Audit of ablation procedures for AF

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Audit of ablation procedures for AF

• Barts and The London

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AF burden

• Framingham
• Lifetime risk of developing AF 25
• Mortality SMR 1.9 ? 1.5 ?
• NHS audit
• 1 of budget spent on AF
• ??Quality of life
• Symptoms of AF
• Side effects of medication

Benjamin, E. J. et al. "Impact of atrial
fibrillation on the risk of death the Framingham
Heart Study." Circulation 98.10 (1998)
946-52. Stewart, S. et al. "Cost of an emerging
epidemic an economic analysis of atrial
fibrillation in the UK." Heart 90.3 (2004)
286-92
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Are effective treatments available?

• Antiarrhythmic drugs
• Toxicity AFFIRM
• No benefit over rate control
• SR has a prognostic benefit
• Rate control and anticoagulation
• As good as AADs
• Prognosis
• QOL
• Ximelagatran

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Non pharmacological methods

• Pacemaker
• Pace to suppress triggers of AF
• Multisite or biatrial pacing
• Atrial defibrillators
• Surgical ablation
• Catheter ablation

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Mechanisms of AF
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Ablation strategies

• Isolation/destruction of triggers
• Target pulmonary vein isolation (PVI)
• Total PVI other triggers

• Modification of atrial substrate
• Linear lesions in left atrium, right atrium or
  both
• Wide circumferential lesions around pulmonary
  veins
• Catheter maze

Left atrial maze and PVI
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Pulmonary vein isolation
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Linear ablation in the left atrium
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Catheter maze
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Standards from published data
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Worldwide survey of AF ablationCappato et al.
ESC 2004

• Data from 777 centres
• Number of cases
• 18 in 1995, 5050 in 2002
• Median of 37.5 cases per centre (range 1-600)
• Commonest procedure
• 1995-97 Right atrial maze
• 1998-99 Target PVI
• 2000-02 Electrical disconnection of all PVs
• Outcomes
• 8745 pts in 90 centres
• 27.3 gt1 procedure
• 76 asymptomatic (24 on antiarrhythmic drugs)
• 6 major complication rate

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St Bartholomews data

• PATS database (EP and EP2)
• Research database
• Catheter maze study
• Coarse AF study
• Patient letters
• DMS/EPR viewer
• Telephone patients

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Total number of procedures
100 procedures in 73 patients
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Increasing number of procedures
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Patients
N73 508 years 58M 15F
Type of AF
Cardiac diagnosis
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Outcomes improvement in symptoms?
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Outcomes maintenance of sinus rhythm?
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Need for antiarrhythmic drugs?
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Need for repeat procedures?
Number of procedures per patient
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Success of 1st procedure
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Procedure times
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Complications

• Minor n7 (8.0)
• 2 transient ST elevation
• 2 mild PV stenosis
• 1 tip of active fix pacing wire in RA
• 2 haematoma

• Major n4 (4.5)
• 2 Tamponade
• 1 Stroke
• 1 Severe PV stenosis
• Up to June 03 (11.4)
• Since July 03 (0)

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Catheter maze study

• Baseline characteristics
• 23 patients (19M 4F)
• 49 9 years
• AF duration 4 3 years(11 9 months
  continuously)
• 2.7 1.7 DCCV
• 3.3 1 antiarrhythmic drugs
• LA diameter 4.9 0.9 cm
• Mean follow up 107 months

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Catheter maze outcome
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Results symptoms and QOL
Modified Karolinska (0-140) P lt 0.05
SR
AF or AFL
58 29
-
Baseline
6 weekschange vs baseline
-34 24
-6 37
-6 7
14 1.4
6 months change vs 6 weeks
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Surgical Maze BRACUS stidy

• Bipolar Radiofrequency Ablation for Chronic
  atrial fibrillation in patients Undergoing mitral
  valve Surgery

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Conclusions

• Clinical need for improved pharmacological or non
  pharmacological treatments for AF
• AF ablation at St Bartholomews is effective and
  at a level with published data
• Low but important complication rate

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St Bartholomews as a lead national centre for AF
ablation

• Increasing number of cases
• Prospective symptom, QOL and rhythm collection
• Publishing and presenting our data
• Research
• Catheter Maze
• Coarse AF
• BRACUS
• Training
• Centre of excellence for industry
• Ensite NavX 4.0 and 5.0
• Digital Image fusion