Preoperative risk assessment in heart failure patients: The value of myocardial viability estimation by dobutamine echocardiography - Karagiannis, S.; Feringa, HHH; Vandomburg, R; Schouten, O; Bax, JJ; Karatasakis, G; Athanassopoulos, G; Cokkinos, D.V.; Poldermans, D (EUROPEAN HEART JOURNAL, 2007)