Changes of Left Atrium Structural and Functional Parameters in Patients Undergoing Anthracycline Therapy: A 6-Month Follow-up Cmr Study in Breast Cancer Patients

Introduction Cardiotoxicity remains a significant concern as breast cancer treatments continue to improve [1]. Cardiac magnetic resonance (CMR) offers additional measurements, including multiparametric tissue characteristics and deformation, which can show subtle changes in myocardial function [2]. Recent evidence indicates that the changes in the left atrium (LA) may also be one of the early subclinical signs of cardiotoxicity [3]. Aim This study aimed to evaluate early morphometric and functional changes of LA in patients undergoing potentially cardiotoxic anthracycline treatment for breast cancer and compare them to LV functional parameters. Methods Fifty-five women undergoing breast cancer treatment with anthracyclines were included in the study. CMR was performed before starting cardiotoxic therapy and three and six months after the initiation of treatment. The CMR images were analyzed using dedicated postprocessing software (Medis Suite MR, The Netherlands). Using the longaxis cine images, LA volume (LAV), LA area (LAA), LA emptying fraction (LAEF) (normal range 46–78% [4]) and LA strain (LAS), as well as LV global longitudinal strain (LVGLS), were calculated. LV ejection fraction (LVEF) was estimated using stack of short-axis CMR images. LA volume and area were indexed to body surface area. Statistical analysis was performed using the IBM SPSS 29.0 package. Results The mean age of the participants was 54 ± 10 years. The statistical analysis of LV function indicated a statistically significant decrease in LVEF over 6 months from 66,79 ± 5,30 % at baseline to 62,91 ± 5,79 % at the 6-month followup (p = 0,001), but remaining in normal range (higher than 55%). The change in LVGLS did not reach statistical significance (p = 0,297). The analysis revealed that the change in LAA (22,64 ± 4,17 cm2 vs. 21.95 ± 4,89 cm2 vs. 22,77 ± 4,77 cm2, p = 0,690) and LAAi (12,13 ± 2,01 cm2 /m2 vs. 12,03 ± 2,57 cm2 /m2 vs. 12,26 ± 2,19 cm2 /m2 ; p = 0,873) during 6 months period was not significant, nor were the changes in LAV (74,43 ± 19,22 ml vs. 70,58 ± 22,84 ml vs. 73,05 ± 23,71 ml; p = 0,453) and LAVi (40,25 ± 8,90 ml/m2 vs. 38,91 ± 11,34 ml/m2 vs. 39,21 ± 11,58 ml/m2 ; p = 0,431). The LAEF showed a statistically significant decrease between the baseline and 6-month followup (57,48 ± 9,70 % to 54,45 ± 8,17 %, p = 0,028). The LAS value had also decreased from 35,95 ± 12,01 at baseline to 30,26 ± 8,21 at the 6-month follow-up (p = 0,003), with the most significant changes occurring between the 3- month follow-up (35,41 ± 8,92) and the 6 month follow up (p = 0,002). Moreover, a moderate positive correlation was observed between LAV and LVGLS (r = 0,338, p < 0,001) and between LAV and LVEF (r = 0,338, p < 0,001), indicating a relevant link in LA volumetric and LV functional measurements. Conclusions LA functional measures decreased early, suggesting they could be one of the first markers of decreasing heart function and require further investigation.