Cancer survivors who had chest radiation are nearly twice as likely to die in the years after having major heart surgery as similar patients who did not have radiation, according to a study.
Chest radiation to kill or shrink breast cancer, Hodgkins lymphoma and other cancers increases survivors risk for major heart disease years — even decades — after radiation therapy, researchers reported in the April 9 issue of Circulation, an American Heart Association journal.
“While radiation treatments done on children and adults in the late 1960s, 70s and 80s played an important role in cancer survival, the treatment often takes a toll on the heart,” Milind Desai, MD, a study author and associate professor of medicine at the Cleveland Clinic, said in a news release.
“Survivors are at greater risk than people who do not have radiation to develop progressive coronary artery disease, aggressive valvular disease and pericardial diseases, which affect the hearts surrounding structures. These conditions often require major cardiac surgery.”
The study is described as the largest to examine how prior radiation affects long-term results from major heart surgery. The researchers reviewed 173 patients who had radiation treatment for cancer an average of 18 years before needing heart surgery. They followed the heart surgery patients an average of 7.6 years and compared them to 305 patients undergoing similar heart surgeries who did not have radiation therapy.
“These are major open-heart procedures, including valve or bypass procedures, and a vast majority had multiple simultaneous procedures, such as multiple valve surgeries or valve plus bypass,” Desai said. “About a quarter of the patients had redo surgeries, which puts them at even higher risk than those having the initial procedures.”
Radiation patients had similar pre-surgical risk scores to those who had not undergone radiation. Typically, preoperative risk scores help determine how patients will fare after surgery.
Patients had similar results in the first 30 days after major cardiac surgery regardless of their prior radiation status. However, during an average 7.6 years of follow-up, 55% of patients in the radiation group died, compared with 28% in the non-radiation group.
“These findings tell us that if you had radiation, your likelihood of dying after major cardiac surgery is high,” Desai said. “Thats despite going into the surgery with a relatively low risk score. In patients who have had prior thoracic radiation, we need to develop better strategies of identifying appropriate patients that would benefit from surgical intervention. Alternatively, some patients might be better suited for percutaneous procedures.”
The full study is available at http://circ.ahajournals.org/content/127/14/1476.full.