Abstract 12101: Vectorcardiographic QRS and T Loop Roundness is Associated With Sudden Cardiac Death: The Atherosclerosis Risk in Communities and the Cardiovascular Health Study
Introduction: Vectorcardiography (VCG) analysis using QRS and T loop roundness has been shown to be associated with prior myocardial infarction, but their association with sudden cardiac death (SCD) remains unknown.
Hypothesis: We hypothesized that QRS and T loop roundness are independently associated with sudden cardiac death (SCD).
Methods: We prospectively analyzed reconstructed VCGs of 19,972 subjects at the baseline visit from the Cardiovascular Health Study (n=5374, age >65) and the Atherosclerosis Risk in Communities study (n=14,598, age 45-64). QRS and T loop roundness was measured by the roundness index (RI) and principal component analysis (PCA) ratio. We evaluated the association between these parameters and the risk of SCD using 3 multivariate Cox Models. Model 1 adjusted for demographic characteristics (age, sex, race, study center/cohort), model 2 additionally adjusted for prevalent cardiovascular disease (coronary heart disease, heart failure, stroke, atrial fibrillation, use of beta blocker) and traditional cardiovascular risk factors (BMI, hypertension, diabetes, smoking, alcohol, cholesterol, HDL, triglycerides, physical activity index, creatinine), and model 3 further adjusted for ECG parameters associated with SCD (heart rate, QRS QTc, sex-specific Cornell product, BBB/IVCD).
Results: Smaller QRS loop RI (SD) was independently associated with SCD in model 3 (HR 0.89 [95%CI 0.81-0.97]; p=0.01). Larger T loop RI (SD) was associated with SCD only in minimally adjusted model 1 (HR 1.14 [95%CI 1.06-1.23]; p=0.01). Larger T loop PCA ratio (SD) was associated with SCD in all three models (model 1, HR 1.32 [95%CI 1.23-1.43]; model 2, HR 1.16 [95%CI 1.07-1.25]; model 3, HR 1.11 [95%CI 1.03-1.20], all p <0.01).
Conclusions: Smaller QRS loop roundness and larger T loop roundness are associated with an increased risk of SCD. VCG analysis can help identify patients at increased risk of SCD.
Author Disclosures: T.V. Mai: None. M.M. Kabir: None. G. Sedeghat: None. J. Thomas: None. J.W. Waks: None. C.M. Sitlani: None. M.L. Biggs: None. C.A. Henrikson: None. N. Sotoodehnia: None. T. Biering-Sørensen: None. D.S. Siscovick: None. W.S. Post: None. E.Z. Soliman: None. S. Solomon: None. A.E. Buxton: None. M.E. Josephson: None. L.G. Tereshchenko: None.
- © 2016 by American Heart Association, Inc.