Long-term prognostic significance of ambulatory electrocardiographic findings in apparently healthy subjects greater than or equal to 60 years of age.

To determine the long-term prognostic significance of frequent or complex ectopic beats and ST-segment changes on 24-hour ambulatory electrocardiogram (ECG) in apparently healthy older subjects, 98 volunteers were followed up from the Baltimore Longitudinal Study of Aging who were 60 to 85 years old and free of cardiac disease by history, physical examination and maximal treadmill testing at the time of ambulatory ECG between 1978 and 1980. Over a mean follow-up period of 10 years, coronary events developed in 14 subjects: angina pectoris in 7, nonfatal myocardial infarction in 3 and sudden cardiac death in 4. The incidence of coronary events did not differ significantly between subjects who developed the following arrhythmias and those who did not, respectively: greater than or equal to 30 supraventricular ectopic beats in any hour, 18 vs 13%; greater than or equal to 100 supraventricular ectopic beats in 24 hours, 20 vs 12%; paroxysmal atrial tachycardia, 15 vs 14%; greater than or equal to 30 ventricular ectopic complexes (VECs) in any hour, 17 vs 14%; greater than or equal to 100 VECs in 24 hours, 18 vs 14%; or repetitive VECs, 20 vs 13%. The mean 24-hour heart rate (75 +/- 8 vs 72 +/- 9 beats/min) as well as the maximal (116 +/- 20 vs 111 +/- 18 beats/min) and minimal (51 +/- 6 vs 53 +/- 7 beats/min) heart rate also did not differ between the coronary event and non-event groups.(ABSTRACT TRUNCATED AT 250 WORDS)