Quantitative assessment of serial 'mini ECG maps', single lead ECGs, and standard precordial ECGs in patients with acute anterior Q-wave myocardial infarction: Comparisons with 49-lead precordial ECG maps

A comparison of seven ECG systems with 49-lead precordial maps, recorded from 20 patients with an acute anterior Q-wave myocardial infarction, was carried out. A total of 265 sets of ECG data recorded at predetermined time intervals form admission to discharge of the patients were utilized in the analysis. A separate analysis was focused on correlations of ECG data from individual patients. ECG variables for all ECG systems included the sums of ST-segment elevations, the number of ECG leads showing such changes, and the sums of R-waves and Q-waves from leads displaying ST-segment elevations. Also the amplitudes of ST-segment elevation, R-wave and Q-wave of the single lead with the maximal ST-segment elevation from the 49-lead map and the standard ECG recorded on admission were utilized in the analysis. A composite performance index was calculated based on the correlations of each ECG system with the corresponding 49-lead map; such index reflected correlations of St-segment elevations, number of areas showing such changes, R-waves and Q-waves. Finally a performance index with consideration of the number of leads employed by each ECG systems was calculated. It was concluded that the routinely available standard ECG provides a good reflection of electrocardiographic perturbations as depicted by precordial partial maps, and that the latter do not afford any advantages over the array of 6 precordial ECG leads in the monitoring of patients with acute anterior Q-wave myocardial infarction.