title: Comparison of atrial fibrillation recurrence rates after successful electrical cardioversion in patients with hyperthyroidism-induced versus non-hyperthyroidism-induced persistent atrial fibrillation.
abstract: Hyperthyroidism-induced atrial fibrillation (AF) often spontaneously reverts to sinus rhythm after the return of euthyroid state, but a significant number of patients remain in persistent AF, which requires electrical cardioversion. The long-term outcome of hyperthyroidism-induced persistent AF after successful cardioversion remains unclear. The study group consisted of 58 patients with hyperthyroidism-induced persistent AF (mean age 57 +/- 2 years, 72% men) who had undergone successful electrical cardioversion. The AF recurrence rate was prospectively studied and compared with age- and gender-matched controls with persistent AF of nonthyroid origins. After a 24-month follow-up period, 34 patients (59%) had developed AF recurrence, significantly fewer than among controls (83%) (hazard ratio 0.64, 95% confidence interval 0.39 to 0.97, p = 0.04). Cox regression analysis showed that long AF duration was the only predictor of AF recurrence in patients with hyperthyroidism-induced persistent AF. In conclusion, hyperthyroidism-induced persistent AF carries a lower recurrence rate after conversion to sinus rhythm than non-hyperthyroidism-induced persistent AF, and early electrical cardioversion should be considered.
authors.affiliation: Department of Medicine, Queen Mary Hospital, Hong Kong, China.
authors.forename: Chung-Wah
authors.initials: CW
authors.lastname: Siu
authors.forename: Man-Hong
authors.initials: MH
authors.lastname: Jim
authors.forename: Xuehua
authors.initials: X
authors.lastname: Zhang
authors.forename: Yap-Hang
authors.initials: YH
authors.lastname: Chan
authors.forename: Vincent
authors.initials: V
authors.lastname: Pong
authors.forename: Jeanette
authors.initials: J
authors.lastname: Kwok
authors.forename: Annie W C
authors.initials: AW
authors.lastname: Kung
authors.forename: Chu-Pak
authors.initials: CP
authors.lastname: Lau
authors.forename: Hung-Fat
authors.initials: HF
authors.lastname: Tse
mesh_terms: D001281:Atrial Fibrillation / Q000209:etiology* / Q000628:therapy*; D004554:Electric Countershock; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications*; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D013997:Time Factors; D016896:Treatment Outcome