Abstract 14931: Early Repolarization Defined as J-Point Elevation and Mortality in African Americans: Insights From the Jackson Heart Study
Introduction: Conflicting data exist regarding the association of early repolarization (ER) on electrocardiogram (ECG) and clinical outcomes in African Americans (AA). ST-segment elevation manifested as J-point elevation (JPE), the junction at the end of the QRS complex and beginning of the ST segment, is one of the key features of ER. We examined the association between JPE, as surrogate marker for ER and all-cause mortality in AA in the Jackson Heart Study (JHS).
Hypothesis: ER defined as JPE ≥ 0.1 mV in any lead is associated with increased all-cause mortality in AA.
Methods: We included JHS participants with ECGs obtained at the baseline visit coding JPE and excluded patients with paced rhythms or QRS duration ≥120 ms. JPE was automatically measured from digitally recorded ECGs at study baseline. We compared the cumulative incidence of 10-year all-cause mortality and 8-year heart failure (HF) hospitalization by presence of ER in any ECG lead at baseline using Kaplan-Meier estimates and multivariable Cox models.
Results: Of the 4978 participants, 1410 (28%) had ER at baseline: anterior leads 1,379 (97.8%), lateral leads 117 (8.3%), and inferior leads 41 (2.9%). Compared with patients without JPE, those with JPE were younger, more likely to be male and current smokers, and less likely to have hypertension. There were no significant differences in the cumulative incidence or multivariable-adjusted hazards of all-cause mortality or HF hospitalization between participants with or without ER in any lead (Table). Of 2523 participants who completed exam 3 and did not have baseline ER, 246 (10%) developed JPE over a median follow-up of 8 years.
Conclusions: ER on baseline ECG was not associated with mortality or HF hospitalization in a large prospective AA community cohort. Our results suggest that ER as defined by JPE ≥ 0.1 mV may represent a benign ECG finding in AA. Future studies are needed to better characterize differences in ER between AA and Caucasians.
Author Disclosures: J.P. Kelly: Research Grant; Significant; Dr. Kelly is supported by grant 5T32 HL 7101-39 from the National Institute of Health.. M.A. Greiner: None. E.Z. Soliman: None. T.C. Randolph: None. K.L. Thomas: Other Research Support; Significant; Boston Scientific. Consultant/Advisory Board; Modest; Pfizer and Bristol Myers Squib. S.M. Dunlay: None. L.H. Curtis: Other Research Support; Modest; Boston Scientific, GlaxoSmithKline, Gilead, NCQA, and Novartis. E.C. O’Brien: Other Research Support; Modest; NIH, PCORI, Bristol-Myers Squibb, GlaxoSmithKline, Janssen Scientific, and Boehringer-Ingelheim. Consultant/Advisory Board; Modest; Portola Pharmaceuticals. R.J. Mentz: Other Research Support; Modest; Amgen, AstraZeneca, Bristol-Myers Squibb, GlaxoSmithKline, Gilead, Novartis, Otsuka, and ResMed. Honoraria; Modest; HeartWare, Janssen, Luitpold Pharmaceuticals, Novartis, ResMed, and Thoratec. Consultant/Advisory Board; Modest; Luitpold Pharmaceuticals.
- © 2016 by American Heart Association, Inc.