PMC7370423_01
Bluish purple ischemic discoloration of the second and fourth toes of the left foot consistent with blue toe syndrome
12959_2020_226_Fig1_HTML.jpg
PMC7370423_01_12959_2020_226_Fig1_HTML.jpg
Fig1
A 65-year-old man presented to the emergency department with two-day history of progressive painful swelling and bluish-purple discoloration of his second and fourth toes of his left foot (Fig. 1) and history of palpitations for a week. Given the high index of suspicion of an intracavitary thrombus in the setting of new-onset AF and progression of the cyanotic toes, the patient was referred to cardiology, where transesophageal echocardiography (TEE) revealed an anomalous LASP and a 7.7 x 3 mm mobile ovoid echodense mass with a narrow stalk attached to the pouch, suggestive of thrombus (Fig. 4, Supplemental Video 1).
Coronal maximum intensity projection (MIP) of lower extremity CT angiography ruling out any significant arterial stenosis
12959_2020_226_Fig2_HTML.jpg
PMC7370423_01_12959_2020_226_Fig2_HTML.jpg
Fig2
The patient underwent immediate thoracic, abdominal, and lower limb contrast-enhanced computed tomographic angiography (CTA), which excluded any proximal thromboembolic source or occlusions in the arterial tree (Fig. 2). Three-dimensional (3D) TEE visualized the LASP containing a mobile thrombus with attachment of its stalk to the interatrial septum (Fig. 6 and Supplemental Video 2).
Chest computed tomographic image demonstrating a filling defect adjacent to the interatrial septum (arrow)
12959_2020_226_Fig3_HTML.jpg
PMC7370423_01_12959_2020_226_Fig3_HTML.jpg
Fig3
This defect was initially suspected to be a cardiac CT artifact in light of the irregular tachyarrhythmia at the time of acquisition, which can generate slow-moving, turbulent blood due to atrial hypokinesia (Fig. 3). 
Transesophageal echocardiogram (TEE) showing LASP opening into the left atrial (LA) cavity and a 7.7 x 3 mm thrombus (arrow), with the site of attachment corresponding to the LASP (2-dimensional TEE images at 60  [a] and biplane TEE image [b] of the interatrial septum). AV, aortic valve; LA, left atrium; RA, right atrium
12959_2020_226_Fig4_HTML.jpg
PMC7370423_01_12959_2020_226_Fig4_HTML.jpg
Fig4
Given the high index of suspicion of an intracavitary thrombus in the setting of new-onset AF and progression of the cyanotic toes, the patient was referred to cardiology, where transesophageal echocardiography (TEE) revealed an anomalous LASP and a 7.7 x 3 mm mobile ovoid echodense mass with a narrow stalk attached to the pouch, suggestive of thrombus (Fig. 4, Supplemental Video 1).
Left atrial septal pouch thrombus seen by color Doppler imaging during TEE at 60  [a] and 120  [b] and simultaneously excluding any probable atrial septal defect
12959_2020_226_Fig5_HTML.jpg
PMC7370423_01_12959_2020_226_Fig5_HTML.jpg
Fig5
There was no evidence of an atrial septal defect on color Doppler flow imaging (Fig. 5), although it showed mild mitral regurgitation.
3D reconstruction of the TEE image of the left side of the interatrial septum to visualize the sessile thrombus (arrows) adherent to the septum and arising from the left atrial septal pouch
12959_2020_226_Fig6_HTML.jpg
PMC7370423_01_12959_2020_226_Fig6_HTML.jpg
Fig6
Three-dimensional (3D) TEE visualized the LASP containing a mobile thrombus with attachment of its stalk to the interatrial septum (Fig. 6 and Supplemental Video 2).
Follow-up TEE showing LASP opening into the left atrium with complete resolution of thrombus after 3 months of oral anticoagulation
12959_2020_226_Fig7_HTML.jpg
PMC7370423_01_12959_2020_226_Fig7_HTML.jpg
Fig7
He remained well 3 months after discharge, with follow-up TEE showing no evidence of thrombus (Fig. 7).
Agitated saline contrast imaging in a follow-up TEE with the bicaval view showing a LASP (arrow) and absence of an atrial septal defect both at rest (a) and with Valsalva maneuver (b)
12959_2020_226_Fig8_HTML.jpg
PMC7370423_01_12959_2020_226_Fig8_HTML.jpg
Fig8
On further imaging with agitated saline contrast, there was no evidence of an atrial septal defect (Fig. 8). 