Long-Term Intermittent Administration of Levosimendan in Patients With Advanced Heart Failure

Inclusion Criteria: * Age over 18 * Severe symptoms of heart failure with dyspnea and/or fatigue at rest or minimal effort (functional class III and IV of NYHA) * Episodes of fluid retention (pulmonary or systemic venous congestion, peripheral edema) and/or low cardiac output at rest (peripheral hypoperfusion) * objective evidence of severe cardiac dysfunction determined by the presence of at least one of the following: * Left ventricular ejection fraction \</= 30% * A severe impairment of cardiac function by echocardiography with Doppler transmitral flow pattern pseudonormal or restrictive. * A left ventricular filling pressure elevated (PCP\> 16 mmHg and / or DBP average\> 12 mm Hg for pulmonary artery catheterization) * Levels of BNP or NT-proBNP higher in the absence of noncardiac causes for this. * Severe impairment of functional capacity as evidenced by one of the following: * Inability to exercise * A distance \<300 m or less in women and / or patients \>/= 75 years in the 6-minute walk test * A test of myocardial oxygen consumption \<12-14 ml / kg / min. * \>/= 1 prior history of HF hospitalization in the previous 6 months * Presence of all the above criteria despite attempts to optimize therapy including diuretics, inhibitors of the renin-angiotensin-aldosterone system and beta-blockers, unless these drugs were not tolerated or were contraindicated, and cardiac resynchronization therapy when indicated. * consent to participate in the study. Exclusion Criteria: * Levosimendan allergy or hypersensitivity. * Severe renal impairment (creatinine clearance \<30 ml / min). * Severe liver impairment. * History of autoimmune disease. * Pregnancy. * Women of childbearing age not using adequate contraception (hormonal, IUD, barrier + spermicide) * Heart disease with significant obstructions to ventricular filling or emptying. * Severe hypotension (Systolic \< 90 mmHg). * Tachycardia \> 120 bpm or a history of torsion point type ventricular tachycardia. * Severe concomitant disease with decreased short-term prognosis. * Inability to give informed consent. * Participation in another study.