Optimal Method and Outcomes of Catheter
Ablation of Persistent AF:
The STAR AF 2 Trial
Atul Verma, Jiang Chen-yang, Tim Betts, John Radcliffe, Jian Chen,
Isabel Deisenhofer, Roberto Mantovan, Laurent Macle,
Carlos Morillo, Prashanthan Sanders
on behalf of the STAR AF 2 Investigators
ClinicalTrials.gov NCT01203748
The STAR AF 2 trial was funded by St Jude Medical Inc.
Disclosures
• Dr Verma reports having served on advisory boards for and receiving grant
support from Bayer, Boehringer Ingelheim, Medtronic, Biosense Webster,
and St Jude Medical.
• Dr Betts reports lecture fees and grant support from St Jude Medical.
• Dr Macle reports receiving consulting fees from St Jude Medical, Biosense
Webster, Bristol Meyers Squibb, and Pfizer and grant support from St Jude
Medical and Biosense Webster.
• Dr Morillo reports receiving consulting fees from Boston Scientific,
Medtronic, St Jude Medical, and Boehringer Ingelheim and grant support
from Boston Scientific, Biosense Webster, Pfizer, and Merck.
• Dr Sanders reports having served on advisory boards for and receiving
grant support and lecture fees from Biosense-Webster, Medtronic, St Jude
Medical, Sanofi-Aventis, and Merck; receiving lecture fees and grant
support from Biotronik; and receiving grant support from Sorin.
• Drs. Jiang, Chen, Deisenhofer, and Mantovan do not have any disclosures.
Background
• Catheter ablation is an effective treatment for symptomatic
paroxysmal atrial fibrillation (AF)
• Pulmonary vein isolation (PVI) is considered the cornerstone for
catheter ablation of AF
• Ablation of persistent AF is challenging and typically has less
favorable outcomes compared to paroxysmal AF
Background
• To improve outcomes for persistent AF, guidelines suggest that
“operators should consider more extensive ablation based on
linear lesions or complex fractionated electrograms” in addition to
PV isolation
• Whether more extensive ablation improves outcomes is unclear
Purpose
•
To compare the efficacy of three different AF ablation
strategies in patients with persistent AF:
(1) Pulmonary vein isolation (PVI) alone
(2) PVI plus complex fractionated electrograms (PVI+CFE)
(3) PVI plus linear ablation (PVI+Lines).
Methods - Patients
• 589 patients were recruited from 48 experienced ablation centers
in 12 countries
• Inclusion: symptomatic persistent AF (a sustained episode > 7 days
and < 3 years) refractory to at least one antiarrhythmic drug
undergoing first-time ablation
• Exclusion: paroxysmal AF, sustained AF episode > 3 years, left atrial
diameter > 60 mm
Methods – Trial Design
• Patients were randomized 1:4:4 to the three strategies:
– PVI, PVI+CFE, PVI+Lines
• Patients were blinded to the strategy (single blind)
• Repeat ablation procedures allowed between 3-6 months using
the same randomized strategy as the first ablation
Methods – Ablation Strategy
• PVI = PV antral isolation with endpoint of entrance and exit block
by a circular mapping catheter
• PVI+CFE = PVI followed by mapping and ablation of complex
fractionated electrograms during AF identified by validated
software in the 3D mapping system (Ensite Velocity)
• PVI+Lines = PVI followed by a left atrial roof line and a line along
the mitral valve isthmus with endpoint of bidirectional block
confirmed by pre-specified pacing maneuvers
Methods – Ablation Strategy
CFE strategy
Linear strategy
Methods – Follow-up
• Patients were followed for 18 months
• Visit, ECG and 24 hour Holter at 3, 6, 9, 12 and 18 months
• Weekly TTM transmissions for 18 months
• TTM transmissions every time symptoms felt
– Tele-ECG-Card, Vitaphone, Germany
Outcomes
• Primary Outcome
– Freedom from documented AF episode > 30 seconds after one
ablation procedure with or without antiarrhythmic medications*
• Episodes during initial 3 month “blanking period” excluded from analysis
• Secondary Outcomes
– Freedom from documented AF > 30 seconds after 2 procedures with
or without antiarrhythmic medications
– Freedom from any atrial arrhythmia (AF/AFL/AT) after one or two
procedures
– Procedural time
– Incidence of repeat procedures
– Procedural complications**
– Use of antiarrhythmic medications
* TTMs and recurrences blindly adjudicated, ** blinded events committee adjudication
Results - Baseline Characteristics
Characteristic
PVI
PVI+CFE
PVI+Lines
Age - year
Male sex – n (%)
Ejection fraction (%)
Left atrial diameter (mm)
58 ± 10
52 (78)
55 ± 11
44 ± 6
60 ± 9
213 (82)
57 ± 10
44 ± 6
61 ± 9
196 (76)
57 ± 10
46 ± 6
Time from first AF diagnosis (yrs)
4.3 ± 6.3
4.2 ± 5.0
3.6 ± 4.2
AF burden at Baseline* (hr/month)
83 ± 36
85 ± 33
80 ± 37
Constantly in AF >6 months – n (%)
52 (78)
207 (80)
186 (72)
32 (48)
6 (9)
2 (3)
6 (9)
3 (4)
143 (55)
31 (12)
21 (8)
14 (5)
10 (4)
158 (62)
26 (10)
29 (11)
19 (7)
15 (6)
31 (46)
25 (37)
6 (9)
5 (7)
93 (36)
126 (48)
31 (12)
10 (4)
81 (32)
127 (50)
29 (11)
19 (7)
Medical history – n (%)
Hypertension
Diabetes
Coronary disease
Stroke/TIA
Heart failure
CHADS2 score - n (%)
0
1
2
>2
Results - Ablation characteristics
• 79% of patients presented to EP lab in spontaneous AF
• Successful PV isolation obtained in 97% of all patients (all groups)
• CFE were eliminated in 80% of patients
– 11% not ablated because AF non-inducible after PVI
– 9% all CFE could not be eliminated
• Both lines with block achieved in 74% of patients
– Roof line only 93%
– Mitral line only 75%
Results - Procedural Characteristics
PVI
PVI+CFE
PVI+LINES
p value
166.95 ± 54.83
229.16 ± 83.20
222.56 ± 89.37
<0.0001
Mapping time
(min)
13.89 ± 6.64
18.75 ± 14.01
14.38 ± 7.68
<0.0001
Fluoroscopy
time (min)
29.35 ± 16.21
42.11 ± 21.70
40.91 ± 24.97
0.0003
Procedure
time (min)
Results - Primary Outcome
Documented AF > 30 seconds after one procedure with or without AAD
p=0.15
59%
48%
44%
Results - Secondary Outcomes
PVI
PVI+CFE
PVI+LINES
p value
Freedom from
AF/AFL/AT after
1 procedure
49 %
41 %
37 %
0.15
Freedom from
AF after 2
procedures
72 %
60 %
58 %
0.18
Freedom from
AF/AFL/AT after
2 procedures
60 %
50 %
48 %
0.24
Percentage of
patients still on
AAD at 18 mo
11 %
12 %
12 %
0.35
* AAD = antiarrhythmic drug
Results - Subgroups
Results - Complications
PVI
(n=64)
PVI+CFE
(n=254)
PVI+Lines
(n=250)
Total
(n=568)
Access site hematoma
Access site arteriovenous
fistula or pseudoaneurysm
Pericarditis
2
0
3
5
0
3
3
6
0
1
2
3
Fluid overload
Sedation related
complication
Skin burn
0
1
3
4
0
3
5
8
1
0
0
1
Cardiac tamponade
Transient ischemic attack or
Stroke
Atrial esophageal fistula procedural death
1
0
2
3
0
2
1
3
0
1
0
1
Category
Conclusions
• Largest randomized trial to examine outcomes of catheter
ablation in persistent AF
• Additional CFE or Lines ablation increased procedural time (may
increase risk)
• No benefit in AF reduction when additional substrate ablation
(CFE or Lines) was performed in addition to PVI
• PVI alone achieved freedom from recurrence in about 50% of
patients – comparable to published success rates from
randomized, multicenter trials in paroxysmal AF