title: Acute coronary occlusion in non-ST-elevation acute coronary syndrome: outcome and early identification by strain echocardiography.
abstract: OBJECTIVE
  To compare infarct size and left ventricular ejection fraction in patients with non-ST-elevation myocardial infarction (NSTEMI) with and without acute coronary occlusions, and determine if myocardial strain by speckle-tracking echocardiography can identify acute occlusions in patients presenting with non-ST-elevation acute coronary syndrome (NSTE-ACS).
  
  
  METHODS
  111 patients with suspected NSTE-ACS were enrolled shortly after admittance. Echocardiographic measurements were performed a median of 1 h (interquartile range 0.5-4) after admittance, and coronary angiography 36 ± 21 h after onset of symptoms. Territorial longitudinal and circumferential strain was calculated based on the perfusion territories of the three major coronary arteries in a 16-segment model of the left ventricle, and compared with traditional echocardiographic parameters. Long-term follow-up was by echocardiography and contrast-enhanced magnetic resonance imaging (ceMRI).
  
  
  RESULTS
  Patients with NSTEMI due to acute coronary occlusion had higher peak troponin T than patients with NSTEMI without acute occlusions (4.9 ± 4.7 vs 0.9 ± 1.1 μg/l, p<0.001), larger infarct size by ceMRI (13 ± 8% vs 3 ± 3%, p<0.001) and poorer left ventricular ejection fraction (48 ± 6% vs 57 ± 6%, p<0.001) at follow-up. Territorial circumferential strain was the best parameter for predicting acute coronary occlusion. A territorial circumferential strain value >-10.0% had 90% sensitivity, 88% specificity and area under the curve=0.93 for identification of acute occlusions.
  
  
  CONCLUSIONS
  Patients with NSTEMI due to acute coronary occlusions develop larger infarcts and more impaired left ventricular function than patients with NSTEMI without occlusions, regardless of infarct-related territory. Territorial circumferential strain by echocardiography enables very early identification of acute coronary occlusions in patients with NSTE-ACS and may be used for detection of patients requiring urgent revascularisation.
authors.affiliation: Department of Medicine, Sørlandet Hospital, Arendal 4809, Norway.
authors.forename: Bjørnar
authors.initials: B
authors.lastname: Grenne
authors.forename: Christian
authors.initials: C
authors.lastname: Eek
authors.forename: Benthe
authors.initials: B
authors.lastname: Sjøli
authors.forename: Thomas
authors.initials: T
authors.lastname: Dahlslett
authors.forename: Michael
authors.initials: M
authors.lastname: Uchto
authors.forename: Per K
authors.initials: PK
authors.lastname: Hol
authors.forename: Helge
authors.initials: H
authors.lastname: Skulstad
authors.forename: Otto A
authors.initials: OA
authors.lastname: Smiseth
authors.forename: Thor
authors.initials: T
authors.lastname: Edvardsen
authors.forename: Harald
authors.initials: H
authors.lastname: Brunvand
mesh_terms: D054058:Acute Coronary Syndrome / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D000368:Aged; D015415:Biomarkers / Q000097:blood; D017023:Coronary Angiography; D054059:Coronary Occlusion / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D042241:Early Diagnosis; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology / Q000503:physiopathology; D013318:Stroke Volume / Q000502:physiology; D020107:Troponin T / Q000097:blood
chemical_list: D015415:Biomarkers; D020107:Troponin T