Tiny ultrasound bubbles as an alternative to catheters for measuring pressures inside the heart
Intracardiac Pressures From Microbubbles Instead of a Catheter: First in Human Study and Signal Calibration
NA · King's College London · NCT07416279
This will test whether injecting tiny ultrasound bubbles can estimate heart filling pressures in people who are having a cardiac catheterisation.
Quick facts
| Phase | NA |
|---|---|
| Study type | Interventional |
| Enrollment | 10 (estimated) |
| Ages | 21 Years to 81 Years |
| Sex | All |
| Sponsor | King's College London (other) |
| Drugs / interventions | radiation |
| Locations | 1 site (London) |
| Trial ID | NCT07416279 on ClinicalTrials.gov |
What this trial studies
Researchers will record the ultrasound contrast (microbubble) signal at the same time as gold-standard catheter pressure measurements during patients' routine cardiac catheterisation. They will compare the microbubble subharmonic signal with intracardiac pressures and develop a personalised calibration to convert the signal (dB) into pressure (mmHg). All procedures occur on the same day as the standard-of-care catheterisation, with contrast given intravenously and a small amount of additional X-ray exposure to guide the catheter. No extra follow-up visits are required beyond the usual clinical care.
Who should consider this trial
Good fit: Adults who are scheduled to undergo a clinically indicated cardiac catheterisation, can give informed consent, can receive ultrasound contrast, and have good echocardiographic acoustic windows when lying flat.
Not a fit: People with known allergy to the contrast agent (SonoVue) or its components, intracardiac right-to-left shunts, severe pulmonary hypertension, uncontrolled high blood pressure, ARDS, or current use of dobutamine would be excluded and therefore would not benefit from this approach.
Why it matters
Potential benefit: If successful, this could allow clinicians to estimate intracardiac filling pressures noninvasively using contrast echocardiography, reducing reliance on invasive catheter measurements.
How similar studies have performed: Early laboratory work and small pilot human studies have suggested microbubble subharmonic signals can reflect pressure changes, but the method is not yet established in routine clinical practice.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Participant is willing and able to give informed consent to participate in the study * Patients who require a cardiac catheterisation procedure as part of their standard medical care * Good acoustic windows for echocardiography when lying flat on their back Exclusion Criteria: * Known previous allergy to SonoVue, used in ultrasound contrast scans * Known allergy to any of the components of SonoVue microbubbles, for example, sulphur hexafluoride or polyethylene glycol (PEG), also known as macrogol, which is in bowel preparations used during colonoscopy and certain laxatives * A hole in their heart that lets blood flow from the right side to the left, skipping the lungs * Very high blood pressure in the arteries of the lungs (severe pulmonary hypertension) * Uncontrolled high blood pressure (hypertension) * Adult respiratory distress syndrome (ARDS; where severe lung inflammation prevents enough oxygen from reaching the body) * Current use of the medicine dobutamine (used to treat heart failure), or have been advised not to take dobutamine * Moderate to severe heart valve disease that could affect the catheter measurements * Recent acute coronary syndrome or unstable ischaemic cardiac disease, where blood flow to the heart muscle is reduced * Pregnant or may be pregnant * Participation in a clinical trial of a medicine within the past four months, to avoid any possible interactions with SonoVue * Participating in other research that would prolong their cardiac catheterisation procedure, to ensure that the overall process does not become too tiring or burdensome
Where this trial is running
London
- King's College Hospital — London, United Kingdom (RECRUITING)
Study contacts
- Study coordinator: Amanda Nio, PhD
- Email: amanda.nio@kcl.ac.uk
- Phone: +44 (0)20 7836 5454
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions: HFpEF - Heart Failure With Preserved Ejection Fraction, Cardiac Catheterisation, Heart Disease, Ultrasound contrast agents, Intracardiac filling pressures, Microbubble subharmonic signal, Echocardiography