title: Duplex ultrasound in the early diagnosis of acute mesenteric ischemia: a longitudinal cohort multicentric study.
abstract: OBJECTIVE
  Acute mesenteric ischemia (AMI) is a life-threatening condition requiring time-dependent treatment; thus, early recognition may improve outcomes. We hypothesized that clinician-performed mesenteric vessels duplex ultrasound (DUS) could facilitate early identification of patients with AMI in high-risk patients presenting with abdominal pain.
  
  
  METHODS
  This was a single-operator, observational, prospective cohort study. Patients aged at least 65 presenting to Emergency Departments with acute abdominal pain and no clear diagnosis after an initial work-up were enrolled. All patients underwent multidetector computed tomography and these findings provided the reference standard in this study. DUS of the celiac artery and superior mesenteric artery (SMA) were obtained to measure the peak systolic velocity (PSV) and were performed within 24 h of admission. PSVs outside the normal range were considered to indicate AMI.
  
  
  RESULTS
  Of 49 patients identified, 47 were consented to enrollment and diagnostic images were obtained in 45 (96%). Fifteen patients (33%) had AMI (six occlusive, nine nonocclusive disease). Among these, 12 (80%) had abnormal DUS velocities. SMA PSV showed a sensitivity of 78.57% [95% confidence interval (CI): 49.2-95.34], a specificity of 64.52% (95% CI: 45.37-80.77), a positive predictive value of 50% (95% CI: 28.22-71.78), and a negative predictive value of 86.96% (95% CI: 66.41-97.22) for AMI. DUS had a sensitivity of 100%, a specificity of 64%, and a negative predictive value of 100% for occlusive AMI. Assessment of celiac artery PSV did not improve diagnostic performance.
  
  
  CONCLUSIONS
  In this single-operator pilot study, mesenteric vessel DUS was performed successfully in the Emergency Department, with a high proportion of diagnostic images obtained. A normal SMA PSV was associated with a low risk of occlusive AMI.
authors.affiliation: aEmergency Department, Whipps Cross University Hospital bEmergency Department, Queen Mary University London, Barts Health NHS Trust, London, UK cEmergency Medicine Department dEmergency Department, University Hospital of Siena, Siena, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Sartini
authors.forename: Guido
authors.initials: G
authors.lastname: Calosi
authors.forename: Carolina
authors.initials: C
authors.lastname: Granai
authors.forename: Tim
authors.initials: T
authors.lastname: Harris
authors.forename: Fulvio
authors.initials: F
authors.lastname: Bruni
authors.forename: Marcello
authors.initials: M
authors.lastname: Pastorelli
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D002445:Celiac Artery / Q000000981:diagnostic imaging; D015331:Cohort Studies; D000072226:Computed Tomography Angiography / Q000379:methods; D042241:Early Diagnosis; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D007558:Italy; D008137:Longitudinal Studies; D008297:Male; D017538:Mesenteric Artery, Superior / Q000000981:diagnostic imaging*; D065666:Mesenteric Ischemia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods*