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 True PAF: PVAI Sustained PAF: + LA roof line + RA flutter line Persistent AF: + LA floor line LS Persistent AF: + Epicardial CS ablation + LA septal ablation + CFEs at LAA os

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) % Male46.8%76.9% Age (yrs)57.3 ± 10.5 [32-78]59.2 ± 8.3 [41-77] BMI28.4 ± ± 3.5 AF duration (yrs)5.5 ± ± 6.7* Number of prior AADs2.6 ± ± 1.2 Ejection Fraction63 ± 11%62 ± 6% LA diameter (echo)4.6± 0.5 cm4.2 ± 0.4 cm LA diameter (CT)4.2 ± 0.6 cm4.5 ± 0.8 cm LA volume (CT)126 ± 24 ml149 ± 32 ml * * = p < 0.05 Results: Baseline data

Persistent AF (n=27)Longstanding PsAF (n=31) % Male85.0%93.5% ** Age (yrs)53.6 ± 12.6 [16-68]57.4 ± 8.3 [40-72] BMI30.2 ± ± 5.3 AF duration(yrs)4.9 ± ± 2.1 Time in persistent AF (months) 9.4 ± ± 17.9 Number of prior AADs1.9 ± ± 0.8 Prior CV79% [1-5]97% [1-4]* CV successful (%)63%53% Ejection Fraction54.3 ± 11.5%49.8 ± 17.0% LA diameter (echo)4.5 ± 0.8 cm4.7 ± 0.6 cm LA diameter (CT)4.76 ± 0.85 cm5.15 ± 0.93 cm LA volume (CT)148.1 ± 47.1 mls161.7 ± 41.9 mls * P < 0.05 * * P = 0.001

Results: Ablation procedure PAFSustained PAF PsAF Longstanding PsAF PVs isolated3.65 (2-4)3.64 (2-4)3.65 (3-4)3.84 (3-4) Procedure duration (min) 173 ± ± ± 39**229 ± 47* Fluoro time (min) 29.1 ± ± ± ± 15.1** Fluoro dose (cGy) 4029 ± ± ± ± 2753 ** Cardioversion n (%) 3(7)7 (27)15 (56)23 (74) Complications 1 tamponade 1 pseudo- aneurysm 0 1 embolic TIA * P = ** P <

Mean Follow up duration PAF12.0 ± 1.0 months Sustained PAF11.0 ± 1.7 months Persistent AF10.6 ± 1.1 months Longstanding Persistent AF12.6 ± 1.4 months All patients followed up for approximately 12 months

3 months6 months12 months PAF (n=47)N=47 Cured/ Significant Improvement Some Improvement Same/ worse Sustained PAF (n=26)N=26 Cured/ Significant Improvement Some Improvement Same/ worse 03.8 Persistent AF (n=27)N=27 Cured/ Significant Improvement Some Improvement Same/ worse LS Persistent AF (n=31)N=31 Cured/ Significant Improvement 67.7 Some Improvement 9.7 Same/ worse

Symptomatic cure – patient satisfaction

12 month follow up results 81% 68% 88% 79% Cured/significant improvement Some improvement No better/worse 79% 92% 74%

Freedom from documented AF/ AT

Follow up Redo 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%)/108.6 ± 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