COMBINATION OF HIGH-DOSE FUROSEMIDE AND HYDROCHLOROTHIAZIDE IN THE TREATMENT OF REFRACTORY CONGESTIVE-HEART-FAILURE

Objective We studied the synergism between high-dose furosemide and hy drochlorothiazide in patients with severe congestive heart failure and impaired renal function showing diuretic resistance to a daily dose o f furosemide of at least 250 mg. Design and setting An open study. A g eneral hospital in The Netherlands. Methods In 20 patients with severe congestive heart failure (stage III-IV according to the New York Hear t Association) with an oedematous mass of more than 5 kg and a proven diuretic resistance to high-dose furosemide, hydrochlorothiazide (25-1 00 mg daily) was added to the medication for 3-12 days, leaving the ot her medication unchanged. After correction of the hydration state, hyd rochlorothiazide was withdrawn. Variables included body weight, serum electrolytes, renal function and natriuresis. Results Addition of hydr ochlorothiazide resulted in a mean (rt standard deviation) body weight reduction of 6.7 +/- 3.3 kg per patient. Mean daily urine volume incr eased +/- from 1899 +/- 958 ml to 3065 +/- 925 ml (P<0.001). Fractiona l sodium excretion increased significantly from 3.5 +/- 3.2% to 11.5 /- 9.0% (P<0.001). The most important side effect of this combination therapy appeared to be hypokalaemia. Mean endogenous creatinine cleara nce decreased (not significantly) from 32.7 +/- 22.5 ml . min(-1). 1.7 3 m(-2) to 27.6 +/- 22.5 ml . min(-1) . 1.73 m(-2). Conclusions Additi on of hydrochlorothiazide to highdose furosemide is a powerful diureti c tool, even in patients with a significantly reduced renal function. Because of its potentially dangerous side effects (hypokalaemia), it s hould be used in a carefully controlled setting.