Global Longitudinal Strain as a Surveillance Tool in Hematologic Cancer-Related Cardiotoxicity

Advances in the treatment of hematologic malignancies have significantly improved survival, leading to an increasing burden of cancer therapy-related cardiac dysfunction (CTRCD). Early detection of cardiotoxicity is critical, as conventional measures such as left ventricular ejection fraction often identify myocardial injury only after irreversible damage has occurred. Global longitudinal strain (GLS), derived from speckle-tracking echocardiography, has emerged as a sensitive and reproducible tool for detecting subclinical myocardial dysfunction. This review summarizes the role of GLS in the surveillance of cardiotoxicity in patients with hematologic malignancies. We discuss the pathophysiological basis of chemotherapy-induced myocardial injury, including oxidative stress, mitochondrial dysfunction, and inflammatory mechanisms. Evidence supporting GLS as a predictive and monitoring tool is examined across baseline risk stratification, treatment-related changes, and long-term outcomes. GLS consistently demonstrates earlier detection of myocardial dysfunction compared with left ventricular ejection fraction and provides prognostic value in diverse therapeutic settings, including anthracycline-based chemotherapy, hematopoietic stem cell transplantation, and novel immune-based therapies. The integration of GLS into cardio-oncology practice, particularly in combination with cardiac biomarkers, enhances early detection and risk stratification. Despite limitations such as intervendor variability and lack of standardized thresholds, GLS is increasingly incorporated into guideline-recommended surveillance strategies.