Left ventricular diastolic function in patients with breast cancer treated with anthracycline-based chemotherapy

Abstract

Abstract Background Despite major progress in novel breast cancer therapeutic regimens, anthracycline-based chemotherapy (ANT) remains among the most effective therapies. Cardiotoxicity, one of the most severe adverse events of ANT, has been defined as a reduction in left ventricular ejection fraction (LVEF) or global longitudinal strain (GLS). However, the role of early diastolic dysfunction has been insufficiently researched. We aimed to determine if diastolic dysfunction could early diagnose and predict ANT cardiotoxicity. Methods Studies that reported on echocardiographic parameters of diastolic function before and at the end of ANT in breast cancer patients without cardiac disease were included. We evaluated parameter derived from pulsed wave Doppler interrogation of the mitral valve inflow (E/A ratio and mitral E-wave deceleration time (EDT)) and tissue Doppler (mean velocities of the mitral ring in the early diastole (E') and E/E' ratio). Results A total of 892 patients from 13 studies were included. E/A ratio was significantly reduced at the end of ANT (OR 2.34, 95% CI [1.49, 3.68], p<0.001), while EDT was not significantly influenced (OR 0.74, 95% CI [0.50, 1.08], p=0.121). Tissue Doppler velocity of the mitral ring E' and the LV filling pressure analysed through E/E' ratio did not show significant changes after ANT (OR 2.32, 95% CI [0.94, 5.72], p=0.068, and OR 0.79, 95% CI [0.56, 1.12], p=0.197, respectively). A modest reduction in LVEF and global longitudinal strain (GLS) was observed at the end of the ANT therapy with a difference in means of 3.77% and −1.08%, respectively. Patients receiving ANT doses over 400 mg/m2 doxorubicin or epirubicin therapeutic equivalent doses showed a significant change in E/A and E' after the therapy. Cardioprotective therapy like carvedilol, nebivolol and spironolactone did not have a significant impact on the parameter of diastolic function. Conclusion ANT has a modest early impact on LV diastolic function in patients with breast cancer without cardiac disease and cannot be validated as an early diagnostic or prognostic tool of ANT-induced cardiotoxicity. Randomized studies on larger population, using new parameter e.g. left atrial function parameter and multimodality imaging are required. Funding Acknowledgement Type of funding sources: None.