electrocardiographic monitoring of 52 consecutive patients undergoing upper gastrointestinal endoscopy revealed that arrhythmias during the procedures were common ( 38.5 % ) and tended to occur more frequently in the elderly ( 75 % ) , in persons with heart disease ( 54.5 % ) , and in persons with chronic lung disease ( 89 % ) .
C0003811
arrhythmias
C0018799
heart disease