LAUSR

Objective Frontal plane QRS-T (fQRS-T) angle is a marker of ventricular repolarization heterogeneity and increased fQRS-T angle is associated with arrhythmias, adverse events and mortality. However, little is known about the importance and usefulness of fQRS-T angle in hypertensive patients. The present study aimed to investigate the association between blood pressure (BP) levels and fQRS-T angle. The main goal was to demonstrate whether BP lowering has a favorable effect on fQRS-T angle in hypertensive patients. Methods This study included 392 newly diagnosed hypertensive patients who underwent antihypertensive therapy. Responders and nonresponders to antihypertensive therapy were compared regarding baseline and post-treatment fQRS-T angle. fQRS-T angle was calculated as the absolute difference between QRS and T wave axes that were obtained from electrocardiography. Response to treatment was defined as achieving BP levels <140/90 mmHg. Results At the 1-month follow-up visit, responders had significantly lower fQRS-T angle compared to nonresponders despite the similar baseline fQRS-T angle (baseline: 57° ± 18.2° vs.56.6° ± 16.3°; P = 0.819, at 1 month: 36.9° ± 13.7 vs.53.5° ± 15.6°; P < 0.001). Moreover, after 3 months of antihypertensive treatment, both responders at 1 month and 3 months had significantly lower fQRS-T angle compared to nonresponders (34.8° ± 13.3° vs. 35.4° ± 12.9° vs. 52.3° ± 13.9°; P < 0.001). Furthermore, a significant moderate positive correlation was observed between systolic BP and fQRS-T angle (r:0.797; P < 0.001), and between diastolic BP and fQRS-T angle (r:0.761; P < 0.001). Conclusion In the present study, a significant decrease in fQRS-T angle was observed following BP lowering throughout the study period. Therefore, fQRS-T angle may be useful in the monitoring of antihypertensive treatment.