A huge number of patients undergoing evaluation for interventional implantation of aortic valve protheses suffer from severely impaired renal function. Hence, it was the aim of our study to image heart, aortic root,and aorto-iliac axis using a minimum amount of contrast agent while maintaining sufficient image quality. It has been proposed that with the use of dual-source computed tomography, the quantity of intravenous contrast agent can be reduced. On the other hand, these advanced scanners are not widespread available. We therefore optimised scanning parameters on...

34 consecutive patients with high-grade aortic valve stenosis [19 women, 15 men; age 83,1 ± 6,3 (SD) y; BMI 24,9 ± 3,3; eGFR/MDRD 56,4 ± 23,9 mL/min; 17 of 34 patients presenting with eGFR < 60mL/min/1,73 m2; adequate hydration]. Combined CTA protocol [128 slice CT scanner, collimation 128 x 0.6 mm; 60 ml Iomeprol (300 mg iodine/mL) or Iodixanol (320 mg iodine/mL); as available]: ECG-gated thoracic CTA, followed by non-gated CTA of abdominal aorta and iliac arteries. Image quality was rated semiquantitatively by consensus of...

Overall image quality was good in25 of 34patients,9 of 34showed fair quality but were sufficient for diagnostic purposes. No study or part of study were non-diagnostic. Mean attenuation values in the thoracic aorta were 302 ± 56 HU and 248 ± 72 HU in the abdominal aorta and iliac vessels. Drop in attenuation values from thoracic to abdominal aorta is caused by scan delay of 4 seconds between cardiac and abdominal part of study. Only one of 17 patients with impaired renal function (eGFR<60mL/min/1.73 m2...

In patients with impaired renal function evaluated for TAVI procedure, an optimised CT protocol using 60 mL of contrast medium allows to assess aortic root and aortoiliac vessels reliably and safely. Therefore, a decreased risk of contrast induced nephropathy (CIN) was achieved. Furthermore, the proposed protocol issuitableforother clinical settings such as vascular emergencies , e.g . aortic dissection.

Blanke Ph et al.: Combined assessment of aortic root anatomy and aortoiliac vasculature with dual-source CT as a screening tool in patients evaluated for transcatheter aortic valve implantation. AJR 2010; 195: 872-881 Bae KT: Intravenous contrast medium administration and scan timing at CT: considerations and approaches. Radiology 2010; 256: 32-61

Rainer Preuß, Jens Holzinger, Wulf-Martin Georg, Wolfgang Burchert: Radiology, Nuclear Medicine, and Molecular Imaging. Jochen Börgermann: Clinic for thoracic and cardiovascular surgery. Werner Scholtz: Clinic for cardiology All authors: Heart and Diabetes Center NRW Ruhr University Bochum Georgstraße 11 D- 32545 Bad Oeynhausen Germany