Cardiac arrhythmias and electrocardiographic changes during upper and lower gastrointestinal endoscopy.

Ninety-two patients undergoing upper and lower gastrointestinal endoscopy were monitored with holter recording for electrocardiographic changes during the procedures. The electrocardiographic changes were seen in 20.6% of the patients. These included cardiac arrhythmias in 16.2% and ischemic ST-T changes in 4.4% of the patients. The incidence of these changes was more in patients with cardiac (36%) or pulmonary disease (25%) than in patients with no clinical cardiac or pulmonary problem (16%). The patients with baseline electrocardiographic abnormalities also showed higher incidence of such electrocardiographic changes during the endoscopic procedures when compared with patients with normal baseline electrocardiograms (32% vs. 16%).