detecting early signs of complications are of paramount importance. This service is to assist patients in a continuous, interdisciplinary and comprehensive approach from initial assessment to long-term follow-up.
St. Luke’s Medical Center-Global City now offers cardio-oncology services at the Heart Institute which focus on early detection, cardioprotection and intervention for such patients. The service includes thorough screening and risk assessment monitoring by a team of specialists from the Heart and Cancer Institutes. Advanced cardiac imaging, vascular and lymphedema clinic with a certified therapist, cardiac arrhythmia and invasive cardiology assessment are some of the services offered. Assisting cancer patients in a high-level standard of care is the goal.
St. Luke’s Cardio-oncology services aim to guide patients in dealing with cardiac issues in a collaborative, proactive team-based approach. As a team, the goal is to provide the best possible care for the heart of a cancer patient. As a team, the aim is to work towards preventing potential heart complications of a patient. As a team, the drive is to keep the heart stronger to give every cancer patient the ability to live a fuller and longer life.
Dr. MARIA KATRINA C. TAN is a cardiologist and active consultant for Echocardiography at St. Luke’s-Global City where she is also a member of the Training Committee for fellowship in Cardiology and Coordinator of the Cardio-Oncology Clinic. She is also a Coordinator of the Acute Coronary Syndrome (ACS) Registry (St. Luke’s-Global City chapter) for the Philippine Heart Association. For inquiries, call the St. Luke’s-Global City Heart Institute at (632) 7897700 ext. 2000/2010.