Practical tip: Several noninvasive methods for detection of CAD are in widespread use, including DSE, perfusion CMR, cardiac PET testing, and nuclear stress imaging. Local factors (availability, price, expertise, practice patterns) will determine the optimal strategy for imaging.

Noninvasive imaging modalities might provide critical information such as the amount and degree of ischemic or hibernating myocardium, and might be used to determine the likelihood of regional and global improvement in LV systolic function after revascularization.

Patients with HF and reduced LVEF are more likely to experience significant improvement in LVEF after successful coronary revascularization if they demonstrate:

• Reversible ischemia or a large segment of viable myocardium (> 30% of the left ventricle) in nuclear stress testing/viability study;
• Reversible ischemia or > 7% hibernating myocardium on PET scanning;
• Reversible ischemia or > 20% of the left ventricle shown as viable using DSE;
• < 50% wall thickness scarring shown by late gadolinium enhancement on CMR imaging.