Acetazolamide to boost urine output and sodium removal in people hospitalized with acute heart failure

SANDI STUDY: Effect of Acetazolamide on Diuresis and Natriuresis in Patients With Acute Heart Failure.

This study will try adding intravenous acetazolamide for people admitted with acute heart failure who still have fluid overload despite IV furosemide and an SGLT2 inhibitor to see if it increases sodium and urine removal at 24 and 48 hours.

Quick facts

• Study type: Observational
• Enrollment: 64 (estimated)
• Sex: All
• Sponsor: Puerta de Hierro University Hospital (Academic / other)
• Locations: 1 site (Madrid)
• Trial ID: NCT06285760 on ClinicalTrials.gov

What this trial studies

SANDI is a prospective, multicenter observational study enrolling patients hospitalized for acute heart failure with clinical signs of volume overload across 11 hospitals in Spain. All patients receive guideline-directed IV loop diuretics and initiation of an SGLT2 inhibitor if not already on one; congestion is reassessed after 24 hours. Patients with persistent congestion (ADVOR score >1) receive IV acetazolamide 500 mg once daily for up to two days. The study measures natriuresis at 24 and 48 hours and records clinical course while encouraging standard dietary sodium and fluid limits.

Who should consider this trial

Good fit: Adults hospitalized with acute heart failure who have clinical signs of volume overload, elevated natriuretic peptides, and persistent congestion despite IV furosemide and SGLT2 inhibitor therapy (ADVOR score >1).

Not a fit: Patients with low blood pressure, severe renal impairment (eGFR <20 ml/min/1.73 m2) or on dialysis, type 1 diabetes, contraindications to SGLT2 inhibitors, recent acetazolamide use, or those expected to need inotropes or vasopressors are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, adding acetazolamide could help patients remove more sodium and fluid more quickly, improving congestion and potentially shortening hospital stay.

How similar studies have performed: Prior randomized work such as the ADVOR trial showed that adding acetazolamide to loop diuretics improved decongestion, and this study examines that approach in patients also treated with SGLT2 inhibitors.

Eligibility criteria

Inclusion Criteria:

* Patients admitted for acute heart failure and ≥ 1 clinical sign of volume overload (edema, ascites, or pleural effusion).
* NTproBNP levels \>1000 pg/mL or BNP \>250 ng/mL on admission.
* Under treatment with furosemide and iSGLT2 according to European guidelines and indication of association of another diuretic due to residual congestion data defined by ADVOR SCORE\>1.

Exclusion Criteria:

* Systolic blood pressure \<90 mmHg or mean arterial pressure \< 65 mmHg.
* Maintenance treatment with acetazolamide/ Treatment with acetazolamide in the month prior to inclusion in the study.
* Anticipated need for intravenous inotropes, vasopressors or nitroprusside during the study.
* Contraindication to ISGLT2.
* Type 1 diabetes mellitus
* GFR \< 20 ml/min/m2 or renal replacement therapy/ultrafiltration at any time prior to the study.
* Anticipated exposure to nephrotoxic agents, such as iodinated contrast during admission.
* Concurrent diagnosis of acute coronary syndrome.
* History of congenital heart disease requiring surgical correction.
* History of cardiac transplantation and/or ventricular assist device.
* Pregnant or breastfeeding patients.
* Inability to adequately collect diuresis.
* Serum potassium less than 3.5 mEq/L.
* Venous pH \<7.30
* Severe aortic stenosis or obstructive hypertrophic cardiomyopathy.
* Sulfonamide allergy, liver cirrhosis, renal lithiasis.

Where this trial is running

Madrid

• Julia González González — Madrid, Spain (Recruiting)

Study contacts

• Study coordinator: Julia González González

Conditions Heart Failure; Persistent Congestion; Acetazolamide