Electrocardiogram changes during intrauterine injection of ionic contrast medium.

The effect of intrauterine injection of meglumine-sodium diatrizoate 60% on the electrocardiogram was studied in 28 young, healthy women during routine hysterosalpingography. The most important single finding observed was significant QTc prolongation in 25 (90%) out of the 28 women examined. QTc increased from 417 +/- 18 mseconds to 451 +/- 30 mseconds (P less than .001). This effect disappeared rapidly within 2 to 3 minutes. Saline was injected in ten women prior to contrast medium injection in order to exclude direct mechanical dilatatory effect of the injected material. The QTc did not change significantly after saline (418 +/- 18 mseconds). The mechanism involved in the QTc prolongation is not known.