Anselmi M, Golia G, Marino P, Prioli MA, Rossi A, Franceschini L, Carbonieri E, Zardini P. Am J Cardiol 1994;73(8):534-8. The usefulness of transesophageal atrial pacing combined with 2-dimensional echocardiography (echo-pacing) in predicting the presence and site of jeopardized myocardium, defined as areas of myocardium perfused by a vessel with a stenosis or = 75% or by a collateral circulation if the supplying vessel was occluded, was evaluated in 31 patients with uncomplicated acute myocardial infarction who underwent coronary angiography. All 5 patients without jeopardized myocardium had a negative test, whereas 24 of 26 with jeopardized muscle had a positive test (sensitivity 92%; specificity 100%). To identify the site of jeopardized myocardium, tests that were positive for development of new asynergies were analyzed further, distinguishing those positive in the infarct or remote zone. Seven of 8 patients with new asynergies in the remote zone had areas of jeopardized myocardium outside the territory of distribution of the infarct-related vessel, whereas only 2 of 12 with new asynergies in the infarct zone had areas of jeopardized myocardium outside that territory (p 0.01), correctly predicting the site of jeopardized myocardium in 17 of 20 cases. In conclusion, echo-pacing is useful for detecting the presence and site of jeopardized myocardium after an acute myocardial infarction.