Sinuatrial disease in young people.

A survey at three cardiac centres disclosed nine patients under the age of 25 years with sinus node dysfunction in the absence of other forms of heart disease. All were male and seven were above the 90th centile for height. Ambulatory monitoring was performed on all the first-degree relatives of six of the patients and three families showed conducting system disturbances in the form of sinuatrial disorders or delayed atrioventricular conduction. A genetic factor may be involved in the aetiology of sinuatrial disease in young people.