Abstract 15966: Frontal QRS-T Angle: Normal Range for Latinos and Association of an Abnormal Angle With Comorbidities
Introduction: Frontal QRS-T angle has been shown to be a predictor of all-cause mortality in patients with cardiac disease and even among the general population. There is heterogeneity in the definition of the cut-offs of QRS-T angle in different studies, and the normal range of this angle in each population may be different. Our aim is to determine the normal range of frontal QRS-T angle in Latinos and to investigate the association of an abnormal angle with comorbidities.
Methods: Retrospective, observational study, which assessed all digital electrocardiograms (ECGs) of primary care patients of the database of a public telecardiology service in Minas Gerais, Brazil, from January 2010 to January 2015. Comorbidities and medications were self-reported. ECGs with technical problems or from repeated patients were excluded. The University of Glasgow ECG analysis program was used to automatically interpret the exams. Frontal QRS-T angle was calculated, and the 98th percentile (P98) from the healthy population (defined as individuals without major ECG abnormalities, comorbidities and use of medications) was used as the reference value to define an abnormal angle. To assess the relation between comorbidities and abnormal QRS-T angle in the entire sample, unadjusted and adjusted odds ratios (OR) were estimated by logistic regression.
Results: A total of 1,087,337 ECGs were studied, 59.1% women, mean age 49±19 years-old, 44.7% from a healthy population. Hypertension was reported in 28.4%, diabetes in 5.2%, Chagas disease (ChD) in 1.8%, chronic obstructive pulmonary disease (COPD) 0.5%, chronic kidney disease in 0.4%, previous myocardial infarction (MI) in 0.6% and 6.2% were smokers. The frontal QRS-T angle P98 in the healthy population was 87 degrees, and in the entire sample 10.33% had QRS-T angle ≥ 87 degrees. Multivariate logistic regression showed that ChD (OR 2.94 [95% confidence interval 2.84-3.01]); previous MI (OR 1.72 [1.61-1.82]); diabetes (OR 1.25 [1.22-1.28]); hypertension (OR 1.22 [1.21-1.24]); COPD (OR 1.17 [1.09-1.26]) were independent predictors of an abnormal frontal QRS-T angle.
Conclusions: We provided reference values for QRS-T angle for Latinos. ChD and MI had the strongest association with abnormal frontal QRS-T angle.
Author Disclosures: M.S. Marcolino: None. E.A. Carvalho: None. T.M. Santos: None. D.M. Palhares: None. A.L. Ribeiro: None.
- © 2016 by American Heart Association, Inc.