As cancer therapy becomes more effective and the number of cancer survivors increases, doctors are faced with a new challenge: ensuring patients have a healthy heart to enjoy the rest of their lives.
The University of Michigan Samuel and Jean Frankel Cardiovascular Center, working with specialists at the U-M Comprehensive Cancer Center, has launched Michigan's first cardio-oncology clinic, a program designed to prevent or minimize heart damage caused by chemotherapy and radiation.
Only a handful of hospitals around the world have dedicated programs of scientists and physicians working to address cancer treatment's impact on the heart.
Preventing heart disease in cancer patients is gaining more importance as aggressive cancer therapies are used on older patients who may already have heart disease, and researchers identify a growing number of cardiovascular side effects of anti-cancer therapy.
"The goal of the collaboration between cardiologists and oncologists is to eliminate cardiovascular complications as a barrier to effective treatment of cancer patients, by providing prevention and early detection of cardiac complications, cardiovascular monitoring during anticancer therapy, and therapy of cardiovascular disease that develops during chemotherapy," says University of Michigan cardiologist Elina Yamada, M.D.
Physicians will use strain imaging with echocardiograms to help detect heart damage in its earliest stages before heart function deteriorates.
Radiation to the chest, especially among patients with left-sided breast cancer, leukemia and chest tumors, can lead to inflammation of the heart's protective sac, the pericardium, or narrowing and stiffening of heart valves.
Current radiation techniques spare the heart much more than earlier treatment approaches, but research is underway at the U-M Comprehensive Cancer Center to further reduce radiation exposure to the heart.
Radiation is one of several issues to consider, but cardiotoxicity - when cancer drugs have toxic effects on the heart - is also a concern.
"The diagnosis of cardiac problems during cancer treatment can be difficult based on symptoms alone, as some of them, such as fatigue, shortness of breath and swelling, can be caused by the adverse effects of chemotherapy. Therefore, when patients present with these symptoms, it is important to have cardiac evaluation," says Yamada.
Heart problems linked to cancer treatment include heart failure, chemotherapy-induced hypertension, arrhythmias, thromboembolism (blood clots) or cardiac ischemia, a sudden severe blockage of a coronary artery that can lead to a heart attack.
Tom Shumaker, 65, of Grosse Pointe, Mich., and his doctors are paying closer attention to his high blood pressure as he undergoes a second round of cancer treatment at the U-M Comprehensive Cancer Center. His physicians noticed a spike in blood pressure following chemotherapy, and now he monitors his blood pressure at home daily.
"There are powerful drugs at work helping me to survive," says Shumaker, an attorney and philanthropist who has survived cancer for 17 1/2 years. "It's not surprising that they would have an impact on other parts of my body. It's something to watch out for, and I do."
About one-third of cancer patients who receive chemotherapy drugs such as trastuzumab (Herceptin) and anthracyclines will develop cardiotoxicity. A small percentage of these patients will have to stop therapy because of side effects.
"Our goal will be early detection and to protect patients with heart medications," says U-M cardiologist Monika Leja, M.D.
Basic scientists in cardiology and oncology will be a part of the cardio-oncology program, working to better understand the mechanisms of cardiotoxicity at the cellular level, and participating in new chemotherapeutic drug studies with the goal of minimizing cardiotoxicity in future cancer drugs.
The doctors say patients can do some things on their own to avoid potential heart trouble during cancer treatment, such as eating a low-cholesterol diet, getting regular exercise, avoiding obesity, and controlling blood pressure and blood sugar.
To make an appointment at the cardio-oncology clinic, call or email the University of Michigan Cardiovascular Center New Patient Coordination Center at 888-287-1082.
Things to know about cancer and the heart
• More than 2 million breast cancer survivors in the United States are believed to be at risk for cardiotoxicity.
• Pediatric cancer survivors have a considerable long-term risk of heart disease. Chances of developing heart disease are 2 to 3 times higher than the general population, especially if they smoke or develop diabetes.
• Cancer treatment and heart care can happen at the same time; oncologists and cardiologists can investigate different cancer therapies that won't worsen heart conditions.