Comparative Efficacy and Safety of Acetazolamide Versus Metolazone as an Adjunct to Standard Therapy in Patients With Acute Decompensated Heart Failure

NCT07199088 | Recruiting

• 1 other identifier: 772
• Study Type: interventional
• Target: 320
• Locations: 1 country
• Sites: 1

Brief Summary

This clinical trial aims to compare the efficacy and safety of acetazolamide versus metolazone as adjunctive treatments to standard therapy in patients with acute decompensated heart failure (ADHF). ADHF is a life-threatening condition, and current treatments often involve loop diuretics to alleviate volume overload. This study will assess the added benefit of acetazolamide and metolazone in improving decongestion, reducing hospital stays, and preventing complications such as renal dysfunction or electrolyte imbalances. Participants will be randomized to receive either acetazolamide or metolazone in addition to standard diuretic therapy. The trial will evaluate primary outcomes including successful decongestion, in-hospital mortality, and length of hospital stay, with secondary outcomes focusing on renal function, electrolyte disturbances, and overall safety. The study is conducted at Bahawal Victoria Hospital, Bahawalpur, and aims to provide valuable insights into the management of ADHF, especially in the Pakistani population.

Conditions

Acute Decompensated Heart Failure; Heart Failure, Diastolic; Heart Failure, Systolic

Outcome Measures

Primary Outcomes (1)

• Successful Decongestion

  This outcome measure assesses the resolution of clinical signs and symptoms of acute decompensated heart failure (ADHF), specifically the absence of orthopnea, reduced jugular venous distention (JVD) to \<8 cm H2O, and minimal or no peripheral edema. Successful decongestion is considered when these signs are resolved within 72 hours of intervention.

  72 hours after randomization (following 3 days of treatment with the assigned adjunct therapy).

Study Arms (2)

Acetazolamide + Standard Therapy

EXPERIMENTAL

Participants in this group will receive acetazolamide (500 mg/day) as an adjunct to standard heart failure therapy, which includes intravenous loop diuretics (Furosemide 80 mg/day). This group aims to assess the efficacy and safety of acetazolamide in improving decongestion in patients with acute decompensated heart failure.

Other: Acetazolamide

Metolazone Group

ACTIVE COMPARATOR

Participants in this group will receive metolazone (5 mg/day) as an adjunct to standard heart failure therapy, including intravenous loop diuretics (Furosemide 80 mg/day). This group serves as a comparison to the acetazolamide group, evaluating the efficacy and safety of metolazone in improving decongestion in patients with acute decompensated heart failure.

Other: Metolazone

Interventions

Acetazolamide OTHER

A carbonic anhydrase inhibitor, 500 mg orally once a day as an adjunct to loop diuretics for enhancing diuresis and improving decongestion in ADHF patients.

Acetazolamide + Standard Therapy

Metolazone OTHER

A thiazide-like diuretic, 5 mg orally once a day as an adjunct to loop diuretics for enhancing diuresis and improving decongestion in ADHF patients.

Metolazone Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged 18 years or older.
• Diagnosed with Acute Decompensated Heart Failure (ADHF), with either preserved or reduced ejection fraction (EF).
• At least one clinical sign of volume overload, such as:
• Pleural effusion (confirmed by chest X-ray or ultrasound).
• Oedema or ascites (verified by abdominal ultrasonography).
• Plasma NT-proBNP level \> 1000 pg/mL or BNP level \> 250 ng/mL at screening.
• Receiving at least 40 mg of furosemide as oral maintenance therapy for at least one month prior to the study initiation.

You may not qualify if:

• Previous use of acetazolamide or metolazone prior to the study period.
• Known hypersensitivity or allergies to the study drugs (acetazolamide or metolazone) or their components.
• Patients with electrolyte disturbances, especially hypokalemia.
• End-stage renal disease requiring dialysis or GFR \< 20 mL/min/1.73 m².
• Pregnant or breastfeeding women.
• Severe hypotension (systolic blood pressure \< 90 mmHg) or other significant comorbidities like congenital cardiac illness requiring surgery.
• Patients requiring renal replacement therapy during the hospitalization.
• History of significant electrolyte imbalances or acid-base disturbances.

Sponsors & Collaborators

• University of Health Sciences Lahore: lead

Study Sites (1)

Quaid e Azam Medical College , bahawalpur

Chak Four Hundred Fifty-four, Punjab Province, Pakistan

RECRUITING

MeSH Terms

Conditions

Heart Failure, Diastolic; Heart Failure, Systolic

Interventions

Acetazolamide; Metolazone

Condition Hierarchy (Ancestors)

Heart Failure; Heart Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Thiadiazoles; Thiazoles; Sulfur Compounds; Organic Chemicals; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Sulfonamides; Amides; Sulfones; Quinazolinones; Quinazolines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Central Study Contacts

Matiullah Azmoon

CONTACT

03221639240; matiullahazmoon@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: September 21, 2025
• First Posted: September 30, 2025
• Study Start: October 11, 2025
• Primary Completion (Estimated): October 16, 2026
• Study Completion (Estimated): October 30, 2026
• Last Updated: October 3, 2025

Record last verified: 2025-09

Locations

PA (1)