부산대학교 도서관

Background: The spatial QRS-T angle (spQRSTa) has been studied as prognostic factor for cardiovascular (CV) events and mortality. To gain more insight in mechanisms involved in spQRSTa widening, we investigated associations between CV risk factors and the spQRSTa, as well as associations of carotid intima-media thickness (cIMT), as marker of subclinical atherosclerosis, and pulse wave velocity (PWV), as marker of arterial stiffness, with the spQRSTa. Methods: We performed cross-sectional analyses within the Netherlands Epidemiology of Obesity Study cohort (n=6,671). Participants with missing spQRSTa measurements or electrocardiographic evidence of atrial flutter, fibrillation or other arrhythmias were excluded. SpQRSTa was determined from 12-lead ECGs, cIMT was assessed with ultrasonography and PWV with velocity-encoded MRI. Risk factors were assessed over three groups of spQRSTa, based on sex-specific percentiles (p95). Associations of cIMT and PWV with spQRSTa were investigated using linear regression analysis. Ability of spQRSTa to discriminate between normal and high (>p75, p95 or p99) cIMT or PWV was assessed using the c-statistic. Results: We included 6,342 participants, of whom 6,278 had cIMT and 2,369 PWV measurements. Several CV risk factors were associated with a wider spQRSTa. Compared with participants with a normal glucose metabolism (mean spQRSTa: 54°), spQRSTa was wider in participants with impaired (58°) or high (66°) fasting glucose, or type II diabetes mellitus (T2DM) (61°). Greater cIMT and PWV were associated with wider spQRSTa in crude models (difference in spQRSTa per SD cIMT: 2.7°, 95%CI: 1.6 – 3.8; PWV: 2.9°, 1.3 – 4.4), but not after adjustment for CV risk factors (cIMT: 0.5°, -0.7 – 1.6; PWV: 0.6°, -1.3 – 2.4). SpQRSTa was not useful in discriminating between normal/high cIMT or PWV. Conclusions: Several CV risk factors were associated with wider spQRSTa, and a wider angle was found in participants with impaired fasting glucose or T2DM, compared with normal glucose metabolism. Also, associations between greater cIMT and PWV and wider spQRSTa were present. These findings may partly explain that spQRSTa, an electrocardiographically and cheaply determinable variable, is a prognostic factor for adverse CV outcomes. [ABSTRACT FROM AUTHOR]