CTO Interventions Flashcards by Riyanna Day

What is the principal indication for performing percutaneous coronary intervention (PCI) on chronic total occlusions (CTOs)?
A) To reduce the risk of myocardial infarction
B) To improve angina and quality of life
C) To prevent arrhythmias
D) To increase overall heart function

B) To improve angina and quality of life

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What is a defining characteristic of chronic total occlusions (CTOs)?
A) Partial blockage of a coronary artery with TIMI 1 flow
B) Complete occlusion of a coronary artery with TIMI 0 flow for at least 3 months
C) A narrowing of more than 70% in a coronary artery
D) A non-occlusive clot that allows some blood flow

B) Complete occlusion of a coronary artery with TIMI 0 flow for at least 3 months

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What factors have contributed to the increased safety and success of CTO PCI?
A) New medications and alternative treatment methods
B) Improved, dedicated equipment and an algorithmic approach
C) Increased use of thrombolytic therapy
D) Reduction in the need for specialized training

B) Improved, dedicated equipment and an algorithmic approach

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Why have objective scores been developed for CTO PCI?
A) To evaluate a patient’s overall cardiac function
B) To predict long-term survival rates after PCI
C) To provide insights into the likelihood of success and potential complications
D) To determine if a patient requires bypass surgery instead

C) To provide insights into the likelihood of success and potential complications

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What is essential for cath lab staff regarding complication management during CTO PCI?
A) Knowing how to prepare the patient for surgery
B) Quickly locating and properly using complication management equipment
C) Reducing procedural time by skipping imaging steps
D) Ensuring that all CTOs are treated in the same manner

B) Quickly locating and properly using complication management equipment

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What is the typical success rate of CTO PCI at experienced centers?
A) 50-60%
B) 65-75%
C) 75-80%
D) 85-90%

D) 85-90%

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What has been developed specifically for CTO PCI to enhance procedural success?
A) New types of contrast agents
B) Specific terminology, equipment, and techniques
C) Standardized bypass surgery protocols
D) Universal drug regimens

B) Specific terminology, equipment, and techniques

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What recent development has helped unify the approach to CTO PCI worldwide?
A) A global consensus on key principles
B) Standardized reimbursement policies
C) A reduction in the number of CTO PCI procedures performed
D) Elimination of the need for operator training

A) A global consensus on key principles

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What is the principal indication for CTO PCI?
A) To improve symptoms
B) To reduce the need for medication
C) To prevent future heart attacks
D) To increase overall heart function

A) To improve symptoms

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What should be performed in every case of CTO PCI?
A) Single-plane angiography
B) Dual coronary angiography with thorough, structured review
C) Immediate stent placement
D) Routine thrombolytic therapy

B) Dual coronary angiography with thorough, structured review

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Why is a microcatheter essential in CTO PCI?
A) It provides contrast enhancement for imaging
B) It is required for delivering stents
C) It enhances guidewire support
D) It helps dissolve thrombus in the artery

C) It enhances guidewire support

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Which of the following are the four CTO crossing strategies?
A) Direct stenting, balloon angioplasty, atherectomy, and thrombolysis
B) Antegrade wire escalation, antegrade dissection/reentry, retrograde wire escalation, and retrograde dissection/reentry
C) Radial access, femoral access, hybrid access, and transapical access
D) Single-wire technique, double-wire technique, crossover technique, and scaffold technique

B) Antegrade wire escalation, antegrade dissection/reentry, retrograde wire escalation, and retrograde dissection/reentry

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How does changing equipment and technique impact the CTO PCI procedure?
A) It increases the likelihood of success and improves efficiency
B) It prolongs procedural time and increases risk
C) It decreases the chance of complications but lowers success rates
D) It is unnecessary if the first approach fails

A) It increases the likelihood of success and improves efficiency

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What should centers and physicians performing CTO PCI have to optimize success and manage complications?
A) Only basic PCI training
B) Necessary equipment, expertise, and experience
C) Access to surgical backup within 48 hours
D) A strict reliance on a single procedural technique

B) Necessary equipment, expertise, and experience

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What should be done to optimize stent deployment in CTO PCI?
A) Avoid using imaging to reduce procedural time
B) Use intravascular imaging frequently
C) Only rely on angiographic guidance
D) Deploy stents without pre-dilation

B) Use intravascular imaging frequently

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When should CTO PCI be performed?
A) In all patients with coronary artery disease
B) When the anticipated benefit outweighs the potential risk
C) Only in patients with reduced left ventricular function
D) As a first-line treatment for all cardiac conditions

B) When the anticipated benefit outweighs the potential risk

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What is the main benefit of CTO PCI?
A) Reduction in the need for medication
B) Symptom improvement, such as relief from angina and dyspnea
C) Immediate reversal of coronary artery disease
D) Elimination of arrhythmias

B) Symptom improvement, such as relief from angina and dyspnea

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How does CTO PCI benefit patients?
A) It guarantees a cure for coronary artery disease
B) It improves exercise capacity and increases the anaerobic threshold
C) It completely eliminates the risk of myocardial infarction
D) It prevents the need for lifestyle modifications

B) It improves exercise capacity and increases the anaerobic threshold

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Which additional benefit of CTO PCI remains debated?
A) Its ability to improve left ventricular systolic function
B) Its role in curing hypertension
C) Its effectiveness in lowering cholesterol levels
D) Its ability to prevent atherosclerosis progression

A) Its ability to improve left ventricular systolic function

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Which factor increases the potential benefit of CTO PCI?
A) The severity of the patient’s symptoms
B) The patient’s age
C) The presence of a single-vessel CTO
D) The absence of comorbidities

A) The severity of the patient’s symptoms

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What are potential acute risks of CTO PCI?
A) Hypertension and bradycardia
B) Acute myocardial infarction, perforation, emergency CABG, or death
C) Stroke and kidney failure
D) Atrial fibrillation and valve dysfunction

B) Acute myocardial infarction, perforation, emergency CABG, or death

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What are potential chronic risks of CTO PCI?
A) Hypertension and arrhythmias
B) Restenosis and stent thrombosis
C) Pulmonary embolism and heart failure
D) Myocarditis and pericardial effusion

B) Restenosis and stent thrombosis

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What determines the optimal coronary revascularization modality for patients with CTOs?
A) The patient’s preference alone
B) Coronary anatomy and comorbidities
C) The availability of PCI equipment
D) The operator’s personal experience

B) Coronary anatomy and comorbidities

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What is the current best practice for deciding on a revascularization strategy in patients with CTOs?
A) A decision made solely by an interventional cardiologist
B) A Heart Team approach involving cardiac surgery, cardiology, and interventional cardiology
C) Automatic referral to PCI if CTOs are present
D) Choosing CABG for all patients with CTOs

B) A Heart Team approach involving cardiac surgery, cardiology, and interventional cardiology

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In which patients is CABG often the preferred treatment for CTOs? A) Those with a single-vessel CTO and no other disease B) Those with multivessel complex coronary artery disease, especially if diabetic C) Those who have had prior CABG D) Those with normal left ventricular function

B) Those with multivessel complex coronary artery disease, especially if diabetic

In which patients is CTO PCI often the preferred treatment? A) Patients with severe multivessel disease and diabetes B) Patients who have had prior CABG, are poor surgical candidates, or have single-vessel disease C) Patients with no symptoms and normal stress tests D) Patients with non-coronary cardiac conditions

B) Patients who have had prior CABG, are poor surgical candidates, or have single-vessel disease

What recommendation does the 2021 ACC/AHA PCI guideline give for CTO PCI? A) Class I/Level A B) Class IIB/Level B C) Class III/Level C D) Class IIA/Level A

B) Class IIB/Level B

According to the 2021 ACC/AHA guidelines, in which patients is the benefit of CTO PCI considered uncertain? A) Patients with multivessel disease and diabetes B) Patients with refractory angina on medical therapy after treatment of non-CTO lesions C) Patients with completely asymptomatic CTOs D) Patients with prior coronary artery bypass graft surgery

B) Patients with refractory angina on medical therapy after treatment of non-CTO lesions

What recommendation does the 2018 ESC/EACTS guideline give for CTO PCI? A) Class I/Level A B) Class IIA/Level B C) Class III/Level C D) Class IIB/Level B

B) Class IIA/Level B

According to the 2018 ESC/EACTS guidelines, when should percutaneous recanalization of a CTO be considered? A) In all patients with coronary artery disease B) Only in patients with multivessel disease C) In patients with angina resistant to medical therapy or a large ischemic area in the affected vessel territory D) Only in patients with left ventricular dysfunction

C) In patients with angina resistant to medical therapy or a large ischemic area in the affected vessel territory

What is the main goal of CTO PCI at present? A) To completely eliminate the need for medication B) To prevent all future myocardial infarctions C) To improve patient symptoms caused by myocardial ischemia D) To increase overall life expectancy

C) To improve patient symptoms caused by myocardial ischemia

Why is a detailed conversation with patients being considered for CTO PCI important? A) To ensure full understanding of the potential risks and benefits B) To convince all patients to undergo the procedure C) To determine if the patient prefers bypass surgery instead D) To reduce the cost of treatment

A) To ensure full understanding of the potential risks and benefits

Why is dual angiography critical for CTO PCI? A) It reduces the need for guidewire manipulation B) It improves the success and safety of the procedure C) It eliminates the need for additional imaging D) It prevents restenosis after stent placement

B) It improves the success and safety of the procedure

In which case is dual angiography NOT required for CTO PCI? A) When the patient has undergone prior PCI B) When the collateral circulation originates exclusively from the CTO vessel C) When the CTO is less than 5 mm in length D) When the patient has multivessel coronary artery disease

B) When the collateral circulation originates exclusively from the CTO vessel

What is the correct sequence for injecting contrast during dual angiography in CTO PCI? A) Inject the CTO vessel first, then the donor vessel B) Inject both vessels simultaneously C) Inject the donor vessel first, followed by the CTO vessel 2 to 3 seconds later D) Inject only the donor vessel to prevent complications

C) Inject the donor vessel first, followed by the CTO vessel 2 to 3 seconds later

What additional imaging technique can help assess CTO vessel anatomy? A) Intravascular ultrasound (IVUS) B) Coronary computed tomography angiography (CCTA) C) Fluoroscopy alone D) Echocardiography

B) Coronary computed tomography angiography (CCTA)

What are the four key angiographic characteristics reviewed when assessing CTO anatomy? A) Proximal cap morphology, occlusion length/course/composition, quality of the distal vessel, and collateral circulation B) Vessel diameter, patient age, plaque density, and procedural time C) Angiographic contrast uptake, lesion temperature, patient heart rate, and calcium score D) Flow rate, blood pressure, lesion location, and myocardial thickness

A) Proximal cap morphology, occlusion length/course/composition, quality of the distal vessel, and collateral circulation

Why is it important to review non-CTO lesions during angiographic assessment? A) To determine the optimal revascularization strategy (PCI vs. CABG) and the sequence of lesion treatment B) To decide whether to use radial or femoral access C) To confirm the presence of a CTO D) To reduce the radiation dose needed for the procedure

A) To determine the optimal revascularization strategy (PCI vs. CABG) and the sequence of lesion treatment

Why is proximal cap ambiguity important in CTO PCI? A) It determines stent sizing B) It affects the selection of crossing strategies and can increase the risk of perforation C) It helps in selecting the appropriate anticoagulant therapy D) It is only relevant for non-CTO lesions

B) It affects the selection of crossing strategies and can increase the risk of perforation

Which of the following imaging techniques can help identify the location of the proximal cap? A) Fluoroscopy alone B) Dual injection angiography, microcatheter contrast injection, IVUS, and CCTA C) Electrocardiography (ECG) D) Stress echocardiography

B) Dual injection angiography, microcatheter contrast injection, IVUS, and CCTA

What is the risk of attempting to cross an ambiguous proximal cap without proper imaging? A) Increased risk of restenosis B) Increased risk of perforation C) Increased risk of arrhythmias D) Increased risk of heart failure

B) Increased risk of perforation

If the location of the proximal cap remains unclear despite additional imaging, what strategies can be used? A) Radial access and thrombolytic therapy B) Retrograde approach or “move the cap” dissection/reentry techniques C) Direct stenting without guidewire manipulation D) Balloon angioplasty only

B) Retrograde approach or “move the cap” dissection/reentry techniques

What role does intravascular ultrasound (IVUS) play in assessing the proximal cap? A) It helps determine the exact location and characteristics of the proximal cap B) It replaces the need for dual injection angiography C) It measures overall heart function rather than specific lesion details D) It is used only after the CTO has been crossed

A) It helps determine the exact location and characteristics of the proximal cap

Why does antegrade-only injection often lead to an overestimation of lesion length? A) It causes excessive contrast pooling B) It results in underfilling and poor opacification of the distal vessel due to competing antegrade and retrograde flow C) It enhances visualization of the lesion, making it appear longer D) It prevents the identification of calcification

B) It results in underfilling and poor opacification of the distal vessel due to competing antegrade and retrograde flow

What factors can make crossing a CTO particularly challenging? A) Large vessel diameter and short lesion length B) Severe calcification and tortuosity of the occluded segment C) High blood pressure and increased heart rate D) The presence of a collateral vessel

B) Severe calcification and tortuosity of the occluded segment

What technique is preferred when the vessel course is unclear or highly tortuous? A) Direct stenting B) Use of a knuckled (J-shaped) guidewire or retrograde approach C) Administration of thrombolytic agents D) Avoiding contrast injection

B) Use of a knuckled (J-shaped) guidewire or retrograde approach

Why is a knuckled (J-shaped) guidewire useful in highly tortuous CTOs? A) It advances within the vessel architecture with a low risk of perforation B) It dissolves thrombus and restores blood flow C) It is more rigid and provides better pushability D) It eliminates the need for dual injection imaging

A) It advances within the vessel architecture with a low risk of perforation

What is a common challenge when identifying the location and morphology of the distal cap? A) Poor guidewire support B) The presence of competing antegrade and retrograde flow C) The inability of angiography to detect CTOs D) The use of high magnification imaging

B) The presence of competing antegrade and retrograde flow

Why are CTO vessels with small and diffusely diseased distal segments more challenging to recanalize? A) They always require surgical intervention B) They increase the risk of stent thrombosis C) They are more difficult to navigate, especially after subintimal guidewire entry D) They prevent the use of intravascular imaging

C) They are more difficult to navigate, especially after subintimal guidewire entry

Why might distal vessels appear small before CTO recanalization? A) They have naturally smaller diameters B) They experience hypoperfusion, which may improve after recanalization C) They are unaffected by the presence of the CTO D) They contain excessive thrombus that permanently reduces vessel size

B) They experience hypoperfusion, which may improve after recanalization

How can distal vessel calcification affect guidewire advancement? A) It prevents the use of a microcatheter B) It may hinder reentry into the true lumen if the guidewire is in a subintimal position C) It makes antegrade wire escalation the only viable approach D) It increases contrast retention, making visualization easier

B) It may hinder reentry into the true lumen if the guidewire is in a subintimal position

What happens to some distal vessels after successful CTO PCI? A) They may increase in size due to restored blood flow B) They become more tortuous and difficult to access C) They develop new collaterals to compensate for the intervention D) They remain unchanged in size and function

A) They may increase in size due to restored blood flow

What is a potential consequence of subintimal guidewire positioning in a calcified distal vessel? A) It may make reentry into the true lumen more difficult B) It enhances the guidewire's ability to cross the lesion C) It leads to immediate vessel dilation D) It eliminates the need for stenting

A) It may make reentry into the true lumen more difficult

Why is assessing collateral circulation critical in CTO PCI? A) It determines the feasibility of the retrograde approach B) It eliminates the need for dual angiography C) It helps predict restenosis rates D) It identifies the best stent size for PCI

A) It determines the feasibility of the retrograde approach

What is the preferred imaging method for assessing collateral circulation? A) Single-vessel angiography with panning B) High-quality dual angiography obtained during breath hold and without panning C) Stress echocardiography D) Computed tomography angiography (CCTA) alone

B) High-quality dual angiography obtained during breath hold and without panning

Through which structures can a retrograde crossing be attempted? A) Septal collaterals, epicardial collaterals, or bypass grafts B) Pulmonary arteries, septal collaterals, or renal arteries C) Aortic branches, epicardial collaterals, or venous grafts D) Coronary veins, epicardial collaterals, or peripheral arteries

A) Septal collaterals, epicardial collaterals, or bypass grafts

What factors affect the ability to cross a collateral vessel with a guidewire? A) Guidewire coating and length only B) Vessel size, tortuosity, bifurcations, angle of entry/exit, and distance from exit to distal cap C) Patient age and prior medication use D) Length of the CTO and degree of arterial hypertension

B) Vessel size, tortuosity, bifurcations, angle of entry/exit, and distance from exit to distal cap

How is collateral vessel size often assessed? A) TIMI flow grading B) Werner classification (CC0, CC1, CC2) C) SYNTAX score D) FFR (Fractional Flow Reserve)

B) Werner classification (CC0, CC1, CC2)

What is the “surfing technique” in crossing collaterals? A) Advancing a guidewire with simultaneous rotation without angiographic guidance B) Injecting contrast into the collateral and waiting for spontaneous perfusion C) Using high-pressure balloon inflation to open the collateral D) Placing a stent before crossing the collateral vessel

A) Advancing a guidewire with simultaneous rotation without angiographic guidance

What is a potential challenge with previously visualized collaterals during the procedure? A) They often become more tortuous, making PCI impossible B) They may disappear but still be crossable C) They require pre-dilation with large balloons before use D) They always provide the main access for a retrograde approach

B) They may disappear but still be crossable

Why are aortocoronary bypass grafts often favorable retrograde conduits? A) They are naturally resistant to restenosis B) They have fewer side branches, a predictable course, and a large caliber C) They provide immediate antegrade flow restoration D) They require no guidewire support for successful crossing

B) They have fewer side branches, a predictable course, and a large caliber

Why are septal collaterals preferred over epicardial collaterals for retrograde crossing? A) They have lower risk of perforation causing tamponade B) They have a larger diameter in all patients C) They do not require guidewire support D) They are more resistant to occlusion after PCI

A) They have lower risk of perforation causing tamponade

What type of guidewire is typically used to navigate septal collaterals? A) Rigid and hydrophilic guidewires B) Very soft tip and polymer-jacketed guidewires C) Balloon-tipped guidewires D) Bare metal guidewires

B) Very soft tip and polymer-jacketed guidewires

What is the primary purpose of CTO scoring systems? A) To predict restenosis rates after PCI B) To estimate the difficulty of CTO PCI and the likelihood of success and complications C) To determine the best stent type for a given lesion D) To identify which patients should be referred directly for CABG

B) To estimate the difficulty of CTO PCI and the likelihood of success and complications

What is the most commonly used CTO score? A) SYNTAX score B) TIMI flow grading C) J-CTO score D) FFR-CTO score

C) J-CTO score

What factors are included in the J-CTO score? A) Vessel diameter, TIMI flow, and prior myocardial infarction B) At least 1 bend > 45 degrees, occlusion length > 20 mm, calcification, blunt proximal stump, and previously failed attempt C) Patient age, diabetes status, and renal function D) Plaque composition, heart rate, and blood pressure

B) At least 1 bend > 45 degrees, occlusion length > 20 mm, calcification, blunt proximal stump, and previously failed attempt

Which CTO score is specifically designed to estimate antegrade guidewire crossing success within 30 minutes? A) PROGRESS-CTO score B) J-CTO score C) CASTLE score D) CL-score

B) J-CTO score

What does the CASTLE score assess? A) Coronary microvascular function B) The likelihood of CTO PCI success in retrograde procedures C) CABG history, Age ≥ 70 years, Stump anatomy, Tortuosity degree, Lesion length ≥ 20 mm, and Extent of calcification D) The need for dual antiplatelet therapy after PCI

C) CABG history, Age ≥ 70 years, Stump anatomy, Tortuosity degree, Lesion length ≥ 20 mm, and Extent of calcification

Which CTO score is derived from a multicenter registry focusing on Crossboss and Hybrid procedures? A) RECHARGE score B) PROGRESS-CTO score C) J-CTO score D) CT-RECTOR score

A) RECHARGE score

What differentiates the CT-RECTOR and Korean Multicenter CTO CT Registry scores from other CTO scores? A) They are based on computed tomography angiography (CCTA) rather than invasive angiography B) They only assess patients undergoing CABG C) They focus exclusively on stent deployment techniques D) They predict the likelihood of stent thrombosis rather than procedural success

A) They are based on computed tomography angiography (CCTA) rather than invasive angiography

Which score is known as the PROGRESS-CTO score? A) A score that evaluates the probability of successful CTO PCI based on procedural complexity and clinical factors B) A score that determines the need for intravascular imaging C) A scoring system designed for acute coronary syndromes D) A tool for predicting restenosis risk after stent placement

A) A score that evaluates the probability of successful CTO PCI based on procedural complexity and clinical factors

Why is lesion calcification included in multiple CTO scoring systems? A) It predicts an increased likelihood of guidewire failure and procedural difficulty B) It determines which anticoagulant should be used post-PCI C) It eliminates the need for retrograde approaches D) It makes CTO PCI easier to perform

A) It predicts an increased likelihood of guidewire failure and procedural difficulty

What is a common feature across most CTO scoring systems? A) They consider lesion characteristics such as length, tortuosity, and calcification B) They focus only on the presence of collateral circulation C) They exclude cases with prior CABG D) They rely exclusively on non-invasive imaging

A) They consider lesion characteristics such as length, tortuosity, and calcification

What are the three variables used in the Progress-CTO complications score? A) Age ≥ 65 years, lesion length > 23 mm, and use of the retrograde approach B) Diabetes, prior myocardial infarction, and lesion tortuosity C) TIMI flow grade, presence of collaterals, and patient gender D) Proximal cap ambiguity, vessel calcification, and presence of a blunt stump

A) Age ≥ 65 years, lesion length > 23 mm, and use of the retrograde approach

What is the primary purpose of the Progress-CTO complications score? A) To determine the need for dual antiplatelet therapy B) To assess the risk of periprocedural complications in CTO PCI C) To evaluate the success rate of CABG procedures D) To predict the likelihood of long-term restenosis after PCI

B) To assess the risk of periprocedural complications in CTO PCI

How can CTO scoring facilitate decision-making? A) By automatically selecting the best PCI technique for every case B) By helping determine whether medical therapy or CTO PCI is preferable based on lesion complexity C) By identifying the optimal stent type and size for deployment D) By eliminating the need for preprocedural angiographic review

B) By helping determine whether medical therapy or CTO PCI is preferable based on lesion complexity

What type of CTOs are more likely to require dissection reentry and retrograde crossing techniques? A) Simple CTOs with a J-CTO score of 0 B) Complex CTOs with a J-CTO score ≥ 2 C) CTOs with TIMI 3 flow D) CTOs that have been successfully treated with medical therapy

B) Complex CTOs with a J-CTO score ≥ 2

Why should complex CTO PCI cases be performed by experienced operators? A) They require advanced techniques like dissection reentry and retrograde crossing B) They have a lower success rate regardless of operator experience C) They involve higher radiation exposure that only experienced operators can manage D) They can only be completed at academic medical centers

A) They require advanced techniques like dissection reentry and retrograde crossing

Which online resource provides calculators for multiple CTO scores? A) www.ctomanual.org/cto-scores B) www.ctopredictor.com C) www.cardiologycalculator.net D) www.angiogramanalysis.org

A) www.ctomanual.org/cto-scores

In which scenario might medical therapy be preferred over CTO PCI? A) In patients with mild symptoms and highly complex occlusions B) In patients with ongoing myocardial infarction C) In patients with single-vessel CTO and severe angina D) In patients with well-developed collaterals and no ischemia

A) In patients with mild symptoms and highly complex occlusions

Why is lesion length > 23 mm included in the Progress-CTO complications score? A) Longer lesions are associated with increased procedural difficulty and complications B) Longer lesions require less guidewire manipulation C) Lesion length does not affect procedural success D) It predicts better long-term stent patency

A) Longer lesions are associated with increased procedural difficulty and complications

What is a key limitation of CTO scores? A) They require detailed angiographic review and cannot replace clinical judgment B) They only apply to patients undergoing CABG C) They do not consider lesion calcification or tortuosity D) They are unreliable for predicting procedural success

A) They require detailed angiographic review and cannot replace clinical judgment

Why is the retrograde approach a risk factor in the Progress-CTO complications score? A) It carries a higher risk of complications such as vessel perforation and tamponade B) It is associated with lower procedural success rates C) It always requires the use of intravascular imaging D) It is only used in cases with severe left ventricular dysfunction

A) It carries a higher risk of complications such as vessel perforation and tamponade

What is often the most challenging step of CTO PCI? A) Selecting the appropriate stent size B) Advancing a guidewire through the occlusion C) Administering contrast for angiography D) Managing post-PCI restenosis

B) Advancing a guidewire through the occlusion

What is the primary purpose of using a microcatheter in CTO PCI? A) To inject contrast media more efficiently B) To support the guidewire, facilitate exchanges, and improve tip reshaping C) To deliver a drug-eluting stent directly into the occlusion D) To measure fractional flow reserve (FFR) before crossing the CTO

B) To support the guidewire, facilitate exchanges, and improve tip reshaping

How do microcatheters enhance guidewire performance in CTO PCI? A) They reduce penetration force when advanced closer to the guidewire tip B) They increase penetration force when advanced closer to the guidewire tip C) They eliminate the need for dual angiography D) They automatically select the correct guidewire for the procedure

B) They increase penetration force when advanced closer to the guidewire tip

What additional role do microcatheters play in the retrograde approach? A) They help cross collateral channels and protect them from wire-induced trauma B) They replace the need for guide catheter support C) They eliminate the risk of vessel perforation D) They prevent the need for guidewire tip reshaping

A) They help cross collateral channels and protect them from wire-induced trauma

What factor should influence microcatheter selection in CTO PCI? A) The presence of non-CTO lesions B) The availability, lesion characteristics, and operator expertise C) The patient’s renal function D) The size of the coronary sinus

B) The availability, lesion characteristics, and operator expertise

What technique can enhance guide catheter support to facilitate CTO crossing? A) Using smaller guide catheters for flexibility B) Using larger guide catheters or guide catheter extensions C) Relying exclusively on antegrade wiring techniques D) Performing the procedure without fluoroscopy

B) Using larger guide catheters or guide catheter extensions

How are CTO crossing techniques classified? A) By whether intravascular imaging is used B) By lesion calcification severity C) By wiring direction (antegrade vs. retrograde) and subintimal space usage (wiring vs. dissection and reentry) D) By patient symptoms and pre-existing comorbidities

C) By wiring direction (antegrade vs. retrograde) and subintimal space usage (wiring vs. dissection and reentry)

Why is strong guide catheter support important in CTO PCI? A) It stabilizes the coronary arteries during the procedure B) It allows for better contrast injection C) It facilitates guidewire crossing by improving pushability and support D) It eliminates the need for microcatheters

C) It facilitates guidewire crossing by improving pushability and support

What is a potential consequence of not using a microcatheter when attempting CTO PCI? A) Increased risk of guidewire-induced trauma and difficulty in crossing the lesion B) Automatic success of the procedure C) Decreased procedure time due to fewer device exchanges D) Complete elimination of the need for stenting

A) Increased risk of guidewire-induced trauma and difficulty in crossing the lesion

In what scenario is a retrograde CTO crossing strategy commonly used? A) When the antegrade approach is unsuccessful or unfavorable due to proximal cap ambiguity B) When the lesion is short and easily crossed C) When there is no collateral circulation present D) When the patient has previously undergone CABG

A) When the antegrade approach is unsuccessful or unfavorable due to proximal cap ambiguity

What is the most commonly used CTO crossing technique? A) Retrograde wiring B) Antegrade wiring C) Dissection and reentry D) Subintimal tracking

B) Antegrade wiring

How does antegrade wiring advance the guidewire? A) Against the original direction of blood flow B) In the original direction of blood flow C) Perpendicular to the vessel wall D) Directly into the subintimal space

B) In the original direction of blood flow

What type of guidewire is typically used initially for CTOs with a tapered proximal cap? A) High-penetration-force guidewire B) Polymer-jacketed, low-penetration-force, tapered guidewire C) Bare-metal wire with no coating D) Soft-tipped coronary guidewire

B) Polymer-jacketed, low-penetration-force, tapered guidewire

When would an operator escalate to an intermediate- or high-penetration-force guidewire? A) If the patient has a history of CABG B) If the initial guidewire fails to cross the lesion C) If the lesion is located in the right coronary artery D) If the vessel diameter is less than 2.0 mm

B) If the initial guidewire fails to cross the lesion

What type of guidewire is often used for CTOs with a blunt proximal cap? A) Polymer-jacketed, low-penetration-force guidewire B) Intermediate-penetration-force polymer-jacketed or composite core guidewire C) Stiff, high-penetration-force guidewire D) Soft, hydrophilic-coated guidewire

B) Intermediate-penetration-force polymer-jacketed or composite core guidewire

In which scenario is a stiff, high-penetration-force guidewire often required? A) In cases of well-developed collateral circulation B) When encountering highly resistant proximal caps or areas of resistance within the occlusion C) When performing primary PCI for acute myocardial infarction D) When assessing fractional flow reserve (FFR)

B) When encountering highly resistant proximal caps or areas of resistance within the occlusion

What should be done after a stiff, high-penetration-force guidewire successfully crosses the areas of resistance? A) It should be left in place for the duration of the procedure B) It should be changed to a less penetrating guidewire (de-escalation) C) It should be removed and replaced with a balloon catheter D) It should be used to perform intravascular imaging

B) It should be changed to a less penetrating guidewire (de-escalation)

Why is de-escalation to a less penetrating guidewire recommended after crossing areas of resistance? A) To reduce the risk of vessel injury and improve navigation through the CTO segment B) To increase the guidewire's penetration force C) To prepare the lesion for immediate stent deployment D) To ensure rapid completion of the procedure

A) To reduce the risk of vessel injury and improve navigation through the CTO segment

What is a potential disadvantage of using high-penetration-force guidewires throughout the entire CTO PCI procedure? A) Increased risk of vessel perforation and complications B) Inability to cross highly calcified lesions C) Reduced ability to perform retrograde approaches D) Incompatibility with microcatheters

A) Increased risk of vessel perforation and complications

What factor primarily determines the choice of guidewire in antegrade wiring? A) Operator preference alone B) CTO lesion characteristics C) Patient symptoms D) Availability of dual antiplatelet therapy

B) CTO lesion characteristics

What imaging techniques help determine guidewire position during CTO crossing attempts? A) Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) B) Contralateral injection and orthogonal angiographic projections C) Fractional flow reserve (FFR) and coronary computed tomography angiography (CCTA) D) Electrocardiography (ECG) and echocardiography

B) Contralateral injection and orthogonal angiographic projections

Once the guidewire successfully enters the distal true lumen, what is the next step? A) Remove the guidewire and restart the procedure B) Advance a microcatheter into the distal true lumen and exchange for a workhorse guidewire C) Immediately perform balloon angioplasty without guidewire exchange D) Deploy a stent over the initial guidewire without further steps

B) Advance a microcatheter into the distal true lumen and exchange for a workhorse guidewire

Why is a workhorse guidewire used after crossing a CTO? A) To reduce the risk of distal vessel injury and perforation during balloon angioplasty and stenting B) To increase penetration force for better lesion crossing C) To visualize the vessel anatomy more clearly D) To prevent the need for balloon angioplasty

A) To reduce the risk of distal vessel injury and perforation during balloon angioplasty and stenting

What should be done if the guidewire exits the vessel architecture? A) Advance the microcatheter over it B) Withdraw and redirect the guidewire without advancing other equipment C) Immediately perform balloon dilation D) Proceed with stent implantation to secure the wire position

B) Withdraw and redirect the guidewire without advancing other equipment

What is the parallel wire technique? A) Using two microcatheters simultaneously to cross the lesion B) Leaving a subintimal guidewire in place as a marker while advancing a second guidewire into the distal true lumen C) Using two workhorse guidewires in parallel for additional support D) Advancing a balloon catheter alongside the guidewire to facilitate crossing

B) Leaving a subintimal guidewire in place as a marker while advancing a second guidewire into the distal true lumen

If the guidewire enters the subintimal space, what are the possible strategies to reach the distal true lumen? A) Redirect the guidewire, use the parallel wire technique, or employ antegrade dissection/reentry B) Inflate a balloon to compress the subintimal space C) Deploy a stent directly into the subintimal space D) Withdraw the guidewire and restart the procedure

A) Redirect the guidewire, use the parallel wire technique, or employ antegrade dissection/reentry

What is a potential risk of advancing a subintimal guidewire beyond the distal cap? A) Increased risk of vessel spasm B) Hematoma formation causing luminal compression and hindering guidewire crossing C) Accidental advancement into the collateral circulation D) Decreased likelihood of restenosis

B) Hematoma formation causing luminal compression and hindering guidewire crossing

When using antegrade dissection/reentry techniques, what is the goal? A) To completely bypass the occlusion without reentering the distal lumen B) To reenter the distal true lumen after subintimal navigation C) To perforate the vessel wall intentionally for collateral formation D) To convert the CTO into a partially occluded lesion

B) To reenter the distal true lumen after subintimal navigation

If the guidewire enters the distal true lumen, why is it important to advance the microcatheter before exchanging for a workhorse guidewire? A) To ensure the guidewire is securely positioned before proceeding with intervention B) To allow contrast injection for better visualization C) To increase guidewire penetration force D) To prepare for a retrograde approach

A) To ensure the guidewire is securely positioned before proceeding with intervention

Which approach should be avoided if the guidewire is in the subintimal space? A) Using the parallel wire technique B) Advancing the subintimal guidewire distal to the distal cap C) Employing antegrade dissection/reentry techniques D) Redirecting the guidewire into the distal true lumen

B) Advancing the subintimal guidewire distal to the distal cap

What is the primary goal of antegrade dissection and reentry in CTO PCI? A) To create a new collateral circulation B) To intentionally dissect the vessel and reenter the distal true lumen C) To perform retrograde crossing through collateral channels D) To completely avoid the use of guidewires

B) To intentionally dissect the vessel and reenter the distal true lumen

What was the first dissection/reentry technique developed for CTO PCI? A) Parallel wire technique B) STAR (Subintimal Tracking And Reentry) technique C) Reverse CART technique D) Surfing technique

B) STAR (Subintimal Tracking And Reentry) technique

What is a major drawback of the STAR technique? A) It cannot be used in highly calcified lesions B) It often requires stenting long coronary segments, leading to high rates of restenosis and reocclusion C) It cannot be performed using a knuckled wire D) It increases the likelihood of side branch preservation

B) It often requires stenting long coronary segments, leading to high rates of restenosis and reocclusion

When is the STAR technique currently used in clinical practice? A) As a primary technique for CTO PCI B) Only for bailout situations and in preparation for a repeat CTO PCI attempt C) To perform retrograde CTO crossing D) To visualize the coronary artery anatomy

B) Only for bailout situations and in preparation for a repeat CTO PCI attempt

What is the primary advantage of limited antegrade dissection/reentry techniques over the STAR technique? A) They allow for longer dissection segments B) They minimize vascular injury and stent length C) They eliminate the need for guidewire manipulation D) They increase the risk of side branch occlusion

B) They minimize vascular injury and stent length

Which specialized device is commonly used for limited antegrade dissection/reentry techniques? A) CrossBoss catheter B) Stingray balloon C) Cutting balloon D) Optical coherence tomography (OCT)

B) Stingray balloon

Why are limited dissection/reentry techniques preferred over traditional STAR techniques? A) They facilitate reentry immediately distal to the distal cap B) They require longer stenting C) They use retrograde techniques exclusively D) They increase the risk of reocclusion

A) They facilitate reentry immediately distal to the distal cap

What is the primary goal of the subintimal plaque modification or “investment” procedure? A) To immediately restore full blood flow B) To prepare the lesion for a repeat CTO PCI attempt C) To avoid the use of guidewires altogether D) To permanently occlude the vessel

B) To prepare the lesion for a repeat CTO PCI attempt

How does the Stingray balloon facilitate reentry into the distal true lumen? A) By creating a controlled puncture into the distal true lumen B) By knuckling a wire through the occlusion C) By inflating and compressing the occlusion until blood flow is restored D) By dissolving the occlusive plaque

A) By creating a controlled puncture into the distal true lumen

What is a key benefit of using limited antegrade dissection/reentry techniques? A) They allow reentry at any location within the vessel B) They improve side branch preservation and reduce restenosis risk C) They completely eliminate the need for stenting D) They are exclusively used in retrograde procedures

B) They improve side branch preservation and reduce restenosis risk

In the retrograde approach for CTO PCI, how is the guidewire advanced? A) In the original direction of blood flow B) Against the original direction of blood flow C) Only through the antegrade route D) Without using a microcatheter

B) Against the original direction of blood flow

Which anatomical structures can be used for retrograde CTO crossing? A) Native coronary arteries only B) Collateral channels or bypass grafts C) Only large-diameter arteries D) Veins adjacent to the occlusion

B) Collateral channels or bypass grafts

What is the primary purpose of a microcatheter in the retrograde approach? A) To provide support for the guidewire and facilitate exchanges B) To inflate and dilate the occlusion directly C) To dissolve the occlusion using pharmacological agents D) To bypass the occlusion without guidewire use

A) To provide support for the guidewire and facilitate exchanges

When is retrograde wiring typically preferred? A) For long occlusions with significant calcification B) For short occlusions, especially when the distal cap is tapered C) When antegrade wiring has already been successful D) Only in cases of total vessel occlusion without collaterals

B) For short occlusions, especially when the distal cap is tapered

What is the most commonly used retrograde crossing technique? A) Parallel wire technique B) STAR technique C) Reverse controlled antegrade and retrograde tracking (reverse CART) D) Direct stenting

C) Reverse controlled antegrade and retrograde tracking (reverse CART)

How does the reverse CART technique facilitate guidewire crossing? A) A balloon is inflated over the antegrade guidewire, creating space for the retrograde guidewire to advance B) The guidewire is advanced blindly through the occlusion C) A microcatheter is inserted directly into the occlusion to dissolve the plaque D) The retrograde guidewire is used alone without any antegrade assistance

A) A balloon is inflated over the antegrade guidewire, creating space for the retrograde guidewire to advance

What additional tools can assist in challenging reverse CART cases? A) Optical coherence tomography (OCT) B) Intravascular ultrasound (IVUS) or guide catheter extensions C) Only high-penetration guidewires D) Manual aspiration catheters

B) Intravascular ultrasound (IVUS) or guide catheter extensions

What is the main advantage of the retrograde approach in CTO PCI? A) It avoids the need for dual angiography B) It allows for CTO crossing when antegrade techniques fail C) It eliminates the need for guidewires D) It is the easiest technique for all CTO cases

B) It allows for CTO crossing when antegrade techniques fail

Which of the following is NOT a common access point for the retrograde approach? A) Septal collaterals B) Epicardial collaterals C) Aortocoronary bypass grafts D) The femoral vein

D) The femoral vein

In the retrograde approach, why is guidewire crossing through collateral channels challenging? A) Collateral vessels are often tortuous and have sharp angulations B) The guidewire cannot be visualized fluoroscopically C) The retrograde approach does not use guidewires D) Collaterals are always too small to allow crossing

A) Collateral vessels are often tortuous and have sharp angulations

What is the preferred initial crossing strategy in most CTO PCI algorithms? A) Retrograde crossing B) Antegrade crossing C) Use of dual angiography D) Bypass surgery

B) Antegrade crossing

What is a primary retrograde approach most commonly needed for? A) CTOs with large collateral vessels B) CTOs with proximal cap ambiguity that cannot be resolved using other techniques C) CTOs with mild calcification D) CTOs that are less than 10 mm in length

B) CTOs with proximal cap ambiguity that cannot be resolved using other techniques

Which of the following is a key reason for selecting antegrade crossing over retrograde crossing as the initial strategy? A) Retrograde crossing requires less equipment B) Antegrade crossing does not carry any risks C) Antegrade lesion preparation is necessary even if retrograde crossing is eventually used D) Retrograde crossing is more reliable in all cases

C) Antegrade lesion preparation is necessary even if retrograde crossing is eventually used

What is one of the challenges associated with the retrograde approach in CTO PCI? A) It always results in a higher risk of restenosis B) It requires no operator expertise C) It carries a higher risk of complications compared to antegrade crossing D) It always involves a higher success rate

C) It carries a higher risk of complications compared to antegrade crossing

Which of the following algorithms is commonly used for CTO PCI crossing strategy selection? A) Hybrid, Asia Pacific, and Euro-CTO algorithms B) PCI Classification Algorithm C) CTO Failure Risk Algorithm D) Coronary Artery Bypass Strategy

A) Hybrid, Asia Pacific, and Euro-CTO algorithms

Why is the retrograde approach considered more complex than antegrade crossing? A) It involves more advanced equipment B) It requires a higher level of operator experience to minimize complications C) It is less effective for complex CTOs D) It cannot be performed in flush aorto-ostial CTOs

B) It requires a higher level of operator experience to minimize complications

What could be a consequence of antegrade crossing attempts when the retrograde approach is eventually needed? A) There are fewer complications B) Complications may arise due to the prior antegrade attempts C) The retrograde approach becomes unnecessary D) There is no impact on the procedure

B) Complications may arise due to the prior antegrade attempts

In complex CTOs, how has the retrograde approach affected success rates? A) It has decreased success rates in all cases B) It has no impact on success rates C) It has significantly increased success rates, especially in more complex CTOs D) It has only increased success rates in simpler CTOs

C) It has significantly increased success rates, especially in more complex CTOs

When might a retrograde approach be necessary as the primary strategy in CTO PCI? A) When there is a tapered proximal cap B) In CTOs that cannot be crossed using antegrade methods due to high resistance C) When the patient is unable to tolerate any form of intervention D) In flush aorto-ostial CTOs or unresolved proximal cap ambiguity

D) In flush aorto-ostial CTOs or unresolved proximal cap ambiguity

What is a potential downside to using the retrograde approach in CTO PCI? A) It always leads to a longer procedure time B) It may lead to more complex complications that require experienced operators to manage C) It can only be used when antegrade crossing fails D) It results in poorer clinical outcomes than other methods

B) It may lead to more complex complications that require experienced operators to manage

When is it typically necessary to change the initially selected crossing strategy in CTO PCI? A) After every guidewire advancement B) When the initially selected strategy fails to cross the CTO C) Only after the first attempt has been completed successfully D) If the CTO lesion is less than 10 mm in length

B) When the initially selected strategy fails to cross the CTO

What is an example of a minor change in the CTO PCI procedure when the selected strategy is not working? A) Switching from a guidewire to a balloon B) Changing the angiographic imaging technique C) Reshaping the guidewire tip or changing the guidewire or microcatheter D) Changing from a retrograde to an antegrade approach

C) Reshaping the guidewire tip or changing the guidewire or microcatheter

What is an example of a bigger change in crossing strategy? A) Using a higher-dose contrast B) Changing from antegrade wiring to antegrade dissection/reentry or retrograde crossing C) Reducing radiation exposure D) Switching to medical therapy instead of PCI

B) Changing from antegrade wiring to antegrade dissection/reentry or retrograde crossing

What factors influence the decision of when and how to change the CTO PCI crossing strategy? A) Operator experience, preprocedural planning, risk of alternative strategies, and progress of the procedure B) The patient’s age and comorbidities C) The length of the CTO lesion D) The availability of contrast media

A) Operator experience, preprocedural planning, risk of alternative strategies, and progress of the procedure

How does persisting with strategies that are failing to achieve progress affect the procedure? A) It can increase contrast and radiation dose, reducing the likelihood of success B) It guarantees the procedure will be completed successfully C) It reduces the overall procedure time D) It improves the visibility of collateral circulation

A) It can increase contrast and radiation dose, reducing the likelihood of success

Who is typically faster at implementing changes in crossing strategy during CTO PCI? A) Less experienced operators B) More experienced operators C) Operators using only antegrade crossing techniques D) Operators using only retrograde crossing techniques

B) More experienced operators

What should an operator consider when deciding whether to persist with or change a crossing strategy? A) The likelihood of complications occurring during the procedure B) The patient's preference regarding treatment C) Whether the current strategy is progressing toward success D) The amount of contrast already used

C) Whether the current strategy is progressing toward success

What is the effect of continuing with a strategy that is not working during a CTO PCI procedure? A) It helps in obtaining better collateral circulation B) It increases the success rate of the procedure C) It can lead to an unnecessary increase in radiation and contrast dose D) It allows for more precise targeting of the CTO cap

C) It can lead to an unnecessary increase in radiation and contrast dose

Why is it important to make timely changes to the CTO PCI strategy? A) To reduce the total procedure time B) To ensure maximum contrast is used for better imaging C) To minimize contrast and radiation dose while improving the chances of success D) To ensure that the retrograde approach is always used

C) To minimize contrast and radiation dose while improving the chances of success

What could be a risk of failing to change the crossing strategy when progress is not being made in CTO PCI? A) Increased chance of stent thrombosis B) Increased risk of procedure failure and complications C) Shorter procedure time D) Higher likelihood of success

B) Increased risk of procedure failure and complications

When should CTO PCI be stopped? A) When the patient expresses discomfort B) When there is a complication or excessive radiation dose C) When the operator becomes unsure of the next step D) When the CTO lesion is smaller than 10 mm

B) When there is a complication or excessive radiation dose

What radiation dose level is typically considered a threshold for stopping CTO PCI? A) >1 Gray B) >2 Gray C) >5 Gray air kerma dose D) >10 Gray

C) >5 Gray air kerma dose

Under what circumstance should CTO PCI be halted due to contrast volume? A) If contrast volume exceeds 3.7 times the estimated creatinine clearance or is too high for the patient’s baseline renal function B) If contrast volume exceeds the average for the procedure C) If the contrast injection exceeds 1 liter D) If the contrast is visible for longer than 30 minutes

A) If contrast volume exceeds 3.7 times the estimated creatinine clearance or is too high for the patient’s baseline renal function

What is a possible reason to stop CTO PCI despite ongoing efforts? A) The lesion is not responding to initial guidewire attempts B) Exhaustion of crossing options and strategies C) The patient asks for a different procedure D) The operator has a preference for non-invasive methods

B) Exhaustion of crossing options and strategies

When is it better to stop a CTO PCI procedure? A) When the physician’s preferred crossing strategy is no longer viable B) When highly aggressive strategies are likely to lead to serious complications C) When there is no visible collateral circulation D) When the lesion is too complex for stent placement

B) When highly aggressive strategies are likely to lead to serious complications

What is a common indicator for physician fatigue in CTO PCI procedures? A) The patient’s refusal to continue the procedure B) A significant increase in contrast usage C) Operator fatigue, which can hinder effective decision-making D) The lesion length exceeds 50 mm

C) Operator fatigue, which can hinder effective decision-making

When should a physician decide to stop CTO PCI for patient safety? A) If the physician is unsure about the appropriate next step in the procedure B) If progress in crossing the CTO lesion is minimal or nonexistent after extensive attempts C) When the procedure has exceeded 2 hours of total operating time D) When the guidewire breaks during the procedure

B) If progress in crossing the CTO lesion is minimal or nonexistent after extensive attempts

What should be considered when deciding to stop a CTO PCI procedure? A) The patient’s comfort and satisfaction B) The potential for further injury, complications, and radiation exposure C) The length of the CTO lesion D) The cost of the procedure

B) The potential for further injury, complications, and radiation exposure

In the case of CTO PCI failure, what is the recommended approach for the physician? A) Pursue highly aggressive strategies until success is achieved B) Stop and reassess the situation to avoid further complications C) Attempt to finish the procedure without changing the strategy D) Switch to another less invasive treatment immediately

B) Stop and reassess the situation to avoid further complications

What might indicate that the CTO PCI procedure has reached a point where it should be stopped? A) The procedure has been ongoing for over 4 hours B) The guidewire has entered the distal cap C) The procedure has failed to cross the CTO after exhausting available strategies D) The stent has been successfully deployed

C) The procedure has failed to cross the CTO after exhausting available strategies

What is critical for optimizing both short-term and long-term outcomes in CTO PCI? A) Minimizing the number of stents used B) Ensuring proper stent optimization and expansion C) Using large balloons for predilation D) Reducing the contrast volume

B) Ensuring proper stent optimization and expansion

What is typically used before stent implantation in CTO PCI to prepare the vessel? A) Balloon angioplasty only B) Predilation with appropriately sized balloons C) Stent deployment without predilation D) Coronary bypass grafting

B) Predilation with appropriately sized balloons

What imaging technique is essential before stenting in CTO PCI to assess vessel size and calcification? A) Fluoroscopy B) Intravascular ultrasound (IVUS) C) Computed tomography angiography (CTA) D) MRI

B) Intravascular ultrasound (IVUS)

Why is stenting of the distal segments of CTO vessels generally avoided? A) The distal segments are often too narrow to stent B) Stenting can lead to restenosis C) The distal segments typically enlarge over time after restoring vessel patency D) The distal segments have poor blood flow

C) The distal segments typically enlarge over time after restoring vessel patency

What should be done before stent implantation to address heavily calcified or diffusely diseased CTO vessels? A) Use plaque modification strategies such as atherectomy B) Skip predilation if the vessel is small C) Use only drug-eluting stents D) Perform coronary artery bypass graft surgery

A) Use plaque modification strategies such as atherectomy

What can intravascular imaging help with during CTO PCI? A) Measuring the cost of the procedure B) Assessing the size of the balloon C) Ensuring optimal stent expansion, apposition, and lesion coverage D) Monitoring the patient's heart rate

C) Ensuring optimal stent expansion, apposition, and lesion coverage

What is the main reason for fully expanding CTO lesions before stent implantation? A) To reduce the need for multiple stents B) To prevent stent thrombosis and restenosis C) To shorten the procedure time D) To ensure that the patient remains comfortable

B) To prevent stent thrombosis and restenosis

What is typically the role of plaque modification strategies such as atherectomy in CTO PCI? A) To prevent vessel rupture B) To help prepare the lesion for proper stent expansion C) To increase the number of stents used D) To improve the visual appearance of the vessel

B) To help prepare the lesion for proper stent expansion

Why is it essential to assess vessel calcification before stent deployment in CTO PCI? A) To determine if bypass surgery is necessary B) To assess the risk of coronary artery dissection C) To ensure that the stent will fully expand and properly appose the vessel wall D) To calculate the number of stents needed

C) To ensure that the stent will fully expand and properly appose the vessel wall

What is a potential long-term outcome that proper stent optimization can help prevent in CTO PCI? A) Coronary artery bypass grafting B) Stent thrombosis and in-stent restenosis (ISR) C) Vessel rupture D) Hemorrhage at the insertion site

B) Stent thrombosis and in-stent restenosis (ISR)

What is the average complication risk associated with CTO PCI? A) 5% B) 3% C) 1% D) 10%

B) 3%

What is a unique complication associated with CTO PCI? A) Myocardial infarction B) Perforation of septal and epicardial collaterals C) Coronary artery dissection D) Stroke

B) Perforation of septal and epicardial collaterals

What should be inserted in the CTO donor vessel to facilitate treatment if donor vessel injury occurs? A) A stent B) A safety guidewire C) A balloon catheter D) A temporary pacemaker

B) A safety guidewire

What is the target activated clotting time (ACT) for antegrade CTO PCI procedures? A) At least 250 seconds B) At least 300 seconds C) At least 350 seconds D) At least 400 seconds

B) At least 300 seconds

What is the target activated clotting time (ACT) for retrograde CTO PCI procedures? A) At least 250 seconds B) At least 300 seconds C) At least 350 seconds D) At least 400 seconds

C) At least 350 seconds

How often should the activated clotting time (ACT) be checked during a CTO PCI procedure? A) Every 15 minutes B) Every 30 minutes C) Every 60 minutes D) Once at the beginning of the procedure

B) Every 30 minutes

What complication can occur when dual injection is being used during CTO PCI? A) Balloon rupture B) Perforation of collaterals or donor vessel dissection C) Stent migration D) Arterial embolism

B) Perforation of collaterals or donor vessel dissection

What is a factor that increases the complication risk during CTO PCI? A) Simple CTO lesions B) Highly complex lesions C) Use of low penetration guidewires D) Use of retrograde only crossing technique

B) Highly complex lesions

What should be the goal ACT during an antegrade CTO PCI procedure? A) 200 seconds B) 300 seconds C) 350 seconds D) 400 seconds

B) 300 seconds

Why is it important to monitor ACT during CTO PCI? A) To prevent stent failure B) To minimize the risk of donor vessel thrombosis C) To improve guidewire movement D) To ensure proper patient sedation

B) To minimize the risk of donor vessel thrombosis

What can help reduce the risk of perforation during CTO PCI? A) Using high-frame-rate fluoroscopy B) Avoiding dual injections C) Using dual injection and orthogonal projections to assess equipment position D) Decreasing guidewire diameter

C) Using dual injection and orthogonal projections to assess equipment position

How are large vessel perforations typically treated during CTO PCI? A) With balloon angioplasty B) With stent expansion C) With covered stents D) With embolization

C) With covered stents

What is the typical treatment for distal vessel and collateral vessel perforation during CTO PCI? A) Covered stents B) Coronary artery bypass graft surgery C) Embolization D) Balloon dilation

C) Embolization

In epicardial collateral vessel perforations, how should embolization be performed? A) From one direction B) From both directions C) Using a stent D) Using high-pressure balloons

B) From both directions

What is essential for CTO PCI programs to reduce the risk of perforation and complications? A) Experience in using guidewires B) Availability and experience in using covered stents and coils C) Experience with balloon angioplasty techniques D) Expertise in retrograde approaches

B) Availability and experience in using covered stents and coils

Why is coronary perforation in prior CABG patients particularly risky during CTO PCI? A) It can cause life-threatening hematomas or bleeding in difficult-to-access areas B) It increases the risk of stent thrombosis C) It makes stent deployment more difficult D) It leads to poor vessel expansion

A) It can cause life-threatening hematomas or bleeding in difficult-to-access areas

What is one method to minimize the radiation dose during CTO PCI? A) Using high-frame-rate fluoroscopy B) Using low-frame-rate fluoroscopy and the "fluoroscopy store" function C) Minimizing the use of contrast agents D) Increasing the fluoroscopy time

B) Using low-frame-rate fluoroscopy and the "fluoroscopy store" function

When should patients who receive a high radiation dose (>5 Gray air kerma dose) during CTO PCI be followed up? A) After 1 week B) After 1 month C) To evaluate for subacute skin injury D) To assess stent patency

C) To evaluate for subacute skin injury

What is a risk associated with excessive contrast administration during CTO PCI? A) Stent migration B) Contrast nephropathy C) Coronary dissection D) Hematoma formation

B) Contrast nephropathy

How can contrast nephropathy be minimized during CTO PCI? A) By increasing the contrast volume for better visualization B) By tracking and minimizing contrast administration C) By using dual injections only D) By avoiding the use of microcatheters

B) By tracking and minimizing contrast administration