Cancer patients undergoing radiation therapy need to have baseline studies of cardiac function and routine screening for heart disease, according to recommendations from the European Society of Cardiology and the American Society of Echocardiography published July 16 in the European Heart Journal–Cardiovascular Imaging.
The groups recommend baseline preradiation echocardiography along with a cardiac exam as well as screening for risk factors. An annual cardiac history and physical should be performed to check for new-onset heart problems.
Within 10 years of treatment, 10%-30% of patients who undergo radiation therapy develop radiation-induced heart diseases (RIHD), including chronic pericarditis, myocardial fibrosis, coronary artery disease, aortic calcification, and valve regurgitation or stenosis. The hope of screening is to catch early RIHD, but screening is not currently routine.
"We wrote the expert consensus to raise the alarm that the risks of radiation-induced heart disease should not be ignored. The prevalence ... is increasing because the rate of cancer survival has improved," said Dr. Patrizio Lancellotti, who is a professor of cardiology at the University Hospital of Liège, Belgium, and led the recommendations task force.
Radiotherapy is given in more targeted form and at lower doses than it once was, but "patients are still at increased risk of RIHD, particularly when the heart is in the radiation field. This applies to patients treated for lymphoma, breast cancer, and esophageal cancer. Patients who receive radiotherapy for neck cancer are also at risk because lesions can develop on the carotid artery and increase the risk of stroke," Dr. Lancellotti said in a statement.
Using targeted radiation and alternate radiation fields, with avoidance and shielding of the heart, remain "the most important interventions to prevent" cardiac complications, the authors noted.
The task force advises that high-risk patients without evidence of heart disease on history and physical should have screening echocardiography every 5 years and noninvasive stress testing every 5-10 years; low-risk patients should have screening echocardiography every 10 years. If heart disorders are detected, routine monitoring should include echocardiography, cardiac magnetic resonance imaging, or carotid ultrasound as appropriate.
High-risk patients include those who received radiotherapy at younger ages; those who have cardiovascular risk factors or preexisting heart disease; and those who receive high-dose radiation (greater than 30 Gy), concomitant chemotherapy, radiation without shielding, or anterior or left chest radiation (Eur. Heart J. Cardiovasc. Imaging 2013;14:721-40).
The recommendations are based on an extensive literature review and analysis by Dr. Lancellotti and other specialists.
The authors reported no financial conflicts or outside funding for their work.