Background/Introduction: As the numbers of cancer survival increase, early detection and treatment of chemotherapy induced cardiotoxicity become more important.
Purpose: The authors investigated whether the structural and functional changes of the left atrium (LA) can be used as a predictor of future chemotherapy induced left ventricular dysfunction (LVD).
Methods: A total of 72 female breast cancer patients without chemotherapy-induced LVD on echocardiography at baseline and 6 months of follow up were included for this analysis. Echocardiography examinations were serially performed at baseline before the initiation of chemotherapy, at 6, 12, and 18 months of clinical follow up. Chemotherapy-induced LVD was defined as the development of LV ejection fraction (EF) <55% and the decrease in LVEF >10% from the baseline LVEF on follow up echocardiography at 12 or 18 months in the present study. Besides conventional echocardiographic measurements, global longitudinal strain (GLS) of the LA and the left ventricle (LV) were checked and compared.
Results: Chemotherapy induced LVD was developed 13 patients (18.1%), and LVEF was decreased (64.1±6.0 to 61.4±8.9%, p=0.001) over the follow up period. LA GLS gradually decreased (-25.4±1.4 to -21.1±2.4%, p<0.001) over the follow up period, and the decrease of LA GLS was more prominent in patients with chemotherapy-induced LVD than in patients without LVD (-25.8±1.3 to -17.8±1.9% vs -25.3±1.4 to -21.8±1.8%, p<0.001). LA end-systolic volume (50.2±5.7 to 51.5±6.4%, p<0.001) and E/E' (7.9±1.2 to 8.1±1.7%, p=0.047) were also increased during the 6-month follow up. LA GLS on follow echocardiography at 6 months were significantly lower in patients with chemotherapy induced LVD group than in patients without LVD (-21.9±1.3 vs -23.8±1.6, p<0.001). By receiver operation characteristic curve analysis, the optimal cutoff value for predicting upcoming chemotherapy induced LVD was LA GLS > -22.5% on 6-month follow up echocardiography (76.9% sensitivity and 71.2% specificity, AUC 0.829).
Conclusions: The present study demonstrated that structural and functional changes of the LA as measured by LA GLS precedes before developing overt chemotherapy induced LVD. Therefore, the serial measurement of LA GLS can be used as a useful parameter in the prediction of future chemotherapy induced cardiotoxicity.