ablation of persistent af - osu center for continuing ... 1 steven j. kalbfleisch, md medical...
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10/26/2017
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Steven J. Kalbfleisch, MDMedical Director Electrophysiology LaboratoryOhio State University Wexner Medical Center
Ross Heart Hospital Columbus, Ohio
Ablation of persistent AFIs it different than paroxysmal?
SPEAKER DISCLOSURE• Financial support as follows:
– Research / fellowship funding support from St Jude Medical, Medtronic, Boston Scientific, Biosense Webster and Biotronik
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Paroxysmal(Self-terminating)
First Detected
Permanent
Classification of Atrial FibrillationACC/AHA/ESC Guidelines
Persistent(Not self-terminating)
Is this the right way to divide the AF population?
Cycle of Change with AF
PV Anatomy and Cellular Physiology - Spontaneous Rapid Depolarizations…..Initiates AFib
Rapid Atrial Rates Result in Intracellular Calcium Overload
Calcium Overload - Breakdown of Intracellular Structure / Mitochondria & Surface Proteins
Atrial Myopathy and Intra-myocardial Fibrosis and Scarring – Conduction Slowing
HTN, OSA, Pulmonary Dz, Valve
Aging,DM,
MI, Valve
Facilitates Further AFib
PAF onset
AF Begets
AF
What we do know
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Triggers Substrates
Initiation Maintenance
ParoxysmalPersistent
Permanent
Triggers vs SubstrateSpectrum of AF
Is this a continuum or are PAF and PerAF different entities?
Cardioversion of PerAF
•Duration of AF is the best predictor of recurrent AF
Dittrich HC. Am J Cardiol. 1989
< 3 Months3 - 12 Months> 12 Months
100
80
60
40
20
0Initial One month
post-CVSix months
post-CV*P = <0.02
Pat
ien
ts i
n s
inu
s rh
yth
m (
%)
Length of timein AF prior tocardioversion
*
What we have known for a long time
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There is significant overlap in the documented AF burden between
patients categorized as PAF vs PerAF
Charitos et al, JACC 2014
Is our current classification scheme appropriate?
Dixit et al, Heart rhythm 2008
103 pt (70% PAF, 30% PerAF)Randomized to all PVI – ALL (51) vs PVI – Arrhythmogenic (52)
Distribution of arrhythmogenic PVs was the same for both PAF and PerAF(< 2 veins in 29%, 3 veins in 40% and 4 veins in 31%)Indicating that PAF and PerAF have the same basic PV triggering mechanism
However PerAF was a predictor of late recurrence (57% NSR @ 1 yr)
Do PerAFand PAF have the same basic triggering mechanism?
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Marrouche et al, JAMA 2014
15 centers / 6 countries, 329 patients referred for 1st AF ablationPAF 168 (65%), PerAF 75 (29%), Perm / LS PerAF 17 (6%)
Pattern of AF was not a good predictor of the degree of fibrosisDegree of fibrosis was strongly associated with AF recurrence
Is the substrate the same for PerAF and PAF?
Ablation Results
PAF vs PerAFSame or different?
• PAF patients can progress to PerAF and has similar triggers (same basic process)
• Some PAF and PerAF Pts can have similar AF burden during long term monitoring
• CMR fibrosis grading has shown significant overlap between PAF and PerAF
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Callans. Circulation. 2008
Three Randomized TrialsRFA vs AA Drugs
100 –
90 –
80 –
70 –
60 –
50 –
40 –
30 –
20 –
10 –
0 –
Freedomfrom
RecurrentAF(%)
Ablation
A4(n = 112)
APAF(n = 198)
CACAF(n = 137)
Paroxysmal Persistent
Arranged according to Duration of AF
Drug
Lim et al, JACC clinical electrophysiology, 2016
129 Persistent AF patients from onset (PsAFonset) vs231 PsAF patients which had transitioned from PAF
Mean # procedures = 1.4
PsAF onset patients
Not all Persistent AF is the same
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PAF vs PerAFSame or different?
• Single procedure AF control is better for PAF (70-80%) than PerAF (40-50%)
• PerAF is more heterogonous groupthan PAF (Short term vs Long standing PerAF vs PerAF from onset)
• Bottom line – the pattern of AF is important but doesn’t tell the whole story
EP Physician vs Persistent AF
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212 patients – 48% PAF, 52% Per or LS PerAF
No difference in outcomes between PAF and Per / LS PerAFIndicates that the LAA and RA may be important for ablating PerAF
Weimar et al, Circ A+E, 2012
A more extensive ablationNon-PV rotor /driver on posterior wall
The question is how to find that spot in everyone
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Early Rumors(20 hr cases)
2016
Mid 90’s
Right Sided Linear
Phrenic Nerve Injury
Left Sided Focal
Tamponade
TIA/CVA
PV Isolation
PV Stenosis
WACA + Linear
Esophageal Fistulas
Left Atrial Flutters
Phrenic NerveInjury
Back to the Right Side
?Need for Topera orEpicardial / Hybrid approaches
Atrial Fibrillation AblationEvolution of a Moving Target
Can’t we just throw technology at the problem?
IVUS / Tran-septal Lasso 3D Mapping Cryo-ablation Stereotaxis
Rotors
Is it a mapping issue, lesion set issue, energy source issue …?
Strategies for Ablation of PerAF
1. PVI (WACA) alone (Like what we do for PAF)
2. PVI + Additional Trigger Mapping
3. PVI + CFAE (or CFAE alone)
4. PVI + linear lesionsRoof, Mitral Isthmus, Box lesion set, LAA isolation
5. Stepwise approach / Frequency gradientsAF termination endpoint
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Lin et al, JCE 2012
Note: Only 15/130 (11%) had non-PVTAs identified
Oral et al, 2008
CFAE = CL < 120ms, CL < AF CL in CS, fractionated egms or CEA
What is a CFAE?
Is PerAF a Biatrial Disease?
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Oral et al, 2008
LA / CS CFAEs
Termination of AF during LA CFAE ablation is a good prognostic signRA CFAE ablation did not provide additional benefit
Dixit et al, 2012
156 patients randomized to 3 different RFA arms, 1 yr F/UMean AF duration = 47 + 50 mths
Arm 1 = 55 ptsPVI + Identified Non-PV triggers
Arm 2 = 50 ptsPVI + emperic Non-PV trigger
Sites
LA
RA
Arm 3 = 51 ptsPVI + LA CFAEs
Automated CFAE algorithm
Triggers vs Substrate
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Dixit et al, 2012
Conclusion: Triggers are more important than substrate or CFAEs are the wrong substrate to target
Stepwise AF AblationAblation to termination
O’Neill et al, J interventional Card Electrophysiology, 2006
Average case time > 4 hours, low termination rate to NSR
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Brooks et al, Heart Rhythm 2010
STAR AF II, NEJM 2015
PVI Alone59%
PVI + CAFÉ49%
PVI + Linear46%
NSR @ 18mths
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What’s “New” for Persistent AF Ablation
1. Risk Factor Modification
2. New energy sources (Cryo-balloon)
3. Substrate Ablation (Fibrosis – CMR vs Egm)
4. Rotor Mapping (Endocardial vs Epicardial)
Pathak et al 2014
Weight loss, CPAP, HTN and DM Rx!
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Inclusion – symptomatic drug refractory PerAF for 1st AF ablationExclusion – AF > 1 yr, LA > 6 cm, significant valve dz, CHF, prior ablationResults – 157 pt ablated with CB technology and F/U for 1 yr
PVI successful in 100%LA procedure time = 112 + 30 min3 complications (2 phrenic nerve, 1 effusion)NSR @ 1yr in 82% (17% on AARx), 68% NSR off AARx
Conclusion – In Short term PerAFPVI with CB is a reasonable approach
Straube et al, Journal of Cardiology 2016
LA Electro-anatomic Voltage mapping Normal Voltage > 1.5 mVLow Voltage Areas (LVA) < 0.5 mV RFA strategy – PVI alone if no LVA
PVI + BIFA of LVAsLVAs – Anterosept 40%, Posterior – 30%
31 PerAF pts
70%
80%
Kottkamp et al JCE 2016
Substrate Mapping (voltage vs CMR)
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Is Topera / FIRM the Wrong Technology or Wrong ConceptBaskets fit poorly in both RA and LA, often > 50% of basket EGMs aren’t useable
Endocardial recordings may be inadequate for rotor localization
Buch et al, Heart Rhythm 2016
Topera / FIRM - Endocardial Rotor Mapping
Body Surface Rotor MappingNon-invasive epicardial driver area localization
Arrhythmia and Electrophysiology Review 2015
CT Guided Surface Mapping
70% LA / 30% RA80% reentry20% focal
AF Duration
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Ablation OutcomesDriver ablation alone terminated 75% of PerAF
Haissaguerre et al, Circulation 2014
• Short term PerAF / progressed from PAF = Standard WACA PVI (RFA or Cryo-Balloon)
• Intermediate term PerAF (< 1 yr) without significant fibrosis / right atrial pathology = WACA PVI and RFA of easily identifiable triggers
• Long standing persistent AF or PerAF from onset with significant fibrosis / right atrial pathology = More extensive ablation with WACA PVI + additional lesions vs Consider surgical LA / RA approach
A Practical Approach for Ablation of Persistent AF