European Journal of Radiology 28 (1998) 171 – 175 Comparison of Iotrolan 320 and Iohexol 350 in cardiac angiography: a randomised double-blind clinical study N. Mezilis a, *, M.Y. Salame a , J.F. Dyet b , S.O. Arafa a , G.D.G. Oakley a , D.C. Cumberland a a Department of Cardiology, Northern General Hospital, Herries Road, Sheffield S57AU, UK b Department of Radiology, Hull Royal Infirmary, Anlaby Road, Hull HU32JZ, UK Received 2 May 1997; received in revised form 28 August 1997; accepted 29 August 1997 Abstract Objecti6e: A double-blind randomised study was conducted in two British centres, to evaluate the safety, tolerance and efficacy of the new dimeric non-ionic contrast medium Iotrolan 320 in comparison with the monomeric non-ionic compound Iohexol 350 in coronary angiography. Methods and Material: 120 patients were randomised to receive either Iotrolan at a concentration of 320 mgI/ml or Iohexol at a concentration of 350 mgI/ml, during selective coronary angiography and left ventriculography. The variables measured were: maximum increase of the left ventricular end-diastolic pressure up to 6 min after ventriculography, haemodynamic and electrocardiographic variables, arrhythmogenicity, clinical laboratory parameters, tolerance, adverse events and efficacy. Results: Iotrolan resulted in a smaller change of left ventricular end-diastolic pressure compared to Iohexol, but the difference was not statistically significant. Transient changes in left ventricular systolic pressure, intra-arterial systolic pressure, intra-arterial diastolic pressure, and in electrocardiographic parameters, occurred after the injections, but they were not clinically significant. Changes in the clinical laboratory markers from baseline values were comparable between the two groups and confirmed good renal and hepatic tolerance. During the left ventriculogram, Iotrolan resulted in less symptoms compared to Iohexol (P =0.002). Adverse events, which were mild or moderate in most cases, were observed with no statistical difference between the two agents. The contrast quality of both agents was good with no statistical difference. Conclusion: This study did not show a significant difference between Iotrolan 320 and Iohexol 350 with regard to cardiovascular safety or patient tolerance, except for a minor difference in the intensity of heat/warmth sensation. © 1998 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Contrast media; Coronary angiography; Haemodynamics; ECG; Adverse reactions 1. Introduction All iodinated X-ray contrast media currently used in cardiac angiography exhibit some degree of cardiovas- cular side effects which are related to their osmolality and ionicity. Many clinical investigations confirm that low osmolar non-ionic monomeric X-ray contrast me- dia produce less electrophysiologic and haemodynamic effects in comparison with ionic high osmolar prepara- tions [1–4]. Since the osmolality of non-ionic monomeric tri-iodinated contrast media is markedly higher than that of blood, additional improvement of cardiovascular safety could be expected by its further reduction. Iotrolan is a non-ionic, dimeric, hexa-iodi- nated compound with an iodine concentration of 320 mg/ml and osmolality of only 0.32 Osm/Kg H 2 O and thus very close to the osmolality of blood (0.29 Osm/ Kg H 2 O). The primary aim of this study was to evaluate the safety, tolerance and diagnostic efficacy of Iotrolan 320 in selective coronary angiography and left ventriculog- raphy in comparison with the commonly used contrast medium Iohexol 350. * Corresponding author. Department of Cardiology, University Hospital of Heraklion, Vouton-Stavrakia 1352, Heraklion, Crete, Greece. Tel: +30 81 392706; fax: +30 81 542055. 0720-048X/98/$ - see front matter © 1998 Elsevier Science Ireland Ltd. All rights reserved. PII S0720-048X(97)00131-9