T-wave variability as a risk stratifier in patients with dilated cardiomyopathy.
BACKGROUND
T-wave alternans is an important identifier of patients at risk of sudden cardiac death (SCD), but the procedure usually requires stress testing. In this study, the variability of T-wave amplitude (TVAR) was evaluated at rest, as a risk stratifier for SCD.


METHODS
This study included 57 patients in sinus rhythm and with a left ventricular ejection fraction < or =40%, of whom 34 (60%) received an implantable cardioverter-defibrillator (ICD) after surviving SCD, and 23 (40%) presented with ischemic or nonischemic cardiomyopathy and no history of SCD. A 20-minute high-resolution electrocardiographic recording for TVAR assessment was performed during supine rest. The vector magnitude was used as a primary lead for TVAR analysis.


RESULTS
The mean, median, and maximum (max) values of TVAR were measured. The patients with ICD had a lower max TVAR than the patients without ICD (67 vs 95 muV; P = 0.045), though the mean and median TVAR values were similar. By multivariate logistic analysis, max TVAR remained a predictor of SCD, after adjustments for potentially confounding factors (P = 0.044).


CONCLUSIONS
Max TVAR was a predictor of arrhythmic events in patients with dilated cardiomyopathy at rest.
Tasic
Jerneja
J
Department of Cardiology, University Clinical Centre Ljubljana, Ljubljana, Slovenia. jernejatasic@gmail.com
Zupan
Igor
I
D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology*; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000175:diagnosis* / Q000517:prevention & control; D017147:Defibrillators, Implantable; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors