Assessment of Renal Microcirculation With Rubidium Positron Emission Tomography (RESIST)

Assessment of Renal Microcirculation With Rubidium Positron Emission Tomography: A Proof-of-Concept Study

The aim of this study is to demonstrate that positron emission tomography imaging with Rubidium-82 (radioactive tracer) can non-invasively detect and quantify changes in renal blood flow (renal perfusion) and renal vascular resistance in both healthy subjects and patients with renal insufficiency. Ultimately, the results of this study will contribute to a better understanding of the role of positron emission imaging in the evaluation of patients with renal diseases.

Study Overview

• Status: Completed
• Conditions: Renal Microcirculation With Rubidium Positron Emission Tomography

Detailed Description

2. Hypothesis

1. We hypothesize that RBF assessed with rubidium PET is on average lower in patients with CKD. To test our hypothesis, RBF of patients with CKD and coronary artery disease (CAD) risk factors, a population characterized by renal microvascular rarefaction, will be compared to RBF of healthy controls.
2. We hypothesize that RVR assessed with rubidium PET correlates with echographic measurements of renal resistance index (RI), the current non-invasive method of choice.
3. We hypothesize that RBF quantification with rubidium PET is technically reproducible, meaning that the variation on the measurements of RBF purely attributable to technical factors (camera, positioning, tracer injection, etc.) is relatively small. To test this hypothesis, two PET scans will be acquired within a short time period.

3. Objectives and Endpoints 3.1. Primary Objective

1) To compare RBF of patients with CKD and CAD risk factors to healthy controls 3.2. Secondary Objectives

1. To compare RVR of patients with CKD and CAD risk factors to healthy controls
2. To evaluate the correlation between RVR measured with PET to renal RI as measured with echography
3. To evaluate the repeatability and reproducibility of in vivo measurements of RBF and RVR

• Study Type: Observational
• Enrollment (Actual): 30

Contacts and Locations

Study Locations

• Canada
  • Quebec
    • Montréal, Quebec, Canada, H1T 1C8
      • Montreal Heart Institute

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

1. 15 healthy volunteers
2. 15 patients with CKD and CAD risk factors with GFR between 30 and 45 mL/min/1.73m2 from HFpEF clinic at ICM

Description

Inclusion Criteria:

Control Group

1. Age ≥ 18 years and < 80 years
2. Signed informed consent
3. No medical history of renal disease

CKD Group

1. Age ≥ 18 years and < 80 years
2. Signed informed consent
3. GFR between 30 and 45 mL/min/1.73m2 measured within the last 3 months
4. At least two cardiovascular disease risk factors such as hypertension, smoking, diabetes, obesity, and dyslipidemia

Exclusion Criteria:

Control Group

1. Hypertension
2. Diabetes
3. Dyslipidemia
4. Active smoking within the last 12 month
5. Left ventricular ejection fraction <45%
6. BMI >45 kg/m2
7. Severe aortic stenosis

CKD Group

1. Left ventricular ejection fraction <45%
2. BMI >45 kg/m2
3. Severe aortic stenosis
4. Changes in medical therapy within the last 4 weeks
5. Documented renal artery stenosis
6. Known structural cause of CKD including polycystic kidney disease, obstruction, or other post-renal causes
7. Pregnancy or breastfeeding
8. Renal failure requiring dialysis within the last 90 days

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Control; 15 healthy volunteers
CKD; 15 patients with CKD and CAD risk factors with GFR between 30 and 45 mL/min/1.73m2

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Renal blood flow in units of mL/min/100g	Average difference of RBF between healthy controls and CKD participants	1 day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Renal vascular resistance in units of mmHg/mL/min/100g	Average difference of RVR between healthy controls and CKD participants	1 day
Correlation between renal vascular resistance measured with PET and measured with echography	Correlation coefficient between RBF vs echographic measurements of renal RI	Up to 4 weeks
Coefficient of repeatability of renal blood flow	Coefficient of repeatability, coefficient of variation, and correlation between repeated measurements	1 day

Collaborators and Investigators

• Sponsor: Matthieu Pelletier-Galarneau, MD MSc

Study record dates

Study Major Dates

• Study Start (Actual): July 4, 2023
• Primary Completion (Actual): November 21, 2024
• Study Completion (Actual): November 22, 2024

Study Registration Dates

• First Submitted: March 14, 2024
• First Submitted That Met QC Criteria: March 20, 2024
• First Posted (Actual): March 27, 2024

Study Record Updates

• Last Update Posted (Actual): July 29, 2025
• Last Update Submitted That Met QC Criteria: July 25, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: ICM 2023-3169

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No