Acetazolamide Effects on Natriuresis and Diuresis in Acute Heart Failure Treated with Furosemide and SGLT2i (SANDI)

Abstract Aims Early adjunctive therapy with intravenous acetazolamide in combination with loop diuretics has been shown to enhance decongestion in acute heart failure (AHF). However, patients receiving sodium–glucose cotransporter-2 inhibitors (SGLT2i) were excluded from previous acetazolamide trials, and the efficacy of this combination remains unknown. This study aims to evaluate the natriuretic and diuretic effects of acetazolamide in patients with AHF treated with intravenous furosemide and concomitant SGLT2i therapy. Methods The SANDI study is a prospective, multicenter, observational study enrolling 64 patients hospitalized with AHF and clinical signs of congestion. All participants will receive intravenous loop diuretics and an SGLT2i within the first 24 hours of admission. If congestion persists 24 hours after SGLT2i initiation, intravenous acetazolamide will be administered up to two consecutive days. The primary endpoint is the change in natriuresis within the first 24 hours following acetazolamide administration. Secondary endpoints include changes in diuresis, body weight, ADVOR clinical congestion score, and ultrasound-based congestion parameters. Conclusion The SANDI study will determine whether adding acetazolamide to intravenous furosemide and SGLT2i enhances early natriuresis and diuresis in patients with AHF and persistent congestion.