Clinical factors associated with abandonment of a rate-control or a rhythm-control strategy for the management of atrial fibrillation in the AFFIRM study.
OBJECTIVE
The objective of the current study was to determine the clinical factors that were associated with abandonment of a rate-control or a rhythm-control strategy in patients with atrial fibrillation (AF).


BACKGROUND
Although the AFFIRM Study demonstrated that outcomes are similar with a primary strategy of rate-control or rhythm-control for AF, there may be clinical or demographic factors associated with abandonment of the initial treatment strategy. Knowledge of these risk factors would be useful so that patients may be given appropriate initial therapy and, as appropriate, switched to alternative treatments earlier.


METHODS
Patients in the AFFIRM Study were subdivided into those who were maintained on their initial treatment strategy versus those who abandoned initial treatment strategy for alternative therapies. We determined the clinical and demographic factors associated with change in initial treatment strategy.


RESULTS
At 5 years the original treatment strategy was maintained in 85% of the patients in the rate-control arm versus 62% of those in the rhythm-control arm (P <.0001). Length of the qualifying episode of AF was associated with abandonment of both rhythm-control and rate-control strategies. Antiarrhythmic drug failure before randomization and a history of thyroid disease also were associated with abandonment of rhythm-control. Patients were more likely to maintain rate-control if they already had an implanted pacemaker or if they were older than 75 years, while an ejection fraction <30% was associated with abandonment of the rate-control strategy.


CONCLUSIONS
In patients with AF, rhythm-control strategies are abandoned significantly more often than rate-control strategies. Patients with long durations of AF on presentation or previous antiarrhythmic drug failure might be considered for rate-control as initial treatment.
Curtis
Anne B
AB
Department of Medicine, University of Florida, Gainesville, FL 32610, USA. curtisa@medicine.ufl.edu
Seals
A Allen
AA
Safford
Robert E
RE
Slater
William
W
Tullo
Nicholas G
NG
Vidaillet
Humberto
H
Wilber
David J
DJ
Slee
April
A
D000367:Age Factors; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D004554:Electric Countershock; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models
D000889:Anti-Arrhythmia Agents