Table 1.

Selection criteria

Inclusion criteria

Elective cardiac surgery with cardiopulmonary bypass (CPB): •coronary artery bypass grafting (CABG); •aortic valve replacement; •mitral valve replacement; •mitral valve repair; •tricuspid valve repair; •combined operations (CABG and valve surgery). Phase angle < 5.5°.

Exclusion criteria

Preoperative: •previous cardiac surgery; •left ventricle ejection fraction < 40%; •use of preoperative intra-aortic balloon pump (IABP); •critical preoperative state; •pulmonary artery mean pressure > 55 mmHg; •diagnosis of infectious endocarditis; •pacemaker. Operative: •complicated intraoperative course (unplanned intervention or low cardiac output syndrome in the operating theatre: failure to wean from CPB, intraoperative insertion of IABP or infusion of two or more inotropic medications with a cumulative dose of 0.2 mcg/kg/min); •surgery time > 6 h; •unplanned intervention. Postoperative: •disturbance of dietary rules.