The spatial QRS-T angle is a measure of repolarization heterogeneity and may be a predictor of poor ventricular health. It is unknown whether a relationship exists between QRS-T angle and blood pressure (BP) during exercise.
The purpose of this study was to evaluate the potential relationship between QRS-T angle and BP during exercise, which may be indicative of ventricular stretch.
Ambulatory 12-lead 24-hour Holter electrocardiographic monitoring for QRS-T angle measurement was followed by exercise testing with BP (mm Hg) recordings taken preexercise, maximum achieved BP during exercise, and 2 minutes postexercise. Blood pressure recovery was calculated by subtracting the maximal and 2-minute postexercise BPs. Means (± standard deviation) and percentages are presented. Pearson correlations (r) among all QRS-T angles and all BP measures were performed. One-way analysis of variance was conducted on classification of QRS-T angle and all BP measures.
One hundred eleven firefighters (95.5% male; mean age, 44 years) were included in this analysis. Twenty-seven percent of the firefighters had either a borderline (100°–139°) or widened (≥140°) QRS-T angle. Although the analysis of variance was not statistically significant, a near–statistically significant negative correlation existed between QRS-T angle and maximum diastolic BP (r = −0.190, P = .05), and a statistically significant relationship existed between QRS-T angle and postexercise diastolic BP (r = −0.261, P = .008).
A negative correlation existed between QRS-T angle and maximal diastolic BP and postexercise diastolic BP. Lower maximum diastolic BP during and after exercise may be a sign of poor ventricular stretch. A widened spatial QRS-T angle may represent poor ventricular stretch.
Dillon J. Dzikowicz, BS, RN Doctoral (PhD) Student, School of Nursing, University of Rochester, New York.
Mary G. Carey, PhD, RN, FAHA, FAAN Associate Professor, School of Nursing, University of Rochester, New York.
This study was supported by a grant from the National Institutes of Health, R21 NR-011077 (M.G.C.).
The authors have no conflicts of interest to disclose.
Correspondence Dillon J. Dzikowicz, BS, RN, School of Nursing, University of Rochester, 255 Crittenden Blvd, Rochester, NY 14642 (Dillon_Dzikowicz@URMC.Rochester.edu).