Abstract 11486: Velocity of the Heart Vector Through the QRS Complex Predicts Sudden Cardiac Death in Cardiovascular Disease-Free Adults
Introduction: The majority of sudden cardiac deaths (SCDs) occur due to ventricular arrhythmia as the first manifestation of the coronary heart disease (CHD) in the general population.
Hypothesis: We hypothesized that velocity of heart vector movement through the QRS is associated with SCD.
Methods: A community dwelling cohort was studied. We excluded participants with paced rhythm, atrial fibrillation, prevalent CHD, heart failure, and QRS duration ≥120 ms; remaining participants (n = 13, 368, mean age 53.9±5.7ms; 56.5% female; 73.2% white) were analyzed. Baseline resting 12-lead ECG was transformed into orthogonal XYZ; filtered (40-49Hz) QRS loop length was measured. Velocity was calculated as the distance traveled by filtered heart vector over each 10ms of QRS length, divided by time.
Results: During a median follow up of 14 years, 183 participants had SCD. Averaged baseline conduction velocity (9.3±3.9 vs. 7.7±3.6 μV/ms; P=0.0001) and conduction over 110-119ms of QRS (2.6±1.3 vs. 2.1±0.9; P<0.0001) was faster in those who had SCD than those without. In unadjusted Cox regression velocity at 110-119ms (continuous variable HR 1.42; 95% CI 1.29-1.57) and velocity at 100-109ms (HR1.14; 95%CI 1.07-1.21) were associated with SCD (Figure 1). After adjustment for age, sex, CHD risk factors (total cholesterol, triglycerides, high density lipoprotein, current smoking, diabetes, body mass index, leisure activity index, systolic blood pressure, use of antihypertensive drugs), QT-prolonging drugs, ECG characteristics (heart rate, QRS duration, QTc, QRS-T angle, sex-specific Cornell product), and stratified by race and study center, 110-119ms velocity (HR 1.21; 95%CI 1.08-1.36) and 100-109ms velocity (HR 1.09; 95%CI 1.02-1.16) remained significant predictors of SCD.
Conclusions: Increased velocity of the heart vector movement through terminal 20 ms of filtered QRS loop is an independently associated with SCD in community-dwelling cohort of CHD-free adults.
Author Disclosures: L.G. Tereshchenko: None. C.A. Henrikson: None. E. Soliman: None. M. Kabir: None. S. Agarwal: None. N. Sotoodehnia: None. D.S. Siscovick: None. D. Arking: None. S. Solomon: None. W. Post: None. J. Coresh: None. M.E. Josephson: None.
- © 2014 by American Heart Association, Inc.