Vol. 7, Issue 2, Part A (2025)

Aims: To evaluate the utility of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and global longitudinal strain (GLS) measured via echocardiography for the early detection of subclinical cardiotoxicity in breast cancer patients undergoing anthracycline-based chemotherapy.
Methods: This prospective observational study included a total of 100 breast cancer patients (aged ≥18 years, LVEF ≥50%) scheduled to receive anthracycline-based adjuvant chemotherapy were enrolled. Exclusion criteria included prior chemotherapy or radiotherapy, significant cardiac disease, or poor echocardiographic windows. Baseline and post-chemotherapy (12 weeks) measurements included 2D-transthoracic echocardiography for GLS (average, 4C, 3C, 2C), LVEF, E/e’, and NT-proBNP levels. Cardiotoxicity was defined by relative reductions in GLS ≥8% and changes in NT-proBNP and EF. Statistical analyses included paired t-tests and Pearson correlation.
Results: Post-chemotherapy, there was a significant decline in average GLS (from -20.9±1.8 to -19.8±2.2; p<0.001) and a rise in NT-proBNP levels (from 67.6±24.3 to 154.2±109.2 pg/mL; p<0.001), indicating early myocardial stress. Ejection fraction decreased (from 62.7±3.1 to 59.2±4.6; p<0.001), and E/e’ increased (from 11.5±1.5 to 12.8±1.5; p<0.001). A relative GLS reduction ≥8% was observed in 22 patients and was associated with higher changes in NT-proBNP (median: -109 vs. -48.3; p<0.001) and EF (median: 4 vs. 2; p<0.001). NT-proBNP correlated significantly with GLS (r=0.512), E/e’ (r=0.394), and EF (r=-0.644); p<0.001.
Conclusion: NT-proBNP and GLS are sensitive, non-invasive markers for detecting early subclinical cardiotoxicity in breast cancer patients receiving anthracycline chemotherapy. Their integration into routine cardiac monitoring can enable timely identification and intervention, potentially preventing progression to overt heart failure. Further large-scale, long-term studies are warranted to validate these findings and establish standardized protocols.