The Impact of Magnesium on Exercise Tolerance, Quality of Life and Clinical Outcomes in Chronic Heart Failure Patients

Inclusion Criteria: * CHF patients NYHA II-IV \> 3 months * Diuretic therapy \> 3 months * Signed informed consent Exclusion Criteria: * chronic renal failure (serum creatinine \> 3 mg/dL) * AMI/ACS\< 3 months from randomization * Cardiac or other organ transplantation * Uncontrolled hypo/hyperthyroidism * Chronic diarrhea * Life expectancy \< 1 year * Known psychiatric disease which inhibits patient's enrollment to the study * Inability to come for follow-up visits * Any planned operation/invasive procedures in the near 6 months * Uncontrolled cardiac arrhythmias * Inability to perform 6 minute walk testing * Any participation in another interventional clinical trial \< 1 month from randomization * Any malignancy with life expectancy \< 1 year Any AV Block\> 2 degree without a pacemaker