Influence of peripheral intravenous contrast injection on the QRS complex in healthy men

Addition of Sodium to Iohexol

The addition of sodium to nonionic contrast media has reduced the incidence of arrhythmias in animal models. The influence on cardiac function and safety of sodium addition to the nonionic contrast medium iohexol (Omnipaque) was studied in a randomized, double-blind trial in patients undergoing cardioangiography. Fifty-nine patients received iohexol 350 mg I/ml with NaCl 28 mmol/l and 58, iohexol only. ECG changes after contrast injections were evaluated with continuous computerized dynamic vectorcardiography (VCG). QRS-vector difference (QRS-vd), which reflects changes in the QRS-complex, was chosen as the main parameter. Both contrast media caused changes in the QRS-complex, but there was no significant difference between the two. No serious arrhythmias were observed. Both contrast media were well tolerated. No beneficial effects from enriching iohexol with sodium were found. VCG was found to be a valuable tool in the study of contrast medium-induced ECG changes.

Expected hemoglobin decrease following percutaneous transluminal coronary angioplasty

To establish expected changes in hemoglobin during and after percutaneous transluminal coronary angioplasty (PTCA), we measured hemoglobin before, at the end of, and on the 2 mornings after PTCA in 177 consecutive patients without obvious out-of-laboratory blood loss. From these data, we calculated confidence intervals that can be used to compare group data, possibly to identify excessive blood loss with new devices or antithrombotic agents, and prediction intervals to identify unexpected blood loss in an individual patient.