Usefulness of exercise test in selected patients coming to the emergency department for acute chest pain. por Macor, F, Cassin, M, Pitzorno, C, Dall'Armellina, E, Carniel, E, Marcianò, F, Dametto, E, Bitto, S, Martin, G, Antonini-Canterin, F, Cervesato, E, Burelli, C, Nicolosi, G