9/14/2019

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Ablation of Persistent AF: What to do Beyond PV Isolation

Aman Chugh, MDSeptember 13, 2019

CHRSSan Francisco, CA

Disclosures

• Biosense-Webster – research support

• Boston Scientific – research support

• Abbott– Fellows education course

Outline

• Pathophysiologic differences b/w paroxysmal (PAF) and persistent (Ps) AF

• Evidence for mapping and ablation outside the PVs in patients with Ps and longstanding (LS) Ps AF

• Present an intuitive, evidenced-based approach to catheter ablation of Ps AF

Permanent AF

Increasing AF

No AF

Platonov JACC 2011

Fibrosis and fatty infiltration correlated w/ lymphocyte infiltration (ie, inflammation)Fibrosis – cause or consequence of AF?

PAFPs AF

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2

0

5000

10000

15000

20000

25000

30000

1LAA

2Base

3Ridge

4LtAntrum

5RtAntrum

6Anterior

7Posterior

8Roof 9

9aMI

9bInferior

9cCS

p

c

‡ ‡

§

§

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¶

¶ ¶

ap

pe

nd

age

ba

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left

PV

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rig

ht P

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LA regions

Paroxysmal

Persistent

0.75

1.50

2.25

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plit

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e (

mV

)

NS

† †

Structural differences b/w Ps and PAF

Yoshida…Chugh Heart Rhythm 2010

5.5

5.6

5.7

5.8

5.9

6

6.1

6.2

6.3

6.4

Paroxysmal AF Persistent AF

DF

(H

z)

Paroxysmal AF

Persistent AF

P=0.0006

Electrical remodeling – faster drivers

Paroxysmal AF

(N=18)

Persistent AF

(N=40)

P

Age 58±8 59±10 0.71

Gender (M/F) 14/5 33/7 0.44

Body mass index (kg/m2) 27±3 32±5 0.0001

Sleep apnea syndrome 3 (17%) 7 (18%) 0.94

Hypertension 6 (32%) 25 (63%) 0.03

Diabetes 1 (6%) 2 (5%) 0.93

Period from the first diagnosis of

AF (month)

54±38 53±47 0.96

Duration of continuous AF (month) N/A 26±19 -

LA pressure (mmHg) 10±4 18±5 <0.0001

LA diameter (mm) 38±4 48±6 <0.0001

LA volume indexed (ml/m2) 43±10 68±20 <0.0001

Ejection Fraction (%) 64±7 (during

SR)

58±7 (during

AF)

-

Yoshida…Chugh HR 2010

Ghanbari et al HR 2014

Is PAF really different from Ps AF?

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3

0 3 6 9 12 15 18 21 24 27 30 33 36 39

Months

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Cu

mu

lati

ve P

rop

ort

ion

Fre

e f

rom

AF

Freedom from Recurrent AF after PV Isolation

Paroxysmal AF (234)

Persistent AF (20)

P<0.001

Oral et al Circ 2001

Cu

mu

lati

ve P

rop

ort

ion

Fre

e f

rom

AF

Longstanding Ps AF - PVI alone was able to

establish long-term SR in only 24% (49 of 202)

Tilz et al JACC 2012

Sanders et al JCE 2006

ms ms

Ps AF – no Δ in global AF CL with PVI PAF – progressive increase in AF CL with PVI

DF of PVs: 8.8 HzDF of LA: 6.9 Hz

∇ : 1.9 Hz

DF of PVs: 11 HzDF of LA: 5.8 Hz

∇ : 6.2 Hz

Why aren’t PVs enough in persistent AF?

PV-LA gradient (∇ )STAR AF 2: PV isolation is all you need for Ps AF?

Verma NEJM 2015

With or without AAD

PVs alone – 41% after one procedure

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STAR AF 2

Takeaways

• Unproven adjuncts

– automated “CFAE” algorithms – “lack of pathophysiologic

relevance” (Lau et al HR 2015)

• Ambiguous endpoints (linear ablation/procedural)

• If AF →AT, cardioverted at operator discretion

• Did additional ablation do anything to AF?

– Was AF slowed? If not, targets were not identified

• Excellent single center results not reproducible

• 20% of patients presented in sinus rhythm – how

applicable to patients presenting in AF? * ** **

180250

Septal LAd

II

Septal LAp

Septal RA

180 80?

CS

V1

LA

180

LAd

V1

RFA

Continuous electrical activity - specific but uncommon

Most ”CFAEs” are generated by far-field activity (Narayan et al HR 2010)

Our eyes are appear to be better than algorithms in ascertaining FF EGMs/local activation rates

@ inferior LA

Linear block across mitral isthmus? s/p endo/epi (CS) RFA and EtOH VOM

CS3-4

CS5-6

CS1-2

CS7-8

Abld

Ablp

V1

CS9-10

S

RidgeLAA

S

145

S S

Ridge – RFA endo MI

180

Avoid mitral isthmus

O.K., So what then

• Approach must be

– Evidenced-based – proven

– Unambiguous

– Intuitive

– Practical, with conventionally available tools

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Case

• 50 yo man with LS Ps AF since 2013

• AVR for congenital AS

• CV – SR for seconds

• Ef 35% and CHF

• RFA on 1/2015

– PVI for rapid PV tachycardia

– AF persists

CSd

CSp

Abld

V1

RAA

RFA @ low posterior LA

Last f/u 2/2019–SR without AADEf 50%

CSd

CSp

Abld

V1

RAA

AF terminates to SR

What’s next after PVI?

Posterior Wall Isolationprovenunambiguousprevents roof dependent atrial flutter

(Heart Rhythm 2016;13:132–140)

Bai et al

Conclusions – “ePVAI+LAPW is still associated with a significant high incidence of very late recurrence of atrial tachyarrhythmia.”

Abld

V1

LAA

CSd

V1

Abld

PV

LIPV

Abld

Ablp

V1

Case

• DK

BaselineLAA CL 178

LAA<LIPV

AF Persists despite PVI

OK, LA is driver but how to target? PVs/Posterior LA – out; CS – slow→ LAA driver

CS

LAA

V1

RAA

Post PVI/PWILAA=162 ms

RAA=200 ms

∇

V1

RAA

CSd

CSp

* AF terminates to AT during RFA around LAA

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V1

II

aVF

CSd

CSp

V1

Abld

Ablp

ECG – AT 240

RFA at posterior RA, Eustachian ridge, and finallyat CTI terminates AT

Endpoint of LAA RFA – AF terminationSR without AAD for 4 years

Case

• 52 yo man with permanent AF since 2013

• DC CV 1995

• PVI 2010 at OSH – PV stenosis

• “Mini-maze” 2013

• Worsening effort intolerance

• RFA 11/2018

Posterior LA

LAA 137

V1

CS

LA

LA

V1

CS

LA

LA

V1

CS

LAA

LAA

Septum–slow activity

640

150

V1

CS

LAA

LAA

LAA

After extensive ablation around LAA, entrance block into LAA

Endpoint of LAA RFA – slowing of conduction into LAALAA no longer driving AFLAA as driver – proven and unambiguous*

LAA

RAA

CSd

CSp

178

161

III

V1

∇

Case-

• 54 yo man Ps AF

• AF persists post PVI, PWI, LAA RFA

• RA to LA gradient

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Where to ablate in RA? SVC?

AF termination sites in RA

Hocini et al JACC 2010

RAA

V1

RAA

SVC

SVC288 ms

179 ms

• 90 patients Ps AF

• 26 (29%) required RA ablation

• RA targets: RAA, lateral RA, lateral TA, RA roof

• Follow up of 21±18 months

– 53 of the 64 patients in the LA only group (83%)

– 20 of the 26 patients in the RA group (77%) in SR w/o AAD (p=0.57)

Ghannam…Chugh HRS 2014

Lateral RAAbase

CSd

CSp

V1

50 ms

Extremely fast bursts from RAA (20 Hz!)

AF terminates to AT after RFA at RAA

*CSd

CSp

V1

Abld

CSd

CSp

V1

Abld

Ablp

Termination w/o global capture @ MILinear block achieved

RAA driver – intuitive, evidence-based

SR w/o AAD for 6 yrs

230 230

S S S S

230

LAA

RAA

SVC

Tricuspid

valve

CS

LPV

Cut-Sew Maze

Anatomically based

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CASE

• 76 yo woman with persistent AF since 2013

• Recurrence despite cardioversion and propafenone

• s/p stenting of RCA

• RFA 10/2015

CSd

CSp

V1

III

LIP

V

Right PVs isolated

AF terminates to SR during RFA of L PVs

What would you do next?A. Linear ablation at LA roofB. Linear ablation at mitral isthmusC. Nothing moreD. Linear ablation at CTI

Noninducible with isoproterenol and rapid pacing

SR w/o AAD x 4 years

Procedural details

• Persistent AF - 2-3 procedures

• RF duration 60-80 minutes

• If AF terminates to AT, map and ablate

• Procedure time 4-5 hours

• AT/”atypical atrial flutter” is unavoidable in most patients

• If AF recurs after first procedure – Likely RA ablation (30% of patients)

• Emphasis on AF termination during 2nd procedure

• 80% without antiarrhythmic medications

• Complications 1%

• No perforation during LAA/RAA RFA

• Secondary prevention measures

Summary

• Ps and LS Ps AF – more structural and electrical alterations cf. PAF

– Calls for a measured, more aggressive approach than PVs

• Mapping during AF – identification of drivers; not possible during SR

• Tailored to patient

– if AF terminates with PVI – no reason to do more

– If AF terminates during LAA RFA, don’t need to isolate LAA

• ATs are unavoidable in most if we wish to get rid of AF

• Whichever approach →must show that fibrillatory process was affected – was AF slowed or terminated?