Imaging crucial to cardio-oncology strategy
Imaging is an important component of preventing HF in patients with cancer, especially in patients treated with therapies known to cause left ventricular dysfunction, the president of the American College of Cardiology said at the American Society of Nuclear Cardiology Annual Meeting.
“Subclinical LV dysfunction is present in many cancer survivors,” said Mary Norine Walsh, MD, FACC, medical director of the HF and cardiac transplantation programs at St. Vincent Heart Center in Indianapolis and a Cardiology Today Editorial Board Member. “This is a group of patients who are often lost to follow-up. Thankfully, with cardio-oncology programs, many more of these patients will be followed by cardiologists and not just oncologists.”
Imaging strategies figure prominently in the American Society of Clinical Oncology cardio-oncology guidelines, Walsh said.
“I would encourage you to read this paper,” she said. “The standards for prevention and monitoring include strategies prior to the therapy, and monitoring during and after treatment.” For example, she said, one recommendation calls for patients to receive an echocardiogram 6 to 12 months after completion of therapy, and another states cardiac MRI is reasonable in certain asymptomatic patients after treatment for cancer.
Patients who are undergoing cancer treatment and those who have survived it can range from stage A to stage D HF, and those who have been treated with anthracyclines or HER2 therapeutics need to have their LV ejection fraction assessed, Walsh said.
“For a number of years, we had our oncologists ordering imaging somewhat randomly,” she said. “In the past, all we did was check the baseline EF and reduce the anthracycline dose if needed. We didn’t have any early understanding of what was going on in the ventricles of patients with cancer.
“Now, we think differently,” Walsh said. “For anthracyclines, we look at doing imaging with echo or [cardiac magnetic resonance], depending on your institution, both pretreatment and after a cumulative dose of more than 300 mg/m2.”
Also of note, she said, is a paper published in the Journal of the American College of Cardiology in 2014 by Paaladinesh Thavendiranathan, MD, from the division of cardiology, Peter Munk Cardiac Center, Toronto General Hospital, University Health Network, University of Toronto, and colleagues on using myocardial strain imaging by echocardiography to detect early signs of cardiotoxicity after cancer treatment.
According to Walsh, the paper offers “injury detection algorithms we can use, which will guide our therapies with ACE inhibitors, beta-blockers and aldosterone inhibitors.”
The field has gone beyond merely measuring LVEF, according to Walsh.
“Normal LVEF at baseline doesn’t predict anything, and a drop in LVEF is a very late event,” she said. “LV strain in patients with cancer has changed the field of cardio-oncology because we can understand what’s going on in a patient’s heart prior to a decline in LV function. We can perform pretreatment risk stratification, identify dysfunction early, predict recovery and conduct surveillance and treatment of subclinical LV dysfunction. What we’re after with strain imaging is identifying patients early and then engaging the patient and the oncologist in a discussion of where we go from there. What is the patient’s most proximate risk of death? Is it the cancer or the early cardiomyopathy?” – by Erik Swain
Walsh MN. Multimodality imaging in the diagnosis and management of heart failure. Presented at: American Society of Nuclear Cardiology; Sept. 14-17, 2017; Kansas City, Mo.
Disclosure: Walsh reports no relevant financial disclosures.