AF ablation with 3D mapping: our technique and results Dr Dhiraj Gupta MRCP MD DM Liverpool Heart...

AF ablation with 3D mapping:

our technique and results

Dr Dhiraj Gupta MRCP MD DMLiverpool Heart and Chest Hospital

Northern UK AF experts Best Practice meeting Langdale Hotel, Cumbria 5 Feb 2010

Schema

Our approach to AF ablation at LHCH

Our reasons for each step

Our in-lab and follow-up results

Our approach in a nutshell

• PVAI with Wide area circumferential ablation

• CT image integration using CARTO

• Individualised lesion set prescription

• Aim to ablate out of AF, ideally to SR

• Procedure duration limit of 5 hours

CT image registration

• Critical part of the process

• 2 steps

• Single point Landmark registration

• Surface Registration with Fast Anatomical Mapping

• Takes 5-10 minutes

CT image segmentation

Fast Anatomical Map creation

Image Surface registration

Why the individualised approach?

• Heterogeneity amongst AF population

• Trigger removal vs Substrate Modification

• Aim to achieve high single procedure success rates

• Incremental risk with multiple procedures

• That’s what the patient wants

• That’s what the health economists want!

Patient selection criteria

• Patients not offered Catheter ablation if

• Very long standing Persistent AF (>3 years)

• Very large LA (>5.5 cm)

• Morbid Obesity (BMI >40), Sleep Apnea

• Significant RA dilatation (>LA)

• Patients not offered first redo at least for 6 months

• Not offered Second redo if still in PsAF

Not all AF patients are the same

• True PAF

• Short lived episodes, short history, normal sized LA

• Sustained PAF: 2 or more of the following

• AF episodes>24 hours, History of AF > 5 years, LA size >4.5 cm, Age >65 years, Documented flutter, High AF burden (most days)

• Persistent AF

• Long standing Persistent AF (>12 months)

Minimum RF Lesion set • True PAF

• PVAI using WACA

• Sustained PAF

• + LA roof line + RA flutter line

• Persistent AF

• + LA floor line + Mitral isthmus line

• Long standing Persistent AF

• + Epicardial CS ablation+ CAFÉ ablation

Paroxysmal PAF

Sustained PAF

Persistent AF

Long standing Persistent AF

Surgical Maze for ‘Permanent AF’

* SM Prasad et al, J Thorac Cardiovasc Surg 2003; 126: 1822-27

•Still the Gold standard in terms of results

•96% free of AF at 5 years*

Results with ‘Catheter Maze’

N Redo AAD therapy Results Complications

HaissaguerreJCE 2005

60 1/2 Stopped at ablation

95% at 11 months

2 Tamponades

OralNEJM 2006

77 1/3 Amio 6/52 pre & 3/12 post

77% at 1 year

0

PostchCirc 2008

88 1/2 Stopped at ablation

81% at 20 months

2 Tamponades1 TIA

LoJCE 2009

87 1/4 AAD for 2/12 post

79% at 21 months

1 Tamponade

Why CT image integration?

• Forewarned is forearmed: PV anatomical variations

• Common Left Pulmonary Vein

• Additional pulmonary vein(s)

• Important anatomical information

• thickness of the LAA ridge, intervenous carina

• extent of the PV antra

• length of the mitral isthmus

Why CT image integration?

• Dramatically reduces procedural fluoro times:

• <10 minutes for PAF cases

• 10-20 minutes for PsAF cases

• Decreases fatigue

• Removes ‘the fear of the unknown’…..

• Demystifies AF ablation for the nurses/ radiographers!

Why CARTO rather than ESI?

• Unmatched catheter stability

• no catheter ‘dive’ with onset of RF delivery

• Allows linear lesions

• No need for stable intracardiac reference

• Ability to perform activation mapping if needed

• Great CT image integration software

Advances with CARTO-3

• Hybrid of impedance and magnetic catheter location

• Ability to see all catheters

• Ability to create fast anatomical maps

• Makes CT image integration easier

• More streamlined patient set-up

Why WACA?

• PV ostial/ antral triggers

• Substrate modification by Atrial debulking

• Less risk of PV stenosis

• Quicker than segmental PVI

• Easy to anchor linear lesions on either side

• ‘Et tu, Bordeaux?!’

Why our RF settings?

• Continuous RF: 35 W, 50°C, 10 ml/ min flow

• Quicker signal obliteration than 30/25 W

• Short procedure time (20-30’ per WACA)

• Prevents peri-lesion edema (? reconnection risk)

• RF controlled by Foot pedal

• Frees up a cardiac physiologist

• Imposes discipline on use of X-ray pedal!

Our results

131 consecutive pts. between Jan 08-July 09

Individualised ablation strategy

• True PAF (n=45)

• PVAI using WACA

• Sustained PAF (n=31)

• + LA roof line+ RA flutter line

• Ps AF (n=22)

• + LA floor line+ Mitral isthmus line

• Long standing Ps AF (n=33)

• + Epicardial CS ablation+ CAFÉ ablation

In-lab results

• All patients received prescribed minimum lesion set

• Mean Procedure time 173 min (98-300)

• Fluoroscopy times

• Mean 26.5 min (13-58) (as pre-CARTO 3 era)

• Now with CARTO-3 (n=36): Mean 14 min (6-21)

• Complications

• 1 tamponade (PVI group), 1 AV fistula

Our follow-up strategy

• Antiarrhythmic drug therapy for 2-3 months

• Early post-op arrhythmias

• DC CV if sustained and poorly tolerated (n=1)

• No redo ablation procedure for at least 6 months

• Mean follow up 11.3 months (6-24)

Our Clinical Results

• Definition of Procedural Success:

• No symptoms beyond 3 months, AND

• Absence of AF/AT on 24 hour Holter at 6 mo

• Single procedure success rates at 6 months

• PAF 84%

• PsAF 86%

• Sustained PAF 77% (p=0.05)

• Long standing PsAF 64% (p<0.001)

Conclusions

• Single procedure success should be the goal

• Most patients need substrate modification in addition to trigger removal

• This needs application of linear lesions

• 3D mapping guided ablation the gold standard

www.heartrhythmspecialist.co.uk

Thank You

Acknowledgements to Dr Richard Schilling, my mentor and guide