Non–ECG-gated cardiac CT angiography in acute stroke is feasible and detects sources of embolism

Abstract

Background: A significant portion of cryptogenic stroke is hypothesized to be secondary to cardiac embolism. However, transthoracic echocardiogram is usually delayed after stroke and more detailed cardiac imaging not routinely done. Aims: This study aimed to determine whether non-ECG gated cardiac CT angiography (cCTA) during hyperacute stroke would provide diagnostic quality images and act as an adjunct modality of cardiac imaging to detect sources of emboli. Methods: In this single-centre prospective cohort study, modified Code Stroke imaging was implemented with a 64-slice CT scanner, where the longitudinal axis of CT angiography was extended from the carina to the diaphragm. Primary outcome of image quality, recruitment feasibility, impact on hyperacute time metrics and additional radiation dose were assessed. Secondary outcomes consisted of detection of high-risk cardiac sources of embolism, mediastinal or lung pathology and impact on etiologic classification. Results: One hundred and twenty eligible patients were enrolled, of which 105 (87.5%) had good/moderate quality images for motion artifact and 119 (99.2%) for contrast opacification. Total CT-time, door-to-needle time and door-to-groin puncture time were unchanged with the addition of cCTA. Eighty-nine patients received a final diagnosis of ischemic stroke, of which 12/89 (13.5%) had high-risk cardioembolic findings on cCTA. Incidental findings, such as pulmonary embolism (7/89, 7.9%) and malignancy (6/89, 6.7%), were observed. cCTA led to changes in management for 19/120 (15.8%) of all patients, and reclassification of stroke etiology for 8/89 (9%) of patients. Conclusions: Non- ECG-gated cCTA can be feasibly incorporated into Code Stroke and provide diagnostic quality images without delays in hyperacute time metrics. It can detect high-risk cardiac sources, and other findings impacting patient care. This may help reclassify a subset of cryptogenic stroke cases and improve secondary prevention. Data Availability: Data from this study is available and can be accessed upon request.

Association between Left Atrial Appendage Morphology and Clot Histology in Patients with Embolic Ischemic Stroke: An Exploratory Study

“…Our study has some limitations. First, we used non-electrocardiogram-gated chest CTA (as previously described [ 9 , 23 ]), possibly distorting the LA and LAA anatomy due to motion artifacts. Second, the cardiac scan was exclusively performed in the arterial phase, making it difficult to adequately assess LAA lumen for thrombi and trabeculations in patients with circulatory stasis.…”

Embolic Stroke of Undetermined Source

“…23 Newer approaches such as extended CT angiograms including the LA appendage have demonstrated the presence of intracardiac thrombi or slow LA appendage flow in up to 6.5%-13.5% of patients with ischemic stroke. [24][25][26][27] The DAYLIGHT (Extended Computed Tomography Angiography for the Successful Diagnosis of Cardioaortic Thrombus in Acute Ischemic Stroke and TIA) trial, a single-center RCT, compares the use of extended (6 cm below the carina) CT angiography vs standard CT angiography plus usual stroke workup for the detection of intracardiac thrombi in patients with acute ischemic stroke and transient ischemic attack (TIA) (NCT05522244). Based on its potentially easy adoption, rapid implementation, and the lack of significant complications (e.g., nonsignificant excess radiation or contrast), extended CT angiography is likely to be adopted in the future, further reducing the proportion of patients with ESUS and making the remaining patients with ESUS less likely to benefit from anticoagulation than antiplatelet therapy.…”