ESC Journals
Acetazolamide inhibits proximal tubular sodium and bicarbonate re-absorption and improved decongestive response in acute heart failure in the ADVOR trial. It is unknown whether bicarbonate levels alter the decongestive response to acetazolamide.
This is a sub-analysis of the randomized, double-blind, placebo-controlled ADVOR trial that randomized 519 patients with acute heart failure and volume overload in a 1:1 ratio to intravenous acetazolamide (500 mg/day) or matching placebo on top of standardized intravenous loop diuretics (dose equivalent of twice oral maintenance dose). The primary endpoint was complete decongestion after 3 days of treatment (morning of day 4). Impact of baseline HCO3 levels on the treatment effect of acetazolamide was assessed. : Of the 519 enrolled patients, 516 (99.4%) had a baseline HCO3 measurement. Continuous HCO3 modelling illustrated a higher proportional treatment effect for acetazolamide if baseline HCO3 ≥ 27 mmol/l. A total of 234 (45%) had a baseline HCO3 ≥ 27 mmol/l. Randomization towards acetazolamide improved decongestive response over the entire range of baseline HCO3− levels (
Acetazolamide improves decongestive response over the entire range of HCO3− levels; however, the treatment response is magnified in patients with baseline or loop diuretic-induced elevated HCO3 (marker of proximal nephron NaHCO3 retention) by specifically counteracting this component of diuretic resistance.