title: CT of coronary heart disease: Part 2, Dual-phase MDCT evaluates late symptom recurrence in ST-segment elevation myocardial infarction patients after revascularization.
abstract: OBJECTIVE
  The purpose of the study was to investigate dual-phase MDCT for assessing obstructive lesions and the extent and severity of the subtending myocardium at risk in patients presenting with chest pain syndromes 9 or more months after having undergone revascularization for the treatment of ST-segment elevation myocardial infarction (STEMI).
  
  
  METHODS
  Dual-phase 64-MDCT was performed on 135 patients with recurring chest symptoms 9 months or more after revascularization (mean ± SD, 23 ± 11 months after index invasive angiogram for treatment of STEMI). Obstructive lesions (≥ 50% stenosis) were detected by MDCT angiography and the extent of myocardium at risk was detected by delayed phase 3D myocardium maps. A myocardium at-risk score based on MDCT findings was defined as the extent of myocardium at risk governed by the coronary lesion and weighted by lesion severity. Results were compared with stress-redistribution (201)Tl-SPECT and invasive angiography.
  
  
  RESULTS
  In restenotic, new, progressive, and previously obstructive lesions that are not currently progressive, analysis of assessable segments (1966/2025, 97.1%) obtained true-positive detection rates of 88.1%, 88.6%, 82.9%, and 100%, respectively; false-negative detection rates were 5.3%, 1.6%, 2.9%, and 8.8%. In 124 patients (91.9%) in whom all segments were assessable, the MDCT-based myocardium at-risk score correlated with the SPECT-based summed difference score (SDS) (r = 0.841, p < 0.001). For detecting SPECT-based SDS ≥ 1 and SDS > 3, areas under the receiver operating characteristic curve for the MDCT-based myocardium at-risk score were 0.874 (95% CI, 0.805-0.942) and 0.938 (95% CI, 0.895-0.981), with optimal cutoff values of 2.68 and 5.01, respectively.
  
  
  CONCLUSIONS
  Dual-phase MDCT is useful in detecting different patterns of obstructive lesions and the extent of myocardium at risk as an alternative for therapeutic planning in patients presenting with late symptoms after treatment for acute myocardial infarction.
authors.affiliation: Department of Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, Republic of China.
authors.forename: Kuan-Rau
authors.initials: KR
authors.lastname: Chiou
authors.forename: Nan-Jing
authors.initials: NJ
authors.lastname: Peng
authors.forename: Shih-Hung
authors.initials: SH
authors.lastname: Hsiao
authors.forename: Yi-Luan
authors.initials: YL
authors.lastname: Huang
authors.forename: Chin-Chang
authors.initials: CC
authors.lastname: Cheng
authors.forename: Huay-Ben
authors.initials: HB
authors.lastname: Pan
authors.forename: Ming-Ting
authors.initials: MT
authors.lastname: Wu
mesh_terms: D019540:Area Under Curve; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods*; D016009:Chi-Square Distribution; D003287:Contrast Media; D017023:Coronary Angiography; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007472:Iohexol / Q000031:analogs & derivatives; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000601:surgery*; D009204:Myocardial Revascularization; D011237:Predictive Value of Tests; D012372:ROC Curve; D012008:Recurrence; D012680:Sensitivity and Specificity; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide