**1. Introduction**

For daily planned procedures, there are several approaches for coronary interventions. In reality and especially an emergency situation, any kind of arterial approach that can reach the coronary tree can be used as long as emergency percutaneous coronary interventions could be successfully and safely performed.

These common approaches include radial right and left, ulnar right and left, distal radial right and left, femoral, and brachial. Carotid, axillary approaches might be necessary in the right clinical presentation. For each approach, operators need to be familiar with the limitations, advantages, disadvantages, access and closure techniques, potential complications, and their management. Knowledge of arterial and venous anatomy and its possible anomalies are basic requirements of any vascular operator.

This chapter is focusing on PCI technical aspects and high-risk interventions. Reader is redirected to other resources that focus on performing diagnostic left

heart catheterization (LHC) as it is crucial to understand everything about diagnostic catheters, procedure, and equipment before proceeding with PCI.

**Table 1** includes a required checklist of equipment needed in any catheterization lab performing PCI, especially high-risk PCI.

Sheaths 6–8 French standard (short and supportive long 23, 45, 65 cm for support

Sheathless 7Fr system like RailWay system Injection system Manifold 4 valve system or Acist device. At least Manifold should be

Guide catheters Multiple available guide catheters available from different companies and

Guide wires Vascular wires and catheters: 0.035 or 0.038 J tip wire, wholey wire, glide

See **Table 3** for list of available micro catheters

Small balloons, over the wire or rapid exchange

CrossBoss Catheter/Stingray LP balloon and wire

Bare metal stents, drug eluting stents and Covered stents

Vascular coils: better if detachable and 0.014 compatible such as Axium coils. Other 0.018 pushable coils could be used if there are the only available ones but they require higher profile micro catheters like Progreat

Atherectomy systems (rotational, orbital)

Balloons and stents Compliant and noncompliant balloons of all different sizes and lengths,

Covered stents (Graftmaster or PK Papyrus)

Snares: Esnare or Atrieve 18–30 mm or 27–45 mm

Vascular balloons and stents for vascular access complications

Pericardiocentesis tray, echo contrast Echocardiogram probe and vascular probe

glide straight and angled tip catheters

Regular Tuohy, Co-pilot, or Guardian

IKARI left, Voda right, Amplatz left

CLS, SAL, Amplatz left etc.

Tornus or Turnpike Gold

cutting balloons, Ostial Flash

Guide catheter extensions Guideliner, Guidezilla, Guidion, Trapliner

IVUS, OCT

Threader LASER

or Renegade

Thrombin

Hemodynamics support Impella 2,5, CP, Impella RP, IABP and VA ECMO

commonly used

available

Y-connector with hemostatic valve

*Coronary Artery Intervention Techniques DOI: http://dx.doi.org/10.5772/intechopen.93458*

Intravascular diagnostic

Micro-catheters/support

imaging

catheters

Lesion crossing/ preparation for stenting

Dissection/reentry equipment

Complications management

Radiation protection

*Necessary equipment for successful PCI program.*

**Table 1.**

**207**

available: pinnacle, bright tip, braided and destinations

of a tortuous, iliac and aorta for femoral approach). Multiple sheaths

for right and left system; differences are minimal. Starting from less support to maximum support. More support is provided with contralateral support guide catheters against the contralateral aortic wall or aortic valve For the right: Judkins right 4, IMA, Amplatz right, Multipurpose, KR4,

For the left system: Judkins left, IKAR left, Kimny, Voda left, EBU, XB,

wire, glide wire advantage wire, super stiff or extra stiff wire (help advance sheath through scar tissue and straighten tortuous large vessels),

For coronary wires: see **Table 2** for list of available wires

Radial sheaths 6–7 French; several available sheaths: slender sheath most

## **2. Percutaneous coronary interventions**

Performing successful PCI requires good planning. Access site, anticoagulation, antiplatelet therapy, good assessment of target lesions, intravascular imaging, adjunct therapies (i.e. atherectomy or other plaque modification procedures), and instruments necessary to perform the procedure and handle complications should be available.

The main simple steps for any PCI are engaging the target system with the guide catheter, wiring the lesion, preparing the lesion for stenting and finally deploying the stent. Every step can be a challenge by itself.

#### **2.1 Radial approach**

Over the last two decades, radial approach for coronary interventions has developed significantly. It has become the standard of care in any catheterization lab.

In addition to growing evidence that supports this approach of safety and better outcome in coronary interventions [1–4], it is also significantly evolving as a great approach for peripheral arterial interventions, including abdominal vessel interventions and even lower extremity interventions.

With obesity pandemic, operators need to perform LHC/PCI using a radial approach and avoid femoral at all prices, and we will discuss the femoral approach in obese patients. Obese patients can be very challenging patients for radial approach, but it is definitely worth it to avoid using femoral approach and dealing with access and potential complications that rise especially in obese diabetic patients [5].

For our topic of coronary interventions, radial approach especially right radial approach is the main approach for any patient; first time coronary angiogram and PCI patients or returning patients, chronic total obstruction interventions and even patients with prior CABG [6].

In case of suspected acute stent thrombosis after completing PCI, radial access at the same site can be safely performed. While in femoral approach, it depends on the closure device that has been used.

It has proven that it is safer than any other approach with less bleeding, access complications, and outcome at least in STEMI patients [3].

Even in post-CABG patients, right radial approach can be used effectively. All aortic grafts can be imaged easily. Even the left internal mammillary artery LIMA can be reached but requires manipulating across the aortic arch to reach left subclavian and wiring it. Meaning crossing all the head vessel which in diseased aortic arch might not be a smart idea as it could increase risk of emboli ischemic stroke significantly. That is where left radial approach comes handy.

In elderly small size females, radial approach for LHC/PCI is a priority as this category of patients carries the highest risk of vascular complications and bleeding using femoral approach. 5Fr radial sheath is considered in general safer to perform LHC and even simple PCI that does not require 6F guide catheters.

## *Coronary Artery Intervention Techniques DOI: http://dx.doi.org/10.5772/intechopen.93458*

heart catheterization (LHC) as it is crucial to understand everything about diagnostic catheters, procedure, and equipment before proceeding with PCI.

lab performing PCI, especially high-risk PCI.

**2. Percutaneous coronary interventions**

the stent. Every step can be a challenge by itself.

ventions and even lower extremity interventions.

complications, and outcome at least in STEMI patients [3].

significantly. That is where left radial approach comes handy.

LHC and even simple PCI that does not require 6F guide catheters.

be available.

patients [5].

**206**

patients with prior CABG [6].

closure device that has been used.

**2.1 Radial approach**

**Table 1** includes a required checklist of equipment needed in any catheterization

*Cardiac Diseases - Novel Aspects of Cardiac Risk, Cardiorenal Pathology and Cardiac Interventions*

Performing successful PCI requires good planning. Access site, anticoagulation,

The main simple steps for any PCI are engaging the target system with the guide catheter, wiring the lesion, preparing the lesion for stenting and finally deploying

Over the last two decades, radial approach for coronary interventions has developed significantly. It has become the standard of care in any catheterization lab. In addition to growing evidence that supports this approach of safety and better outcome in coronary interventions [1–4], it is also significantly evolving as a great approach for peripheral arterial interventions, including abdominal vessel inter-

With obesity pandemic, operators need to perform LHC/PCI using a radial approach and avoid femoral at all prices, and we will discuss the femoral approach in obese patients. Obese patients can be very challenging patients for radial approach, but it is definitely worth it to avoid using femoral approach and dealing with access and potential complications that rise especially in obese diabetic

For our topic of coronary interventions, radial approach especially right radial approach is the main approach for any patient; first time coronary angiogram and PCI patients or returning patients, chronic total obstruction interventions and even

In case of suspected acute stent thrombosis after completing PCI, radial access at the same site can be safely performed. While in femoral approach, it depends on the

It has proven that it is safer than any other approach with less bleeding, access

Even in post-CABG patients, right radial approach can be used effectively. All aortic grafts can be imaged easily. Even the left internal mammillary artery LIMA can be reached but requires manipulating across the aortic arch to reach left subclavian and wiring it. Meaning crossing all the head vessel which in diseased aortic arch might not be a smart idea as it could increase risk of emboli ischemic stroke

In elderly small size females, radial approach for LHC/PCI is a priority as this category of patients carries the highest risk of vascular complications and bleeding using femoral approach. 5Fr radial sheath is considered in general safer to perform

antiplatelet therapy, good assessment of target lesions, intravascular imaging, adjunct therapies (i.e. atherectomy or other plaque modification procedures), and instruments necessary to perform the procedure and handle complications should


#### **Table 1.**

*Necessary equipment for successful PCI program.*

In chronic total occlusion (CTO) interventions, radial approach can be used as a single access in antegrade approach or in retrograde approach with another access that could be femoral or even left radial depending on the clinical scenario.

Radial approach is very convenient for patients, allowing them to move as soon as possible and avoid prolonged bed rest and recurrent need for applying pressure in case of recurrent bleeding.

Initially, radial approach had increased radiation exposure and time compared to femoral approach. As it has a learning curve, this is not true anymore due to increase in operators' experience. Still, left radial approach has more operator radiation compared to femoral and right radial but less complications compared to femoral approach [7–9]. Using appropriate radiation protection could decrease operator's radiation exposure [10].

As in any artery, radial artery can dilate, but the dilation ratio depends on the baseline size, presence of atherosclerosis disease, and calcifications. Complications can occur when inappropriate dilation is performed. Specific medication mix is used to avoid spasm of radial or ulnar artery after getting access and sheath inserted. Still, some patients have significant spasm which can make radial approach very hard and even impossible to complete the requiring switching to femoral approach.

When facing any resistance advancing the wire, operator should perform an angiogram especially if 7F system is planned.

Sheath-less technique is encouraged when using larger than 6 F. 7Fr and can be performed in most patients. 8F requires large radial artery. Female patients with small size and short status are more likely to not have a radial vessel that accommodates larger than 6Fr system.

specific characteristics and success rate of intervention (**Tables 5** and **6**), Systemic evaluation of coronary lesion and understanding of the anatomical and physiologi-

**Type 2** Long diffuse and smooth narrowing of the body or distal end of the vessel

Severity Minimal Mild Moderate Severe Intimal thickness <0.3 mm <0.3 mm 0.3–0.5 mm >1 mm Or Or Or Extent of plaque <180 >180 >0.5 mm, <180 >0.5 mm, >180

**Class I Class II Class III Class IV**

Syntax score is an additional tool that was developed to stratify patients based on the complexity of their coronary artery disease (CAD) and identify patients who benefit from different revascularizations options (CABG and PCI) based on their score. Similar to ACC/AHA classification of lesions, Syntax score is calculated based on each lesion characteristics with more details (**Figure 1** and **Table 7**). It is another available tool to evaluate the risk of lesions and subsequently the outcome of

cal characteristics for each lesion are essential for successful intervention.

Discrete <10 mm length Little or no calcification Concentric Less than total occlusion Readily accessible Not ostial location

Smooth contour Absence of thrombus

Tubular 10–20 mm length Ostial in location

Moderate tortuosity of proximal segment Some thrombus

**Type B lesions: moderate success 60–85%: moderate risk**

*ACC/AHA classification of coronary lesions and outcome predictors.*

**Type C lesions: low success <60%; high risk**

None-angulated segment <45° No major branch involvement

Moderately angulated 45–90° Total occlusion <3 months old Irregular contour Moderate to heavy calcifications

Excessive tortuosity of proximal segment Total occlusion >3 months old Extremely angulated segment >90° Inability to protect side branch

Eccentric Bifurcation lesions requiring double guidewires

Diffuse lesion >20 mm length Degenerated venous graft with friable lesions

**Type 1** Multiple radiolucent lumen

*Duke classification of cardiac allograft vasculopathy on IVUS.*

*Coronary Artery Intervention Techniques DOI: http://dx.doi.org/10.5772/intechopen.93458*

**Type 3** Focal or tubular stenosis

*Classification of spontaneous coronary artery dissection.*

**Type A lesions: high success rate > 85%; low risk**

procedure.

**Table 5.**

**209**

**Table 4.**

**Table 3.**

Ulnar artery can be dominant or the same size and can be used for PCI easily and safely. There is no significant data to compare radial and ulnar approaches.

#### **2.2 Understanding coronary artery lesions**

Atherosclerosis is the most common etiology for coronary artery disease. However, operator should understand the difference in physiology and invasive management of other etiologies such in inflammatory post-transplant vasculopathy (Cardiac Allograft Vasculopathy CAV) (**Tables 2** and **3**), vasculitis, aneurysms, and spontaneous coronary artery dissections (**Table 4**). Although the main principles of interventions are similar, these special etiologies require special considerations.

National American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions ACC/AHA/SCAI and international societies of cardiovascular diseases European Society of Cardiology ESC have their classifications of lesions risk of interventions for each coronary lesion based on


#### **Table 2.**

*Types of cardiac allograft vasculopathy lesions.*

### *Coronary Artery Intervention Techniques DOI: http://dx.doi.org/10.5772/intechopen.93458*


**Table 3.**

In chronic total occlusion (CTO) interventions, radial approach can be used as a single access in antegrade approach or in retrograde approach with another access that could be femoral or even left radial depending on the clinical scenario.

*Cardiac Diseases - Novel Aspects of Cardiac Risk, Cardiorenal Pathology and Cardiac Interventions*

Radial approach is very convenient for patients, allowing them to move as soon as possible and avoid prolonged bed rest and recurrent need for applying pressure

Initially, radial approach had increased radiation exposure and time compared to

As in any artery, radial artery can dilate, but the dilation ratio depends on the baseline size, presence of atherosclerosis disease, and calcifications. Complications can occur when inappropriate dilation is performed. Specific medication mix is used to avoid spasm of radial or ulnar artery after getting access and sheath inserted. Still, some patients have significant spasm which can make radial approach very hard and even impossible to complete the requiring switching to femoral approach. When facing any resistance advancing the wire, operator should perform an

Sheath-less technique is encouraged when using larger than 6 F. 7Fr and can be performed in most patients. 8F requires large radial artery. Female patients with

Ulnar artery can be dominant or the same size and can be used for PCI easily and

Atherosclerosis is the most common etiology for coronary artery disease. However, operator should understand the difference in physiology and invasive management of other etiologies such in inflammatory post-transplant vasculopathy (Cardiac Allograft Vasculopathy CAV) (**Tables 2** and **3**), vasculitis, aneurysms, and spontaneous coronary artery dissections (**Table 4**). Although the main principles of interventions are similar, these special etiologies require special considerations. National American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions ACC/AHA/SCAI and international societies of cardiovascular diseases European Society of Cardiology ESC have their classifications of lesions risk of interventions for each coronary lesion based on

small size and short status are more likely to not have a radial vessel that

safely. There is no significant data to compare radial and ulnar approaches.

femoral approach. As it has a learning curve, this is not true anymore due to increase in operators' experience. Still, left radial approach has more operator radiation compared to femoral and right radial but less complications compared to femoral approach [7–9]. Using appropriate radiation protection could decrease

in case of recurrent bleeding.

operator's radiation exposure [10].

angiogram especially if 7F system is planned.

**2.2 Understanding coronary artery lesions**

Type A Discrete, tubular, or multiple stenosis

Type B1 Abrupt onset with distal diffuse concentric narrowing and obliterated vessels

Type B2 Gradual, concentric tapering with distal portion having some residual lumen Type C Narrowed irregular distal branches with

squared off, ending abruptly

*Types of cardiac allograft vasculopathy lesions.*

**Table 2.**

**208**

terminations that are often none-tapered and

accommodates larger than 6Fr system.

*Duke classification of cardiac allograft vasculopathy on IVUS.*


#### **Table 4.**

*Classification of spontaneous coronary artery dissection.*

specific characteristics and success rate of intervention (**Tables 5** and **6**), Systemic evaluation of coronary lesion and understanding of the anatomical and physiological characteristics for each lesion are essential for successful intervention.

Syntax score is an additional tool that was developed to stratify patients based on the complexity of their coronary artery disease (CAD) and identify patients who benefit from different revascularizations options (CABG and PCI) based on their score. Similar to ACC/AHA classification of lesions, Syntax score is calculated based on each lesion characteristics with more details (**Figure 1** and **Table 7**). It is another available tool to evaluate the risk of lesions and subsequently the outcome of procedure.


### **Table 5.**

*ACC/AHA classification of coronary lesions and outcome predictors.*


#### **Table 6.**

*SCAI classification of coronary lesions.*

Bifurcation lesions are one of the most challenging lesions for intervention. Multiple classifications have been developed with Medina being the most used one (**Figure 2**).

All classifications are meant to help operator to address the risk of intervention, success rate, potential complications and outcome. Operator should always keep in mind that coronary angiograms are only two dimensional images of three dimensional lesions. Baseline orthogonal and multiple projections angiogram should be used as possible to help achieve best angiographic results.

Deciding the need for hemodynamic support is not only related to the lesion characteristics. It is also based on the whole picture of the patient presentation, coronary and peripheral anatomy, comorbidities and evidence-based outcome. In some cases, the decision is clear whether to use hemodynamic mechanical support or not but in most of the cases, the answer is not clear.

Available mechanical hemodynamic support devices (left ventricular assist device LVAD) are intra-aortic balloon pump IABP, Impella (which comes in different sizes depending on the cardiac output they provide Impella 2.5, Impella CP, Impella 5), RP Impella (right ventricular Impella), venous arterial Extracorporeal membrane oxygenation (ECMO) (which also can provide different cardiac output depending on cannula size but also provide oxygenation which Impella does not) and Tandem heart. The discussion of each device indications, advantage and disadvantages is beyond this chapter.

The timing of hemodynamic support in acute setting (not planned PCI) before or after restoration of coronary flow is controversial and depends on several

cofounders such as the presence of cardiogenic shock and the expected time to restore coronary flow in challenging lesions. Ongoing clinical trial are trying to address these questions. So far, there is no strong data to support placement

*Syntax score: top shows the dominance and numbering of coronaries segments, bottom: characteristics of each*

**Figure 1.**

*Coronary Artery Intervention Techniques DOI: http://dx.doi.org/10.5772/intechopen.93458*

*segment.*

**211**

*Coronary Artery Intervention Techniques DOI: http://dx.doi.org/10.5772/intechopen.93458*

#### **Figure 1.**

Bifurcation lesions are one of the most challenging lesions for intervention. Multiple classifications have been developed with Medina being the most used one

*Cardiac Diseases - Novel Aspects of Cardiac Risk, Cardiorenal Pathology and Cardiac Interventions*

used as possible to help achieve best angiographic results.

**SCAI Type I: highest success rate and lowest risk** Does not meet the criteria for ACC/AHA type C lesion

Does not meet the criteria for ACC/AHA type C lesion

And occluded OR occluded more than 3 months alone

or not but in most of the cases, the answer is not clear.

vantages is beyond this chapter.

All classifications are meant to help operator to address the risk of intervention, success rate, potential complications and outcome. Operator should always keep in mind that coronary angiograms are only two dimensional images of three dimensional lesions. Baseline orthogonal and multiple projections angiogram should be

Deciding the need for hemodynamic support is not only related to the lesion characteristics. It is also based on the whole picture of the patient presentation, coronary and peripheral anatomy, comorbidities and evidence-based outcome. In some cases, the decision is clear whether to use hemodynamic mechanical support

Available mechanical hemodynamic support devices (left ventricular assist device LVAD) are intra-aortic balloon pump IABP, Impella (which comes in different sizes depending on the cardiac output they provide Impella 2.5, Impella CP, Impella 5), RP Impella (right ventricular Impella), venous arterial Extracorporeal membrane oxygenation (ECMO) (which also can provide different cardiac output depending on cannula size but also provide oxygenation which Impella does not) and Tandem heart. The discussion of each device indications, advantage and disad-

The timing of hemodynamic support in acute setting (not planned PCI) before

or after restoration of coronary flow is controversial and depends on several

(**Figure 2**).

**210**

**Table 6.**

Patent

Patent

Occluded

**SCAI Type II lesion**

**SCAI Type III lesion**

**SCAI Type IV lesion**

Diffuse lesion >20 mm length

*SCAI classification of coronary lesions.*

Excessive tortuosity of proximal segment Extremely angulated segment >90° Inability to protect major side branch Degenerated venous graft with friable lesions

Diffuse lesion >20 mm length

Excessive tortuosity of proximal segment Extremely angulated segment >90° Inability to protect major side branch Degenerated venous graft with friable lesions

*Syntax score: top shows the dominance and numbering of coronaries segments, bottom: characteristics of each segment.*

cofounders such as the presence of cardiogenic shock and the expected time to restore coronary flow in challenging lesions. Ongoing clinical trial are trying to address these questions. So far, there is no strong data to support placement
