Intravascular Ultrasound (IVUS)

Introduction

Intravascular ultrasound (IVUS) is an advanced imaging technique used in cardiology to visualize blood vessels from the inside. It provides detailed, high-resolution images of the arteries, which helps cardiologists assess the severity of atherosclerosis, plaque composition, and stent deployment accuracy.

How IVUS Works

IVUS employs a tiny ultrasound probe mounted on the tip of a catheter. This catheter is inserted into the coronary arteries via the femoral or radial artery. The probe emits high-frequency sound waves, which produce real-time cross-sectional images of the vessel walls.

Why IVUS is Used

IVUS is particularly helpful in: - Assessing Plaque: Determining the thickness, type, and burden of atherosclerotic plaques. - Guiding Angioplasty: Ensuring optimal stent placement by evaluating vessel size and confirming proper stent expansion. - Detecting Complications: Identifying problems like arterial dissections or stent malapposition that might not be visible on angiography alone.

IVUS vs. Optical Coherence Tomography (OCT)

Both IVUS and OCT provide intravascular imaging, but there are differences: - IVUS: Uses sound waves, penetrates deeper, and is better for visualizing deeper structures and large arteries. - OCT: Uses light waves, provides higher resolution, but is limited by shallow tissue penetration.

Clinical Indications

IVUS is recommended in cases such as: - Complex coronary artery disease. - Unclear diagnosis after angiography. - Assessment before and after stent placement. - Evaluation of graft patency in coronary bypass surgeries.

Advantages and Limitations

Advantages:

• Provides real-time imaging of vessel walls.
• More accurate than angiography in determining lesion characteristics.
• Helps optimize interventional procedures.

Limitations:

• Requires specialized equipment and expertise.
• More expensive and time-consuming compared to traditional angiography.

Conclusion

IVUS is a valuable tool in modern cardiology, improving diagnosis and treatment outcomes for patients with coronary artery disease. It enhances the precision of percutaneous coronary interventions (PCI) and reduces the risk of complications.

References

For further reading, consult clinical guidelines by major cardiology organizations.

Source recommendations

1. American College of Cardiology/American Heart Association Guidelines on Coronary Artery Disease

1. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001168
2. https://www.acc.org/Guidelines
3. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001038
4. https://www.heart.org/
5. https://pubmed.ncbi.nlm.nih.gov/27026020/

2. European Society of Cardiology Guidelines on Myocardial Revascularization

1. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/ESC-EACTS-Guidelines-in-Myocardial-Revascularisation-Guidelines-for
2. https://academic.oup.com/eurheartj/article/40/2/87/5079120
3. https://pubmed.ncbi.nlm.nih.gov/30165437/
4. https://academic.oup.com/eurheartj/article/35/37/2541/581070
5. https://pubmed.ncbi.nlm.nih.gov/25173339/