Recovery of Regional Left Ventricular Dysfunction After Coronary Revascularization Impact of Myocardial Viability Assessed by Nuclear Imaging and Vessel Patency at Follow-Up Angiography11This study was supported by Collaborative Research Grant 910576 from the North Atlantic Treaty Organization. It was presented in part at the 43rd Annual Scientific Session of the American College of Cardiology, Atlanta, Georgia, March 1994

Objectives. This study sought to evaluate an imaging approach using technetium-99m sestamibi scintigraphy and positron emission tomography with fluorine-18 fluorodeoxyglucose for assessment of myocardial viability proved by serial quantitative left ventricular angiography. Furthermore, the influence of successful long-term revascularization on functional recovery was studied.Background. Previous studies using positron emission tomography of myocardial perfusion and metabolism have demonstrated accurate identification of myocardial viability. However, most of these studies used a qualitative or semiquantitative wall motion analysis approach.Methods. Nuclear imaging with semiquantitative analysis of tracer uptake was performed in 193 patients with regional wall motion abnormalities. Regions were categorized as normal, viable with perfusion/metabolism mismatch, viable without mismatch (intermediate) and scar. Seventy-two of 103 patients with subsequent revascularization underwent follow-up angiography. In 52 of 72 patients, changes in regional wall motion were measured by the centerline method from serial angiography.Results. Wall motion improved in mismatch regions from −2.2 ± 1.0 to −1.1 ± 1.4 SD (p < 0.001). In contrast, regions with an intermediate pattern and those with scar did not improve. Restenosis or graft occlusion influenced functional outcome because regions with preoperative mismatch and successful long-term revascularization improved at follow-up (from −2.3 ± 1.0 to −0.8 ± 1.4 SD, p < 0.001), whereas wall motion did not change with recurrent hypoperfusion. Metabolic imaging added diagnostic information, particularly in regions with mild and moderate perfusion defects.Conclusions. This imaging approach allows detection of viability in regions with myocardial dysfunction. Wall motion benefits most in myocardium with perfusion/metabolism mismatch and successful long-term revascularization.