Assessment of Interventricular Septum and Left Ventricular Posterior Wall Thickness Changes Following Radiotherapy in Breast Cancer Patients Using Echocardiography

Abstract

Background: Radiotherapy (RT) is an essential component of breast cancer management but the associated cardiac exposure to radiation may lead to cardiac damage. That could be assessed using echocardiogram. Purpose: This study aims to evaluate changes in interventricular septum (IVS) and left ventricular posterior wall (LVPW) thickness post-radiotherapy in breast cancer patients and assess the relationship between the radiation laterality to these changes. Methods: this prospective cohort study conducted at Al-Najaf Center for Cardiac Surgery and Transcatheter Therapy, Al-Sader Teaching Hospital in Al-Najaf city from January to September 2025.It involved evaluation of 40 females with breast cancer between the ages of 20 and 65 years. They were divided into two groups: left sided breast cancer(n=18) and right sided breast cancer (n=22). Interventricular septum thickness and left ventricular posterior wall thickness were measured using standard 2D transthoracic echocardiography before and within10 days following completion of radiotherapy. Independent t-test and paired t-test were used for statistical comparisons. Results: Compared to pre-radiotherapy, post-radiotherapy mean of left ventricular inter ventricular septum thickness was significantly increased. The same changes seen for left ventricles posterior wall thickness, it was significantly increased following radiotherapy. The increment post radiotherapy was higher in left sided radiotherapy compared to right sided for IVS thickness and LVPWT. Hypertensive patients and those aged 50+ years reported a higher increment post radiotherapy of both IVS thickness and LVPWT. Implications: results support involvement of echocardiographic wall thickness measurement in the post-radiotherapy monitoring protocols, especially for high-risk patients. Future studies with follow-up for longer time, and are recommended to identify long-term clinical implications. Additional materials: the manuscript includes 12 references and 5 tables. Conclusion: Increased IVS thickness and LVPW thickness are manifestations of subclinical myocardial remodeling, that develop soon after breast cancer radiation therapy.