Diagnostic Yield of ECG-Gated Cardiac CT in theAcute Phase of Ischemic Stroke vsTransthoracic Echocardiography

Abstract

Background:Guidelines recommend echocardiography to screen for structural sources of cardioembolism in patients with ischemic stroke. Cardiac CT is a promising alternative as a first-line screening method. We aimed to determine whether cardiac CT, acquired during the initial stroke imaging protocol, has a higher yield for detecting high-risk cardio-aortic sources of embolism than transthoracic echocardiography (TTE).Methods:We performed a prospective, single center, observational cohort study and included consecutive adult patients with acute ischemic stroke who underwent ECG-gated cardiac CT during the initial stroke imaging protocol. Patients also underwent routine stroke work-up, including TTE. The main outcome was the proportion of patients with a predefined high-risk cardio-aortic source of embolism on cardiac CT versus TTE in patients undergoing both investigations.Results:Between May 2018 and November 2020, 774 patients with a suspected ischemic stroke underwent hyperacute cardiac CT. We excluded 228 patients with a diagnosis other than ischemic stroke and 94 because they did not provide informed consent. Therefore, 452 patients (59.3% male, median age 72) were included. The median additional scan time of cardiac CT was 6 (interquartile range 5–7) minutes with poor scan quality in only 3%.In total, 350/452 (77.4%) patients underwent TTE, 99 of which were performed in an outpatient setting. Reasons for not undergoing TTE were: death (33, 7.3%) and TTE being too burdensome to perform in the outpatient setting (69, 15.3%). A high-risk cardio-aortic source of embolism was detected in 40/350 (11.4%) patients on CT, compared to 17/350 (4.9%) on TTE (odds ratio 5.60, 95%CI: 2.28–16.33). Cardiac thrombus was the most frequent finding (7.1% vs 0.6%). The diagnostic yield of cardiac CT in the full study population was 54/452 (12.2%). Among 175 patients with cryptogenic stroke after routine work-up, cardiac CT identified a cause of the stroke in 11 (6.3%).Discussion:Cardiac CT acquired in the acute phase of ischemic stroke is technically feasible and has a superior diagnostic yield compared to TTE for the detection of high-risk sources of embolism. Cardiac CT may be considered as an alternative to TTE to screen for cardioembolism.

Detection of Cardioembolic Sources With Nongated Cardiac Computed Tomography Angiography in Acute Stroke: Results From the ENCLOSE Study

“…The yield of cardiac CTA was higher than echocardiography in our study and in a recent ECG-gated CTA study. 28 To minimize motion artifacts, cardiac CTA is usually acquired with ECG gating but requires a separate scan costing extra iodine contrast agent, radiation dose, and time in a situation where time is brain in AIS compared with nongated CTA. 29 A disadvantage of nongated CTA could be that metric measurements such as left atrial enlargement, which has been associated with stroke, are unreliable as compared with measurements on ECG-gated CTA.…”

Cardiac thrombi detected by CT in patients with acute ischemic stroke: A substudy of Mind the Heart

“…This study is a sub study of the Mind the Heart study. 14 , 17 Mind the Heart was a prospective single-center cohort study performed in Amsterdam UMC, a comprehensive stroke center in the Netherlands. The aim of the study was to determine whether cardiac CT acquired in the acute phase of stroke has a higher diagnostic yield for structural sources of embolism compared to transthoracic echocardiography and may therefore be a suitable screening method in patients with ischemic stroke.…”

“…The diagnostic yield of CT for cardiac thrombi ranges from 10%–24% in cohort studies, 9 – 13 and is higher compared to TTE. 14 Previous studies have described worse outcome after stroke in patients with atrial fibrillation-related stroke, 15 , 16 but there is a paucity of studies reporting on functional outcome in ischemic stroke patients with a cardiac thrombus. We aimed to compare characteristics, functional outcome and risk of recurrent stroke in ischemic stroke patients with and without a cardiac thrombus detected on cardiac CT.…”

Incremental value of the combined brain-cardiac CT protocol on prediction of atrial fibrillation after stroke

“…5 Recent studies showed that the implementation of cardiac CT angiography (CCTA) in the acute stroke imaging protocol led to the diagnosis of LAA thrombus in 11% of confirmed ischemic strokes 6 and had a superior diagnostic yield compared to transthoracic echocardiography for the detection of high-risk cardio-aortic sources of embolism. 7 We thus hypothesized that CCTA parameters of atrial cardiopathy at admission for ischemic stroke could be used for the early identification of patients at high risk of developing AFDAS during follow-up.…”