Nasr, Deena

Background: Ischemic stroke remains a leading cause of morbidity and mortality worldwide. Cardioembolic sources account for a significant proportion of these events, necessitating accurate identification of underlying structural heart abnormalities. Traditionally, transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) have been utilized for this purpose, although both have limitations. Cardiac computed tomography (CCTA) has emerged as a potential alternative, offering non-invasive imaging with high sensitivity and specificity for detecting intracardiac thrombi. Objective: This study aimed to evaluate the diagnostic yield of CCTA compared to TTE and TEE in detecting high-risk cardioaortic sources of embolism, including left ventricular (LV) thrombus, left atrial (LA) thrombus, valvular thrombus, and ulcerated aortic plaques, in patients with ischemic stroke. Methods: We conducted a retrospective, single-center cohort study at Mayo Clinic, Rochester, MN, including 426 ischemic stroke patients who underwent CCTA within 30 days of stroke onset between March 2019 and June 2023. We compared the diagnostic yields of CCTA, TTE, and TEE in detecting structural cardiac sources of embolism. Results: The overall diagnostic yield of CCTA for detecting high-risk cardioaortic sources was 15.5%. Specifically, CCTA identified LV thrombus in 2.3% of patients, LA thrombus in 4.0%, valvular thrombus in 2.8%, and ulcerated aortic plaques in 7.0%. In comparative analysis, CCTA demonstrated a higher yield than TTE (16.0% vs 3.5%, p < 0.001) and a comparable yield to TEE (25.3% vs 20.7%, p = 0.47) in detecting these sources. Conclusions: CCTA proved to be a viable option for identifying high-risk structural sources of cardioembolism in ischemic stroke patients. Its non-invasive nature, coupled with the ability to perform imaging soon after stroke onset, underscores its clinical utility. However, further prospective and blinded studies are required to validate these findings and fully establish the efficacy of CCTA in this context.

Background: Little is known about the association between intraplaque hemorrhage (IPH) and other features of high-risk carotid atherosclerotic plaques, such as the presence of plaque ulceration, plaque enhancement, and lipid-rich necrotic core (LRNC). This study set out to assess the relationship between IPH and other vulnerable plaque features. Materials and Methods: A retrospective review was done of 102 patients with IPH in one or both of the internal carotid arteries (ICA) on neck MRA between 1/1/2016 and 3/31/2021. IPH was defined as a ≥200% signal intensity of the adjacent sternocleidomastoid muscle on MPRAGE images. All ICA plaques were assessed for the presence or absence of IPH, plaque ulceration, plaque enhancement, and LRNC, as well as IPH volume. IPH volume was measured manually by outlining the region of interest. Results: A total of 102 patients were included, with 88 (86.3%) being male. The average age was 73.5 years (SD = 9.0). Both IPH and LRNC were more commonly seen in the left carotid artery ( p = .018 and p = .047, respectively). For right-sided ICAs, there was a significant association between IPH and LRNC ( p < .0001). Lesions without IPH were more likely to have plaque enhancement than lesions with IPH ( p = .04). For left-sided ICAs, there was also a significant association between the presence of IPH and LRNC ( p < .0001). Conclusions: There is a significant association between the presence of IPH and LRNC. An inverse relationship was found between the presence of IPH and plaque enhancement for right-sided plaques. No associations were found between IPH and plaque ulceration.