THROMBOEMBOLIC
RISK IN ATRIAL FLUTTER. THE FLASIEC (FLUTTER ATRIALE SOCIETA ITALIANA DI
ECOGRAFIA CARDIOVASCOLARE) MULTICENTRE STUDY.
Corrado
G, et al. Eur Heart J 2001 Jun;22(12):1042-51.
AIMS:
Patients with atrial flutter are believed to be at lower risk of
thromboembolism than patients with atrial fibrillation. However, the incidence
of atrial thrombi and the need for anticoagulation in patients with atrial
flutter is not well established.
METHODS
AND RESULTS: A prospective observational multicentre study was undertaken to
assess the frequency of atrial thrombi and spontaneous echocontrast and the
prevalence for aortic complex atherosclerotic lesions in a cohort of unselected
patients with atrial flutter. We evaluated 134 patients (102 male, aged 70+/-9
years); exclusion criteria were history of atrial fibrillation, rheumatic
mitral valve disease and mitral mechanical prosthesis. The median of atrial
flutter duration was 33 days. Twelve patients had been taking warfarin for more
than 7 days. One hundred and twenty-four patients (94%) underwent a
transoesophageal echocardiogram, which revealed left atrial appendage thrombi
in two patients (1.6%) and right atrial thrombi in one patient (1%). At least
moderate left atrial echocontrast was found in 16/124 patients (13%). Complex
atherosclerotic aortic plaques were detected in 10 patients (8%). Atrial
flutter conversion was attempted in 93/134 patients (69%). At the 1-month follow-up,
two patients experienced a thromboembolic event following restoration of sinus
rhythm.
CONCLUSIONS:
Atrial thrombi and echocontrast, and complex aortic atherosclerotic plaques are
relatively uncommon in patients with atrial flutter. Post-cardioversion
embolism was observed in two patients in our study population.
COMMENTS:
The two patients who had thromboembolic complications both had negative
echocardiograms. Furthermore, there were 15 patients who had a history of
thrombus prior to developing atrial flutter. This would suggest that the risk
for atrial thrombi is low, and may not necessitate the risks associated with
long-term anticoagulation.