The change in Left Atrial Strain function among patients with breast cancer treated with anthracycline therapy

Background: Cardio toxicity has become a significant adverse effect of cancer therapy, with Doxorubicin in particular. Currently, cardio toxicity is defined by systolic dysfunction, evaluated by either left ventricular (LV) ejection fraction or LV global longitudinal strain (LVGLS). There is a crucial need for new imaging techniques for the early subclinical detection of cardio toxic effect. The use of left atrial strain (LAGLS) has been proven to correlate with morbidity among the general population; however, its use among patients with cancer is limited.

Objective: To evaluate the correlation between LAGLS, LV systolic and diastolic parameters and whether significant reduction in LAGLS is observed during Doxorubicin therapy.

Methods: Data were prospectively collected as part of the Israel Cardio-Oncology Registry (ICOR). All patients with breast cancer, planned for Doxorubicin therapy were included. All women underwent serial echocardiography including baseline LAGLS (before chemotherapy, T1) and after the completion of Doxorubicin therapy (T3). LAGLS was assessed in 3 phases: Reservoir (LAGLSr), Conduit (LAGLSc) and Pump (LAGLSp). Significant reduction in LAGLSr was determined by either a relative reduction of > 10% or an absolute value of <35%.

Results: From September 2016 to June 2019, forty patients were evaluated with a mean Doxorubicin dose of 237±13.24mg/m2. LAGLSr showed significant correlation to diastolic parameters. At T3, significant reduction in LAGLSr was observed among 50% of the patients with an average LAGLSr reduction from 40.15±6.83 to 36.04±7.73 (p<0.001). LAGLSc showed significant reduction as well (p<0.004) as opposed to LAGLSp (p=0.076). Twenty five percent of the patients showed systolic dysfunction at T3 with LVGLS relative reduction of > 15%, however no statistical significance was observed (p=0.957).

Conclusions: LAGLSr showed significant correlation to diastolic parameters with a significant reduction during Doxorubicin therapy, exceeding the reduction in LV systolic function, suggesting its benefit for early detection of cardio toxicity.