Thromboembolism in Patients With Atrial Fibrillation With and Without Left Atrial Thrombus Documented by Transesophageal Echocardiography

Abstract

The incidence of cerebrovascular events (CVEs) was investigated in 95 consecutive patients with atrial fibrillation (AF) with left atrial thrombus (LAT) diagnosed by transesophageal echocardiography (TEE) and in 131 age- and sex-matched AF patients without LAT. Compared with patients without LAT, patients with LAT had a larger left atrial diameter (49 versus 44 mm, P < 0.0001), a lower left ventricular ejection fraction (40% versus 50%, P < 0.0001), a higher prevalence of spontaneous echocardiographic contrast (88% versus 25%, P < 0.001), a reduced left atrial appendage emptying velocity (0.25 versus 0.41 cm/s, P < 0.0001), and less use of antiarrhythmic drugs (61% versus 76%, P = 0.03). Before TEE, the prevalence of prior CVE was higher in LAT patients (20%) compared with patients without LAT (8%) (P = 0.01). Fifty-four of 95 LAT patients (57%) and 81 of 131 non-LAT patients (62%) were on warfarin before TEE. The incidence of prior CVE in LAT patients without warfarin (32%) was higher than that in non-LAT patients without warfarin (10%) (P = 0.02). The mortality rate in LAT patients with an international normalized ratio (INR) >or= 2.0 (42%) was higher than that in patients without LAT and an INR >or= 2.0 (11%) (P < 0.001). Fifty-one of 95 LAT patients (54%) underwent repeat TEE before cardioversion (48 patients received warfarin therapy). The thrombus resolved in 40 of 51 patients (78%) after the first TEE. There was no significant difference in INR between the patients with persistent and resolved LAT. AF patients with persistent LAT had a higher incidence of CVE (45%) than the patients with resolved LAT (5%) (P = 0.003). We suggest that patients with LAT be treated with warfarin to maintain an INR between 2.5 and 3.5 rather than between 2.0 and 3.0 because they are at a high risk for new thromboembolism.

Resolution of left atrial appendage thrombus with apixaban

“…The optimal therapeutic range for anticoagulation with warfarin in the prevention of thromboembolic events with non-valvular AF patients extends over INR values of 2.0 to 3.0 [6,7]. It has been reported that major bleeding is observed only at INR values above 2.5 on anticoagulation with warfarin [1].…”

Oral anticoagulation and left atrial thrombi resolution in nonrheumatic atrial fibrillation or flutter: A systematic review and meta‐analysis

“…The flowchart of the systematic review is depicted in Figure . Of the 8,468 articles screened, 17 articles were selected for the final analyses . The initial and follow‐up data of the articles included in the final analyses are listed in Table and in Table , respectively.…”

“…Two articles from Creighton University had overlapping populations, but both were retained given different suitability for VKA and warfarin analyses . The study by Nair et al.…”

“…The study by Nair et al. was used for the VKA analysis given a larger sample size . From Shen et al., 29 subjects who started warfarin after detection of LAT were used in the warfarin‐specific analysis given low risk of bias .…”

Measurement of left atrial appendage size by transesophageal echocardiography

“…We consider that LAA size is an important factor that determines LAA function. Although transesophageal echocardiography allows the LAA structure to be assessed with high accuracy, some technical problems remain [3,4]. On the other hand, LAA filling detected by 64-slice multidetector computed tomography (64-MDCT) has been reported as a useful modality for imaging the LAA structure [5,6].…”