Electrocardiographic changes following intravenous pyelography.

One hundred consecutive patients who underwent i.v. pyelography had ECG performed before, immediately following and 5 min after the injection. ECG changes appeared in 15 patients and were considered to be major in five of them. The incidence of ECG changes was significantly higher in patients with abnormal ECG prior to pyelography. The average age of the patients who developed changes was higher than that of patients in whom no ECG changes were observed. There was no significant difference in the incidence of ECG changes after standard and infusion pyelography.