Natriuretic response to acetazolamide predicts decongestion in acute heart failure

A robust association exists between increased natriuresis and successful decongestion with acetazolamide in patients with acute decompensated heart failure (ADHF), suggests a study.

“Acetazolamide facilitates decongestion in ADHF,” said the researchers, who analysed patients from the ADVOR* trial who had complete data on urine output and urine sodium concentration (UNa). In addition, they assessed the predictors of natriuresis and its relationship with the main endpoints.

Of the 519 patients from the ADVOR trial, 462 (89 percent) were included in the present study. For 2 days after randomization, average UNa was 92 mmol/L, while the total natriuresis was 425 mmol. Use of acetazolamide was strongly and independently associated with natriuresis, with a 16-mmol/L (19 percent) increase in UNa and 115-mmol (32 percent) greater total natriuresis.

Apart from acetazolamide, the following factors also independently predicted both a higher UNa and greater total natriuresis: higher systolic blood pressure, better renal function, higher serum sodium levels, and male sex.

Notably, a stronger natriuretic response correlated with faster and more complete relief of signs of volume overload. Such effect was already significant on the first morning of assessment (p=0.022).

The researchers likewise observed a significant interaction between the effect of allocation to acetazolamide and UNa on decongestion (p=0.007). Stronger natriuresis with better decongestion corresponded to a much shorter hospital stay (p<0.001).

After multivariable adjustments, each 10-mmol/L increase in UNa independently correlated with a lower risk of all-cause mortality or heart failure readmission (hazard ratio, 0.92, 95 percent confidence interval, 0.85‒0.99).

“UNa may be an attractive measure of effective decongestion for future trials,” the researchers said.

*Acetazolamide in Decompensated Heart Failure with Volume Overload