title: Nongated Cardiac Computed Tomographic Angiograms for Detection of Embolic Sources in Acute Ischemic Stroke.
abstract: We assessed the feasibility of obtaining diagnostic quality images of the heart and thoracic aorta by extending thezaxis coverage of a non-ECG-gated computed tomographic angiogram performed in the primary evaluation of acute stroke without increasing the contrast dose.
  
  
  
  Twenty consecutive patients with acute ischemic stroke within the 4.5 hours of symptom onset were prospectively recruited. We increased the longitudinal coverage to the domes of the diaphragm to include the heart. Contrast administration (Omnipaque 350) remained unchanged (injected at 3-4 mL/s; total 60-80 mL, triggered by bolus tracking). Images of the heart and aorta, reconstructed at 5 mm slice thickness in 3 orthogonal planes, were read by a radiologist and cardiologist, findings conveyed to the treating neurologist, and correlated with the transthoracic or transesophageal echocardiogram performed within the next 24 hours.
  
  
  
  Of 20 patients studied, 3 (15%) had abnormal findings: a left ventricular thrombus, a Stanford type A aortic dissection, and a thrombus of the left atrial appendage. Both thrombi were confirmed by transesophageal echocardiography, and anticoagulation was started urgently the following day. None of the patients developed contrast-induced nephropathy on follow-up. The radiation dose was slightly increased from a mean of 4.26 mSV (range, 3.88-4.70 mSV) to 5.17 (range, 3.95 to 6.25 mSV).
  
  
  
  Including the heart and ascending aorta in a routine non-ECG-gated computed tomographic angiogram enhances an existing imaging modality, with no increased incidence of contrast-induced nephropathy and minimal increase in radiation dose. This may help in the detection of high-risk cardiac and aortic sources of embolism in acute stroke patients.
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.). leonard_ll_yeo@nuhs.edu.sg.
authors.forename: Leonard L L
authors.initials: LLL
authors.lastname: Yeo
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Staffan
authors.initials: S
authors.lastname: Holmin
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Tommy
authors.initials: T
authors.lastname: Andersson
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Erik
authors.initials: E
authors.lastname: Lundström
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Anil
authors.initials: A
authors.lastname: Gopinathan
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Er Luen
authors.initials: EL
authors.lastname: Lim
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Benjamin S H
authors.initials: BSH
authors.lastname: Leong
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Win Sen
authors.initials: WS
authors.lastname: Kuan
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Eric
authors.initials: E
authors.lastname: Ting
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Benjamin Y Q
authors.initials: BYQ
authors.lastname: Tan
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Sterling Ellis
authors.initials: SE
authors.lastname: Eide
authors.affiliation: From the Division of Neurology, Department of Medicine, National University Health System, Singapore (L.L.L.Y., B.Y.Q.T.); Department of Clinical Neuroscience (S.H., T.A., E.L.), Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology (S.H., T.A.) and Department of Neurology (E.L.), Karolinska University Hospital, Stockholm, Sweden; Department of Diagnostic Imaging (A.G., E.T., S.E.E.) and Emergency Medicine Department (E.L.L., B.S.H.L., W.S.K.), National University Hospital, National University Health System, Singapore; and Department of Cardiology, National University Heart Centre, Singapore (E.L.K.T.).
authors.forename: Edgar L K
authors.initials: ELK
authors.lastname: Tay
mesh_terms: D000368:Aged; D000784:Aortic Dissection / Q000000981:diagnostic imaging*; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging*; D020517:Atrial Appendage / Q000000981:diagnostic imaging; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology; D000072226:Computed Tomography Angiography / Q000379:methods*; D003287:Contrast Media; D017548:Echocardiography, Transesophageal; D005260:Female; D006331:Heart Diseases / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D007472:Iohexol; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D020521:Stroke / Q000000981:diagnostic imaging* / Q000209:etiology; D013927:Thrombosis / Q000150:complications / Q000000981:diagnostic imaging*
chemical_list: D003287:Contrast Media; D007472:Iohexol
keywords: aorta; computed tomography angiography; embolism; heart; stroke