Correlation between basic cardiac function and acute radiation-induced heart injury

Abstract

Objective To investigate the correlation between basic cardiac function and acute radiation-induced heart injury, and evaluate the changes of cardiac function of patients with acute stage radiation injury. Methods A total of 109 patients with thoracic tumor underwent radiation therapy. Changes of basic cardiac function before, after, and within the first 3 months of radiation were recorded respectively. Effects of radiation on cardiac function and incidence of acute radiation-induced heart injury were analyzed. Results The overall incidence of acute radiation-induced heart injury was 79.8%, with no significant correlation with basic cardiac function (P>0.05). In acute stage post radiation injury, there were 24 cases of decreased left ventricular diastolic function and 15 cases of decreased systolic function were found respectively. All 24 cases of cardiac valve injury presented with mitral valve and (or) aortic valve damage, including 23 reflux (mild and moderate degree) and 1 stenosis (mild degree), whereas no tricuspid and (or) pulmonary valves injuries were observed. Fore-and-aft pathways of left atria, flow velocities of aorta, and E/A values were all significantly different either after or within the first 3 months of radiation(F=8.552, 0.017, 0.003, P<0.05). Compared with pre-radiation values, the above three parameters decreased by 9.19%, 7.56% and 17.5% respectively post-radiation, and recovered by 7.05%, 4.14% and 7.58% at the time within the first 3 months. Moreover, E/A values showed the greatest degree of change. Conclusions Neither clinical features nor basic cardiac function is associated with acute RIHD. Radiation induce mild reflux of bicuspid valves and aortic valves are more common in patients that receive thoracic radiation. Fore-and-aft pathways of left atria, flow velocities of aorta, and E/A values first reduce at the end of the radiation treatment and then gradually recovered, but are unable to return to basic levels in the acute stage. Acute radiative effects on cardiac diastolic function are more significant than those on systolic function. Key words: Thoracic neoplasm; Radiotherapy; Acute radiation-induced heart injury; Cardiac function