Feasibility of an accurate assessment of myocardial salvage by comparing functional and perfusion abnormalities in post-reperfusion gated SPECT.

BACKGROUND: Because of persistent stunning, post-treatment functional abnormalities could identify the initial risk area. The study aims to detect myocardial salvage using post-revascularization gated SPECT in acute myocardial infarction (AMI) treated by reperfusion therapy. METHODS: In 36 AMI patients, we performed a first gated SPECT injecting (99m)Tc-sestamibi before primary percutaneous coronary intervention (PCI), and a second 5 days later. The salvage index defined by the two perfusion images was compared with the value obtained by subtracting in the second gated SPECT the extent of perfusion defect from the extent of wall thickening abnormalities. RESULTS: The wall thickening salvage index correlated with the reference perfusion salvage index (Spearman's ρ = .92, P < .0001), with a 95% limit of agreement = ±.25. The agreement between the classifications in salvage index tertiles of the reference and of the wall thickening salvage index was good (kappa = .75). All patients with optimal PCI result and 18/24 of those with intermediate or poor outcome were correctly classified. CONCLUSIONS: Comparing function and perfusion in a single post-PCI (99m)Tc-sestamibi gated SPECT it is possible to estimate myocardial salvage. This could have useful implications in studies comparing different treatment strategies for AMI.