Abstract
Objectives: To study the characteristics of arrhythmia and electrocardiographic changes in breast cancer patients receiving chemotherapy with an anthracycline regimen.
Subjects and methods: The study was conducted on 52 breast cancer patients treated at Phu Tho Provincial General Hospital from August 2021 to September 2022 who received chemotherapy with Doxorubicin and had an holter electrocardiogram. 12-lead ECG before and after four chemotherapy cycles, just before the fifth.
Results: There was a statistically significant difference (p < 0.05) in the status of arrhythmias in general between the two times of Holter recording and the latter (after treatment) with the proportion of patients having arrhythmias. Heart rate is higher than the first record (59.6% vs. 55.8%). The thick ACT regimen had a higher risk of arrhythmia than the ACT regimen with an OR=5,225. The age group over 50 had a lower risk of arrhythmia than those under 50, with an OR = 0.194. The mean heart rate between the two-time points of electrocardiogram recording had a statistically significant difference (p = 0.006). There was a significant prolongation of the QT and Tp-e interval after cycle 4 (p=0.001 and p=0.002). The amplitude of the T wave also recorded a significant change when the T wave tended to flatten after treatment (p = 0.004). Meanwhile, the P, PR, and QRS intervals do not change.
Keywords: Cardiac arrhythmia, ECG changes, breast cancer, Anthracycline.