Effect of Cardiac Rehabilitation Program on left Ventricular Systolic Function in Patients with Breast Cancer receiving Anthracycline-based Chemotherapy Using Two-dimensional Speckle Tracking Echocardiography

Objectives: Anthracyclines used in the treatment of breast cancer are known for their cumulative cardiotoxic effect. Two-dimensional speckle tracking echocardiography is a promising technique in detection of subclinical cardiotoxicity. Cardio-oncology rehabilitation is a new field aiming to decrease the risk of cardiovascular diseases and improve cardiopulmonary fitness among cancer patients. Methods: The study included 100 female patients with de novo breast cancer and treated with anthracycline-based chemotherapy. Patients were randomly assigned into two groups in a 1:1 ratio. Group (1) included patients who were allocated to cardiac rehabilitation program in addition to their regular chemotherapeutic drugs and group 2 included patients who received chemotherapy only. Standard 2-dimensional echocardiography and 2-dimensional speckle tracking echocardiography for assessment of left ventricle global longitudinal strain were performed to all patients before receiving the chemotherapy and at 3 and 6 months after. Results: At 3 months, no significant difference was found between Group 1 and Group 2 as regards the left ventricular ejection fraction and left atrial volume Index. However, a significant difference was observed as regards E/E' (5.25 (4.5-5.5) in group 1 versus 7.5 (5-9.5) in group 2 with P value ≤ 0.01) and also in the average global longitudinal strain between the 2 groups; (-18.81 ± 1.39 in group 1 vs. -18.21 ± 1.43 in group 2, P = 0.092). At 6 months, Ejection fraction showed a significant difference between the 2 groups (64.10 ± 3.52 in group 1 vs. 59.46 ± 5.57 in group 2, P ≤ 0.01) which was also accompanied by a significant change in average global longitudinal strain (-18.91 ± 1.39 in group 1 vs. -17.89 ± 1.54 in group 2, P = 0.001). As regards cardiotoxicity (defined as ≥15 % change in average global longitudinal strain), there were no cases detected in group 1 despite the presence of 4 cases (8 %) in group 2 with a mean change of global longitudinal strain (16 %). Conclusion: Cardiac rehabilitation program has a protective role against chemotherapy-induced cardiotoxicity in patients with breast cancer.