Abstract 11442: Prevalence and Prognostic Significance of Early Repolarisation in Patients With Idiopathic VF
Background: While some studies have argued that an early repolarisation ECG pattern in idiopathic VF patients is associated with increased risk of tachyarrhythmia, others have failed to observe this relationship. This study compared the frequency of early repolarisation patterns between idiopathic VF patients and patients receiving ICDs with an ischaemic etiology, and examined the prognostic significance of early replorisation ECG patterns.
Methods: All patients receiving a new ICD during 2008-2011 were reviewed. All idiopathic VF patients were included, and matched to randomly selected patients with ischaemic etiologies. Pre-implant ECGs were examined for the presence of J waves and elevated J points.
Results: During the study period 258 patients were implanted with new ICD systems. Of these, 26 (10%) were classified as having idiopathic VT/VF. In the idiopathic VF group 10 (39%) had J waves and a further 7 (27%) had an elevated J point, so in total 17 (65%) had evidence of an early repolarisation abnormality. In 26 patients with an ischaemic etiology, 6 (23%) had J waves and a further 10 (39%) had an elevated J point, and in total 16 (62%) had evidence of an early repolarisation abnormality. Median follow-up was 22 months, and in this time 14 (27%) patients had received appropriate therapy from their device, 5 (19%) from the idiopathic VF group and 9 (35%) from the ischaemic group. The rate of therapy was not significantly different between the two groups (hazard ratio (HR) 0.52, 95% confidence intervals (CI) 0.2-1.5), and the presence of J waves (HR 1.4, CI 0.4-4.7), or any early repolarisation (HR 1.04, CI 0.30-3.5) was not associated with an increased risk of appropriate therapy.
Conclusions: While early repolarisation abnormalities may be common in patients with idiopathic VT/VF, they are as common in ICD patients with an underlying ischaemic etiology. We did not observe early repolarisation abnormalities to be associated with an increased risk of device therapy.
- © 2012 by American Heart Association, Inc.