Comparison of time domain and spectral turbulence analysis of the signal-averaged electrocardiogram for the prediction of prognosis in idiopathic dilated cardiomyopathy.

Summary Background: Despite significant advances in the treatment of heart failure, the prognosis of patients with idiopathic dilated cardiomyopathy remains poor. Although several of prognostic vaiables have been shown to be useful in risk stratification of patients with idiopathic dilated cardiomyopathy, their predictive accuracy is low and clinical usefulness uncertain. Hypothesis: This study was undertaken to assess the signalaveraged electrocardiogram (SAECG) in patients with idiopathic dilated cardiomyopathy and to compare the ability of time domain and spectral turbulence analytic techniques to predict clinical outcome. Methods: SAECG analysis was performed in 80 patients with idiopathic dilated cardiomyopathy. Nineteen patients had left bundle-branch block and eight were taking low-dose amiodarone for life-threatening arrhythmias. Conventional time domain and spectral turbulence analyses of the SAECG were perfonned using Del Mar 183 software. Results: During a follow-up of 27 f 19 months, 24 patients developed progressive heart failure, while the others remained clinically stable. Late potentials were detected in 28%