Global longitudinal strain at 3 months after therapy can predict late cardiotoxicity in breast cancer.

Background: Cancer therapy-related cardiovascular toxicity (CTR-CVT) is a major contributor to poor prognosis in breast cancer (BC) patients undergoing chemotherapy. Left ventricular global longitudinal strain (LV GLS) has predictive value for CTR-CVT, while few researchers take into account late-onset CTR-CVT. This study sought to provide a guide for the prediction of late-onset CTR-CVT in primary BC over the 2 years follow-up via strain and contrast-enhanced echocardiography.

Methods: Anthracycline and anthracycline + targeted medication groups were created from 111 patients with stage I-III primary BC who were prospectively included. The left ventricular diastolic function, LV global long-axis strain (GLS); left ventricular ejection fraction by contrast-enhanced echocardiography (c-LVEF), and electrocardiograms were collected at baseline, 3, 6, 12, and 24 months after the start of cancer treatment. The high-sensitivity troponin-T and NT-pro BNP at baseline and 3 months after chemotherapy were measured.

Results: (1) LV GLS decreased in BC patients over time. (2) After 12 months' follow-up, the LV GLS in the anthracycline+ targeted group was lower than in the anthracycline group. After 24 months' follow-up, the GLS and c-LVEF in the anthracycline + targeted group declined while the E/e' increased. (3) Decreased LVEF (56%) and arrhythmia (38%) are the common causes of CTR-CVT. Lower LVEF was a major factor in late-onset CTR-CVT. (4) Combination of LV GLS and c-LVEF at 3 months were used as predictors for CTR-CVT and exhibited a higher AUC than either one alone (AUC = 0.929, 95% CI: 0.863-0.970). LV GLS at 3 months can predict the late-onset CTR-CVT (AUC = 0.745, p < 0.001), and the cut-off is 20.32%.

Conclusions: As time went on, the systolic and diastolic dysfunction of BC patients get worsened. The combination of LV GLS and c-LVEF is better in the prediction of CTR-CVT. Only the LV GLS at 3 months can predict the late-onset CTR-CVT.