As cancer care evolves and new treatments help more people survive and thrive after a cancer diagnosis, a related medical subspecialty is evolving alongside. Called cardio-oncology, this relatively new field of medicine specializes in the diagnosis and treatment of cardiac problems caused by common cancer drugs.

Since the 1950s, physicians have used a class of drugs called anthracyclines to treat certain cancers, including leukemia, lymphoma, and breast and lung cancer. While these drugs are effective against cancer, some patients whose lives are saved by them also develop high blood pressure, abnormal heart rhythms or heart failure during or soon after treatment. Consequently, scientists have studied these drugs to understand their relationships to heart problems, or their cardiotoxicity.

Because cardiotoxicity has been identified as a potential side-effect of chemotherapy, oncologists increasingly assess their patients’ cardiac health during treatment and refer them to cardiologists to manage the effects of cardiotoxicity. And because an increasing number of people need cardiac care due to cancer treatment, some cardiologists have begun to specialize in treating this patient population. These specialists are the first cardio-oncologists.

The American College of Cardiology recognized the field of cardio-oncology in 2015, and there are currently 1,004 physician members in its Cardio-Oncology Section. The section’s mission is to “improve the cardiovascular health of patients with cancer and cancer survivors through education, training, research development and interdisciplinary collaboration.”

Daniel Lenihan, MD, a cardio-oncologist at the Washington University and Barnes-Jewish Heart & Vascular Center, says, “We help manage cardiac problems that may pre-exist cancer therapy, that may be exacerbated by cancer treatment or that may develop in a survivor of cancer. One of our primary goals is to detect problems as early as possible so we can correct any developing conditions, or better yet, prevent them from occurring.”

A cardio-oncologist joins a patient’s cancer-care team when an oncologist refers the patient for assessment and treatment or when a patient with a history of heart disease or specific cardiac concerns makes an appointment. “We are working more closely with our oncology colleagues to collaborate and communicate about patient care,” Lenihan says.

At Barnes-Jewish Hospital, a patient with cancer will see his or her oncologist and cardio-oncologist during separate appointments, but the physicians share patient records and communicate directly to coordinate care.

“The key is really about communication — and there is no set way in which we support an oncologist or a patient through treatment,” Lenihan says. “We want to help patients develop a comfort level with each provider of care. In some situations, the cardio-oncologist may take the lead in treatment; in others, act as an advisor. The goal is to find the best way to support and improve patient care.”

As the field of cardio-oncology grows, more people will benefit. “We’re going to see more cardio-oncologists joining the field and participating in the management of cancer care — and that’s a win-win,” Lenihan says. “A more robust care team helps oncologists and patients alike. This is just the beginning of an important new field.”