STICH3C Cardiac Magnetic Resonance Observational Study

Inclusion Criteria: 1. Men and women ≥ 18 years old 2. LVEF ≤ 40% (quantified by echo, single-photon emission computed tomography \[SPECT\], or CMR within 2 months of enrollment) 3. Prognostically important CAD: either multivessel CAD (triple vessel or double vessel CAD including left anterior descendant artery (LAD), significant coronary stenosis defined as ≥ 70% based on coronary angiography, fractional flow reserve (FFR) ≤ 0.80 or instantaneous wave-free ratio (iFR) ≤ 0.89) or left main disease (+/- other CAD) for which significant stenosis defined as \> 50% based on coronary angiography, intravascular ultrasound (IVUS) minimum luminal area \[MLA\] value ≤ 6.0 mm2 (\< 4.5 mm2 Asian descent), or equivalent optical coherence tomography (OCT) measurements. 4. Either planned CABG/PCI within 3 months or CABG/PCI within the last 9 months. Exclusion Criteria: 1. Concomitant valve disease or other condition (e.g., LV aneurysm) requiring surgical repair or replacement 2. Contraindication to CMR (i.e. magnetically activated materials), gadolinium, regadenoson/adenosine/dipyridamole 3. Active neoplasm and/or severe end-organ dysfunction with expected life expectancy less than 5 years. \-