Abstract 15563: Inferolateral Early Repolarization Among Non-ischemic Sudden Cardiac Death Victims
Introduction: Inferolateral early repolarization (ER) has been associated with an increased risk of sudden cardiac death (SCD) in case-control studies and also in general population. Recent studies have shown that the association of ER and SCD in general population is mainly due to increased risk of SCD due to coronary disease (CAD). The association of ER and non-ischemic SCD in a population based cohort has not been studied.
Methods: We have collected autopsy information from 4,032 SCD subjects since 1998 in the Fingesture study. Non-ischemic etiology was the cause of SCD in 951 subjects. We were able to collect pre-mortem ECGs from 275 subjects with non-ischemic SCD (mean age 57±12, male 75%). The control population consisted of general population cohort of 10,864 subjects (mean age 44 ± 8 years, male 52%).
Results: Hypertrophic cardiomyopathy related to hypertension (HTA) (25%), unexplained cardiomegaly (CMCMP) (23%), alcohol related dilated cardiomyopathy (ACMP) (24%) and idiopathic myocardial fibrosis (IMF) (15%) were the most common causes of SCD in the non-ischemic population with ECGs. A structurally normal heart was seen in only 1.5% (n=4). The prevalence of inferolateral ER was 20.7% (inferior 11.3%; lateral 13.1%; both 3.6%) among patients with non-ischemic SCD compared to 5.3% (inferior 3.3%; lateral 2.4%; both 0.4%) in the general population (p< 0.001). The ECG pattern was accompanied by a horizontal/descending ST segment in 86% of inferior ER and 100% of lateral ER. The prevalence of ER was highest in the HTA group (26%) and the ACMP group (24%). In the IMF group (20%) and the CMCMP group (13%) ER prevalence was slightly lower. The highest ER prevalence was in hypertrophic obstructive cardiomyopathy group (1/1 subjects). The history of previously diagnosed cardiac diseases was not higher among subjects with ER (55%) than those without (59%, p=0.59).
Conclusions: The prevalence of inferolateral ER among non-ischemic SCD victims is high. Almost all ER patterns are accompanied by the malignant horizontal/descending ST segment morphology. These results suggest that inferolateral ER is not only associated with an ischemic SCD but also a non-ischemic SCD.
Author Disclosures: L. Holmström: None. A. Haukilahti: None. J. Tikkanen: None. A. Aro: None. T. Kenttä: None. M. Kortelainen: None. H. Huikuri: None. J. Junttila: None.
- © 2016 by American Heart Association, Inc.