Background:
Elevated uric acid level is associated with an increased risk of adverse outcome in patients with chronic heart failure (CHF). On the other hand, cardiac metaiodobenzylguanidine (MIBG) imaging provides prognostic information in patients with CHF. However, there is no information available on the prognostic value of cardiac MIBG imaging in CHF patients, relating to hyperuricemia.
Methods:
We enrolled 113 CHF outpatients (NYHA2.0±0.6, ischemic origin 48%) with radionuclide LVEF <40%(30±8%). The cardiac MIBG washout rate (WR) was calculated from the chest anterior view images obtained at 20 and 200 min after isotope injection. Abnormal WR was defined as >27% as reported previously. At the entry, we measured serum uric acid level and hyperuricemia was define as >7.0mg/dl. The primary end point was cardiac death.
Reults:
At the entry, 59 and 51 of 113 patients had abnormal WR and hyperuricemia, respectively. Serum uric acid level was significantly higher in patients with than without abnormal WR (7.3±1.8 vs 6.3±2.0 mg/dl, p=0.007). During the follow up period of 7.6±4.3 years, 35 patients had cardiac death. Cardiac death was significantly more often observed in patients with than without abnormal WR (47% vs 13%, p<0.001) and hyperuricemia (42% vs 23%, p=0.034). At multivariate Cox analysis, abnormal WR and hyperuricemia were significantly independently associated with cardiac death (p=0.02 and p=0.03, respectively). Patients with abnormal WR had a significantly greater risk of cardiac death than those with normal WR in group with hyperuricemia (p=0.004, harard ratio: 6.5, 95%CI 1.8 to 23.4) and without hyperuricemia(p=0.001, hazard ratio: 4.4, 95%CI 1.5 to 13.2).
Conclusion:
Cardiac MIBG imaging provides the additional information to hyperuricemia in CHF.
Role of comorbidities in heart failure prognosis Part 2: Chronic kidney disease, elevated serum uric acid