Levosimendan preconditioning in patients undergoing elective cardiac surgery with poor ejection fraction. preliminary results. Issue 1 (December 2015) - Ávalos, R; MartinezSanz, R; Jiménez, JJ; Iribarren, JL; Montoto, J; Lacruz, A; Brouard, M; Garrido, P; Prada, PC; Pérez, Jorge; García-González, M