Elevated Frontal QRS–T Angle as a Predictor of Cardiovascular Risk in Graves ’ Disease: A Comparative Study

Abstract Purpose Graves' disease (GD) is linked to cardiovascular complications, but reliable non-invasive predictors are limited. This study aimed to assess whether the frontal QRS-T (fQRS-T) angle could predict mortality and cardiovascular outcomes in GD patients. Methods Initially, we conducted a retrospective analysis of electrocardiogram (ECG) parameters from 291 GD patients compared with 96 healthy controls. GD patients were then categorized based on the presence of hyperthyroid heart disease. Using logistic regression, we identified predictors of cardiovascular outcomes. Subsequently, a retrospective cohort study followed 41 patients with an fQRS-T angle ≥90° and 82 matched controls over five years, assessing all-cause mortality and ventricular fibrillation (VF) using Kaplan-Meier analysis. Results Initial analysis showed that a significantly higher proportion of GD patients had an fQRS-T angle ≥90° compared to healthy controls (p< 0.001). Among GD patients, those with hyperthyroid heart disease were more likely to have an fQRS-T angle ≥90° (p < 0.001). Multivariate logistic regression analysis revealed that age, fQRS-T angle, thyroxine (T4), and platelet were independent predictors of hyperthyroid heart disease. In the cohort study, 41 GD patients with an fQRS-T angle ≥90° were selected as the exposure group, and 82 patients without a widened angle were selected as controls. Kaplan-Meier analysis demonstrated a significant difference in event-free survival between the groups, as assessed by log-rank test(P=0.001). Conclusion An increased fQRS-T angle is significantly associated with higher mortality and cardiovascular risk in GD patients. Measuring the fQRS-T angle could enhance risk stratification and guide clinical management in this population