Effect of anemia on the frontal QRS-T angle.

BACKGROUND: Anemia is a common health problem worldwide and is associated with a poor prognosis for cardiovascular diseases. It can alter myocardial depolarization and repolarization by affecting the generation and propagation of electrical impulses. The frontal QRS-T angle is a novel marker of the absolute difference between myocardial depolarization and repolarization. This study investigated the effects of anemia on the frontal QRS-T angle. METHODS: The study included 66 anemic subjects with no cardiac disorders, and 50 age- and gender-matched controls. Twelve-lead electrocardiography (ECG) was obtained for all subjects, and the frontal QRS-T angle was calculated based on the automatic report of the ECG machine. RESULTS: Subjects with anemia had a significantly higher frontal QRS-T angle than subjects without anemia (28.9 +/- 14.1 vs. 22.5 +/- 11.8, p = 0.011). In correlation analysis, the frontal QRS-T angle was positively correlated with the body mass index (BMI; r = 0.287, p = 0.002), left ventricular mass (LVM; r = 0.264, p = 0.004), and heart rate (r = 0.275, p = 0.003) and negatively correlated with the hemoglobin level (r = -0.349, p < 0.001). Multivariate regression analysis showed that the hemoglobin level (beta = -0.254, tbeta = -2.805, p = 0.006), BMI (beta=0.240, t=2.770, p=0.007), and LVM (beta=0.201, t=2.303, p=0.023) were independently associated with the frontal QRS-T angle. CONCLUSIONS: The hemoglobin level was found to be an independent predictor of the frontal QRS-T angle.