Predictive value of post systolic shortening by two-dimensional speckle tracking echocardiography on cardiac injury in the breast cancer patients after chemotherapy / 中华超声影像学杂志

ABSTRACT

Objective:To assess the prognostic potential of post systolic shortening (PSS) on cardiac injury in the breast cancer patients after chemotherapy.Methods:This was a prospective cohort study in breast cancer patients after chemotherapy who were followed up to observe the risk of cardiac injury. A total of 69 female patients with HER-2 negative breast cancer were selected in the Fourth Hospital of Hebei Medical University from February to August 2019. The post-systolic strain index (PSI) of each segment of left ventricular myocardium after chemotherapy was obtained by two-dimensional speckle tracking echocardiography. PSI (%) was defined as follows [(peak strain in cardiac cycle-peak strain in systole)/peak strain in cardiac cycle]×100%. PSS was regarded as meaningful if PSI >20%. End point was cardiac injury, which could be manifested as cardiotoxicity, cardiogenic death, myocardial infarction, unstable angina pectoris, and severe arrhythmias. Occurence of any above mentioned cardiac injuries was considered as end point event. According to the number of myocardial walls with PSS, the patients were divided into three groups group A (no walls), group B (1 wall), and group C (≥2 walls). Additionally, the patients were also stratified according to tertiles of PSI layer A (the first tertile), layer B (the second tertile), and layer C (the third tertile).Results:During a median follow-up of 18 months (Q 1=17 months, Q 3=18 months), 17 patients (24.64%) were diagnosed as having end point events. The risk of end point increased with the increase in the number of myocardial walls with PSS and the increase in PSI stratification.After adjusting for age, hypertension, systolic blood pressure, global longitudinal strain, and E peak of mitral early diastolic inflow velocity/average peak early diastolic mitral annular velocity e′ (E/e′), the association remained significant, (Per 1 increase in number of walls with PSS, hazard ratio, 1.96, P=0.007. Per 1% increase in PSI, hazard ratio, 1.44, P<0.001). In terms of predictive ability, the Harrell′s C index of PSS and of PSI was 0.70 and 0.73, respectively, both P<0.01, which indicated moderate accuracy. Conclusions:The presence of PSS in breast cancer patients after chemotherapy can provide independent prognostic information for the future occurrence of cardiac injury.