Abstract 19847: Combination of QRS Duration and JT interval is More Prognostic Than the QT interval for Cardiovascular Death in an Ambulatory Population
Background: Few studies have compared the prognostic value of the QT interval and the JT interval for cardiovascular death in an ambulatory population.
Hypothesis: We tested the null hypothesis that the prognostic value of the QT interval and the JT interval were the same for cardiovascular death in this ambulatory population.
Methods: Resting 12-lead ECGs from 20903 ambulatory subjects at the VA Health System were recorded. Rate corrected QT and JT intervals were grouped by percentiles (75th, 90th, 95th, & 99th); the use of population percentiles allows for generalizability. The primary outcome (CV death) was obtained from state and federal databases. Multivariate Cox Regressions were used to study the associations between the QT interval, JT interval, and cardiovascular death.
Results: The majority of subjects (n=18941 (91%)) were men (44 ± 8 years of age) and 9% were women 40 ± 10 years of age). Median follow-up time was 17.5 years. CVD occurred in 4% of subjects (n=884). Univariate analysis shows significant association between CVD and both QTc interval (1.6<HR<4.5, p<.0005) and JTc interval groups (1.4<HR<4.0, p<.0005). In multivariate modeling adjusting for age, sex, and QRS duration (<>120ms), the cumulative hazards ratio was highest when combining long QRS duration with a JTc interval above the >99th percentile (HR=6.9 [95%CI:4.8-9.6]p<.0005) (Figure). Similar modeling using the QTc interval was less (HR=5.7 [95%CI:4.0-8.1]p<.0005).
Adjusted HR by JTc interval percentile group.
Conclusion: We find the JTc interval to be a stronger prognostic indicator over the QTc interval for cardiovascular death in this ambulatory population.
Author Disclosures: D. Pickham: None. L. Ha: None. A. Khandelwal: None. V. Pargaonkar: None. V. Froelicher: None.
- © 2014 by American Heart Association, Inc.