Surgical vs catheter ablation for AF Richard Schilling

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Surgical vs catheter ablation for AFRichard
Schilling
St Bartholomew's Hospital, Queen Marys
University of London
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Atrial fibrillation originates in the left atrium
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Mechanisms for AF Moes multiple wavelet
hypothesis
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Focal AF RFA to disconnect PV potential
Haïssaguerre et al N Engl J Med 1998
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Mechanisms for AF
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Fractionated potential ablation
Nademanee et al JACC 2004
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Mechanisms for AF

• Paroxysmal vein isolation probably enough
• Persistent AF ablation success rate higher with
  linear ablation

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Surgical Approaches to AF

• Cut and sew strategies

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Surgical AF ablation procedures

• Adequate for Paroxysmal
• Minimally invasive

Melby et al Ann Surg 2006
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Surgical RF procedures
Melby et al Ann Surg 2006
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Mitral isthmus line
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Catheter ablation strategies
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Catheter ablation strategies
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Ablation of persistent AF

• PV isolation
• Roof line
• Line along roof of CS
• Fractionated potential ablation
• Ablation within the CS
• DC cardioversion (30 return to SR)

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Technologies used to achieve Surgical AF ablation

• Cut and sew
• Technically challenging
• Longer
• ?increased complications
• Robust electrical isolation

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Technologies used to achieve Surgical AF ablation

• Radiofrequency
• Monopolar
• Slow
• Unpredictable lesions
• Extracardiac trauma o-a fistula
• Bipolar
• Fast
• Usually transmural most patients with
  recurrence have PVI
• Limited access (MV isthmus/CS)

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Monopolar ablation

• 3 swine
• Cooled tip monopolar rf
• Mapping across linear lesion
• Histology of lesions

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Mapping across monopolar lesions

• Of 10 lines produced only 3 demonstrated complete
  block

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Technologies used to achieve Surgical AF ablation

• Ultrasound
• Easier to use minimally invasive
• ?efficacy
• ?transmurality
• Microwave
• ?similar to RF

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Technologies to perform catheter ablation

• Radiofrequency
• Cooled tip monopolar
• Limited energy (limited comps)
• Defined EP end point
• Recurrence
• Ultrasound/Cryo balloons
• Relatively venous
• Extracardiac damage (phrenic nerve)
• ?results

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Results of secondary surgical ablation
N1528 CS N2279 AS
Khargi et al Eur J Cardio-thoracic Surgery 2005
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Results of surgical ablation
Khargi et al Eur J Cardio-thoracic Surgery 2005
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Results of lone/primary AF surgical ablation

• N29 Cox III maze
• Time 253 mins
• Hospital stay 17 days (median) (ITU 1 day)
• 1 post op death (5 days Colon tumour!)
• 62/38 paroxysmal/persistent
• 21 previous ablation
• 79 AF free off drugs
• 14 pacemaker
• 10 bleed

Hemels et al Ann Thorac Surgery 2006
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Results of lone/primary AF surgical ablation

• N50 microwave thoracoscopic
• 4 complication (diaphragmatic paralysis)
• Hospital stay 3.7 days
• PAF/Persistent 62/38
• Success 70 (single ECG follow up)
• 10 underwent successful CA or CS

Melby et al Ann Surg 2006
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Results of lone/primary AF surgical ablation

• Bipolar RF
• N27
• Stay 3.3
• Procedure time 178 mins
• PAF 66
• No significant comps
• Success off drugs 65

Wolff et al J thoracic and cardiovasc surgery 2005
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Results of catheter ablation - Wide encirclement
without isolation

• Pappone n589
• 80 success (32 on drugs)
• Post op complications (permanent and parox) 0.8
  (2 tamponade)
• 7 long term comps
• follow up by transtelephonic monitoring

Pappone et al JACC 2003
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Fractionated potential ablation

• Nadamanee 2004
• 70 success
• 10 amiodarone
• 4 major complications (stroke, heart block,
  tamponade)

Nademanee et al JACC 2004
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Catheter ablation in permanent AF
31/41(76) in SR at 8.4 mths
MV
Earley et al. Heart 2005
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Practicalities of curative AF ablation

• Pre op - CT few weeks pre-op
• TOE on day
• ACT gt300 during procedure
• Procedure time 2-3 hours PAF/ 3-4 hours
  Persistent
• Post-op echo
• Warfarin loading on night of procedure
• Continues for 3 months if low risk
• Enoxaparin day after until INRgt2

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How has technology affected AF catheter ablation?
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Case Control Study of 3-D mapping vs CT
integration

• 105 patients
• 6 month follow up
• 7 day holter at 3 months
• Similar operator profile and experience

Kistler et al JCE 2006
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AF ablation results
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AF ablation results
Procedure characteristics
CT integration (n 53)
3D mapping (n 52)
P value
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Freedom from AT/AF off medication at 6 month
follow up
3D mapping (n 52)
P value
CT integration (n 53)
Kistler et al JCE 2006
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Complications of AF ablation

• 2 pericardial effusion/tamponade
• 3 Femoral haematoma
• lt0.5 stroke/TIA
• lt0.5 PV stenosis

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Recurrence

• Usually occurs lt3months (late recurrence is rare)
• May settle over a 3 to 6 month period
• Results in 28 to 40 of patients requiring redo

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Ablation vs drugs
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What about long term follow up

• Surgical data lone AF
• Most studies follow up annually for 1 3 years
• Methods ECG or telephone mailed/questionairre
• Holter only done in those with symptoms

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Long term surgical follow up
Helby et al J cardiovasc surgery 2006
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Long term surgical results
Melby et al Ann Surg 2006
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Long term results after catheter ablation

• Pappone
• Daily trans-telephonic monitoring

Pappone et al JACC 2003
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Long term results after AF ablation

• Personal data
• 150 patients with symptomatic AF gt2 year follow
  up (40 perisistent)
• Late recurrence in 3 (2 paroxysmal/1 persistent)
  all ablated successfully (gt1 year follow up)

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Where should we put the lesions?

• We dont know
• Results are similar whatever technique used
• Definitely isolate the veins
• For persistent do a roof line and RA isthmus
• Does SVC to IVC line add anything? (crista
  terminalis)
• Dont do a MV to LPV line unless you can prove
  block

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AF termination

• Paroxysmal always at the veins
• Persistent 35 terminate during ablation
• Termination does not predict outcome (?PV
  reconnection)

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What about warfarin?

• There is no controlled studies demonstrating
  either surgical or catheter ablation reduce risk
  of stroke
• High risk patients should remain on warfarin
  regardless of outcome

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Whats best surgical or catheter for secondary AF?

• Almost all patients undergoing other surgery who
  have AF should have PVI /- quality lines
• Monopolar lines are as likely to cause arrhythmia
  as they are to stop it

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Whats best surgical or catheter for lone AF?

• Surgical
• Higher first time success
• Longer stay
• More expensive
• Higher complications?
• Poorer outpatient management

• Catheter ablation
• Technically more difficult to learn and perform
• Truly minimally invasive
• Radiation exposure
• Similar procedure length

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Surgical vs catheter ablation

• Surgeons are looking to increase their repertoire
• There is a shortage of AF ablation cardiologist
  in the world
• There is no shortage of patients
• Easier to perform AF surgery than AF catheter
  ablation
• Issues over post-operative care/follow up

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Conclusion

• AF ablation continues to improve
• For catheter ablation high volume means good
  results
• Cure rates are outstanding for PAF and acceptable
  for persistent AF
• The epidemic may have a solution
• For lone AF catheter ablation is still the
  treatment of choice for many patients
• www.londonafcentre.com