Intravascular Imaging Flashcards
What has historically served as the gold standard for diagnosis of coronary artery disease?
Coronary angiography
Coronary angiography is crucial for diagnosing coronary artery disease and guiding interventions.
What do contemporary intravascular imaging (IVI) technologies complement?
Conventional angiography
IVI technologies enhance the characterization of plaque and optimization of PCI.
What are the three main utilities of IVI in percutaneous coronary intervention?
- Preintervention lesion and vessel assessment
- Periprocedural guidance of lesion preparation and stent deployment
- Postintervention assessment of optimal endpoints and exclusion of complications
These utilities help improve the overall outcomes of PCI.
What is emerging regarding the role of IVI in complex lesion subsets?
Reducing major adverse cardiac events
The effectiveness of IVI in preventing complications in complex cases is a developing area of research.
What does the paper advocate for regarding IVI technologies?
Broader use of these technologies as part of contemporary practice
The paper discusses best practices and supports wider implementation of IVI.
What is the primary focus of the paper regarding IVI technologies?
Overview of currently available IVI technologies and their utilization for PCI guidance
The paper reviews data supporting the use of IVI across various lesion subsets.
True or False: The paper provides a detailed analysis of the historical use of IVI technologies.
False
The focus is more on current technologies and their applications rather than historical analysis.
Fill in the blank: IVI has utility for _______ lesion and vessel assessment.
preintervention
This assessment is crucial for effective PCI.
What has been the gold standard for the diagnosis of coronary artery disease since its inception?
Coronary angiography
It is also used for guidance of percutaneous coronary intervention (PCI).
What are the inherent limitations of using 2-dimensional lumens in imaging 3-dimensional structures?
Inherent limitations persist in imaging
This has led to the development of adjunctive intravascular imaging (IVI) technologies.
What has stimulated the development of adjunctive intravascular imaging (IVI) technologies?
Limitations of 2-dimensional imaging
The aim is to improve evaluation of luminal stenoses and coronary atherosclerotic plaque.
What factors affect clinical outcomes related to PCI beyond luminal stenosis?
Vascular biology of atherosclerosis and device interaction
This includes the interaction between coronary arteries and stents.
When was intravascular ultrasound (IVUS) first developed?
Early 1970s
The first in vivo use of IVUS was described in 1988.
What year was the concept of optical coherence tomography (OCT) reported?
1991
OCT was first tested in the coronary vasculature in the early 2000s.
What advancements have been made in intravascular imaging technologies over the last several decades?
Reduction in catheter size, improvements in imaging quality and deliverability
These advancements have enhanced the effectiveness of IVI.
What is the current estimated usage rate of IVI in PCI procedures?
Less than 15%
There is significant operator and center variation in the adoption of IVI.
What are some proposed explanations for the underutilization of IVI?
Unfamiliarity with equipment, knowledge gaps, increased procedural times, lack of reimbursement
These factors contribute to the lower adoption rates of IVI.
What document provides an overview of currently available IVI techniques and best practices?
Document developed by the American College of Cardiology Interventional Council
It reviews data supporting the use of adjunctive imaging for PCI optimization.
Fill in the blank: The first in vivo use of intravascular ultrasound (IVUS) was described in _______.
1988
True or False: Optical coherence tomography (OCT) was first tested in the coronary vasculature in the late 1990s.
False
OCT was tested in the early 2000s.
What are OCT catheters designed to emit and receive?
Near-infrared light waves
OCT stands for Optical Coherence Tomography, which utilizes light waves for imaging.
What type of images do OCT catheters produce?
Real-time high spatial and contrast resolution, cross-sectional, and 3-dimensional volumetric images
This imaging capability allows for detailed visualization of vascular structures.
What is the axial resolution of OCT?
10-20 mm
This is significantly higher than that of IVUS.
What is the lateral resolution of OCT?
20-90 mm
This allows for detailed imaging of vessel structures.
How does the penetration depth of OCT compare to IVUS?
OCT has a penetration depth of 1-2 mm, while IVUS has 5-6 mm
This means OCT images are more detailed but cover a shallower area.
What is a key requirement for adequate image acquisition in OCT?
The target vessel must be cleared of blood
This often involves the use of contrast agents.
What limitations can arise when using OCT?
Challenges with ostial lesions, excessively large or small vessels, and severe stenoses
These issues stem from inadequate opacification with contrast medium.
What does the detailed image resolution of OCT allow for?
High spatial resolution and assessment of plaque morphology
This is important for understanding the characteristics of vascular lesions.
What capabilities do current OCT systems have?
Automated assessments of lesion length and luminal dimensions
This enhances the accuracy of measurements obtained during imaging.
What is angiographic coregistration in the context of OCT?
Mapping OCT findings to the coronary angiogram
This allows for a more integrated approach to vascular imaging.
What technology has been developed to aid in calcium detection in OCT?
Artificial intelligence-based methodology
This helps in assessing the extent of calcium and developing treatment algorithms.
What is the purpose of hybrid IVUS-OCT systems?
To provide both imaging modalities within a single catheter
This aims to combine the strengths of both techniques for better diagnostic capability.
What does IVUS use to create real-time cross-sectional images of blood vessels?
a) Light waves
b) Sound waves
c) X-rays
d) Magnetic fields
b) Sound waves
In IVUS, what type of structures produce brighter hyperechogenic signals?
a) Lipid collections
b) Air bubbles
c) Calcifications and fibrous tissue
d) Water
c) Calcifications and fibrous tissue
Which type of IVUS catheter design has transducer elements arranged in a circular manner?
a) Solid-state catheter
b) Mechanical-state catheter
c) Spiral catheter
d) Flexible catheter
a) Solid-state catheter
What is a primary advantage of automated pull back in IVUS imaging?
a) Allows faster imaging
b) Measures lesion length consistently
c) Improves transducer resolution
d) Reduces catheter size
b) Measures lesion length consistently
How has IVUS imaging resolution improved in newer models?
a) By increasing the frequency range between 20 to 60 MHz
b) By using mechanical pull back only
c) By eliminating the need for transducer rotation
d) By using a larger catheter size
a) By increasing the frequency range between 20 to 60 MHz
Why is careful catheter flushing important when using mechanical-state IVUS catheters?
a) To reduce time required for imaging
b) To avoid air-bubble artifacts during catheter rotation
c) To increase penetration depth
d) To enhance brightness of echogenic signals
b) To avoid air-bubble artifacts during catheter rotation
What does VH-IVUS analysis help detect in plaque assessment?
a) Blood flow rate
b) Lipid levels
c) Vulnerable plaque and thin-cap fibroatheromas
d) Calcium deposits only
c) Vulnerable plaque and thin-cap fibroatheromas
What determines the spatial resolution of an IVUS system?
a) The catheter size
b) The wavelength and beam-width of ultrasound pulses
c) The speed of the pull back
d) The frequency of the imaging platform
b) The wavelength and beam-width of ultrasound pulses
Why might IVUS be preferable over OCT in imaging aorto-ostial lesions?
a) IVUS provides higher-resolution images
b) IVUS does not require contrast for blood clearance
c) IVUS is faster to perform than OCT
d) IVUS can measure calcium thickness
b) IVUS does not require contrast for blood clearance
What is one reason IVUS may be better suited for imaging larger vascular structures like the left main coronary artery?
a) It provides higher resolution
b) It has longer wavelengths allowing deeper tissue penetration
c) It can measure calcium thickness
d) It requires less technical expertise
b) It has longer wavelengths allowing deeper tissue penetration
Which patients may benefit most from minimal contrast IVUS-guided PCI?
a) Patients with high blood pressure
b) Patients with chronic kidney disease
c) Patients with high cholesterol
d) Patients with stable coronary artery disease
b) Patients with chronic kidney disease
What advantage does OCT have over IVUS in terms of imaging resolution?
a) OCT has lower resolution than IVUS
b) OCT offers higher-resolution imaging
c) OCT can penetrate deeper tissues
d) OCT uses sound waves for imaging
b) OCT offers higher-resolution imaging
What specific feature can OCT visualize better than conventional IVUS?
a) Neoatherosclerosis in in-stent restenotic lesions
b) Residual plaque burden at stent edges
c) Large vessel lumens
d) Blood flow dynamics
a) Neoatherosclerosis in in-stent restenotic lesions
During a PCI procedure, what can OCT detect with greater sensitivity than IVUS?
a) Vessel size
b) Intimal/medial dissections
c) Patient’s blood pressure
d) Blood clearance speed
b) Intimal/medial dissections
How does OCT handle calcium differently than IVUS?
a) It cannot visualize calcium at all
b) It measures and characterizes calcium thickness
c) It uses ultrasound to bypass calcium
d) It requires high contrast for calcium visualization
b) It measures and characterizes calcium thickness
What is a disadvantage of OCT compared to IVUS?
a) OCT requires contrast for blood clearance
b) OCT has low resolution
c) OCT cannot visualize side branches
d) OCT requires specialized IVUS-compatible catheters
a) OCT requires contrast for blood clearance
What is the primary use of IVI during periprocedural guidance?
a) Blood flow analysis
b) Stent deployment and expansion
c) Reduction of vessel diameter
d) Monitoring blood pressure
b) Stent deployment and expansion
How do IVUS and OCT assist in managing coronary calcification for PCI?
a) By increasing the speed of stent deployment
b) By detecting, localizing, quantifying, and characterizing calcification
c) By replacing the need for angioplasty
d) By removing calcium deposits directly
b) By detecting, localizing, quantifying, and characterizing calcification
Why is adequate calcium fracture important before stent deployment?
a) To reduce blood flow
b) To allow better stent delivery and expansion
c) To decrease vessel diameter
d) To increase plaque burden
b) To allow better stent delivery and expansion
What IVUS characteristic indicates a risk for stent underexpansion?
a) Vessel diameter <2.0 mm
b) Calcium angle >270 degrees longer than 5 mm
c) Plaque burden >30%
d) Calcium thickness <0.5 mm
b) Calcium angle >270 degrees longer than 5 mm
Which characteristic measured by OCT predicts the need for adjunctive calcium modification?
a) Calcium thickness <0.3 mm
b) Calcium angle >180 degrees
c) Vessel diameter >4.0 mm
d) Lesion length <2 mm
b) Calcium angle >180 degrees
According to the ULTIMATE trial, what is the IVUS criterion for stent optimization regarding minimum lumen area (MLA)?
a) MLA >2.0 mm²
b) MLA >5.0 mm² or 90% of MLA at the distal reference segments
c) MLA <5.0 mm²
d) MLA 50% smaller than reference lumen
b) MLA >5.0 mm² or 90% of MLA at the distal reference segments
In the OCT “MLD-MAX” algorithm, what does the “MLD” refer to in preintervention assessment?
a) Mean lumen diameter
b) Morphology, Length, and Diameter of the lesion
c) Minimum lumen distance
d) Median lesion density
b) Morphology, Length, and Diameter of the lesion
What is a postprocedure focus in the OCT “MLD-MAX” algorithm?
a) Calcium quantification
b) Wire positioning
c) Medial dissection and stent apposition
d) Guide catheter position
c) Medial dissection and stent apposition
In the “MLD-MAX” postprocedure imaging, what does “MAX” assess?
a) Medial dissection, Apposition, eXpansion
b) Mean arterial expansion
c) Measurement of lumen depth
d) Maximum angiographic clearance
a) Medial dissection, Apposition, eXpansion
Why is distal lumen reference-based sizing considered advantageous for stent sizing?
a) It uses the largest reference lumen available
b) It is the safest and most straightforward approach
c) It allows for faster stent deployment
d) It does not require imaging guidance
b) It is the safest and most straightforward approach
What should be avoided in stent placement to reduce the risk of edge dissection and restenosis?
a) Stenting in distal segments
b) Stenting in reference segments with plaque burden >50%
c) Using short stents
d) Only using imaging-guided PCI
b) Stenting in reference segments with plaque burden >50%
What is a risk associated with stenting in vulnerable plaques with large lipid content or thin caps?
a) Faster blood flow
b) Reduced need for angioplasty
c) Higher risk of postprocedural MI and distal embolization
d) Increased calcium deposition
c) Higher risk of postprocedural MI and distal embolization
How does IVI help in determining optimal stent length and number?
a) By measuring vessel blood flow rate
b) By providing real-time stent expansion measurements
c) By optimizing stent placement and reducing procedure time
d) By reducing the use of guidewires
c) By optimizing stent placement and reducing procedure time
Which reference area can be used in measuring relative stent expansion?
a) Distal, proximal, largest, or average reference area
b) Only the distal reference area
c) Only the proximal reference area
d) The smallest vessel diameter
a) Distal, proximal, largest, or average reference area
In coronary CTO PCI, what is one role of IVUS?
a) Reducing procedure duration
b) Resolving proximal cap ambiguity and guiding true-lumen wiring
c) Increasing calcium removal
d) Automatically selecting stent size
b) Resolving proximal cap ambiguity and guiding true-lumen wiring
What is one primary use of IVI before intervention?
a) To measure blood flow speed
b) To assess plaque composition and lesion characteristics
c) To administer antiplatelet therapy
d) To avoid the need for stenting
b) To assess plaque composition and lesion characteristics
What are the typical vessel diameter ranges for the left main (LM) and proximal left anterior descending (LAD) coronary arteries?
a) LM: 3.5 mm, LAD: 2.7 mm
b) LM: 4.5 mm, LAD: 3.7 mm
c) LM: 5.5 mm, LAD: 4.7 mm
d) LM: 2.5 mm, LAD: 1.7 mm
b) LM: 4.5 mm, LAD: 3.7 mm
What procedure may be used if the imaging catheter fails to cross a lesion before planned PCI?
a) High-pressure balloon dilation
b) Low-pressure undersized balloon predilation or atherectomy
c) Administration of thrombolytic therapy
d) Use of contrast-free OCT
b) Low-pressure undersized balloon predilation or atherectomy
How can IVI assist in cases where PCI is not performed?
a) By preventing any future plaque development
b) By identifying plaques at risk of future rupture and guiding medical therapy
c) By reducing the need for future stent placement
d) By measuring myocardial blood flow
b) By identifying plaques at risk of future rupture and guiding medical therapy
In what type of case should caution be used when performing IVI?
a) Myocardial infarction with no plaque presence
b) Stable coronary artery disease
c) Spontaneous coronary artery dissection
d) Chronic stable angina
c) Spontaneous coronary artery dissection
How might IVI characterization of plaque erosion vs. rupture benefit patients in acute coronary syndrome (ACS)?
a) By allowing the use of thrombolytic agents
b) By enabling selective management with antiplatelet therapy without stenting
c) By eliminating the need for imaging altogether
d) By identifying stable plaques that need no intervention
b) By enabling selective management with antiplatelet therapy without stenting
What can IVI preintervention assessment help clarify in complex anatomy?
a) Normal coronary artery dilation
b) Aorto-ostial ambiguity, vessel dissection, and intramural hematoma
c) Simple vessel plaque buildup
d) Blood pressure fluctuations
b) Aorto-ostial ambiguity, vessel dissection, and intramural hematoma
What is one of the main purposes of postprocedure IVI?
a) To calculate blood pressure
b) To confirm optimal procedural endpoints and exclude complications
c) To avoid stent placement
d) To measure cholesterol levels
b) To confirm optimal procedural endpoints and exclude complications
When is a minor edge dissection considered unlikely to require intervention?
a) When it involves the adventitia
b) When it measures <2 mm in length and involves <45° of circumference
c) When it is located distally from the stent
d) When it extends longitudinally over 3 mm
b) When it measures <2 mm in length and involves <45° of circumference
What is “malapposition” in the context of stent placement?
a) Correct placement of stent in bifurcated vessels
b) Lack of contact of stent struts with the luminal surface area
c) Complete blockage of the artery by the stent
d) Expansion of the stent beyond vessel walls
b) Lack of contact of stent struts with the luminal surface area
What is a common cause of acute stent malapposition?
a) Use of OCT instead of IVUS
b) Implanting an undersized stent in a larger vessel
c) Overexpanding the stent beyond nominal pressure
d) Excessive contrast use
b) Implanting an undersized stent in a larger vessel
In what type of stenting does malapposition particularly increase the risk of complications?
a) Single vessel stenting
b) Bifurcation stenting
c) Peripheral artery stenting
d) Vein graft stenting
b) Bifurcation stenting
How might new computerized 3-dimensional OCT rendering be beneficial in stenting procedures?
a) By calculating blood flow rate
b) By avoiding the need for a second imaging modality
c) By providing a detailed roadmap for stent cell wiring in bifurcation stenting
d) By increasing the speed of stent deployment
c) By providing a detailed roadmap for stent cell wiring in bifurcation stenting
