Abstract
Electrocardiographic abnormalities were observed in 15 of 23 patients (65%), five with known heart disease, who were monitored for one hour prior to, during and for one hour after coloscopy. In one patient, ischemic S-T depression, 2 mm. below the resting level, persisted during the one hour following coloscopy. In all other patients, the electrocariographic abnormalities disappeared before the end of the monitoring period.