Importance: The role of stress cardiac magnetic resonance (CMR) imaging in clinical decision-making by reclassification of risk across American College of Cardiology/American Heart Association guideline-recommended categories has not been established. Objective: To examine the utility of stress CMR imaging for risk reclassification in patients without a history of coronary artery disease (CAD) who presented with suspected myocardial ischemia. Design, Setting, and Participants: A retrospective, multicenter cohort study with median follow-up of 5.4 years (interquartile range, 4.6-6.9) was conducted at 13 centers across 11 US states. Participants included 1698 consecutive patients aged 35 to 85 years with 2 or more coronary risk factors but no history of CAD who presented with suspected myocardial ischemia to undergo stress CMR imaging. The study was conducted from February 18, 2019, to March 1, 2020. Main Outcomes and Measures: Cardiovascular (CV) death and nonfatal myocardial infarction (MI). Major adverse CV events (MACE) including CV death, nonfatal MI, hospitalization for heart failure or unstable angina, and late, unplanned coronary artery bypass graft surgery. Results: Of the 1698 patients, 873 were men (51.4%); mean (SD) age was 62 (11) years, accounting for 67 CV death/nonfatal MIs and 190 MACE. Clinical models of pretest risk were constructed and patients were categorized using guideline-based categories of low (<1% per year), intermediate (1%-3% per year), and high (>3% year) risk. Stress CMR imaging provided risk reclassification across all baseline models. For CV death/nonfatal MI, adding stress CMR-assessed left ventricular ejection fraction, presence of ischemia, and late gadolinium enhancement to a model incorporating the validated CAD Consortium score, hypertension, smoking, and diabetes provided significant net reclassification improvement of 0.266 (95% CI, 0.091-0.441) and C statistic improvement of 0.086 (95% CI, 0.022-0.149). Stress CMR imaging reclassified 60.3% of patients in the intermediate pretest risk category (52.4% reclassified as low risk and 7.9% as high risk) with corresponding changes in the observed event rates of 0.6% per year for low posttest risk and 4.9% per year for high posttest risk. For MACE, stress CMR imaging further provided significant net reclassification improvement (0.361; 95% CI, 0.255-0.468) and C statistic improvement (0.092; 95% CI, 0.054-0.131), and reclassified 59.9% of patients in the intermediate pretest risk group (48.7% reclassified as low risk and 11.2% as high risk). Conclusions and Relevance: In this multicenter cohort of patients with no history of CAD presenting with suspected myocardial ischemia, stress CMR imaging reclassified patient risk across guideline-based risk categories, beyond clinical risk factors. The findings of this study support the value of stress CMR imaging for clinical decision-making, especially in patients at intermediate risk for CV death and nonfatal MI.
Bibliographical noteFunding Information:
reported receiving grants from Swiss National Science Foundation (SNSF grant P2LAP3_184037), Novartis Foundation for Medical-Biological Research, Bangerter-Rhyner Foundation, and SICPA Foundation during the conduct of the study. Dr Bingham reported receiving grants from the Society for Cardiovascular Magnetic Resonance (SCMR) during the conduct of the study. Dr Arai reported receiving grants and nonfinancial support from Bayer, grants and nonfinancial support from Siemens, and nonfinancial support from Circle CVI during the conduct of the study; in addition, Dr Arai had a patent to Method and System for Automatically Generating Fully Quantitative Pixel-Wise Myocardial Blood Flow and Myocardial Perfusion Reserve Maps to Detect Ischemic Heart Disease Using Cardiac Magnetic Resonance Perfusion Imaging pending; and Dr Arai is a principal investigator or coinvestigator on US Government Cooperative Research and Development Agreements with Bayer, Siemens, and Circle CVI. Dr Patel reported receiving grants from Astellas and personal fees from Astellas outside the submitted work. Dr Schulz-Menger reported receiving grants from Bayer outside the submitted work. Dr Stuber reported receiving grants from SNSF and nonfinancial support from Siemens Healthineers outside the submitted work. Dr Simonetti reported receiving grants from the SCMR during the conduct of the study and grants from Siemens outside the submitted work. Dr Murthy reported receiving speaking honoraria and research funding from General Electric, grants and personal fees from Siemens, and personal fees from Ionetix, Curium, and Jubilant Draximage
Imaging in the US Registry was funded by the SCMR, using research grant 2015A050636 jointly sponsored by Siemens Healthineers (Erlangen, Germany) and Bayer AG (Leverkusen, Germany).
© 2020 American Medical Association. All rights reserved.
PubMed: MeSH publication types
- Journal Article