Diagnosing and Targeting Mechanisms of Diuretic Resistance in Heart Failure

August 14, 2025 updated by: Yale University

Effective diuresis is the primary goal of most acute decompensated heart failure hospitalizations, but diuretic resistance is common and our ability to detect it is limited. Further, there are therapeutically distinct groups of diuretic-resistant patients. These are not easily distinguished using currently available methods, leading to trial-and-error based treatment that promotes lengthy hospitalizations.

The aims of this study are:

  1. To develop inexpensive and efficient tools to predict diuretic response
  2. To understand the prevalence of therapeutically targetable mechanisms of diuretic resistance using endogenous lithium clearance
  3. To develop methodology to differentiate diuretic resistance mechanisms using common/inexpensive laboratory tests
  4. To provide proof of concept that mechanistically tailored diuretic therapy can improve natriuresis

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This study is a minimal-risk observational open-label single center study with randomization between two standard of care interventions. Approximately 500 patients admitted to the hospital (Yale New Haven Health System) with a clinical diagnosis of heart failure will be enrolled in the overall study.

Patients will undergo sampling of their blood and collection of urine at a minimum of 4 timepoints (called "visits"), or a minimum of 5 in the interventional arm. Patients with a low urine sodium output (<100 mmol) on Visit 1 will be eligible for 1:1 randomization to either an increased dose of their Visit 1 loop diuretic or addition of IV chlorothiazide to their Visit 1 loop diuretic.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
458

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Connecticut
      • New Haven, Connecticut, United States
        • Yale University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

For all patients:

Inclusion criteria:

  • Age ≥ 18 years
  • Clinical diagnosis of ADHF with at least one objective sign of volume overload: rales, edema, elevated JVP, preadmission weight gain
  • Current use of bolus IV loop diuretic therapy and projected need by the treating clinician for continued treatment with IV diuretics for at least 3 days with the goal of significant fluid removal (>1L net fluid loss/day)

Exclusion criteria:

  • Inability to perform informed consent or comply with the serial urine collection procedures
  • Significant bladder dysfunction or urinary incontinence
  • Hematocrit less than 21% or active bleeding

For patients in the interventional arm:

Inclusion criteria:

  • Cumulative 6-hour sodium output < 100 mmol following Visit 1 IV loop diuretic dose
  • Visit 1 IV loop diuretic dose ≤ 160 mg of furosemide equivalents
  • Serum sodium > 125 mmol/L
  • At least 6 hours since last dose of diuretic

Exclusion criteria:

  • Current use or projected future requirement by the treating physician for thiazide diuretics
  • Use of high dose mineralocorticoid receptor antagonist therapy (>50mg of spironolactone or >100mg of eplerenone) or amiloride

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Increased Intravenous Loop Diuretic (Bumetanide or Furosemide)
2.5x Visit 1 dose
Drug: Increased Intravenous Bolus Loop Diuretic Dose (Bumetanide or Furosemide)
An increase to 2.5x the Visit 1 dose of loop diuretic (bumetanide or furosemide).
Experimental: Loop Diuretic (Bumetanide or Furosemide) + IV Chlorothiazide
Loop diuretic (Bumetanide or Furosemide) dose remains the same as visit 1 dose but now with the addition of 500-1000 mg IV chlorothiazide
Drug: IV Chlorothiazide
No Intervention: Observational Arm
Subjects taking an IV loop diuretic (Bumetanide or Furosemide) that have sodium output greater than 100 mmol. These subjects will continue to be followed and have data collected on them.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Accuracy of sodium prediction equation in predicting suboptimal natriuretic response to a dose of diuretics
Time Frame: 6 hours
Suboptimal Natriuretic Response is defined as a measured sodium output of <100 mmol in the 6 hours following the dose of diuretic
6 hours
Prevalence of mechanistic sub types of Diuretic Resistance (DR) as defined by cutoff values of change in fractional excretion of lithium
Time Frame: 6 hours
Descriptions of the prevalence of the DR mechanisms at the different time points in the study will be reported.
6 hours
Accuracy of prediction of mechanistic sub types of DR using universally available laboratory tests
Time Frame: 6 hours
The relationship between the change in fractional excretion of potassium and sodium and the change in fractional excretion of endogenous lithium will be assessed in order to develop methodology to identify the etiology of DR using universally available laboratory tests.
6 hours
Change in total 6-hour sodium output between observational and randomized intervention study days, compared between intervention groups
Time Frame: 6 hours
Sodium output in response to a dose of diuretics will be measured via urine collection.
6 hours

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Prediction of mechanistic sub types of DR
Time Frame: 6 hours
Relationship between the fractional excretion of magnesium or calcium with the fractional excretion of endogenous lithium will also be assessed
6 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Yale University

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Heart, Lung, and Blood Institute (NHLBI)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jeffrey Testani, MD, Yale University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
August 31, 2015

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 23, 2020

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
January 23, 2020

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 27, 2015

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 8, 2015

First Posted (Estimated)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 11, 2015

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 17, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 14, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
August 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 1505015805
  • 1R01HL128973-01 (U.S. NIH Grant/Contract)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings