Last Updated: 2001-07-10 12:33:12 EDT (Reuters Health)
המידע באדיבות מדיקונטקסט
By Will Boggs, MD
WESTPORT, CT (Reuters Health) – Early cardioversion of atrial fibrillation (AF) facilitated by transesophageal echocardiography (TEE) to exclude atrial thrombi is safe and reduces the recurrence of AF, according to a report in the June 15th issue of The American Journal of Medicine.
Several reports suggest that the duration of AF before cardioversion determines the likelihood of reestablishment and maintenance of sinus rhythm, the authors explain, but whether early cardioversion aided by TEE promotes sustained sinus rhythm remains largely untested.
Dr. Warren J. Manning, from Beth Israel Deaconess Medical Center and Harvard Medical School in Boston, and colleagues attempted TEE in 539 patients with AF of only a few weeks' duration and attempted cardioversion in 463 patients without atrial thrombi.
Nearly 90% of the patients in whom no atrial thrombi were seen were successfully converted to sinus rhythm during their initial admission, the authors report. Most were converted by direct current cardioversion.
Among the patients in whom cardioversion was attempted, 93.2% had therapeutic heparin or warfarin anticoagulation, the results indicate, and 71% of these patients were discharged on warfarin at the discretion of their primary physician.
Only one patient with a "negative" TEE developed a clinical systemic thromboembolic event (a brachial artery thrombus requiring surgical removal) during the month after cardioversion, the researchers note, but repeated TEE failed to reveal an atrial source of thrombi.
Recurrent AF in the year after cardioversion affected 57.9% of all patients, though the incidence of recurrence was 29% lower in patients whose AF duration was less than 3 weeks at the time of cardioversion, the report indicates.
"In this [study], we demonstrate reduced recurrence of atrial fibrillation during the first year postcardioversion among patients undergoing cardioversion with atrial fibrillation of <3 weeks' duration, a time interval that is not compatible with conventional therapy of 3 to 4 weeks of warfarin prophylaxis before cardioversion," the authors conclude.
"Given the data suggesting that patients with a duration of AF of <3 weeks have enhanced maintenance of sinus rhythm at 1 year," Dr. Manning told Reuters Health, "we would suggest the TEE-guided early-cardioversion approach for any patient with a duration of AF of <3 weeks. Our study was focused on in-patients, but the data are likely applicable to a more general population," he said.
"Patients with a thrombus on TEE have a relatively poor prognosis," Dr. Manning added. "Though not proven by this study, patients with a thrombus on the initial TEE should undergo a follow-up TEE to document thrombus resolution prior to undergoing elective cardioversion."
Am J Med 2001;110:694-702.
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