Abstract 11473: J Wave with Characteristic Electrocardiographic Repolarization Pattern during Acute Myocardial Infarction and Increased Risk of Development of Ventricular Fibrillation
Background: J waves with or without ST-segment elevation have been associated with increased risk of development of ventricular fibrillation (VF) in Burugada syndrome and idiopathic VF. Recently, we have described some cases showing the characteristic electrocardiographic repolarization pattern: prominent J waves with a steep downsloping ST segment, termed “ischemic J wave”, at VF events during acute myocardial infarction. Here, we tested the hypothesis that ischemic J wave is associated with VF in patients with acute myocardial infarction.
Methods and Results: This study included 252 patients pretenting with ST-segment elevation acute myocardial infarction: 1) 82 patients who developed VF and who had electrocardiography recordings within 30 minutes before or after VF during the acute phase of myocardial infarction and 2) 170 matched controls not complicated by VF. There was no difference in clinical characteristics between two groups except for lower ejection fraction in patients with VF than those without VF. Ischemic J waves (Figure) were more frequently found in patients with VF (n=54, 79.4%) than those without VF (n=16, 9.4%) (odds ratio, 18.6; 95% confidence interval, 9.4-36.8; P<0.001). In-hospital mortality was higher in patients with VF (n=14, 17.1%) than those without VF (n=6, 3.5%) (odds ratio, 5.63; 95% confidence interval, 2.2-14.8; P=0.001). During a follow-up of 2.4±1.6 years, 27 patinets died (sudden cardiac death, n=1; heart failure, n=20; non-cardiac causes, n=6). All cause mortality rate were higher in patients with VF (n=15, 18.3%) than those without VF(n=12, 7.1%) (odds ratio, 2.95; 95% confidence interval, 1.3-6.5; P=0.009).
Conclusions: Ischemic J waves were associated with increased risk of VF in patients with acute myocardial infarction. Ischemic J waves may reflect electrphysiologic abnormaliteis resulting in arrhythmogenicitc substrate for VF during acute myocardial infarction.
- © 2011 by American Heart Association, Inc.