[Computerized electrocardiography system of Porto. I -- General description and experience with its use]

After a brief review of computer assisted ECG interpretation techniques, a microcomputer-based system for off-line ECG (Frank) analysis and interpretation developed at the University of Porto is presented. The program is menu-structured and includes report correction and editing facilities. Clinical data can be stored along with the ECG in the individual patient file. More than 500 characteristics are extracted from the ECG signal by the measurement section of the program. The diagnostic section uses Boolean-tree logic. The diagnostic threshold values and interpretation statements are kept in an independent file and can be changed at any moment by the user. Taking the cardiologist using the same logic and criteria as reference standard, an evaluation of the diagnostic efficiency of the system was performed in 509 reports from pediatric and adult patients: 7% of the reports needed corrections and 113 (3.7%) out of 3070 diagnostic statements produced had to be changed. Output options include the clinical data, more or less extensive listings of the wave measurements, X, Y and Z and polar plots and the 12-lead (derived) ECG, besides the interpretation report itself.