The prevalence of disturbance of cardiac rhythm in healthy New Zealand Adults: a pilot study.

Continuous portable 24-hour tape recorded monitoring of the electrocardiogram in 189 healthy adults was used to provide data about dysrhythmia during normal daily activity. The age of the subjects ranged from 20 to 70 years and the mean age was 44. One hundred and forty-eight were less than 50 years of age. Dysrhythmia, mainly asymptomatic, occurred in 71 subjects (37 percent). In 31 (16 percent) it was ventricular, in 20 (10.5 percent) it was supraventricular and in a further 20 (10.5 percent) it was combined. In 12 (6.3 percent) ventricular ectopy was considered potentially serious. It was not more prevalent in smokers. This study shows a lesser number of normal subjects with dysrhythmia than in most other reported studies.