Introduction <p>Acetazolamide is used in heart failure to improve diuresis and reduce volume overload. It acts as a diuretic in the proximal tubule, inhibiting the reabsorption of bicarbonate, water, and sodium.</p> Methods <p> A systematic review with meta-analysis of studies between 2014 and 2024 was conducted to evaluate the efficacy of Acetazolamide in decompensated heart failure compared to other drugs. Observational studies and clinical trials were considered. Searches were conducted in Medline, Scopus, Web of Science, CENTRAL and the World Health Organization clinical trials registry. A sensitivity analysis was performed for each outcome.</p> Results <p> The addition of Acetazolamide to standard diuretic treatment in patients with heart failure produces greater diuretic efficiency, a reduction in fluid balance, and a promotion of sodium loss. A decrease in Pro-BNP-NT levels and an improvement in volume overload symptoms have also been observed. The most notable result was natriuresis, where a mean difference in favour of Acetazolamide was observed: MD of 56.98 with a 95% CI (27.7–86.2).</p> Conclusions <p> Acetazolamide may be an effective option for managing congestion in patients with heart failure, improving the signs and symptoms of volume overload. Its effect on mean diuresis is comparable to or slightly higher than that observed with other diuretics. In addition, it induces favourable changes in sodium excretion, optimizing the management of electrolyte balance.</p>