The study aims to assess (I) the contribution of UA itself to the CHF pathophysiology and (II) to test the effect of lowering UA by uricosuric treatment in CHF.

Hyperuricemia is often observed in patients with congestive heart failure (CHF). It has been reported that hyperuricemia is related to exercise capacity, inflammation markers and diastolic dysfunction in such patients. In addition, hyperuricemia in CHF relates to both symptomatic status (i.e. morbidity) as well as impaired prognosis (i.e. mortality). Hyperuricemia is likely to play an important role in the pathophysiology of CHF. Up-regulation of xanthine oxidase (XO) activity in CHF has been shown to contribute to higher uric acid (UA) in CHF and the therapeutic concept of XO inhibition has shown beneficial effects in a number of surrogate markers in these patients. The XO inhibition accounts for substantial decrease in oxygen radical load, the latter is discussed as the main benefit of XO inhibition treatment in hyperuricemic patients. However, whether high uric acid itself is important or merely a marker of XO activity (and hence of increased radical accumulation) is currently under discussion. Therefore, this study aims to assess (I) the contribution of UA itself to the CHF pathophysiology and (II) to test the effect of lowering UA by uricosuric treatment in CHF.

Inclusion Criteria:

• chronic heart failure
• hyperuricemia

Exclusion Criteria:

• renal dysfunction (Cr > 2.0 mg/dl)
• under treatment with anti-diabetic agents