title: Integrated SPECT/CT for assessment of haemodynamically significant coronary artery lesions in patients with acute coronary syndrome.
abstract: OBJECTIVE
  Early risk stratification in patients with non-ST elevation acute coronary syndromes (NSTE-ACS) is important since the benefit from more aggressive and costly treatment strategies is proportional to the risk of adverse clinical events. In the present study we assessed whether hybrid single photon emission computed tomography (SPECT)/coronary computed tomography angiography (CCTA) technology could be an appropriate tool in stratifying patients with NSTE-ACS.
  
  
  METHODS
  SPECT/CCTA was performed in 90 consecutive patients with NSTE-ACS. The Thrombolysis in Myocardial Infarction risk score (TIMI-RS) was used to classify patients as low- or high-risk. Imaging was performed using SPECT/CCTA to identify haemodynamically significant lesions defined as >50% stenosis on CCTA with a reversible perfusion defect on SPECT in the corresponding territory.
  
  
  RESULTS
  CCTA demonstrated at least one lesion with >50% stenosis in 35 of 40 high-risk patients (87%) as compared to 14 of 50 low-risk patients (35%; TIMI-RS<3; p<.0001). Of the 40 high-risk and 50 (16%) low-risk TIMI-RS patients, 16 (40%) and 8 (16%), respectively, had haemodynamically significant lesions (p=0.01). Patients defined as high-risk by a high TIMI-RS, a positive CCTA scan or both (n=45) resulted in a sensitivity of 95%, specificity of 49%, PPV of 35% and NPV of 97% for having haemodynamically significant coronary lesions. Those with normal perfusion were spared revascularization procedures, regardless of their TIMI-RS.
  
  
  CONCLUSIONS
  Noninvasive assessment of coronary artery disease by SPECT/CCTA may play an important role in risk stratification of patients with NSTE-ACS by better identifying the subgroup requiring intervention.
authors.affiliation: Department of Cardiology, Rambam Health Care Campus and the B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Shmuel
authors.initials: S
authors.lastname: Rispler
authors.forename: Doron
authors.initials: D
authors.lastname: Aronson
authors.forename: Sobhi
authors.initials: S
authors.lastname: Abadi
authors.forename: Ariel
authors.initials: A
authors.lastname: Roguin
authors.forename: Ahuva
authors.initials: A
authors.lastname: Engel
authors.forename: Rafael
authors.initials: R
authors.lastname: Beyar
authors.forename: Ora
authors.initials: O
authors.lastname: Israel
authors.forename: Zohar
authors.initials: Z
authors.lastname: Keidar
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D023381:Endpoint Determination; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009203:Myocardial Infarction / Q000150:complications; D049268:Positron-Emission Tomography; D018570:Risk Assessment; D014057:Tomography, X-Ray Computed