[Analysis of the electrical activity of the heart and computerization: digital criteria of right bundle-branch block].

The analysis of the electrical activity of the heart has benefitted over the last few years from the development and increased use of computer techniques. It lend itself well to these methods as the data is easily digitalised. The aim of this study was to determine digital criteria of right bundle branch block (RBBB) to facilitate diagnosis mainly when associated with right ventricular hypertrophy and true posterior myocardial infarction. Thirty-two patients (9 women and 23 men) whose electrocardiogram met the conventional criteria of the Wilson type of RBBB were chosen. Their ages ranged from 48 to 84 years (mean: 69 years); all underwent a computerised vectorcardiogram. Frank's X, Y and Z leads were treated by our computer programme. A detailed orthogonal study of the QRS and T wave loops was performed. The following parameters were determined: vectors of special interest (maximal orthogonal vector, maximal vector of the maximal vectors, half-surface vectors); the orthogonal and total surface of the QRS loop; the linear spatial speed.(ABSTRACT TRUNCATED AT 250 WORDS)