Ablation

Question 1

attempt to modify, isolate or destroy the automatic foci or reentrant circuit

Answer 1

Ablation

Question 2

ablation is to create an electrically unexcitable area

Answer 2

scar tissue

Question 3

risks of ablation (7)

Answer 3

inadvertent complete heart block
cardiac perforation
cardiac tamponade
esophageal fistula
stroke
phrenic nerve
injury at access site

Question 4

risks of ablation %

Answer 4

2%

Question 5

produces lesion at site and causes minimal damage to surrounding tissue

Answer 5

radiofrequency (RF) ablation

Question 6

RF works by uses ___ current delivered between catheter ___ and the ____ _____

Answer 6

alternating
tip
indifferent electrode (skin patch)

Question 7

current for RF is delivered at a frequency of

Answer 7

300-750 kHz

Question 8

current is deliverved at a voltage of

Answer 8

40-60 Volts

Question 9

high frequency, low voltage results in

Answer 9

controlled thermal injury

Question 10

affects the tissue closest to the electrode tip

Answer 10

Resistive heat

Question 11

transferred from the electrode-tissue to adjacent tissue

Answer 11

conductive heat

Question 12

heat responsible for lesion size

Answer 12

conductive heating

Question 13

conventional RF catheter FR diameter and mm tip

Answer 13

7-8Fr

4mm

Question 14

power of 30 W delivered to a 4mm tip creates a lesions of depth and diameter

Answer 14

4-5mm

Question 15

New RF catheters offer tip size

produce lesion X times volume of the 4mm

Answer 15

8mm

4x the volume of the 4mm

Question 16

newer rf catheters may be used to create full thickness lesions such as

Answer 16

pectinate muscles for atrial flutter

Question 17

monitors and maintain target tissue temperature and prevents gas formation (steam) or charring at the electrode-tissue interface

Answer 17

RF generator

Question 18

irreversible thermal injury occurs when the temp of the myocardial tissue

Answer 18

48 to 50 (o) celsius

Question 19

time it takes to achieve steady state of current delivery and heat dissipation by tissue and blood

Answer 19

5 to 20 seconds

Question 20

temps >50 can cause a

100

Answer 20

steam pop or charring

Question 21

RF lesions are usually placed in the superior portions of the crista terminalis to achieve the desired result

Answer 21

SA nodal reentrant tachycardia (SANRT)

Question 22

typical atrial flutter treated by creating a series of RF lesions across

Answer 22

triscupid isthmus

Question 23

Atrial flutter creates the line of block across the slow pathway from ___ to ___

Answer 23

triscupid annulus to inferior vena cava

Question 24

reentrant, chronic or permanent AF needs to electrically divide the atria into smaller sections

Answer 24

maze procedure

Question 25

ablation of slow pathway

Answer 25

AV Nodal reentry ablation

Question 26

AVNT ablation location

Answer 26

inferior and posterior aspect of the triangle of Koch

near the CS ostium

Question 27

left sided accessory pathways

Answer 27

accessed via femoral artery across aortic valve to LV

positioned under the mitral annulus at site of pathway

Question 28

right sided accessory pathway

Answer 28

advanced through triscupid valve and positioned to obtain both atria and ventricular signals

Question 29

for VT ablation, what multipolar electrode catheters are inserted into (3)

Answer 29

RV, CS, LV

Question 30

Right bundle branch reentry (RBB) (what is done to identify and ablate)

Answer 30

ablation catheter records HIS EGM and then advanced till a RBB is shown

Question 31

RVOT tachycardia (induction)

Answer 31

induced with isoproternol

Question 32

idiopathic LV tachycardia (ILVT)

Answer 32

mapping performed at LV

earliest site of activation, LV deflection is preceded by distinct fascucular potential that resembles a HIS potential