Risk stratification for sudden cardiac death in dilated cardiomyopathy using microvolt-level T-wave alternans.
Predicting sudden cardiac death (SCD) in patients with dilated cardiomyopathy (DCM) is difficult, so the present study evaluated the efficacy of microvolt-level T-wave alternans (TWA) and compared it with conventional parameters for prospective risk stratification of SCD in patients with DCM. Eighty-two patients with DCM (53+/-15 years old, 67M/15F) underwent assessment of TWA, left ventricular end-diastolic diameter (LVDd), left ventricular ejection fraction (LVEF), signal-averaged ECG, and analysis of 24-h Holter monitoring and QT dispersion (QTd). The endpoint of the study was defined as either SCD or documented sustained ventricular tachycardia/ventricular fibrillation (SVT/VF) during the follow-up period. During an average follow-up period of 24 months, 1 patient died suddenly and 9 patients had SVT/VF. Kaplan-Meier survival analysis showed that TWA, LVEF (< or =35%), nonsustained ventricular tachycardia, and QTd (>90ms) were significant univariate risk stratifiers (p<0.005, p<0.005, p<0.005, and p<0.05, respectively). Multivariate Cox regression analysis showed that TWA and the LVEF were statistically significant independent risk stratifiers (p<0.05 and p<0.01, respectively). A combination of TWA and LVEF identified high risk DCM patients (p<0.01); TWA for the electrical substrate and the LVEF for the hemodynamic function.
Adachi
K
K
The First Department of Internal Medicine, Kobe University School of Medicine, Japan.
Ohnishi
Y
Y
Yokoyama
M
M
D000328:Adult; D000368:Aged; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000503:physiopathology*; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests