Assessing the myocardium after attempted reperfusion: should we bother?

In patients with AMI who have undergone attempted reperfusion, two questions need to be answered. The first, and the most obvious, is whether the myocardium has been successfully reperfused. The second, and perhaps equally important, is how much of the myocardium has been salvaged, and how much can still potentially be salvaged? To answer these questions, one must have the tools to accurately assess myocardial perfusion and infarct size. The ultimate indicator of tissue perfusion is capillary flow, whereas that of myocardial infarction is myocyte necrosis. The farther we deviate from a direct assessment of these indicators, the more imprecise we become. The Figure depicts the findings generally used in the clinical setting to determine whether reperfusion has actually occurred and the extent of myocardial salvage achieved.