Influence of renal dysfunction phenotype on mortality in decompensated heart failure with preserved and mid-range ejection fraction.

BACKGROUND: Natriuretic peptides or the blood urea nitrogen to creatinine ratio (BUN/creat) can identify high- vs low-risk renal impairment (RI) in patients with heart failure and reduced ejection fraction (HF-REF). However, the situation in HF patients with preserved ejection fraction (HF-PEF) and mid-range ejection fraction (HF-MREF) remains unclear. METHODS: We evaluated patients from the Spanish National Registry of Heart Failure (RICA) that were admitted to Internal Medicine units with acute decompensated HF. Median admission values were used to define elevated NT-proBNP and BUN/creat. RESULTS: A total of 935 patients were evaluated, 743 with HF-PEF and 192 with HF-MREF). In patients with both NT-proBNP and BUN/creat below median admission values, RI was not associated with mortality (HR 1.15; 95% CI 0.7-1.87, p=0.581 in HF-PEF and HR 1.27; 95% CI 0.58-2.81, p=0.548 in HF-MREF). However, in patients with both elevated NT-proBNP and BUN/creat, those with RI had worse survival than those without RI (HR 2.01, 95% CI 1.33-3.06, p<0.001 in HF-PEF and HR 2.79, 95% CI 1.37-5.67, p=0.005 in HF-MREF). In HF-PEF even patients with RI with only 1 of the 2 parameters elevated, had a substantially higher risk of death compared to patients without RI (HR 1.53; 95% CI 1.04 to 2.26; p=0.031). CONCLUSIONS: In this clinical cohort of acute decompensated HF-PEF and HF-MREF patients, the combined use of NT-proBNP and BUN/creat stratifies patients with RI into groups with significantly different prognoses.