Echocardiographic Risk Stratification in a General Oncology Population in Myanmar: A Prospective Observational Study

Background: Chemotherapy-related cardiac dysfunction (CTRCD) is a major cause of morbidity in cancer survivors. While global longitudinal strain (GLS) has shown promise in predicting cardiotoxicity, its utility has not been established in resource-limited settings like Myanmar, where the baseline burden of cardiovascular risk is high. Objectives: This study sought to determine the predictive value of baseline pre-chemotherapy echocardiographic parameters, particularly GLS, for the development of CTRCD in a diverse cohort of Myanmar patients with common solid tumors. Methods: We conducted a prospective, single-center, observational cohort study in Pyin Oo Lwin. We enrolled 150 chemotherapy-naïve adult patients with breast, cervical, lung, or other solid tumors scheduled to receive anthracycline- and/or trastuzumab-based therapy. All patients underwent baseline clinical assessment and comprehensive transthoracic echocardiography, including speckle-tracking for GLS. Patients were followed for 12 months with serial echocardiograms. The primary endpoint was CTRCD, defined as a decline in left ventricular ejection fraction (LVEF) by >10 percentage points to a value <53%. Results: Over 12 months, 23 patients (15.3%) developed CTRCD. In baseline analysis, patients who developed CTRCD had significantly worse mean GLS compared to those who did not (−17.8 vs. −20.1; p<0.001), while baseline LVEF was not significantly different. In multivariable logistic regression, an abnormal baseline GLS (defined as > −18%) was the only strong, independent predictor of CTRCD (Adjusted Odds Ratio: 4.0; 95% Confidence Interval: 1.6-9.9; p=0.003), after adjusting for age, hypertension, and cancer type. Subclinical LV dysfunction (relative GLS drop >15%) occurred in 40 patients (26.7%). Conclusions: In a Myanmar oncology cohort, baseline GLS is a powerful and independent predictor of subsequent cardiotoxicity, superior to baseline LVEF. Integrating pre-chemotherapy GLS into routine assessment could significantly improve risk stratification and guide preventative strategies in resource-limited settings.