Stefano Nardi, MD, PhD

Tools to successfully Tools to successfully achieve PV isolation: achieve PV isolation:

efficacy and safety data efficacy and safety data

“ “SANTA MARIA” GENERAL HOSPITAL - TERNISANTA MARIA” GENERAL HOSPITAL - TERNI THORACIC SURGERY AND THORACIC SURGERY AND

CARDIOVASCULAR DEPARTMENT ARRHYTHMIA ELECTROPHYSIOLOGIC CARDIOVASCULAR DEPARTMENT ARRHYTHMIA ELECTROPHYSIOLOGIC CENTER AND CARDIAC PACING UNIT CENTER AND CARDIAC PACING UNIT

Who benefits from AF ablation ?

Atrial FibrillationAtrial FibrillationMechanisms and ConsiderationsMechanisms and Considerations

Atrial Fibrillation MechanismsAtrial Fibrillation Mechanisms

• PVs as TRIGGER and PERPETUATORS

• SUBSTRATE with CRITICAL MASS

• GANGLIONIC PLEXI affecting vagal innervation

• ROTOR sites critical to the maintenance of reentry

How does it work?

RF

Pulmonary vein anatomy

TRIGGERTRIGGER

Haissaguerre, NEJM ’98

It’s really important to use the appropriate technique for

AF ablation

Different TechnologiesDifferent TechnologiesMappingMapping• Point by pointPoint by point

• LassoLasso• SpiralSpiral• BasketBasket

TrackingTracking• XrayXray

• CARTOCARTO• LocaLisaLocaLisa• NavXNavX• RPMRPM

• ICEICE

AblationAblation• ConventionalConventional

• 8 mm tip8 mm tip• Irrigated tipIrrigated tip• InvestigationalInvestigational(balloon, cryo...)(balloon, cryo...)- Framework for ablationFramework for ablation

- Mapping guidanceMapping guidance

- Anatomic localizationAnatomic localization

- Tagging of ablation sites- Tagging of ablation sites- Determine Determine catheter contactcatheter contact

- Improved Improved efficiency of efficiency of energy deliveryenergy delivery

How we can approach AF ablation ?

Different Approaches

What is really useful?3D mapping system in AFib 3D mapping system in AFib

Cutaneous patches and conventional catheter for tracking (NavX)

Superimposed EM field With a dedicated mapping

catheter (CARTO)

Point-by-Point

Medium-Low

Virtual Geometry reconstructionVirtual Geometry reconstruction

Virtual Geometry reconstructionVirtual Geometry reconstruction

Anatomical Approach Anatomical Approach CLAACLAA

• 251 Patients• 54±12 min of RF

End Point: (75%)• PVP < 0.1 mV• Delay > 30 ms

Success off AADs:• 148/179 PaAF (83%)• 40/72 PeAF (55%)

Pappone, Circulation ‘01Pappone, Circulation ‘01

AuthorsAuthors Success w/o AADsSuccess w/o AADs

PAPPONEPAPPONE 83% FAP/75%FAC83% FAP/75%FACJACC 2003JACC 2003

STABILESTABILE 38% FAP/FAC38% FAP/FACCirculation 2003Circulation 2003

HOCINIHOCINI 60% FAP*60% FAP*AbstractAbstract

ORALORAL 88% FAP (+ line)*88% FAP (+ line)*Circulation 2003Circulation 2003

Anatomical Approach Anatomical Approach CLAACLAA

Pulmonary Vein isolationAtrial Fibrillation ablationAtrial Fibrillation ablation

Authors Success Rate (%)Success Rate (%)

HaissaguerreHaissaguerre Circulation 2000Circulation 2000 73%73% PAFPAFChen SAChen SA Circulation 2001Circulation 2001 81%81% PAFPAFErnstErnst PACE 2003PACE 2003 69%69% PAFPAFArentzArentz Circulation 2003Circulation 2003 62%62% PAFPAFCappatoCappato Circulation 2003Circulation 2003 8888%% PAFPAFMarroucheMarrouche JACC 2002JACC 2002 90%90% PAF PAF OralOral Circulation 2002Circulation 2002 85% 85% PAF PAF

22%22% CAFCAF

Pulmonary Vein isolationAtrial Fibrillation ablationAtrial Fibrillation ablation

Pulmonary vein anatomy the first challenge

Left common trunk 3 right lower veins

Normal

Left Atrial/PVs junctionLeft Atrial/PVs junction• Functionally is a “BROAD BAND”

• Wide, complex & articulate anatomy, (irregular disposition of myocardial sleeves (Ho, JCVE. ‘99; Heart ‘01; Saito, JCVE. ’00)

• Arrhythmogenic nature due to (Embrional Nature) or micro-reentry (anisotropic carachteristic of junction) (Hocini M, Card. Res ’02, Arora, Circulation 03)

Ernst, JACC ‘03Ernst, JACC ‘03

Complete LesionsComplete LesionsA – 5% A – 5% B – 21% B – 21% C – 50% D - C – 50% D - 58-65%58-65%

Anatomical Approach (CLAA)Anatomical Approach (CLAA)

LIPV

CS pacing

Mitral

Anatomical CLAA: Incomplete PVI in ~ 60%Anatomical CLAA: Incomplete PVI in ~ 60%

70 ms70 ms

IIIIIIIIIIIIV1V1

PV1-2PV1-2

PV10-1PV10-1

CSDCSD

CSPCSP

Limitations of CLAA

• What substrate is “real target” for AF ablation ?• Almost 60% of pts no PVI • Extensive LA damage• LA flutters more common (20%)

V1V1

RF probeRF probe(ostial)(ostial)

LIPV 1-2LIPV 1-2

2-32-3

3-43-4

4-54-5

5-65-6

6-76-7

7-87-8

8-98-99-109-1010-110-1LA appLA app

Discrete Residual PV bundle - Producing ArrhythmiaDiscrete Residual PV bundle - Producing Arrhythmia

• Inadequate Mapping of complex anatomical substrates

Limitation of standard SOCALimitation of standard SOCA

• PVs potential running along the LA posterior wall could be missed with a standard EP approach

• A complex design for transition between anatomical structures

• SUCCESS RATE related to the ability to apply RF at predefined target sites, and the identification of all PVs bundles could be challenging

Limitation of standard SOCALimitation of standard SOCAIIIIII

PV 1-2

PV 10-1

V1

CSP

• FLUOROSCOPY has a poor soft-tissue resolution, with high exposure to ionizing radiation.

• Conduction recovery after a previously successful PVI could be due to a ”SUB-OPTIMAL” identification of all PVs pot.

• A multi-step approach provides a significant clinical

benefit and suggest that PVs are an important “End Point”

Which is the impact of the new technologies ?

Atrial Fibrillation ablationAtrial Fibrillation ablationvirtual geometry reconstructionvirtual geometry reconstruction

Atrial Fibrillation ablationAtrial Fibrillation ablation3D Mapping System3D Mapping System

Atrial Fibrillation ablationAtrial Fibrillation ablationPVs analysisPVs analysis

• Single ablation electrode (point-to-point)

• Requires high energy • ~ 75% of of power is lost to blood pool• Unipolar RF energy only• Lack of CTR over lesion creation

Standard Catheter Technologytechnology Review

Flow• Risk of steam pops from a boiling

process with gas expansion as tissue temp increases

• Needs saline cooling / flush

PV Isolation using the Cryo-Balloon

HD Mesh Ablator

HD Mesh Ablator

Multi-electrode Catheter Ablation- Steerable Catheters able to map, pace and

ablate from all electrodes- Tailored lesions (i.e., depths, lengths,

configurations) according to unipolar and or bipolar setting configuration

Multi-electrode Catheter Ablation RF energy modes

Current Flows from Abl Electrode to Return Electrode

• 100% Power is Unipolar

Current Flows between Abl Electrode on Cath only • 100% Power is Bipolar

50% of Power is Bipolar50% of Power is Unipolar

66.7% of Power is Bipolar33.3% of Power is Unipolar

80% of Power is Bipolar20% of Power is Unipolar

Different RF Delivery Mode

Creates contiguous lesions

Cross Section

Multi-electrode Catheter Ablation

Atrial Fibrillation ablationAtrial Fibrillation ablationVagal GangliaVagal Ganglia

• The purpose of AF Survey I was to assess on a large scale level methods, safety and efficacy of curative CA of AF (1995-2002)

• The rationale for AF Survey II is to evaluate the impact of newer techniques applied to broadened indications, according to the increased investigator’s experience

• Parameters were compared and selected for a post-hoc analysis and results reflect exclusively the experience of singles centres

AF Survey II

AF Survey II

Previous Survey

Current Survey

Period investigated 1995-2002 2003-2006

Nr of centers 90 85

No. of pts 8,745 16,309

No. of pts per center 97 192

No. procedures 12,830 20,825

No. procedures per pts 1.5 1.3

Male, % 63.8 60.8

Lower and upper age limit for entry

18-82 15-90

% of centers performing ablation of- Paroxysmal AF 100 100

- Persistent AF 53.4 85.9

- Permanent AF 20 47.1

Cappato R, Boston 2008

efficacy and safety data

Type of AF No. of Centers

No. of Pts

Success without AADs Success with AADs Overall SuccessNo Pts

Total Rate Median

74.9[64.9-82.6]

64.8[52.4-72.0]

63.1[53.3-71.4]

No Pts

Rate Median

9.1[0.2-14.7]

10.0[0.8-15.2]

7.9[0.9-15.9]

NoPts

Rate Median

Paroxysmal 85 9,590 6,580 1,290 7,870 84.0[79.7-88.6]

Persistent 73 4,712 2,800 595 3,395 74.8[66.1-80.04

Permanent 40 1,853 1,108 162 1,270 71.0[67.4-72.3]

AF Survey II

Cappato R, Boston 2008

Relationship between success rate and type of Ablation Catheter

Relationship between success rate and type of Ablation Catheter

Type of Catheter

No Center

No Pts Success without AADs Success with AADs Overall Success

Total No of Pts

Total Rate Median

68.3[48.4-80.8]

67.9[44.7-73.6]

68.1[46.2-73.6]

Total No of Pts

Rate Median

11.5[8.6-26.7]

9.0[0.0-14.8]

10.0[0.0-20.0]

Total No of Pts

Rate Median

4-mm 23 2,892 1,803 609 2,412 79.8[55.0-87.2]

Irrigated/ Cooled

39 6,674 3,891 721 4,612 76.9[56.4-88.5]

TOTAL 62 9,5665,694 1,330 7,024 78.1

[66.8-86.7]

AF Survey II

Cappato R, Boston 2008

Type of Strategy

No Center No Pts

Success without AADs

Success with AADs

Overall Success

Total No of Pts

Total Rate Median

78.0[67.9-78.8]

69.8 [56.8-73.4]

71.1[58.3-78.0]

Total No of Pts

Rate Median

6.7[0.0-13.3]

10.4[5.1-13.0]

10.0[0.0-13.0]

Total No of Pts

Rate Median

Lasso 21 3,722 2,616 499 3,115 84.7[78.8-89.5]

Carto 33 7,059 4,369 795 5,164 80.2[66.8-83.8]

TOTAL 54 10,781 6,985 1,294 8,279 81.0[73.3-84.0]

AF Survey II

Cappato R, Boston 2008

Relationship between success rate and type of Ablation Catheter

Major ComplicationsType of Complication No of Pts Rate,%

Death 25 0.15Tamponade 213 1.31

Pneumothorax 15 0.09

Haemothorax 4 0.02

Sepsis, abscesses or endocarditis 2 0.01Permanent diaphragmatic paralysis 28 0.17

Total femoral pseudoaneurysm 152 0.93

Total artero-venous fistulae 88 0.54

Valve damage/requiring surgery 11/7 0.07

Atrium-esophageal fistulae 3 0.02

Stroke 37 0.23

Transient ischaemic attack 115 0.71

Pulmonary veins stenoses requiring intervention 48 0.29

Total 741 4.54

AF Survey II

Cappato R, Boston 2008

• Results reflect the experience of centers electing to respond

• Intermediate-term follow up data• Post-ablation asymptomatic AF not investigated• CA of AF evolving over the time and these data

may not reflect the efficacy and safety rates of 2009

considerationsAF Survey II

• PVI is efficacy in 52-84% of PAF non-PVI is efficacy in 52-84% of PAF non-inducible and results in clinical successinducible and results in clinical success

• Substrate modification is likely to be Substrate modification is likely to be required in 30% of PAF and most CAF, but required in 30% of PAF and most CAF, but needs needs technological improvements technological improvements • An individually tailored approach is neededAn individually tailored approach is needed

What is the future for What is the future for satisfactory treatment of AF ?satisfactory treatment of AF ?

What is success?

• Complete freedom of AF, off drug RX?• No symptoms, but drug Rx required?• Dramatic decrease in symptoms, but

drugs still required?• QoL• How do we detect asymptomatic

episodes?• Anticoagulation ………………...?

What is the future for What is the future for satisfactory treatment of AF ?satisfactory treatment of AF ?

• Maintaining sinus rhythm (cure of AF) must Maintaining sinus rhythm (cure of AF) must remain our goalremain our goal• Indications for AF ablation will expand ? Indications for AF ablation will expand ? Role in complicated AFRole in complicated AF• Non-inducibility may be a useful procedural Non-inducibility may be a useful procedural endpoint to rationalize strategiesendpoint to rationalize strategies

Catheter Comparison4mm Tip Catheter PVAC

Electrode Shape

Electrode Surface Area

33.7 mm2 13.64 mm2

Power Input 35 W Max 10WCurrent Density 0.016 A/mm2 0.015 A/mm2

Atrial Fibrillation ablationAtrial Fibrillation ablationvirtual geometry reconstructionvirtual geometry reconstruction

Be carefull don’t miss the right way

Technique no. of centers no. of patients %

RAC 8 75 0.1CA-TF 10 222 1.7OED 34 3,889 27.4Cartow/o PV isolation 15 1,460 10.3w/ PV isolation 37 5,394 37.9

3D non-contact 11 663 4.7Basket 10 150 1.1CFAEs 16 349 2.4Other 5 968 6.9Combination 19 1,048 7.4

Total 165 14,218 100.0

Cappato R, Boston 2008

AF Survey IIefficacy and safety data

Previous Survey

Current Survey

Proportion (%) of centers using as exclusion- Left atrial size upper limit 46.3 68.2- Lower cut-off limit of LVEF 64.3 22.4Success rate (%, median)- Free of AADs 52.0 64.3- With AADs 23.5 12.5- Overall 75.5 76.9Overall complication rate (%) 5.9 4.5Iatrogenic flutter 3.9 8.3

Entry Criteria, Outcome and Complications

Abstract Ref Pts Efficacy SafetyACUTE RESULTS OF PVI IN PTS WITH PaAF USING A SINGLE MESH CATHETERSteinwender C, Hönig S, Leisch F, Hofmann R.

JCVE ‘09

26 PaAF Acute: PVI in 99/102 (97%) PVs

Follow-Up: 6-month FU in 13 pts:8/13 (61%) of success2/13 (15%) improved3/13 (23%) failure

Pericardial effusion (pericardocentesis) in 1 ptNo other complication during the procedure or the subsequent hospital stay were observed. RF ABLATION OF

PaAF BY MESH CATHETERPratola C, Notarstefano P, Artale P.

JICE ‘09

15 PaAF Acute: PVI in 40 pts (100%)

Follow-Up: NA

No complications occurred during and after or procedures.

Clinical experience with a single Cath. for Map/Abl of PV ostium De Filippo P

JCVE ‘08

17 pts PaAF (10pts) PeAF (7 pts)

Acute: 100% (17/17) for LUPV, LIPV and RUPV 47% (8/17) for RIPV.Follow-up: 11±4 mo, 64% of pts in SR (8/10 PaAF and 3/7 for PeAF)

No complications occurred

either acutely or at follow-

Up

HD Mesh Ablator

ResultsResults

PV Isolation using the Cryo-Balloon

• Successfull electrical isolation of 97% PVs in a single procedure (28 mm Balloon)

• Follow Up of 89 ± 66 days – 15 pts. free of AF (75%)– 5 pts. reduced AF burden but still AF

• No complications, besides of 1 PN palsy

Asklepios Klink St. Georg, Hamburg

Multi-electrode Catheter Ablation

- Anatomically designed lesions - Large footprint for map/abl with a

single Cath placement- Energy delivered in a new/novel

way for CTR lesions size

• Low Power RF Energy Delivery • Different and Selectable RF

energy modes

• Ablation and Return Electrodes Same Potential and Phase Angle

• Current Flows from Ablation Electrode to Return Electrode

• 100% Power is Unipolar

Unipolar Only RF energy modes

Ablation Electrode

Tissue

Return Electrode

Bipolar Only RF Delivery Mode

• Ablation and Return Electrodes Different Pot. and Phase Angle

• Return Electrode Off• Current Flows Between

Ablation Electrode on Cath only• 100% Power is Bipolar

Ablation Electrode

Tissue

Return Electrode

• Electrode design driven by the catheter shaft diameter

• Single ablation electrode (point-to-point)• Requires 35 – 40 Watts • ~ 75% of surface area in blood pool

(i.e., 75% of power lost to blood pool)• Unipolar RF energy only• 2-D Cath requiring generally 3-D Imaging• Lack of CTR over lesion creation and Cath

placement

Standard Catheter Technologytechnology Review

Flow

Standard Catheter Technology Clinically Review

• Risk of steam pops from a boiling process with gas expansion as tissue temp increases

• Needs saline cooling / flush• “Point by point” RFCA strategies• Requires precise catheter positioning

(high level of skill) Flow

Atrial Fibrillation ablationAtrial Fibrillation ablationAnatomical considerationsAnatomical considerations