Author + information
- Received February 9, 1994
- Revision received May 12, 1994
- Accepted June 30, 1994
- Published online November 15, 1994.
- Gioia Turitto, MD∗,
- Ratan K. Ahuja, MD,
- Edward B. Caref, MA and
- Nabil El-Sherif, MD, FACC
- ↵∗Address for correspondence: Dr. Gioia Turitto, State University of New York Health Science Center at Brooklyn, 450 Clarkson Avenue, Box 1199, Brooklyn, New York 11203.
Objectives. This study investigated prediction of arrhythmic events by the signal-averaged electrocardiogram (ECG) and programmed stimulation in patients with nonischemic dilated cardiomyopathy.
Background. Risk stratification in patients with nonischemic dilated cardiomyopathy remains controversial.
Methods. Eighty patients with nonischemic dilated cardiomyopathy and spontaneous nonsustained ventricular tachycardia underwent signal-averaged electrocardiography (both time-domain and spectral turbulence analysis) and programmed stimulation. All patients were followed up for a mean of 22 ± 26 months.
Results. Sustained monomorphic ventricular tachycardia was induced in 10 patients (13%), who all received amiodarone. The remaining 70 patients were followed up without antiarrhythmic therapy. Of the 80 patients, 15% had abnormal findings on the time-domain signal-averaged ECG, and 39% had abnormal findings on spectral turbulence analysis. Time-domain signal-averaged electrocardiography had a better predictive accuracy for induced ventricular tachycardia than spectral turbulence analysis (88% vs. 66%, p < 0.01). During follow-up, there were 9 arrhythmic events (5 sudden deaths, 4 spontaneous ventricular tachycardia/fibrillation) and 10 nonsudden cardiac deaths. Cox regression analysis showed that no variables predicted arrhythmic events or total cardiac deaths. The 2-year actuarial survival free of arrhythmic events was similar in patients with or without abnormal findings on the signal-averaged ECG or induced ventricular tachycardia.
Conclusions. In patients with nonischemic dilated cardiomyopathy, 1) there is a strong correlation between abnormal findings on the time-domain signal-averaged ECG and induced ventricular tachycardia, but both findings are uncommon; and 2) normal findings on the signal-averaged ECG, as well as failure to induce ventricular tachycardia, do not imply a benign outcome.
☆ This study was presented in part at the 66th Scientific Sessions of the American Heart Association, Atlanta, Georgia, November 1993.
- Received February 9, 1994.
- Revision received May 12, 1994.
- Accepted June 30, 1994.