Audit of ablation procedures for AFAudit of ablation procedures for AF

Barts and The London

AF burdenAF 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

Are effective treatments available?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 methodsNon pharmacological methods

• Pacemaker

– Pace to suppress triggers of AF

– Multisite or biatrial pacing

• Atrial defibrillators

• Surgical ablation

• Catheter ablation

Mechanisms of AFMechanisms of AF

Ablation strategiesAblation 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 isolationPulmonary vein isolation

Linear ablation in the left atriumLinear ablation in the left atrium

Catheter mazeCatheter maze

Standards from published dataStandards from published data

Procedure Centre/Date NPermanent

AF %Complication

rate %

Repeat Procedures

%

Maintenance of SR %

LA linear ablation

KuckHamburg 1999

84 23 6 -74

(if lines complete)

WACAPappone

Milan 2001 251 27 0.8 -

85 PAF68 Permanent

4 PVIHaisaguerre

Bordeaux 2002136 10 0.7 49

81(66 off drugs)

Worldwide survey of AF ablationCappato et al. ESC 2004

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% >1 procedure

– 76% asymptomatic (24% on antiarrhythmic drugs)

– 6% major complication rate

St Bartholomew’s dataSt 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 proceduresTotal number of procedures

0

5

10

15

20

25

30

35

Catheter

maze

LA maze +

PVI

Total PVI RA isthmus WACA PV LA flutter Target PVI RA maze

100 procedures in 73 patients

Increasing number of proceduresIncreasing number of procedures

6

21

36

46

0

510

1520

2530

35

4045

50

2001 2002 2003 2004

PatientsPatients

N=73 50±8 years 58M 15F

Normal

74%

Other

7%DCM3%

Hypertensive16%

Cardiac diagnosis:

Paroxysmal49%

Persistent3%

Permanent48%

Type of AF:

Outcomes: improvement in symptoms?Outcomes: improvement in symptoms?

0%

20%

40%

60%

80%

100%

Overall Paroxysmal AF Permanent

Resolved Some improvement No improvement

Outcomes: maintenance of sinus rhythm?Outcomes: maintenance of sinus rhythm?

0%

20%

40%

60%

80%

100%

Overall Paroxysmal AF Permanent

Sinus rhythm AF

Need for antiarrhythmic drugs?Need for antiarrhythmic drugs?

0%

20%

40%

60%

80%

100%

Overall in SR PAF in SR PermanentAF in SR

Overallsymptomsimproved

PAFsymptomsimproved

PermanentAF

symptomsimproved

No drugs On drugs

Need for repeat procedures?Need for repeat procedures?

0%

20%

40%

60%

80%

100%

Symptoms improved Currently in SR

1 2 3

Number of procedures per patient:

Success of 1st procedureSuccess of 1st procedure

0%

20%

40%

60%

80%

100%

Cathetermaze n=23

4 veinisolation

n=9

WACAcarto n=9

LAmaze_PVI

n=4

RAisthmus

n=9

Symptoms improved In SR

Paroxysmal >1 Procedure needed

Procedure timesProcedure times

0

100

200

300

400

Procedure Time Screening time

Mins 281±120

49±25

ComplicationsComplications

• 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 studyCatheter 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 outcomeCatheter maze outcome

9 + 2*

8

3

4

9

14

Index Catheter MazeN=23

AF or AFL recurrence

Medium termSinus rhythmN=17 (77%)

PermanentAF accepted

N=3

Repeat ablation

* In AF awaitingfurther treatment

N=2

1 death fromunrelated cause

2nd or 3rd

AF or AFL recurrence

2

4

1

Results: symptoms and QOLResults: symptoms and QOL

Baseline

SR

-6 ± 7+14 ± 1.46 months

change vs 6 weeks

-34 ± 24*-6 ± 376 weeks

change vs baseline

-58 ± 29

Modified Karolinska

(0-140)

*P < 0.05

AF or AFL

Surgical Maze – BRACUS stidySurgical Maze – BRACUS stidy

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

Patient Diagnosis Operation Date Rhythm at follow up

65 ♀MR due to

RhVD MVR + TV annulplasty June 04 Atrial flutter

71 ♀MR due to

MVPMV and TV repair and

annulplastyJune 04 SR

68♂MR due to

MVPMVR Aug 04 (AF)

ConclusionsConclusions

• 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

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