Log in to MyACC
Routine vs. Selective Cardiac Magnetic Resonance in Non-Ischemic Heart Failure - OUTSMART-HF
Contribution To Literature:
The OUTSMART-HF trial showed that routine CMR among patients with nonischemic HF is not superior to selective CMR for identifying specific HF etiologies.
Description:
The goal of the trial was to assess the efficacy of routine versus selective cardiac magnetic resonance (CMR) in patients with nonischemic heart failure (HF).
Study Design
All eligible patients underwent an echocardiogram. They were then randomized in a 1:1 fashion to either routine CMR (n = 248) or selective CMR for suspicion of infiltrative cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, adult congenital heart disease, or pericardial disease (n = 252).
- Total number of enrollees: 500
- Duration of follow-up: 12 months
- Median patient age: 59 years
- Percentage female: 31%
Inclusion criteria:
- Newly diagnosed HF within 12 months, or established HF and deterioration within 12 months
- Working clinical diagnosis of either nonischemic cardiomyopathy or HF with preserved ejection fraction (EF)
- New York Heart Association class II-IV symptoms within 12 months
- Age >18 years
Exclusion criteria:
- Prior CMR with no change in clinical condition
- Previous well-documented specific HF etiology
- HF attributed to obstructive coronary artery disease, prior ST-segment elevation myocardial infarction (STEMI) or non-STEMI in the left anterior descending coronary artery distribution, evidence of multivessel ischemia on stress imaging
- Ongoing need for advanced HF support
- Severe valvular heart disease requiring surgery within 6 months
- Contraindications to CMR or gadolinium
- Life-expectancy <3 months
Other salient features/characteristics:
- At baseline, specific HF etiology in routine vs. selective group: 37% in both
- Prior HF: 21%
- Mean left ventricular EF: 29%
Principal Findings:
The primary endpoint of specific HF diagnosis in routine vs. selective imaging groups was 44% vs. 50% (p = 0.22).
Secondary outcomes for routine vs. selective imaging:
- Event-free survival at 12 months: hazard ratio 0.76, 95% confidence interval 0.48–1.21 (p = 0.24)
In the selective arm, 24% underwent CMR; only a small fraction (3/61) were performed based on protocol; the others were referred for CMR based on clinical suspicion. Patients with specific HF etiologies had more clinical events at 12 months, compared with those without specific etiologies: 19% vs. 12% (p = 0.02).
Interpretation:
The results of this trial indicate that routine CMR among patients with nonischemic HF is not superior to selective CMR for identifying specific HF etiologies. However, CMR did increase diagnostic yield compared with transthoracic echocardiography alone. Although not specifically studied, a selective strategy is likely to be more cost-effective. There was a high rate of nonadherence to protocol in the selective arm, and nearly one quarter of these patients ended up getting a CMR; the vast majority were protocol violations, and based on clinical suspicion.
References:
Paterson DI, Wells G, Erthal F, et al., on behalf of the IMAGE-HF 1B Investigators. OUTSMART HF: A Randomized Controlled Trial of Routine Versus Selective Cardiac Magnetic Resonance for Patients With Non-Ischemic Heart Failure (IMAGE-HF 1B). Circulation 2020;Jan 8:[Epub ahead of print].
Clinical Topics: Arrhythmias and Clinical EP, Congenital Heart Disease and Pediatric Cardiology, Heart Failure and Cardiomyopathies, Noninvasive Imaging, Genetic Arrhythmic Conditions, SCD/Ventricular Arrhythmias, Congenital Heart Disease, CHD and Pediatrics and Arrhythmias, CHD and Pediatrics and Imaging, Acute Heart Failure, Echocardiography/Ultrasound, Magnetic Resonance Imaging
Keywords: Arrhythmogenic Right Ventricular Dysplasia, Cardiomyopathies, Diagnostic Imaging, Echocardiography, Heart Defects, Congenital, Heart Failure, Magnetic Resonance Imaging, Pericardium, Stroke Volume
< Back to Listings
