Study of effects of anthracycline drugs on myocardial function in breast cancer patients by quantitative analysis of layer-specific strain via 2D-STI technology.

ABSTRACT

OBJECTIVE: This study aimed to explore the value of layer-specific strain analysis by two-dimensional speckle tracking imaging (2D-STI) in the assessment of myocardial toxicity in breast cancer patients receiving anthracycline chemotherapy. METHODS: Thirty-four breast cancer patients receiving anthracycline chemotherapy were prospectively enrolled. Conventional echocardiography and 2D-STI were evaluated at baseline after the third and sixth cycles of anthracycline chemotherapy. The strains of different layers of left ventricle (LV) including peak systolic longitudinal strain (endo-LS, mid-LS, epi-LS) and circumferential strain (endo-CS, mid-CS, epi-CS) were measured using EchoPAC analysis software. Peak systolic longitudinal strain (MV-LS, PM-LS, AP-LS), circumferential strain (MV-CS, PM-CS, AP-CS) and radial strain (MV-RS, PM-RS, AP-RS) were measured at mitral valve, papillary muscle and apex levels of LV respectively. Global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and left ventricular twist (LVtw) were also analyzed. RESULTS: There was no significant difference in the structural and functional parameters of conventional 2D echocardiography in different cycles of anthracycline chemotherapy (P>0.05); layer specific LS and CS in various cycles decreased layer by layer from inside to outside. LS and CS increased from basal segment to apical segment, while RS showed no obvious gradient characteristics; compared with baseline, GLS and LSs (endo-PM, endo-AP, mid-PM, mid-AP and epi-AP) of LV decreased significantly after the third cycle of chemotherapy (P<0.05); LSs (epi-MV and epi-AP) decreased significantly after the sixth cycle of chemotherapy (P<0.05). No significant changes were detected in layer specific CS, RS and LVtw (P>0.05). CONCLUSION: Layer-specific strain analysis by 2D-STI technology can quantitatively analyze global and regional functions of LV. The myocardial toxicity due to anthracycline chemotherapy can be detected by layer-specific LS of LV in early stage, which is great valuable to guiding clinical early intervention and improving prognosis.