Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in patients with congestive heart failure and chronic kidney disease.

BACKGROUND: Patients with coexistent heart failure and chronic kidney disease (CKD) have a poor prognosis, possibly related to the underuse of standard medical therapies--angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARB). METHODS: We performed a retrospective analysis of the Minnesota Heart Survey, identifying patients hospitalized in 2000 in the Minneapolis-St Paul metropolitan area with heart failure. The main outcome measure was the association of ACE-I and ARB use on 30-day and 1-year mortality, stratified by glomerular filtration rate (GFR). RESULTS: Compared to patients with heart failure with preserved renal function (GFR > or = 90 mL/min), patients with severely impaired renal function (GFR <15 mL/min) were far less likely to receive ACE-I or ARB during hospitalization (52.0% vs 69.5%, P < .0001) or at discharge (50.5% vs 65.1%, P < .0001). Worsening renal function was associated with increased mortality, both at 30 days and at 1 year. The inhospital use of either an ACE-I or ARB was associated with significantly reduced 30-day mortality (OR 0.45, 95% CI 0.28-0.59) after adjusting for multiple risk factors. Similarly, the discharge prescription of either an ACE-I or ARB was associated with a significant reduction in adjusted 1-year mortality (OR 0.72, 95% CI 0.58-0.91). However, among patients on dialysis, there was no benefit of ACE-I or ARB on either 30-day or 1-year mortality. CONCLUSIONS: Angiotensin-converting enzyme inhibitors and ARB are underused in patients with heart failure with chronic kidney disease. Given the reduction in 30-day and 1-year mortality, these medications should be considered in most patients with heart failure, independent of underlying renal function. Among patients on hemodialysis, further investigation is warranted.

Iso-osmolar radio contrast iodixanol in patients with chronic kidney disease.

BACKGROUND: Although radio contrast volume has been associated with worsening post-procedural kidney function, this relationship has not been extensively studied using an iso-osmolar contrast agent in chronic kidney disease patients. METHODS: We retrospectively studied patients undergoing cardiac catheterization at the University of Minnesota from 2000 to 2004, using the iso-osmolar contrast agent, iodixanol. All patients were included who had calculated creatinine clearance (CCR) < 60 mL/min, not on dialysis, and serum creatinine measured on the same day and within 7 days after the procedure. Comparison of a subgroup with severe chronic kidney disease and diabetes mellitus was compared to a similar historical control group that used the low-osmolar contrast agent, iohexol. RESULTS: Serum creatinine and CCR were 2.9 +/- 1.5 mg/dL and 33.4 +/- 12.0 mL/min (mean +/- standard deviation), respectively, at baseline in 117 cases. Peak creatinine increased by 0.03 +/- 0.7 mg/dL after 84.3 +/- 67.3 mL of iodixanol was used. Contrast-induced nephropathy definition was fulfilled in 22 (18.8%) cases. A non-significant negative correlation was found between the volume of iodixanol and the change in creatinine (r2 = 0.0011, p = 0.7254). A subgroup with severe chronic kidney disease and diabetes mellitus with iodixanol had a significantly lower creatinine increase (n = 25, 0.09 +/- 0.5 mg/dL), compared to historical controls (n = 42, 0.7 +/- 0.8 mg/dL) with iohexol (p < 0.001). A non-significant positive correlation between volume of contrast and change in creatinine was found in this subgroup who received iodixanol (n = 25, r2 = 0.0756, p = 0.1835), but was significant in the historical controls who received iohexol (n = 42, r2 = 0.135, p = 0.017). CONCLUSIONS: The volume of iso-osmolar radio contrast does not affect the incidence of contrast-induced nephropathy in patients with chronic kidney disease. A randomized trial evaluating the incidence of contrast nephropathy would verify the safety of ad hoc versus staged angiographic procedures in this population.