[Detection of Signs of Thrombus Formation in Patients With Typical Atrial flutter]

to assess rate of detection of markers of thrombi formation and to determine whether transthoracic echocardiography data or clinical characteristics predict severe left atrial appendage [LAA] dysfunction (low LAA velocity, severe spontaneous echo contrast [SEC], LAA thrombus) in patients with typical atrial flutter (AFI).

Consecutive 406 patients (299 with atrial fibrillation [AFib] and 107 with AFI) underwent transesophageal echocardiography before cardioversion. Mean age was 59.3 years, mean CHA2DS2-VASc score--1.86, mean LAA velocity--37.02 cm/s.

Compared with patients with AF those with AFI had lower rate of detection of markers of thrombi formation (p < 0.05). Among patients with AFI 1.8% had SEC grade 4+, 7.4%--LAA velocity ≤ 25 cm/s. LAA thrombus was found in 2.8 and 8.1% of patients with AFI and AFib, respectively. Prevalence of thrombi in left ventricular (LV) cavity was significantly higher in patients with AFI (3.13 vs. 0.3% in patients with AFib, p = 0.02). In patients with AFI systolic LV dysfunction was the main and ost significant predictor of severe LAA dysfunction and presence LV thrombus.

AFI associated high risk of embolic events is primarily determined by its adverse effect on LV function.