Vasodilator stress, rest myocardial perfusion cardiovascular magnetic resonance (CMR), and late gadolinium enhancement (LGE) imaging were found to have high diagnostic accuracy for coronary artery disease in a pair of clinical trials, according to a study published in the Journal of the American College of Cardiology.
“These findings supported the US Food and Drug Administration approval of gadobutrol-enhanced CMR (0.1 mmol/kg) to assess myocardial perfusion and LGE in adult patients with known or suspected coronary artery disease,” noted the investigators.
The study authors sought to determine the sensitivity and specificity of gadobutrol for detecting coronary artery disease by assessing myocardial perfusion and LGE imaging. They conducted 2 international phase 3 clinical trials (Gadobutrol-enhanced CMR to detect Coronary Artery Disease, GadaCAD1; ClinicalTrials.gov Identifier: NCT01890421; n=376; mean age, 58.5 ± 12.0; 69.1% men; 73.7% White) and GadaCAD2 (ClinicalTrials.gov Identifier: NCT01890434; n=388; mean age, 58.9 ± 10.2; 61.4% men; 67.1% White). CMR included gadobutrol-enhanced first-pass vasodilator stress and rest perfusion followed by LGE imaging. Coronary artery disease was defined by quantitative coronary angiography (QCA), but computed tomography coronary angiography could exclude significant coronary artery disease.
As the design and findings for the 2 GadaCAD trials were very similar, the results were summarized as a fixed-effect meta-analysis (n=764). In this cohort, the prevalence of coronary artery disease was 27.8% as defined by QCA stenosis ≥70%. For detecting a ≥70% QCA stenosis, the sensitivity of CMR was 78.9%, specificity was 86.8%, and area under the curve was 0.871.
For multivessel coronary artery disease, the sensitivity and specificity of CMR were 87.4% and 73.0%, respectively. For the detection of 50% QCA stenosis, sensitivity of CMR was 64.6% and specificity was 86.6%. The optimal threshold for detecting coronary artery disease was a ≥67% QCA stenosis in the GadaCAD1 trial and ≥63% QCA stenosis in the GadaCAD2 trial.
Study limitations include the fact that a QCA reference to define coronary artery disease is imperfect but practical for large-scale recruitment, and that the GadaCAD trials did not test a higher dose of gadobutrol or different specific gadolinium-based contrast agents, limiting the generalizability of the results.
“Gadobutrol-enhanced CMR has high diagnostic accuracy for detecting coronary artery disease and is now FDA-approved at a dose of 0.1 mmol/kg to assess myocardial perfusion and LGE in adults with known or suspected coronary artery disease,” noted the researchers.
Prospective studies are needed to compare the sensitivity, specificity, predictive value, advantages, and limitations of gadobutrol-enhanced CMR for assessing coronary artery disease in specifically defined subpopulations, they stressed.
Disclosures: Some of the authors declared affiliations with pharmaceutical, diagnostic, and healthcare companies. Please see the original reference for a full list of disclosures.
Arai AE, Schulz-Menger J, Berman D, et al. Gadobutrol-enhanced cardiac magnetic resonance imaging for detection of coronary artery disease. J Am Coll Cardiol. 2020;76(13):1536-1547.