Objectives: The aim of this study was to investigate the prognostic value of stress cardiac magnetic resonance imaging (CMR) in patients with reduced left ventricular (LV) systolic function. Background: Patients with ischemic cardiomyopathy are at risk from both myocardial ischemia and heart failure. Invasive testing is often used as the first-line investigation, and there is limited evidence as to whether stress testing can effectively provide risk stratification. Methods: In this substudy of a multicenter registry from 13 U.S. centers, patients with reduced LV ejection fraction (<50%), referred for stress CMR for suspected myocardial ischemia, were included. The primary outcome was cardiovascular death or nonfatal myocardial infarction. The secondary outcome was a composite of cardiovascular death, nonfatal myocardial infarction, hospitalization for unstable angina or congestive heart failure, and unplanned late coronary artery bypass graft surgery. Results: Among 582 patients (mean age 62 ± 12 years, 34% women), 40% had a history of congestive heart failure, and the median LV ejection fraction was 39% (interquartile range: 28% to 45%). At median follow-up of 5.0 years, 97 patients had experienced the primary outcome, and 182 patients had experienced the secondary outcome. Patients with no CMR evidence of ischemia or late gadolinium enhancement (LGE) experienced an annual primary outcome event rate of 1.1%. The presence of ischemia, LGE, or both was associated with higher event rates. In a multivariate model adjusted for clinical covariates, ischemia and LGE were independent predictors of the primary (hazard ratio [HR]: 2.63; 95% confidence interval [CI]: 1.68 to 4.14; p < 0.001; and HR: 1.86; 95% CI: 1.05 to 3.29; p = 0.03) and secondary (HR: 2.14; 95% CI: 1.55 to 2.95; p < 0.001; and HR 1.70; 95% CI: 1.16 to 2.49; p = 0.007) outcomes. The addition of ischemia and LGE led to improved model discrimination for the primary outcome (change in C statistic from 0.715 to 0.765; p = 0.02). The presence and extent of ischemia were associated with higher rates of use of downstream coronary angiography, revascularization, and cost of care spent on ischemia testing. Conclusions: Stress CMR was effective in risk-stratifying patients with reduced LV ejection fractions. (Stress CMR Perfusion Imaging in the United States [SPINS] Study; NCT03192891)
Bibliographical noteFunding Information:
The SPINS registry was funded by the Society for Cardiovascular Magnetic Resonance, using a research grant jointly sponsored by Siemens Healthineers and Bayer. These sponsors to the Society for Cardiovascular Magnetic Resonance provided financial support for the study but did not play a role in study design, data collection, analysis, interpretation, or manuscript drafting. Dr. Antiochos has received research funding from the Swiss National Science Foundation (grant P2LAP3_184037), the Novartis Foundation for Medical-Biological Research, the Bangerter-Rhyner Foundation, and the SICPA Foundation. Dr. Arai has research agreements with Siemens, Bayer, and Circle Cardiovascular Imaging. Dr. Bandettini is the principal investigator of one of the Bayer-sponsored GadaCAD2 (Gadavist-Enhanced Cardiac Magnetic Resonance Imaging to Detect Coronary Artery Disease) sites. Dr. Patel has received a research grant from and served on the Speakers Bureau of Astellas. Dr. Schulz-Menger has received research agreements with Siemens; and serves on the Advisory Board of Bayer. Dr. Stuber has received nonmonetary research support form Siemens Healthineers. Drs. Raman and Simonetti both receive institutional research support from Siemens. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- stress cardiac MRI