Clinical trial Recruiting at 1 site Phase 1 Interventional Ages 18 and up

Understanding Diuretic Resistance in Heart Failure

Official title: Mechanisms of Diuretic Resistance in Heart Failure, Aim 3

Run by Yale University · NCT06209359 · Data updated 2026-11-12

This study is testing if adding ammonium chloride to the usual diuretic treatment can help people with heart failure who struggle to get rid of excess fluid.

Quick facts

PhasePhase 1
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment50 (estimated)
SponsorYale University
Academic / other
Locations1 site (New Haven, Connecticut)
StatusRecruiting
StartedJuly 24, 2024
Main results expectedMarch 1, 2029
Study endsMarch 1, 2029
Registry record updatedMay 22, 2026
Trial IDNCT06209359 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates are adults over 18 with a clinical diagnosis of heart failure and objective evidence of diuretic resistance.

Probably not a fit

Patients with a glomerular filtration rate below 20 ml/min or those using non-loop diuretics may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This interventional study aims to explore the mechanisms behind diuretic resistance in patients with heart failure. Participants will undergo a randomized, double-blind, placebo-controlled crossover design, starting with a diuretic response assessment using IV bumetanide. Following this, they will receive either ammonium chloride or a placebo alongside their regular diuretic treatment, with careful monitoring of their urine output and biochemical parameters. The study includes a washout period before participants switch to the alternate treatment, allowing for a comprehensive evaluation of the effects of the interventions.

Why it matters

Potential benefit: If successful, this study could lead to improved management strategies for patients with heart failure who experience diuretic resistance.

How similar studies have gone: While the specific approach of this study may be novel, similar studies have shown promise in understanding diuretic resistance in heart failure.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Clinical diagnosis of heart failure
* No plan for titration/change of heart failure medical or device therapies during the study period.
* Absence of non-elective hospitalizations in the previous 2 months.
* At optimal volume status by symptoms, exam, and dry weight.
* Serum potassium ≤ 5.0 mmol/L
* Serum sodium ≥ 130 milliequivalents/ liter (mEq/L)
* Hemoglobin ≥8 g/dL
* Age \>18 years
* Objective evidence of diuretic resistance to a 10mg bumetanide challenge (screening visit may occur under this protocol or HIC2000032328 or HIC2000034315) defined as:

  * FENa \<10% and total sodium output \<150mmol
  * And at least one of the following criteria:

    * Chronic home furosemide dose greater than or equal to 80mg furosemide equivalents
    * eGFR \< 60ml/min
    * Serum chloride \<100mmol/L
    * FENa \<5% and total sodium output \<75mmol on the 2 hour

Exclusion Criteria:

* Glomerular filtration rate (GFR) \<20 ml/min/1.73m2
* Use of any non-loop type diuretic in the last 7 days with the exclusion of low dose aldosterone antagonist (e.g., spironolactone ≤50 mg)
* History of flash pulmonary edema or a "brittle" volume sensitive HF phenotype such as amyloid cardiomyopathy
* Hemoglobin \< 8 g/dL
* Pregnant or breastfeeding
* Cirrhosis or known liver disease
* History of metabolic or respiratory acidosis within 30 days
* Use of metformin, acetazolamide, or any other agent that could predispose to acidosis
* Patients who are on metformin may be enrolled if their metformin can be safely discontinued for the randomized treatment periods in each arm. Any participants who have consistently elevated blood glucose readings \> 200 mg/dL while inpatient will not be enrolled.
* Serum bicarbonate level \<24mmol/L at screening visit
* Venous potential of hydrogen(pH) \<7.35 at screening visit
* Inability to give written informed consent or comply with study protocol or follow-up visits
* On Lithium therapy
* On pimozide or thioridazine
* Diagnosis of liver failure
* Contraindications or allergy to sulfonamides
* Any contraindication to thiazide diuretic or allergy to thiazide or bendroflumethiazide

Where it's running

  • Yale University
    New Haven, Connecticut, United States
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.