Predictive value of ventricular premature beats for subsequent ischaemic heart disease in apparently healthy subjects

From 1978 to 1980, 260 healthy subjects, 40-79 years of age, underwent 24 h ambulatory electrocardiography in order to determine the prevalence and complexity of ventricular premature beats (VPBs) in adults without apparent heart disease. The number of types of VPBs seem in 5% or less were considered 'abnormal' and the present follow-up study undertaken in order to assess the significance of such 'abnormal' VPBs as predictors of subsequent ischaemic heart disease (IHD). Information concerning cardiac events within the follow-up period was available in 237 subjects. Nine were lost to follow-up and 24 refused clinical examination. IHD was documented in 13 (eight myocardial infarction, five angina pectoris). 'Abnormal' VPBs occurred in six out of 13 (46%) who later developed IHD compared to only 24 out of 213 (11%) without IHD (P less than 0.001). The presence of either more than 900 VPBs 24 h-1 or ventricular tachycardia of more than three beats, identified five out of 13 patients with IHD (sensitivity 38%), whereas 210 out of 213 with no evidence of IHD at follow-up were identified (specificity 98%). Four out of seven who initially had more than 900 VPBs 24 h-1 had IHD on follow-up. Our results have demonstrated a strong positive association between 'abnormal' VPBs observed in a random 24-h electrocardiographic recording of apparently healthy subjects 40-79 years of age and subsequent IHD. They also suggest that a 24-h ECG may be useful for the assessment of coronary risk even in asymptomatic subjects.