Clinical value of the electrocardiogram in ambulatory care.

The direct impact of the electrocardiogram (ECG) on clinical outcome in an ambulatory health care population during a six-month period was reviewed. Three hundred seventy-six ECG tracings were recorded, of which 262 (69.7 percent) were interpreted as normal. The ECG was clinically useful and had direct impact on treatment in only two instances (0.5 percent of all tracings recorded). Three patients were inappropriately referred or treated because of an incorrect ECG interpretation. No electrocardiograms done on asymptomatic persons led to useful medical interventions.