Patients with breast cancer receiving radiation therapy demonstrated moderate changes in their cardiac function over a period of several years, and patients who received a maximum left anterior descending artery dose had a modest worsening in both systolic and diastolic function, according to the results of a longitudinal cohort study published in JACC: CardioOncology.
“Our findings provide reassurance as to the lack of overt, clinically substantial detrimental changes in left ventricular ejection fraction (LVEF) in the intermediate term following [radiation therapy] for breast cancer, likely secondary to the low heart dose,” Eva Berlin, MD, and colleagues wrote. Dr. Berlin is from the Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania.
Study Methods and Results
The study authors sought to determine the cardiac morbidity associated with radiation treatment for breast cancer. They conducted a longitudinal cohort study of 303 women with breast cancer who had received adjuvant radiotherapy and were followed for a median of 5.1 years. The participants received a median mean radiation dose to the heart of 1.19 Gy.
Over the 5 years, a slight increase was reported in LVEF (52.1% to 54.3%; P < .001) and a modest worsening of sensitive function measures, including circumferential strain (–23.7% to –21.0%; P = .003).
In patients with left-sided or bilateral breast cancer, changes in cardiac function were observed across all parameters (P < .05).
Patients who received a maximum dose to the left anterior descending artery showed modest worsening of LVEF, longitudinal strain, circumferential strain, and in the ratio of early diastolic mitral inflow velocity to early diastolic mitral annular tissue velocity.
“Our results also suggest that changes in diastolic function, strain, and ventricular-arterial coupling are observed following radiotherapy, potentially providing early indication of the subsequent risk of early heart failure with preserved ejection fraction. Finally, our data also support the importance of dose to the left anterior descending artery and motivate additional science to improve contouring of the left anterior descending artery and associated substructures,” the study authors summarized.
Disclosure: For full disclosures of the study authors, visit jacc.org.
