title: Cardiac imaging improves risk stratification in high-risk patients undergoing surgical revascularization.
abstract: OBJECTIVE
  In patients with ischaemic left ventricular dysfunction, multivessel disease and dominance of necrotic myocardium, perioperative mortality due to coronary artery bypass grafting is still a rather unclear issue. The aim of this study was to analyse the impact of different imaging variables in predicting perioperative mortality.
  
  
  METHODS
  We selected a group of 259 patients who had preoperatively been defined as 'high-risk patients' and who showed a mostly necrotic myocardium as detected by thallium-201 myocardial scintigraphy.
  
  
  RESULTS
  Mean ejection fraction was 0.26 +/- 0.07. In a 16-segment model, the mean number of scintigraphic necrotic myocardial segments was 5.07 +/- 1.09, echocardiographic end-diastolic diameter was 29.41 +/- 2.38 mm/m2 and wall motion score index was 2.29 +/- 0.19. Perioperative mortality increased along with the increase in the number of necrotic segments: 5/105 (5%), 4/63 (6%), 8/52 (15%) and 8/39 (20%) patients with four, five, six and seven necrotic segments, respectively. The analysis of additional variables in survived vs. deceased patients demonstrated a significant difference in echocardiographic end-diastolic diameter (27 +/- 8 vs. 31.9 +/- 1.9 mm/m2, P < 0.001) and in wall motion score index (2.2 +/- 0.1 vs. 2.4 +/- 0.2, P < 0.001).
  
  
  CONCLUSIONS
  In high-risk patients, the extension of scintigraphic myocardial scar has a significant impact on perioperative mortality. For similar values of ejection fraction at rest, additional imaging variables, such as echocardiographic end-diastolic diameter and wall motion score index, may contribute to select those patients in whom mortality may exceed 15%.
authors.affiliation: Nuclear Cardiology, CNR Institute of Clinical Physiology, Via Moruzzi 1, 56124 Pisa, Italy. gimelli@ifc.cnr.it
authors.forename: Alessia
authors.initials: A
authors.lastname: Gimelli
authors.forename: Antonio
authors.initials: A
authors.lastname: L'Abbate
authors.forename: Mattia
authors.initials: M
authors.lastname: Glauber
authors.forename: Andrea
authors.initials: A
authors.lastname: Ripoli
authors.forename: Assuero
authors.initials: A
authors.lastname: Giorgetti
authors.forename: Paolo
authors.initials: P
authors.lastname: Marzullo
mesh_terms: D016009:Chi-Square Distribution; D017023:Coronary Angiography; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000601:surgery*; D009204:Myocardial Revascularization / Q000379:methods*; D009336:Necrosis; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012372:ROC Curve; D015635:Radionuclide Ventriculography / Q000379:methods*; D018570:Risk Assessment; D013794:Thallium Radioisotopes; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000601:surgery*
chemical_list: D013794:Thallium Radioisotopes