ABSTRACT
BACKGROUND: Limited evidence exists regarding efficacy and safety of diuretic regimens in ambulatory, congestion-refractory, chronic heart failure (CHF) patients. OBJECTIVE: To compare the potency and safety of commonly used diuretic regimens in CHF patients. METHODS: A prospective, randomized, open-label, crossover study conducted in NYHA class II-IV CHF patients, treated in an ambulatory day-care unit. Each patient received 3 different diuretic regimens: intravenous (IV) furosemide 250mg; IV furosemide 250mg plus oral metolazone 5mg; and IV furosemide 250mg plus IV acetazolamide 500mg. Treatments were administered once a week, in one of six randomized sequences. The primary endpoint was total sodium excretion, and the secondary was total urinary volume excreted, both measured for 6 hours post-treatment initiation. RESULTS: A total of 42 patients were recruited. Administration of furosemide plus metolazone resulted in the highest weight of sodium excreted, 4691 mg (95% CI: 4153-5229) compared to furosemide alone 3835 mg (95% CI: 3279-4392), P=0.015 and to furosemide plus acetazolamide 3584 mg (95% CI: 3020-4148), P=0.001. Furosemide plus metolazone resulted in 1.84 liters of urine (95% CI: 1.63-2.05), compared to 1.58 liters (95% CI: 1.37-1.8) P=0.039 collected following administration of furosemide plus acetazolamide and 1.71 liters (95% CI 1.49-1.93) following furosemide alone. The incidence of worsening renal function (WRF) was significantly higher when adding metolazone (41%) to furosemide compared to furosemide alone (17%) and to furosemide plus acetazolamide (2.6%), P<0.001. CONCLUSIONS: In ambulatory CHF patients, furosemide plus metolazone resulted in a significantly higher natriuresis compared to IV furosemide alone or furosemide plus acetazolamide.
