How Is Intravascular Ultrasound Done? IVUS

Before the procedure

• Before the procedure, a physical examination and lab tests will be performed.
• You should inform your doctor if you have any sensitivities to certain medications.
• If you are on anticoagulants, you may need to discontinue your medication. If you are taking other blood thinners or diabetic medications, talk to your doctor.
• Fast for at least 4 hours and abstain from alcohol and smoking for at least 1 week before the surgery. 
• Bring all current medications with you to the hospital on the day of the operation.
• You may be prescribed medications to help you relax and prevent contrast sensitivities.

During the procedure

• You may be given an anticoagulant to prevent blood clots.
• Intravenous lines are used to provide medications and fluids. 
• A local anesthetic is administered to the area used to insert the catheter (groin, wrist, or inside of the elbow).
• The IVUS guidewire is inserted and threaded through the artery until it reaches the appropriate position. 
• Sound waves bounce off the artery walls and return to the transducer as echoes. 
• The echoes are transformed into visuals on a television display, resulting in a clear depiction of the coronary arteries and any potential obstructions.

After the procedure

• After the surgery, you may be escorted to a recovery area for observation and monitoring.
• To avoid bleeding, it is important to lie flat for many hours. 
• If the surgery was performed in the groin, pressure may be used to stop the bleeding.
• At the insertion location, a bandage is applied.
• Your puncture site will be sensitive for some time. It may be bruised and slightly swollen. 
• Your doctor will most likely prescribe medications to prevent blood clots. It is critical to follow your doctor's directions when using blood thinners.

Risks of the intravascular ultrasound procedure include the following:

• Dissection
• Perforation
• Arrhythmia
• Thrombosis
• Spasm

Contact your doctor if you experience any symptoms such as:

• Chest pain
• Difficulty breathing
• Sweating
• Heart palpitations
• Dizziness and fainting

Many factors, including the anatomy of your blood arteries, can impact the outcome of the surgery.

Intravascular ultrasound (IVUS) is routinely used to assess the coronary arteries, which transport oxygen-rich blood to the heart. Uses are as follows:

• Identify whether coronary artery disease caused a heart attack or is causing chest discomfort (angina)
• Treat vascular issues, such as by using stents or other ways to enhance blood flow
• Remove or filter clots, preventing them from entering the heart or brain
• Evaluate the efficacy of a certain treatment, allowing the clinician to determine whether the treatment plan has to be changed
• Visualize the complete artery wall and offer valuable information about the quantity and type of plaque accumulation, which can assist in identifying whether you are at a risk of a heart attack.
• Assist clinicians in better understanding how stents become obstructed (stent restenosis)

In addition to diagnosing coronary artery disease, IVUS can be used to diagnose and treat conditions such as:

• Carotid artery constriction (larger arteries in your neck)
• Aneurysm of the abdominal aorta
• Disease of the peripheral arteries
• Venous disease of the extremities

Parameters measured by IVUS include:

• Severity of lesions
• Underlying morphology of lesions
• Diameter and length of lesions
• Complications such as dissection
• Guide stent implantation
• Risk of stent restenosis

Advantages of IVUS

• Visualize plaque that angiography cannot 
• Used in studies to better understand how atherosclerosis occurs
• Allows visualization of not only the lumen (opening) of the coronary arteries but also the atheroma (cholesterol laden white blood cells) “hidden” within the wall

Disadvantages of IVUS

• Expensive
• Longer duration
• Classified as an interventional procedure and should only be conducted through the radiologists who have had interventional cardiology training
• Carries risks, including coronary thrombosis

Because IVUS is widely accessible in cardiac catheterization laboratories across the world and can precisely quantify arterial plaque, particularly inside the coronary arteries, it is increasingly being used to examine emerging and changing techniques for the treatment of coronary artery disease. 

IVUS helps the clinician analyze the quantity of plaque, identify the position and size of the stent, and assess treatment problems. Moreover, IVUS can help determine why a stent fails, which enables the cardiologist to plan future treatment protocols.