Alberto Esteban-Fernández1, Manuel Anguita-Sánchez2, Juan Luis Bonilla-Palomas3, María Anguita-Gámez4, María García5, José Luis Bernal5,6, Náyade del Prado5, Cristina Fernández Pérez5,7, Julián Pérez-Villacastin4, Juan José Gómez Doblas8, Francisco Javier Elola5. Characteristics and in-hospital mortality of elderly patients with heart failure in Spanish hospitals.