CC5&6: Introduction to intervention and PCI

Question 1

What is HAC service an example of?

Answer 1

-Primary PCI for treatment of STEMI

Question 2

In cath lab where do x rays come from?

Answer 2

-Bottom to top

Question 3

What are features of patient monitoring?

Answer 3

-12 lead ECG
-Sats
-NIBP
-Transducer set up

Question 4

What are the 2 forms of access in PCI?

Answer 4

Radial
-Post-procedure sealed with radial band

Femoral
-Closed with closure plug, stitch device, manual pressure

Question 5

Radial vs Femoral access

Answer 5

Radial
-Smaller artery makes advancing catheter more difficult
-Easier to control bleeding

Femoral
-Requires bedrest
-Puncture above bifurcation can cause retroperitoneal bleeding

Question 6

What are standard drugs in PCI?

Answer 6

Lidocaine - local anaesthetic
Verapamil - Prevents vasoconstriction/vasospasm
Heparin - Prevents thrombus
Nitrates - Vasodilation of coronary arteries

Question 7

Features of simple PCI

Answer 7

-Lesion in main vessel
-Landing zones away from branching vessels

Question 8

Key steps to simple PCI lesions

Answer 8

-Supportive guide catheter
-Good guide wire position
-Predilate lesion with balloon
-Stent lesion
-Optimise stent
-Confirm with final images successful PCI with no complications

Question 9

Diagnostic vs Guide catheters

Answer 9

Question 10

What is standard diagnostic catheter for Angiogram?

Answer 10

-Judkins catheter
-Good at obtaining images
-May be used for PCI but not supportive enough (use Amplatz and EBU instead)

Question 11

What can invasive pressure indicate about catheter position and what would effect be?

Answer 11

-Catheter angled towards wall
-Too deeply engaged
-Engaged in area of lesion
-Effect is damping or ventricularisation

Question 12

How do you know whether LAD or Circ?

Answer 12

-In LAO, LAD is on the left
-In RAO, LAD is on the right

Question 13

What is the O ring?

Answer 13

-O ring opened to add and remove angioplasty kit
-O ring causes a false pressure drop due to loss of feedback to transducer

Question 14

What are guide wires?

Answer 14

-Guide wire comes after guide catheter
-Act as a track for other PCI equipment to pass along (e.g. balloons, stent, imaging)

Question 15

Features of guide wire

Answer 15

-3cm radiopaque tip
-helps guide when positioning wire
Aims to identify:
-if guide wire has moved too distal
-selecting a small side branch
-ectopy may indicate wire irritating myocardium

Question 16

What balloon is used to pre-dilate lesion?

Answer 16

Semi-compliant balloons
-Inflated to low pressure
-Conforms to lumen size
-Indicates if lesion is compliant
-Inflated using indeflator - fluid mix of saline and contrast

Question 17

What does inflating balloon cause?

Answer 17

-Temporarily occluding flow
-Causes chest pain and ST elevation

Question 18

What is the structure of balloon catheters?

Answer 18

Monorail balloon catheter:
-Guide wire passes through balloon itself
-Exits catheter proximal to balloon

Question 19

What’s the nominal pressure?

Answer 19

-Pressure at which balloon reaches its nominal diameter (diameter on label)

Question 20

What’s the rated burst pressure?

Answer 20

-Pressure at which balloon will burst according to testing

Question 21

What’s the mean burst pressure?

Answer 21

-Mathematical mean pressure at which a balloon bursts

Question 22

What stents used to be used?

Answer 22

-Bare metal stents (BMS)
-However, high risk of restenosis

Question 23

What stents are now used?

Answer 23

Drug-eluting stents
-Slow release drug coating to prevent cell proliferation
-Preventing fibrosis and thrombus formation which could cause in-stent restenosis

Question 24

Where should stent be positioned?

Answer 24

-From normal vessel to normal vessel

Question 25

What are non-compliant balloons used for?

Answer 25

-Used to optimise stent -Ultra high strength to handle overinflation pressures to expand stents

Question 26

What is done post PCI?

Answer 26

-Remove all equipment except guide catheter -Images in two planes to confirm stent well deployed -Confirm no complications =>Stent well deployed =>Good flow to distal vessel =>No dissection

Question 27

Reasons why PCI would not be simple?

Answer 27

-Difficult to pass PCI equipment across lesion -Is the lesion significant? -Need more info about pattern of disease -Lesion does not dilate -Bifurcation lesions -Small vessel disease -In stent restenosis (ISR)

Question 28

What is guide extension?

Answer 28

-Used to provide extra support for equipment delivery in tortuous vessels -However, increased chance of damped pressure trace

Question 29

What does balloon not inflating indicate?

Answer 29

-Calcified/heavily fibrosed disease

Question 30

What are cutting balloons?

Answer 30

-Have 3 or 4 atherotomes (microsurgical blades) bonded longitudinally -Dilate to a lower pressure than NC balloons, reducing the extent of vessel wall injury

Question 31

What is rotablation?

Answer 31

-Catheter used to shave and remove the luminal calcium or fibrosis in a coronary artery

Question 32

What is shockwave balloon?

Answer 32

-Balloon which delivers electrical impulse using a sonic pressure wave to break down calcium

Question 33

What are drug-eluting balloons?

Answer 33

-Balloon coated with drug with rapid uptake and prolonged retention -30sec - 1min inflations to transfer drug to intima -Commonly used for small vessels, side branches and ISR -Inflated to low pressure to decrease chance of stenosis -Longer inflation time means chest pain and ECG changes are common

Question 34

Why are bifurcation lesions more complex?

Answer 34

-Treating one vessel's atheroma/thrombus may narrow or occlude the other vessel

Question 35

What are examples of advances in treating Chronic Total Occlusions (CTOs)?

Answer 35

-Advances in guidewire and microcatheter technology -Antegrade and Retrograde techniques

Question 36

When could restenosis occur and what makes it more likely?

Answer 36

-Gradual re-narrowing of stented segments occurs mostly between 3 and 12 months after stent placement -Caused by exaggerated neointimal formation -Increased risk in patients with high cholesterol, kidney disease, smoking and uncontrolled diabetes/hypertension

Question 37

What 2 things must we be aware of during STEMI?

Answer 37

-Reperfusion can be a high risk time for reperfusion arrhythmias -RCA - most common bradyarrhythmia -LAD - most common tachyarrhythmia -May be high thrombus burden -Consider thrombus removal device (e.g. Export catheter) -IV blood thinners (e.g. integrilin)

Question 38

What are some possible risks of PCI?

Answer 38

-Dissection/perforation of vessel -Allergic reaction to medication/contrast -Irregular heart rhythm -Infection -Bleeding at catheter insertion site -Kidney failure -Acute closure of coronary artery -Emergency coronary artery bypass graft (CABG) surgery

Question 39

Why is LIMA good choice for bypass graft?

Answer 39

-Left internal Mammary is an artery -LIMA only has to be sewn once -LIMA doesn't have valves

Question 40

What is a good option to treat vein graft stenosis

Answer 40

-CTO of native vessel -Stent in vein would likely restenose