Hemodynamics, Diuretics, and Nesiritide: A Retrospective VMAC Analysis

HYPOTHESIS: Hypotension has been proposed as the cause of nesiritide-associated increases in serum creatinine (SCr); however, this hypothesis has not been tested. METHODS: This retrospective evaluation of patients who had a pulmonary artery catheter and received nesiritide in the Vasodilation in the Management of Acute Congestive Heart Failure (VMAC) trial assessed hypotension, SCr elevation, concomitant therapy, and mortality. Patients were categorized by baseline pulmonary capillary wedge pressure (PCWP) and analyzed both for overall population and by diuretic dose. RESULTS: Compared with patients with PCWP > 23 mm Hg (n = 105), patients with PCWP < or = 23 mm Hg (n = 49) had more hypotension within 24 hours of initiating nesiritide (16% vs 7%), but neither more SCr elevation by nominal day 30 (29% vs 28%) nor higher mortality (30 days: 8.2% vs 7.7%; 6 months: 29.0% vs 29.3%). The risk of hypotension was directly related to high dose diuretics (25% vs 6%; relative risk [RR]: 4.2; 95% confidence interval [CI]: 1.10-15.82) and was not significantly increased in patients without this concomitant treatment (10% vs 7%; RR: 1.4; 95% CI: 0.34-5.93). Additionally, high dose diuretics significantly increased the risk of SCr elevation (RR: 2.6; 95% CI: 1.03-6.64) and 6 month mortality (hazard ratio: 3.6; 95% CI: 1.19-10.63) in patients with PCWP < or = 23 mm Hg. CONCLUSIONS: Hypotension is not the primary etiology for nesiritide-associated increases in SCr. High dose diuretics increase the risk of adverse outcomes in patients with PCWP < or = 23 mm Hg and should be reserved for patients in whom PCWPs are known to be markedly elevated.