Audit of ablation procedures for AF Barts and The London

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 (1998): Stewart, S. et al. "Cost of an emerging epidemic: an economic analysis of atrial fibrillation in the UK." Heart 90.3 (2004):

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

Non pharmacological methods Pacemaker – Pace to suppress triggers of AF – Multisite or biatrial pacing Atrial defibrillators Surgical ablation Catheter ablation

Mechanisms of AF

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

Pulmonary vein isolation

Linear ablation in the left atrium

Catheter maze

Standards from published data ProcedureCentre/DateN Permanent AF % Complication rate % Repeat Procedures % Maintenance of SR % LA linear ablation Kuck Hamburg (if lines complete) WACA Pappone Milan PAF 68 Permanent 4 PVI Haisaguerre Bordeaux (66 off drugs)

Worldwide survey of AF ablation Cappato 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 – Right atrial maze – Target PVI – Electrical disconnection of all PVs Outcomes – 8745 pts in 90 centres – 27.3% >1 procedure – 76% asymptomatic (24% on antiarrhythmic drugs) – 6% major complication rate

St Bartholomew’s data PATS database (EP and EP2) Research database – Catheter maze study – Coarse AF study Patient letters – DMS/EPR viewer Telephone patients

Total number of procedures 100 procedures in 73 patients

Increasing number of procedures

Patients N=73 50±8 years 58M 15F Cardiac diagnosis: Type of AF:

Outcomes: improvement in symptoms?

Outcomes: maintenance of sinus rhythm?

Need for antiarrhythmic drugs?

Need for repeat procedures? Number of procedures per patient:

Success of 1 st procedure

Procedure times 281±120 49±25

Complications Major n=4 (4.5%) – 2 Tamponade – 1 Stroke – 1 Severe PV stenosis Up to June 03 (11.4%) Since July 03 (0%) Minor n=7 (8.0%) – 2 transient ST elevation – 2 mild PV stenosis – 1 tip of active fix pacing wire in RA – 2 haematoma

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 10±7 months

Catheter maze outcome * Index Catheter Maze N=23 AF or AFL recurrence Medium term Sinus rhythm N=17 (77%) Permanent AF accepted N=3 Repeat ablation * In AF awaiting further treatment N=2 1 death from unrelated cause 2 nd or 3 rd AF or AFL recurrence 2 4 1

Results: symptoms and QOL Baseline SR -6 ± 7+14 ± months change vs 6 weeks -34 ± 24*-6 ± 37 6 weeks change vs baseline - 58 ± 29 Modified Karolinska (0-140) *P < 0.05 AF or AFL

Surgical Maze – BRACUS stidy Bipolar Radiofrequency Ablation for Chronic atrial fibrillation in patients Undergoing mitral valve Surgery PatientDiagnosisOperationDateRhythm at follow up 65 ♀ MR due to RhVD MVR + TV annulplastyJune 04Atrial flutter 71 ♀ MR due to MVP MV and TV repair and annulplasty June 04SR 68♂ MR due to MVP MVRAug 04(AF)

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

St Bartholomew’s 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