AF ablation: A single operator’s experience over 3 years (2007 – 2009) Barker D, Patwala A, Damm E, Hall M, Snowdon R, Gupta D Liverpool Heart and Chest.

AF ablation:A single operator’s experience

over 3 years (2007 – 2009)

Barker D, Patwala A, Damm E, Hall M, Snowdon R, Gupta D

Liverpool Heart and Chest Hospital, UK

Background

• Inconsistent results of AF ablation

• ? Due to Heterogeneity amongst AF population

• Role of Trigger removal vs Substrate modification

Hypotheses

• Substrate modification can be achieved with linear lesions

• Incremental lesion set depending upon disease stage

• Individualised approach may standardise single procedure success rates across AF population

• ? Safety and feasibility of this approach

Methods: Definition of AF groups

• 131 consecutive patients coming for AF ablation (DG)

• Sustained PAF: Patients with PAF, with ≥ 2 of

• Any individual AF episodes > 24 hours

• History of AF > 5 years

• LA size on Echo > 4.5 cm

• Age > 65 years

• Documented flutter

• True PAF

• Persistent AF (> 7 days/ Needed Cardioversion)

• Longstanding Persistent AF (>12 months)

Methods Ablation approach

• PVAI with Wide area circumferential ablation

• PVAI guided and confirmed by PV catheter

• Continuous RF:

• LA: 35 W, 50°C, 10 ml/ min flow

• CS: 25 W, 50°C, 30 ml/ min flow

• CTI: 50W, 50°C, 30 ml/ min flow

• 3D mapping:

• 80% with CT image integration

Methods: Prescribed lesion set

PAF Sustained PAF

Persistent AF Longstanding PsAF

Methods • Linear lesion integrity tested by

• Loss of recordable signals along line

• Double potentials across line if in SR/ flutter

• Conduction detour not confirmed routinely

• Mitral Isthmul Line not usually attempted

• unless peri-procedural peri-mitral flutter(s)

• Procedure limit of 4/5 hours

Patients not offered Catheter ablation if

• Very long standing Persistent AF (>3 years)

• Very large LA (>5.5 cm)

• Morbid Obesity (BMI >40)

Methods Exclusion criteria

Follow-up strategy

• AAD therapy continued for 2/3 months

• Clinic and ECG review at least every 3 months

• HRN Contact Line for inter-current support

• Ambulatory monitoring to assess symptoms

• Early post-op arrhythmias

• DC CV if sustained and poorly tolerated

• Redo ablation deferred for at least 5-6 months

PAF (n=47) Sustained PAF (n=26)

% Male 46.8% 76.9%

Age (yrs) 57.3 ± 10.5 [32-78]

59.2 ± 8.3 [41-77]

BMI 28.4 ± 3.9 27.6 ± 3.5

AF duration (yrs) 5.5 ± 5.2 7.2 ± 6.7*

Number of prior AADs

2.6 ± 1.4 2.2 ± 1.2

Ejection Fraction 63 ± 11% 62 ± 6%

LA diameter (echo)

4.6± 0.5 cm 4.2 ± 0.4 cm

LA diameter (CT) 4.2 ± 0.6 cm 4.5 ± 0.8 cm

LA volume (CT) 126 ± 24 ml 149 ± 32 ml *

* = p < 0.05

Results: Baseline data

Persistent AF (n=27) Longstanding PsAF (n=31)

% Male 85.0% 93.5% **

Age (yrs) 53.6 ± 12.6 [16-68] 57.4 ± 8.3 [40-72]

BMI 30.2 ± 4.7 30.6 ± 5.3

AF duration(yrs) 4.9 ± 3.3 3.5 ± 2.1

Time in persistent AF (months)

9.4 ± 7.1 19.0 ± 17.9

Number of prior AADs

1.9 ± 0.6 2.5 ± 0.8

Prior CV 79% [1-5] 97% [1-4]*

CV successful (%) 63% 53%

Ejection Fraction 54.3 ± 11.5% 49.8 ± 17.0%

LA diameter (echo)

4.5 ± 0.8 cm 4.7 ± 0.6 cm

LA diameter (CT) 4.76 ± 0.85 cm 5.15 ± 0.93 cm

LA volume (CT) 148.1 ± 47.1 mls 161.7 ± 41.9 mls * P < 0.05 * * P = 0.001

Results: Ablation procedure

PAF Sustained PAF

PsAF Longstanding PsAF

PVs isolated

3.65 (2-4) 3.64 (2-4) 3.65 (3-4) 3.84 (3-4)

Procedure duration (min)

173 ± 46 192 ± 46 216 ± 39** 229 ± 47*

Fluoro time (min)

29.1 ± 9.9 37.7 ± 11.4 33.6 ± 12.6 38.0 ± 15.1**

Fluoro dose(cGy)

4029 ± 3601

2984 ± 3249

4908 ± 2357

5026 ± 2753 **

Cardioversion n (%)

3(7) 7 (27) 15 (56) 23 (74)

Complications

1 tamponade1 pseudo-aneurysm

0 1 pseudo-aneurysm

1 embolic TIA

* P = 0.001 ** P < 0.0005

Mean Follow up duration

PAF 12.0 ± 1.0 months

Sustained PAF 11.0 ± 1.7 months

Persistent AF 10.6 ± 1.1 months

Longstanding Persistent AF

12.6 ± 1.4 months

All patients followed up for approximately 12 months

3 months 6 months 12 months

PAF (n=47) N=47

Cured/ Significant Improvement

76.6 83.0 78.7

Some Improvement 12.8 8.5 14.9Same/ worse 10.6 8.5 2.1

Sustained PAF (n=26) N=26

Cured/ Significant Improvement

96.2 88.5 92.3

Some Improvement 3.8 7.7 3.8Same/ worse 0 3.8 3.8

Persistent AF (n=27) N=27

Cured/ Significant Improvement

81.5 77.8 74.1

Some Improvement 11.1 7.4 11.1Same/ worse 7.4 11.1 14.8

LS Persistent AF (n=31) N=31

Cured/ Significant Improvement

67.7 67.7 67.7

Some Improvement 9.7 9.7 9.7Same/ worse 22.6 22.6 22.5

Symptomatic cure – patient satisfaction

0

20

40

60

80

100

PAF (n=46)

Sustained PAF (n=26)

Persistent AF (n=27)

Longstanding PsAF (n=31)

Percentage symptom free

3 months 6 months 12 months

Longstanding PsAF (n=31)

12 month follow up results

81%

68%

88%

79%

Cured/significant improvementSome improvementNo better/worse

Sustained PAF (n=26)

PAF (n=47)

Persistent AF (n=27)

79%

92%

74%

Freedom from documented AF/ AT

0

20

40

60

80

100

PAF Sustained PAF Persistent AF Longstanding PsAF

Percentage free from AF

3 months 6 months 12 months

Follow upRedo

Ablation Pts/ablation

Time to Redo ablation

MAT on follow-up

PAF 9 (20%)/9* 10.5 ± 6.1 months (range 5 – 13)

1 atrial tachy

Sustained PAF

5 (21%)/6 (re-redo for flutter)

17.8 ± 5.2 months (range 9 – 22)

3 (2 typical, 1 atypical)

Persistent AF

3 (16%) /4 (re-redo for flutter)

7.7 ± 2.5 months (range 5 – 11)

2 (1 typical, 1 atypical)

Longstanding PsAF

8 (40%)/10 8.6 ± 3.8 months (range 4 – 14)

3 (3 atypical)

* 8 of the 9 redo cases had incomplete initial PVI

Conclusions

• Individualised ablation strategy based on incremental linear lesion placement feasible on practical grounds

• Not associated with greater risk of procedural complications

• Anatomical (3D mapping based) approach to linear lesion creation associated with acceptably low risk of MAT

• This strategy may result in some uniformity of results across the spectrum of AF patients