Marco Rengo1, Anoeshka Dharampal2, Marisa Lubbers2, Marc Kock3, Joachim E Wildberger4, Marco Das4, André Niezen5, Fiek van Tilborg6, Marcel Kofflard7, Andrea Laghi8, Gabriel Krestin9, Koen Nieman10,11. 1. Faculty of Pharmacy and Medicine, University of Rome Sapienza, Latina, Italy. 2. Departments of Radiology and Cardiology, Erasmus University Medical Center, Rotterdam, The Netherlands. 3. Department of Radiology, Albert Schweitzer Ziekenhuis, Dordrecht, the Netherlands. 4. Department of Radiology and Nuclear Medicine, Maastricht UMC+, Maastricht, the Netherlands. 5. Department of Radiology and Nuclear medicine, Maasstad Ziekenhuis, Rotterdam, the Netherlands. 6. Department of Radiology, Elisabeth-TweeSteden Ziekenhuis, Tilburg, The Netherlands. 7. Department of Cardiology, Albert Schweitzer Ziekenhuis, Dordrecht, the Netherlands. 8. Department of Surgical and Medical Sciences and Translational Medicine, University of Rome Sapienza, Rome, Italy. 9. Department of Radiology, Erasmus University Medical Center, Rotterdam, The Netherlands. 10. Departments of Radiology and Cardiology, Erasmus University Medical Center, Rotterdam, The Netherlands. knieman@stanford.edu. 11. Stanford University School of Medicine and Cardiovascular Institute, 300 Pasteur Dr, Room H2157, Stanford, CA, 94305, USA. knieman@stanford.edu.
Abstract
OBJECTIVE: To compare the effect of contrast medium iodine concentration on contrast enhancement, heart rate, and injection pressure when injected at a constant iodine delivery rate in coronary CT angiography (CTA). METHODS:One thousand twenty-four patients scheduled for coronary CTA were prospectively randomized to receive one of four contrast media: iopromide 300 mg I/ml, iohexol 350 mg I/ml, iopromide 370 mg I/ml, or iomeprol 400 mg I/ml. Contrast media were delivered at an equivalent iodine delivery rate of 2.0 g I/s. Intracoronary attenuation was measured and compared (per vessel and per segment). Heart rate before and after contrast media injection was documented. Injection pressure was recorded (n = 403) during contrast medium injection and compared between groups. RESULTS:Intracoronary attenuation values were similar for the different contrast groups. The mean attenuation over all segments ranged between 384 HU for 350 mg I/ml and 395 HU for 400 mg I/ml (p = 0.079). Dose-length product (p = 0.8424), signal-to-noise ratio (all p > 0.05), time to peak (p = 0.324), and changes in heart rate (p = 0.974) were comparable between groups. The peak pressures differed: 197.4 psi for 300 mg I/ml (viscosity 4.6 mPa s), 229.8 psi for 350 mg I/ml (10.4 mPa s), 216.1 psi for 370 mg I/ml (9.5 mPa s), and 243.7 psi for 400 mg I/ml (12.6 mPa s) (p < 0.0001). CONCLUSION: Intravascular attenuation and changes in heart rate are independent of iodine concentration when contrast media are injected at the same iodine delivery rate. Differences in injection pressures are associated with the viscosity of the contrast media. KEY POINTS: • The contrast enhancement in coronary CT angiography is independent of the iodine concentration when contrast media are injected at body temperature (37 °C) with the same iodine delivery rate. • Iodine concentration does not influence the change in heart rate when contrast media are injected at identical iodine delivery rates. • For a fixed iodine delivery rate and contrast temperature, the viscosity of the contrast medium affects the injection pressure.
RCT Entities:
OBJECTIVE: To compare the effect of contrast medium iodine concentration on contrast enhancement, heart rate, and injection pressure when injected at a constant iodine delivery rate in coronary CT angiography (CTA). METHODS: One thousand twenty-four patients scheduled for coronary CTA were prospectively randomized to receive one of four contrast media: iopromide 300 mg I/ml, iohexol 350 mg I/ml, iopromide 370 mg I/ml, or iomeprol 400 mg I/ml. Contrast media were delivered at an equivalent iodine delivery rate of 2.0 g I/s. Intracoronary attenuation was measured and compared (per vessel and per segment). Heart rate before and after contrast media injection was documented. Injection pressure was recorded (n = 403) during contrast medium injection and compared between groups. RESULTS: Intracoronary attenuation values were similar for the different contrast groups. The mean attenuation over all segments ranged between 384 HU for 350 mg I/ml and 395 HU for 400 mg I/ml (p = 0.079). Dose-length product (p = 0.8424), signal-to-noise ratio (all p > 0.05), time to peak (p = 0.324), and changes in heart rate (p = 0.974) were comparable between groups. The peak pressures differed: 197.4 psi for 300 mg I/ml (viscosity 4.6 mPa s), 229.8 psi for 350 mg I/ml (10.4 mPa s), 216.1 psi for 370 mg I/ml (9.5 mPa s), and 243.7 psi for 400 mg I/ml (12.6 mPa s) (p < 0.0001). CONCLUSION: Intravascular attenuation and changes in heart rate are independent of iodine concentration when contrast media are injected at the same iodine delivery rate. Differences in injection pressures are associated with the viscosity of the contrast media. KEY POINTS: • The contrast enhancement in coronary CT angiography is independent of the iodine concentration when contrast media are injected at body temperature (37 °C) with the same iodine delivery rate. • Iodine concentration does not influence the change in heart rate when contrast media are injected at identical iodine delivery rates. • For a fixed iodine delivery rate and contrast temperature, the viscosity of the contrast medium affects the injection pressure.