Prevention of Atrial Fibrillation With ARB After Catheter Ablation
Information source: Queen Elizabeth II Health Sciences Centre
Information obtained from ClinicalTrials.gov on November 03, 2008 Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Atrial Fibrillation; Atrial Flutter
Intervention: Angiotensin Receptor Blocker (valsartan) (Drug)
Phase: Phase 4
Status: Not yet recruiting
Sponsored by: Queen Elizabeth II Health Sciences Centre Official(s) and/or principal investigator(s): Ratika Parkash, MD MSc, Principal Investigator, Affiliation: Dalhousie University/QEII HSC
Overall contact: Ratika Parkash, MD MSc, Phone: 902 473 4474, Email: parkashr@cdha.nshealth.ca
Summary
Atrial fibrillation (AF) is a very common arrhythmia causing many symptoms resulting in
numerous hospitalizations. Catheter ablation is a technique that has evolved significantly
to improve symptomatic recurrences, but does not offer a 100% cure rate. We hypothesize that
the use of angiotensin receptor blockers (ARBs) will reduce the rate of recurrent AF after
catheter ablation for AF or atrial flutter. We plan a randomized clinical trial of an ARB
versus placebo to investigate this. The primary outcome will be time to recurrent AF.
Clinical Details
Official title: A Randomized Clinical Trial of Prevention of Post Ablation Recurrence of Atrial Fibrillation With Angiotensin Receptor Blockers
Study design: Prevention, Randomized, Double-Blind, Placebo Control, Single Group Assignment, Efficacy Study
Primary outcome: Time to recurrent Atrial fibrillation
Secondary outcome: Recurrence of AF at one year
Detailed description:
Background: Atrial fibrillation (AF) is the most common sustained arrhythmia and is
associated with significant morbidity, necessitating treatment. Radiofrequency ablation for
atrial fibrillation/flutter has evolved significantly and is the closest we have come to a
‘cure’ for these dysrhythmias. Recurrence of atrial fibrillation in those who have undergone
radiofrequency ablation as treatment for either atrial flutter (AFl) or AF is up to 40% at
one year. There is significant evidence from animal studies that atrial fibrillation may
have an inflammatory cause and blockade of angiotension II may be beneficial in its
prevention. Recent evidence from clinical trials demonstrate that blockade of angiotensin II
in humans leads to reduction of AF. There is no clinical trial evidence to date of the use
of angiotensin II blockade in patients post radiofrequency ablation for AF or AFl to prevent
recurrent AF.
Objective: We propose to determine if angiotensin receptor blockers (ARBs) prevent
recurrence of atrial fibrillation (AF) in patients who have undergone ablation for AF or AFl
at one year.
Hypothesis: ARBs reduce symptomatic recurrence of atrial fibrillation post radiofrequency
ablation for paroxysmal atrial fibrillation and atrial flutter.
Research Plan:
Study Design. This will be a randomized, double blind, placebo controlled trial in patients
who are post catheter ablation for atrial fibrillation or atrial flutter. Randomization to
either an angiotensin-receptor blocker or placebo will occur within 24 hours after the
ablation procedure.
Study Population. Patients will be included if they have undergone a catheter ablation
procedure for atrial fibrillation or atrial flutter. Those who have undergone a procedure
for atrial flutter must also have a history of prior atrial fibrillation, hypertension, left
ventricular ejection fraction = 40% or age >/= 50 years.
Followup. Patients will be followed at 3 monthly intervals for a minimum duration of one
year.
Outcome Measures. The primary outcome will be time to symptomatic recurrence of atrial
fibrillation. The secondary outcome will be overall burden of atrial fibrillation at one
year. The third outcome measure will be quality of life pre and post ablation. Other
outcome measures include: recurrent ablation therapy, recurrent atrial tachycardia or atrial
flutter, thromboembolic events, changes in biomarkers (CRP, IL-6, ANP, BNP and apelin) from
baseline, to 3 months and 6 months.
Statistical Analysis. Kaplan-Meier analysis of the primary outcome will be performed. A Cox
proportional hazards model will be constructed to assess the effect of variables chosen a
priori on the primary outcome.
Eligibility
Minimum age: 18 Years.
Maximum age: 85 Years.
Gender(s): Both.
Criteria:
Inclusion Criteria:
- Initial catheter ablation for atrial fibrillation that is successful, defined by
demonstration of four pulmonary vein isolation with lack of pulmonary vein electrical
activity on a circular mapping catheter
- Initial catheter ablation for typical atrial flutter this is successful, defined by
demonstration of bidirectional block at the cavotricuspid isthmus
Exclusion Criteria:
- Already on ACEi or ARB therapy, known intolerance to ACEi or ARBs or a known
indication for ACEi/ARB therapy eg. Left ventricular dysfunction, heart failure,
renal dysfunction, coronary artery disease with concomitant risk factors (increased
age, diabetes)
- Creatinine > 160 umol/L
- Unable to give informed consent
- Women of child-bearing potential
- Other noncardiovascular medical condition making 1 year survival unlikely
- Less than 18 years of age
Locations and Contacts
Ratika Parkash, MD MSc, Phone: 902 473 4474, Email: parkashr@cdha.nshealth.ca
QE II Health Sciences Centre, Halifax, Nova Scotia B3H 3A7, Canada
Additional Information
Starting date: July 2007
Ending date: July 2011
Last updated: February 20, 2007
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