Intravascular ultrasound (IVUS): a Cath Lab 101 guide
Reviewed by Rodnie Oro, cath lab charge nurse · Last reviewed: October 2026 · Education only, not medical advice
IVUS in one minute
What it is: a tiny ultrasound probe on a catheter passed into a heart artery to show the vessel wall and plaque in cross-section.
Who it is for: people having an angiogram or PCI where the team needs more detail, for example to size a stent, check it has expanded, or assess an unclear narrowing.
Main risks: the risks of the angiogram or PCI, plus rare artery spasm or injury.
Usually: a few extra minutes during an angiogram or PCI.
On this page: What is IVUS? · Who is it for? · When is it done? · Step by step · Recovery · Risks · Kit list · First time in the lab? · FAQ
What is IVUS?
An angiogram shows the inside outline of an artery. IVUS shows the wall itself.
- a thin catheter with an ultrasound probe is passed over the guidewire
- it is pulled back slowly, recording cross-section pictures
- the team measures the artery size, the plaque and any calcium
After stenting, IVUS checks the stent is fully expanded and well positioned.
New to the acronyms? See the Cath Lab Abbreviations A–Z.
Who is it for?
It may be considered for people with:
- sizing and planning a stent
- checking stent expansion
- unclear narrowings, including the left main artery
- understanding why a stent has failed
The decision is made by your heart team, who will talk through the reasons, the alternatives and the risks with you.
When is it done?
It can be planned in advance or done urgently. Before it, you usually have:
- blood tests, including kidney function and blood count
- an ECG, and often an echo or other scan
- a review of your medicines, especially blood thinners and diabetes medicines, as per centre protocol
- a chance to ask questions and give consent
Step by step
1. Getting ready
You lie on the X-ray table. The wrist (or groin) is numbed with local anaesthetic. ECG, blood pressure and oxygen levels are monitored. You may be given medicines to thin the blood, as per centre protocol.
2. Access
A sheath is placed in the radial artery at the wrist or the femoral artery in the groin, sizes per device and operator. A guide catheter is placed at the opening of the coronary artery and heparin is given, dose as per centre protocol. A thin guidewire is passed across the narrowing.
3. Imaging run
- A. Wire. A guidewire is placed in the artery.
- B. Catheter. The IVUS catheter is advanced beyond the area.
- C. Pull-back. It is pulled back slowly, recording images.
- D. Measure. The team measures and plans.
Most people don't feel the imaging or measurement.
4. Finishing
A final angiogram checks the result. The sheath is removed and the wrist closed with a pressure band, or the groin with pressure or a closure device, per device and operator.
Recovery and aftercare
- After the procedure: recovery depends on the main procedure (usually an angiogram or PCI).
- Going home: often the same day.
- Results: the images are stored and used to guide treatment.
- Medicines: take your blood thinners exactly as prescribed; don't stop them without talking to your heart team.
- Activity: avoid heavy lifting with the treated arm or leg for a few days.
Call 999 if you have chest pain, breathlessness, fainting, signs of a stroke, or heavy bleeding or swelling at the access site.
Risks and complications
Your team will explain the risks that apply to you. Possible problems include:
- the risks of the angiogram or PCI it is part of
- artery spasm, usually relieved with medicines
- artery tear or blockage (rare)
- rhythm disturbances (rare)
Cath lab kit list (printable)
Barts example kit list
An example from one UK centre, written generically. Every lab has its own protocol, and sizes and doses vary.
- radial or femoral arterial sheath, size per device and operator
- guide catheter, shape per operator
- coronary guidewire, per operator
- Y-connector and flush set
- heparin, as per centre protocol
- IVUS catheter and console, per device and operator
- nitrate, as per centre protocol
Procedural steps (Barts example)
- Wire in the artery; nitrate
- IVUS catheter beyond target
- Automated pull-back
- Measurements
- Treatment decision
First time in the cath lab?
đź’ˇ First-time tip
- Nitrate first. Reduces spasm.
- Flush. Prepare the catheter as per device.
- Mark landmarks. Note branches.
- Save runs. Label each run.
FAQ
Does IVUS use X-ray?
No; it uses sound.
Does it use more dye?
No.
Will I feel it?
Usually not.
Related Cath Lab 101 guides
- PCI (coronary angioplasty and stents)
- Coronary angiogram
- Chronic total occlusion (CTO PCI)
- Cath Lab Abbreviations A–Z
Sources
All checked on 10 October 2026. Each page's own date is shown where it gives one.
- Knuuti J, et al. 2019 ESC Guidelines for the diagnosis and management of chronic coronary syndromes. Eur Heart J 2020;41(3):407–477. PubMed 31504439
- Byrne RA, et al. 2023 ESC Guidelines for the management of acute coronary syndromes. Eur Heart J 2023;44(38):3720–3826. PubMed 37622654
- StatPearls (NCBI Bookshelf), search: intravascular ultrasound. ncbi.nlm.nih.gov/books
Disclaimer
Education only. This page is for general education for healthcare students, cath lab staff and curious readers. It isn't medical advice and doesn't replace advice from your own doctor, heart team or local unit protocols. Equipment and medicines are described generically. No product or manufacturer is recommended. If you think someone is having a heart emergency, call 999.
Disclosure: I work for a company that makes a device used in this procedure. This page is independent education, isn't sponsored or reviewed by any company, and doesn't recommend any product.
All diagrams on this page are original illustrations created for rodnieoro.com.
