[Holter electrocardiography. Analysis of 700 cases].

Seven hundred patients, 337 male (48.2%), 363 female (51.8%) requiring Holter Electrocardiogram were studied. The predominant age group ranged from 50 to 59. Symptoms were more frequent in women. Lown's classification was used to determine the frequency of arrhythmias; 47% were supraventricular arrhythmias and 56% were of ventricular origin. Most of the latter (30.9%) were included in Group I of the classification. The remaining cases appeared in a decreasing distribution in the other groups. This suggests that in our population, severe arrhythmias are infrequent. With the hypothesis that distribution of symptoms is independent from arrhythmia onset, a multiple contingency table was designed. The X2 value was 82 with freedom of 316 degrees. It confirms that 1) severe arrhythmias (ventricular tachycardia, frequent ventricular premature beats or couplets) may go unnoticed, and on the other hand 2) Symptoms are not related with occurrence or severity of arrhythmias.