Ioana Mozos , Mircea Hancu , Corina Serban , Anca Tudor , Lelia Susan
Introduction: Late ventricular potentials (LVP), recorded using signal averaged ECG (SA-ECG), are low-amplitude, high-frequency waveforms, appearing in the terminal part of the QRS complex, and are considered predictors of ventricular arrhythmia and sudden cardiac death.
Hypothesis: SA-ECG parameters can be predicted from 12-lead ECG variables in post-infarction heart failure patients.
Methods: Thirty post infarction heart failure patients were enrolled in our study, and they underwent: 12- lead ECG and SA-ECG.
Results: Among patients with LVP, 75% had a prolonged QTmax (maximal QT interval), 85% a prolonged QTc (heart rate corrected QTmax), 55% QTm (mean QT) ≥ 400ms, 100% QRS (QRS duration) ≥ 100ms, 95% T0e (T wave duration) > 270 ms, 95% Tpe (Tpeak-Tend interval) > 120 ms, 90% Tampl (T wave amplitude) > 0.35 mV. A significant correlation was found between SA-QRS (signal averaged ECG QRS duration) and: QT parameters (p < 0.05), QRS (r = 0.78; p < 0.01), T wave variables (p < 0.01); between RMS40 (the root mean square of the terminal 40 ms of the filtered QRS) and: QTm (p = 0.049), QRS, Toe and between LAS40 (the duration of the low-amplitude signal) and: QTc, Tampl. LVP were significant associated only with QRS (p = 0.034). QRS ≥ 110 ms and T0e ≥ 270 ms are the most sensitive predictors’ of late ventricular potentials and QTm ≥ 400 ms is the most specific.
Conclusion: SA-ECG parameters and the presence of LVP can be predicted from 12-lead ECG variables in post-infarction heart failure patients.
