Routine vs Selective Cardiac Magnetic Resonance in Non-Ischemic Heart Failure

Routine vs Selective Cardiac Magnetic Resonance in Non-Ischemic Heart Failure (OUTSMART-HF) Project I-B of Imaging Modalities to Assist With Guiding Therapy and the Evaluation of Patients With Heart Failure (IMAGE-HF)

Uncovering the underlying cause of heart failure can be quite challenging and doctors often rely on imaging tests such as echo (heart ultrasound) to provide the answers. Cardiac MRI is emerging as another promising test because it gives very precise information on heart function and the amount of scarring in the muscle. Heart failure patients are increasingly being sent for cardiac MRI but the potential advantage that this test offers over others such as echo has not been fully explored.

The purpose of this study is to determine if cardiac MRI provides more information on the cause of heart failure than traditional tests such as echo. In addition, if the information provided by this test always leads to an overall improvement in a patient's heart condition over time.

This is a randomized study where subjects referred for clinically indicated heart failure workup to determine the best clinical management will undergo standard heart failure testing (including echo) OR standard testing PLUS cardiac MRI.

Primary objective: to compare the effect of routine cardiac magnetic resonance (CMR) versus standard care (i.e. echocardiography with only selective use of CMR) on the etiological diagnosis in patients with a non-ischemic heart failure (HF). The proposed categories of HF to be considered in this study include: idiopathic dilated cardiomyopathy, infiltrative cardiomyopathy, inflammatory, hypertrophic cardiomyopathy, heart failure with preserved ejection fraction (HFPEF), ischemic cardiomyopathy, mixed etiology and other (eg. pericardial, congenital, non-compaction, right ventricular failure).

Primary hypothesis: Routine use of CMR (vs. selective use) will lead to a more specific diagnostic characterization of the underlying etiology of non-ischemic heart failure. This will lead to a reduction in the diagnosis of idiopathic dilated cardiomyopathy and HFPEF.

Secondary objectives: Determine the effects that routine use of CMR in non-ischemic HF has on therapeutic decisions, on the Composite Clinical Endpoint (CCE), cardiac function, symptoms, quality of life (QoL), and costs. Ancillary measurements will include the safety of imaging tests and adverse reactions to gadolinium contrast agent.

Secondary hypothesis: Routine use of CMR will have significant impact on treatment decisions, (1) lead to more disease specific therapies and/or (2) cause a significant change in the number and class of HF meds, during follow-up. The routine CMR group will also have improved clinical outcomes (CCE), symptoms and QoL and decreased costs to the standard of care group during follow-up.

Design

Methods: Randomized controlled trial comparing i) routine CMR vs. ii) echocardiography with selective CMR in patient with HF due to NICM and/or HFPEF.

Among patients enrolled in Level I of IMAGE-HF, it is expected that 504 will have known NICM (or strongly suspected based on young age, absent risk factors and presenting history) and/or HFPEF.

Tertiary care sites (in Canada and Finland) with dedicated HF programs will participate in the study. Consecutive patients will be enrolled at sites with dedicated CMR programs (defined as minimum 200 cases/year and maximum 2 weeks waiting time in the majority of patients) and randomized to routine CMR or selective CMR. Non-ischemic HF patients from sites without dedicated CMR programs will be included in a registry of patients undergoing routine HF care (i.e. selective use of CMR). Participants in the selective CMR arm may ONLY undergo CMR for a suspicion of: 1) infiltrative myocardial disease, 2) arrhythmogenic right ventricular cardiomyopathy, 3) adult congenital heart disease or 4) pericardial disease following standard HF care including echocardiography. Other tertiary sites may be added in year 2-3 depending on recruitment needs and registry sites may become randomization sites if the experience and wait-time criteria are met.

The study population includes patients with either

1. Newly diagnosed HF within the past 12 months

   OR

2. Established HF patients with deterioration/decompensation within the past 12 months

Inclusion Criteria: Patients with new or worsening HF as above AND

1. Age > 18
2. Working clinical diagnosis (known or highly suspected) of non-ischemic cardiomyopathy (NICM) OR Clinical diagnosis of HFPEF (Signs or symptoms of heart failure with a LVEF ≥ 40%)
3. Documented history of Class II-IV NYHA HF symptoms within the past 12 months

Exclusion Criteria:

1. Prior CMR and no major change in clinical condition
2. Well-documented specific etiology (eg known amyloidosis or hemochromatosis)
3. MD considers cause of heart failure is attributable to obstructive CAD.
4. Documented previous STEMI (any territory) or NSTEMI in LAD territory
5. Severe medical conditions that significantly affect the patient's outcome (eg. active malignancy)
6. Ongoing need for advanced cardiac life support (eg IABP)
7. Severe valvular heart disease requiring surgery within the next 6 months
8. Contraindications to CMR (e.g. certain metallic implants, severe claustrophobia)
9. Contraindications to gadolinium contrast agent (GFR < 30ml/min/1,72m2, pregnancy)
10. Inability to give informed consent
11. Evidence of multivessel ischemia on stress imaging