Association Between Temporal Changes in Early Repolarization Pattern With Long-Term Cardiovascular Outcome: A Population-Based Cohort Study.

Background The prognostic value of early repolarization pattern (ERP) remains controversial. We aim to test the hypothesis that temporal changes in ERP are associated with increased risks for sudden cardiac death (SCD) and cardiovascular death. Methods and Results A total of 14 679 middle-aged participants from the prospective, population-based cohort were included in this analysis, with ERP status recorded at baseline and during 3 follow-up visits in the ARIC (Atherosclerosis Risk in Communities) study. We related baseline ERP, time-varying ERP, and temporal changes in ERP to cardiovascular outcomes. Cox models were used to estimate the hazard ratios (HRs) adjusted for possible confounding factors. With a median follow-up of 22.5 years, there were 5033 deaths, 1239 cardiovascular deaths, and 571 SCDs. Time-varying ERP was associated with increased risks of SCD (HR, 1.59 [95% CI, 1.25-2.02]), cardiovascular death (HR, 1.70 [95% CI, 1.44-2.00]), and death from any cause (HR, 1.16 [95% CI, 1.05-1.27]). Baseline ERP was also associated with 3 outcomes. Compared with those with consistently normal ECG findings, subjects with new-onset ERP or consistent ERP experienced increased risks of developing SCD and cardiovascular death. The time-varying ERP in women, White subjects, and anterior leads and J-wave amplitudes ≥0.2 mV appeared to indicate poorer cardiovascular outcomes. Conclusions Our findings suggest that baseline ERP, time-varying ERP, new-onset ERP, and consistent ERP were independent predictors of SCD and cardiovascular death in the middle-aged biracial population. Repeated measurements of the ERP might improve its use as a risk indicator for SCD.

Association between resting painless ST-segment depression with sudden cardiac death in middle-aged population: A prospective cohort study.

BACKGOUND: Silent electrocardiographic ST change predicts future coronary heart disease (CHD) incidence and mortality, but the prognostic significance of painless ST-segment depression (STD) with respect to sudden cardiac death (SCD) in subjects without apparent CHD remain unclear. This study sought to test the association between non-ischemic resting STD and risk of SCD in the general population. METHODS: A total of 14,935 middle-aged subjects from the prospective, population-based Atherosclerosis Risk in Communities (ARIC) study were included in this analysis. Cox models were used to estimate the hazard ratios (HRs) adjusted for possible confounding factors. STD was defined as ST-segment depression of ≥0.05 mV in two or more contiguous leads. RESULTS: A total of 626 sudden cardiac death occurred during the mean follow-up of 20.4 years. Compared with those without STD, subjects with resting painless STD of at least 0.05 mV had a significantly increased risk of developing SCD (adjusted HR, 1.45; 95% CI, 1.20 to 1.76), and those with STD ≥ 0.1 mV had even higher risk of SCD (adjusted HR, 1.90; 95% CI, 1.25 to 2.88). Significant interactions were present between gender and STD (P = .03), and between race and STD (P = .01). STD was significantly predictive of SCD in males (adjusted HR, 1.57; 95% CI, 1.22-2.01) and in whites (adjusted HR, 1.65; 95% CI, 1.27-2.14). STD in lateral leads and global leads were strong predictors of SCD. CONCLUSIONS: Resting painless STD was an independent predictor of SCD in the middle-aged population without previously diagnosed CHD.