Detection of high intensity transient signals (HITS) in the carotid artery was performed as a screening for 463 employees of a general company (mean age 47.2 years). HITS was detected in the common carotid artery for 5 minutes with a paste type ultrasonic probe taped to the neck. As a result, it was detected in 17 out of 463 (3.7%), 4 out of 126 under 40 years old (3.2%), and 13 out of 337 over 40 years old (3.9%). Of the 17 patients with carotid HITS detected, 1 had valvular heart disease, 2 had arrhythmias, and 2 had atrial fibrillation, including paroxysmal atrial fibrillation. In addition, the background factors of carotid artery HITS were not significantly different in age, gender, blood pressure, diabetes, hypertension, lipid abnormalities, etc., but were significantly different in heart disease, arrhythmia, and atrial fibrillation including paroxysmal. Therefore, most carotid HITS in general company examination were considered to be due to arrhythmia such as atrial fibrillation.
We reported three cases with cardioembolic stroke after left atrial appendage (LAA) occlusion. First case is 72 years old man with right hemiparesis. His MRI showed acute ischemic lesion in left MCA territory. He was performed endovascular treatment and got complete recanalization. He had a history of his mitral valve replacement and LAA occlusion due to his atrial fibrillation and mitral valve regurgitation. His transesophageal echocardiography (TEE) pointed out fistula between left atrium (LA) and LAA. The second case is 74 years old man who got operation of LAA closure 6 years ago. He suffered from right hemiparesis caused by his MCA M2 occlusion. We examined TEE and found a fistula between LA and LAA. The third case is 72 years old man with right thalamus infarction. TEE showed the very small fistula between LA and LAA detected only by Doppler color flow imaging. It has been reported that subsequent LAA closure associated with cardiac surgery reduces the incidence of stroke. However, incomplete LAA closure was known as cause of stroke. Therefore, we considered it is necessary to perform TEE to observe LAA on the TEE even after LAA closure.
An 80-year-old woman was diagnosed with acute middle cerebral artery occlusion and underwent mechanical thrombectomy (MT). The iatrogenic arterial dissection formed in the cervical internal carotid artery during MT. This was observed because there was no stenosis or extravasation. On follow-up, a pseudoaneurysm was observed; therefore, stent-assisted coil embolization was performed to prevent rupture and thromboembolism. Although computed tomography angiography was not useful for post-treatment evaluation due to metal artifacts, transoral carotid ultrasonography (TOCU) confirmed that the lumen of the stent was well delineated and there was no blood flow within the coil-filled mass. TOCU is therefore useful in the diagnosis and post-treatment evaluation of pseudoaneurysms.