AFFIRM: Atrial Fibrillation Followup Investigation of Rhythm Management

1
AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management

• Purpose
• To compare the rhythm-control and rate-control
  strategies for reducing overall mortality in
  patients with atrial fibrillation.
• Reference
• The Atrial Fibrillation Follow-up Investigation
  of Rhythm Management (AFFIRM) Investigators. A
  comparison of rate control and rhythm control in
  patients with atrial fibrillation. N Engl J Med
  200234718251833.

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AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management- TRIAL DESIGN
-

• Design
• Randomized, multicentre comparison of
  rate-control and rhythm-control treatment
  strategies.
• Patients
• 4060 patients who were aged 65 years old or who
  had other risk factors for stroke or death. Of
  these, 70.8 were hypertensive, and 38.2 had
  coronary heart disease.
• Follow-up and primary endpoint
• The primary endpoint was overall mortality,
  and the mean follow-up was 3.5 years.

3
AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management- TRIAL DESIGN
continued -

• Treatment
• Patients were assigned to either the
  rhythm-control or rate-control strategy groups
  and were allowed to switch groups if necessary.
• Rhythm-control strategy group
• Antiarrhythmic drugs as prescribed by the
  physician, with cardioversion if required.
  Continuous anticoagulation therapy with warfarin
  was encouraged but could be stopped after sinus
  rhythm was maintained for at least 4 days.
• Rate-control strategy group
• Beta-blockers, calcium channel blockers
  (verapamil and diltiazem), or a combination of
  these drugs, with continuous anticoagulation
  therapy with warfarin.
• Other therapeutic considerations
• If both treatment strategies failed,
  patients were considered for non-pharmacological
  therapy.

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AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management - TRIAL
DESIGN continued -
Baseline characteristics
Rhythm control
Rate control
(n2027)
(n2033)
Mean age years
69.8
69.7
Female sex no. ()
823 (40.6)
771 (37.9)
Predominant cardiac diagnosis no. ()
Coronary artery disease
497 (24.5)
562 (27.6)
Hypertension
1045 (51.6)
1018 (50.1)
464 (22.8)
History of congestive heart failure no. ()
475 (23.4)
Duration of qualifying atrial fibrillation 2
days no. ()
1402 (69.0)
1406 (69.4)
Any pre-randomization failure of
anantiarrhythmic drug no. ()
364 (18.0)
349 (17.2)
The AFFIRM Investigators. N Eng J Med
200234718251833.
5
AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management - RESULTS -

• Primary endpointMore deaths occurred in the
  rhythm-control group than in the rate-control
  group (hazard ratio, 1.18 95 confidence
  interval, 0.991.41 p0.07).
• There was no significant statistical difference
  in mortality rates between the groups.
• Rate of crossover between groups
• 549 patients in the rhythm-control group
  switched to the rate-control group. Of these, a
  further 61 crossed back to the rhythm-control
  group by the end of the study.
• Morality rates in patient sub-populations
• In comparison with the rate-control strategy,
  the rhythm-control strategy was associated with
  higher rates of death in patients who were older,
  in patients who had coronary artery disease, and
  in patients without congestive heart failure.

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AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management - RESULTS
continued -
Cumulative mortality from any cause in the
rhythm-control and rate-control groups








No. of deaths Rhythm control Rate control
Number (percent)
The AFFIRM Investigators. N Eng J Med
200234718251833.
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AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management - RESULTS
continued -
Hazard ratios for death in pre-specified patient
sub-populations

65 yr
50
2 days
The AFFIRM Investigators. N Eng J Med
200234718251833.
8
AFFIRM Atrial Fibrillation Follow-up
Investigation of Rhythm Management - SUMMARY -

• Although there was a trend towards increased
  mortality in the rhythm-control group versus the
  rate-control group (p0.08), there was no
  significant statistical difference in mortality
  rates between the two strategies.
• The crossover rate was significantly greater
  among patients in the rhythm-control strategy
  group.
• The rate-control strategy should be considered
  as the primary approach in managing atrial
  fibrillation.
• Continuous anticoagulation therapy is warranted
  in all patients with atrial fibrillation and risk
  factors for stroke.