Article Text
Statistics from Altmetric.com
In this issue of Heart, Carrascosa et al report on the feasibility of gadolinium-enhanced coronary computed tomography angiography (CTA) (see page 1543).1 Gadolinium attenuates x-rays and appears hyperdense on CTA.2 This off-label application may be useful in patients with an allergy to iodine, or for those with thyroid disease receiving radioactive iodine treatment because iodinated contrast may interfere with the radioisotope uptake.
The authors emphasise rightly that use of gadolinium for CTA is not justified by improved safety. Patients recruited to this study had normal baseline renal function. Patients with chronic kidney disease (CKD) are at risk of contrast-induced nephropathy (CIN) if given iodinated contrast. Until recently, there has been little or no known risk with gadolinium, but since the description of nephrogenic systemic fibrosis (NSF),3 4 a rare disorder that occurs in some patients with CKD receiving gadolinium, relative risks of these contrast agents have become less clear (table 1). The safest choice for an individual patient involves weighing the risks of NSF, CIN and adverse reactions.
- In this window
- In a new window
Gadolinium and nephrogenic systemic fibrosis
With >200 million patients having received gadolinium since the early 1980s, no cases of NSF have been reported in patients with normal renal function.5 Gadolinium is eliminated mainly through the kidneys and its half-life is 1.5 h in patients with normal renal function. In patients with advanced CKD, half-life can be >30 h. Patients receiving dialysis can require more than three dialysis sessions to remove the administered dose of gadolinium.6 Gadolinium-based contrast agents are chelates containing the gadolinium cation. When chelates remain in the body for a long time, free gadolinium is released through replacement of the gadolinium cation by body zinc or copper (transmetallation).6 Free gadolinium is …
Footnotes
Linked articles 183699.
Funding This work forms part of the research themes contributing to the translational research portfolio of Barts and the London Cardiovascular Biomedical Research Unit which is supported and funded by the National Institute of Health Research.
Competing interests None.
Provenance and peer review Commissioned; not externally peer reviewed.