P wave dispersion and short-term vs. late atrial fibrillation recurrences after cardioversion.
BACKGROUND
P wave dispersion has been previously suggested as a potential tool for predicting the risk of recurrence of atrial fibrillation after electrical cardioversion. We investigated whether different P wave dispersion values are associated with recurrence of atrial fibrillation in the short (< or =1 month after cardioversion) and longer term.


METHODS
In 37 patients with long-lasting persistent atrial fibrillation (mean duration 21 +/- 36 months) with (n = 19) or without (n = 18) amiodarone pretreatment as antiarrhythmic prophylaxis, maximum and minimum P wave duration and P wave dispersion were measured 1 min after internal cardioversion.


RESULTS
P wave dispersion was lower in patients with amiodarone pretreatment (28.3 +/- 9.5 vs. 21.9 +/- 7.3 ms, P = 0.029). The subgroups of patients with recurrence of atrial fibrillation at 1 month or in the long-term did not differ from the rest of the study sample regarding age, sex, atrial fibrillation duration, left atrial dimensions or ejection fraction. P wave dispersion was significantly higher in patients with short-term atrial fibrillation recurrence (< or = 1 month) than in the rest of the population. Furthermore, P wave dispersion values >25 ms were associated with a higher short-term relapse rate. No significant relation was present in the long-term.


CONCLUSIONS
Our results suggest that P wave dispersion analysis immediately after internal cardioversion may help predict short-term recurrences of atrial fibrillation. These findings may be related to different mechanisms and predisposing factors for short-term and late recurrences. The long-term predictive value of serial evaluations of P wave dispersion during follow-up deserves investigation.
Boriani
Giuseppe
G
Institute of Cardiology, University of Bologna, Azienda Ospedaliera S. Orsola-Malpighi, Italy. cardio1@almadns.unibo.it
Diemberger
Igor
I
Biffi
Mauro
M
Camanini
Claudia
C
Valzania
Cinzia
C
Corazza
Ivan
I
Martignani
Cristian
C
Zannoli
Romano
R
Branzi
Angelo
A
D000368:Aged; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000628:therapy; D006328:Cardiac Catheterization; D004554:Electric Countershock / Q000379:methods; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012189:Retrospective Studies; D055502:Secondary Prevention; D013997:Time Factors
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone