Myocardial Metabolic Flux in Pulmonary Arterial Hypertension

Myocardial Metabolic Flux in Patients With Pulmonary Arterial Hypertension (PAH) in Response to GLP-1 Agonist Therapy: a Physiological Study Using 31-Phosphorus MR Spectroscopy

Status

Not yet recruiting

Phases

Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT07737522

Enrollment

Registered

2026-07-30

Start date

2026-10-01

Completion date

2029-04-01

Last updated

2026-07-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pulmonary Arterial Hypertension

Brief summary

The rationale for this study is that GLP-1 agonist treatment is likely to influence myocardial substrate utilisation, changing the predominant source of metabolic energy within the heart to a more energetically efficient form. This is represented by a surrogate for improved mitochondrial efficiency with reduction in myocardial lactate levels (produced by inefficient myocardial glycolysis, prevalent in the ventricles of patients with pulmonary hypertension), which can be measured by 31P-magnetic resonance spectroscopy (31P-MRS).

Interventions

DRUGGLP-1 agonist

Semaglutide

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

BASIC_SCIENCE

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to 85 Years

Healthy volunteers

Inclusion criteria

\- 1. Diagnosis of Group 1 PAH confirmed by right heart catheterisation under the National Pulmonary Hypertension Service, Royal Brompton Hospital, part of GSTT Foundation Trust 2. Age over 18, less than 85 years 3. Able to give informed consent 4. On a stable dose of PAH-specific therapies (e.g., ERA, PDE5i) for at least 3 months. 5\. Clinically justified prescription of GLP-1 agonist Semaglutide based on following criteria: BMI \> 30 or BMI \> 27 with at least one cardiovascular co-morbidity (systemic hypertension, diabetes, pre-diabetes, COPD, atrial fibrillation, dyslipidaemia, sleep disordered breathing)

Exclusion criteria

* • 1. Pregnancy * 2\. Myocardial infarction within the previous 3 months * 3\. Contraindications to MRI: Pacemakers, metallic implants, or severe claustrophobia. * 4\. Severe renal impairment: eGFR \< 15ml/min/1.73m. * 5\. Current use of SGLT2 inhibitors or GLP-1 agonist therapy (which significantly alter fuel substrate preference) or insulin therapy that cannot be held for the fasting scan

Design outcomes

Primary

Measure	Time frame
Change in the phosphocreatine-to-adenosine triphosphate (31PCr/ATP) ratio between baseline and follow up in response to treatment with GLP-1 agonist	12 weeks

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jul 31, 2026