Transcript A-4 - Clinical Trial Results

Atrial Fibrillation Ablation vs.
Antiarrhythmic Drugs Trial
A-4 Trial
Presented at
The Heart Rhythm Society Meeting
May 2006
Presented by Dr. Pierre Jais
A-4 Trial: Background
• The goal of this trial was to evaluate catheter
ablation compared with antiarrhythmic drug
therapy among patients with atrial fibrillation
(AF).
www.Clinicaltrialresults.org
Presented at HRS 2006
A-4 Trial: Study Design
112 patient with symptomatic AF > 6 months, ≥ 2 episodes of AF per month,
documentation ≥1 episode of AF, resistant to ≥1 antiarrhythmic drugs from class l or lll
Randomized.
16% female, mean age 51 years, mean follow-up 1 year
Catheter Ablation
n=53


Antiarrhythmic drug therapy with
one of 6 medications
n=59
Primary Endpoint: Absence of AF for ≥ 3 minutes, either symptomatic or documented
Secondary Endpoint: Quality of life, AF burden, number of AF episodes on Holter,
withdrawal of anticoagulant at 1 year
After the primary endpoint was assessed at 3 months, patients could crossover from
medical therapy to ablation, and would be counted as having met the endpoint.
www.Clinicaltrialresults.org
Presented at HRS 2006
A-4 Trial : Principal Findings
• At baseline, the average number of AF episodes
per month was 20, lasting 9 hours.
• Structural heart disease was present in 21% of
patients.
• In the ablation group, the mean procedure duration
was 168 minutes, and an average of 1.8 procedures
were performed.
• In the medical therapy group, amiodarone was first
used in 24 patients, 80% of whom failed therapy.
• After month 3, 70% of patients crossed over to
ablation therapy.
www.Clinicaltrialresults.org
Presented at HRS 2006
A-4 Trial: Primary Endpoint
Patients Free of Arrhythmic Recurrence at 1 Year
p<0.05
75%
75%
50%
25%
7%
0%
Ablation
Group
www.Clinicaltrialresults.org
Medical
Therapy
• At one year,
75% of patients
in the ablation
group and 7%
in the medical
therapy group
were free of
arrhythmic
recurrence
(p<0.05)
Presented at HRS 2006
A-4 Trial: Secondary Endpoint
Interruption of Oral Anticoagulation Therapy
60%
60%
40%
25%
20%
0%
Ablation Group
www.Clinicaltrialresults.org
Medical
Therapy Group
• Oral anticoagulation
therapy was interrupted in
60% of the ablation group
and 25% of the medical
therapy group.
• Among the quality of life
parameters 6 of 8 were
significantly improved in
the ablation group.
• Among all patients treated
with ablation in the trial
(n=90 patients and 155
procedures), including
crossovers, there were 2
cases of tamponade.
Presented at HRS 2006
A-4 Trial: Limitations
• One limitation of the trial was the short
duration of AF needed to meet the primary
endpoint, which was only 3 minutes.
www.Clinicaltrialresults.org
Presented at HRS 2006
A-4 Trial: Summary
• Among patients with atrial fibrillation, catheter ablation
was associated with higher rates of absence of AF
compared with antiarrhythmic drug therapy.
• Additionally, it should be noted that patients in the trial
had all previously failed antiarrhythmic drug therapy,
and results may not be applicable to other AF patients
who had not failed therapy or patients who are not
symptomatic.
www.Clinicaltrialresults.org
Presented at HRS 2006