Off-label use of gadolinium-based contrast agents in cardiac magnetic
resonance appeared safe regarding frequency, manifestation and severity of
acute events, according to an analysis of the EuroCMR Registry.
Among 17,767 patients who received a mean dose of 25.6 mL of
gadolinium-based contrast agent in the European
Cardiovascular Magnetic Resonance (EuroCMR) registry, 0.17% (n=30) experienced
acute adverse reactions during and immediately after the cardiac magnetic
resonance (CMR) procedure.
The reactions were considered mild, with the most frequent complaints
being rashes and hives (nine of 30), nausea (seven of 30) and anxiety (six of
30). Event rates ranged from 0.06% to 0.47%, but researchers found individual
event rates and specific characteristics of the agents showed no relation.
“The use of magnetic resonance imaging to assess the heart is a
relatively new technique and is increasingly used in the United States and
Europe,” study researcher Anja Wagner, MD, of Hahnemann University
Hospital, Drexel University College of Medicine, Philadelphia, told
Cardiology Today. “We found that the incidence of acute adverse
reactions after administration of gadolinium-based contrast was not different
from the incidence in the FDA-approved general radiology setting. Thus, the use
of gadolinium-based contrast in CMR should be regarded as safe concerning the
frequency, manifestation and severity of acute events.”
Off-label status
Currently, there are six gadolinium-based contrast agents approved by
the FDA for patients undergoing MRI, with gadobutrol (Gadavist, Bayer
Pharmaceuticals) recently approved in March. However, gadolinium-based contrast
agents for patients undergoing CMR are still off-label.
According to Wagner, “Gadolinium-based contrast agents are
frequently used in noncardiac and CMR imaging; however, the safety of
gadolinium-based contrast agents have only been studied and are FDA-approved
for noncardiac imaging. Therefore, the use of gadolinium-based contrast agents
to assess the heart is considered ‘off-label’ in Europe and the
United States.”
According to the researchers, there is a relatively low incidence of
adverse reactions vs. iodinated contrast agents used for CT, but “the
frequency, manifestation and severity of acute adverse reactions associated
with gadolinium-based contrast agents in the specific setting of CMR have not
been systematically evaluated yet.
“Despite the fact that there currently is no FDA approval of
gadolinium for
CMR in the US and many European countries, the off-label use
does not bring any additional risks for the patient,” they concluded.
“In fact, datasets such as this, when combined with efficacy studies, may
facilitate FDA approval for gadolinium in CMR in the future.”
The future with gadolinium
Natalie Bello, MD, of the department of medicine, and Warren
J. Manning, MD, of the department of radiology, both at Beth Israel
Deaconess Medical Center and Harvard Medical School, said although the EuroCMR
registry confirms the safety of using gadolinium contrast in CMR, a CMR
registry in the US and worldwide would only benefit gadolinium in CMR research.
“[A worldwide registry] would enable monitoring of indications for
CMR, use of and reaction to contrast agents, as well as adherence to
appropriateness criteria,” Bello and Manning wrote in an accompanying
editorial. “The registry may also serve as a platform for cost-effective
analyses of the down-stream testing impact of CMR.”
Wagner said the EuroCMR registry and similar registries are helpful
because they include large numbers of patients and reflect “real-world
medicine.” – by Casey Murphy
For more information:
Disclosure: One of the study researchers reports receiving
research support from Bayer-Schering. Drs. Bello and Manning report no relevant
financial disclosures.
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W. Gregory Hundley
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This study demonstrates the benefits associated with research using
registry and longitudinal follow-up data. Expanding this type of research
throughout the United States could further [help researchers] understand
suitability of gadolinium use in MRI of the CV system.
– W. Gregory Hundley, MD
Cardiology
Today Editorial Board Section Editor
Disclosure: Dr. Hundley receives contrast from
Bracco diagnostics for research purposes.