title: A novel coronary angiography index (DILEMMA score) for prediction of functionally significant coronary artery stenoses assessed by fractional flow reserve: A novel coronary angiography index.
abstract: BACKGROUND
  Angiographic evaluation of diameter stenosis has modest predictive value for functionally significant coronary artery stenoses as assessed by fractional flow reserve (FFR). Lesion length and assessment of area of myocardium at risk (Bypass Angioplasty Revascularization Investigation [BARI] Myocardial Jeopardy Index [MJI]) subtended by the stenotic coronary arteries are also predictors of functionally significant coronary artery stenoses. We sort to assess the diagnostic accuracy of DILEMMA score, which combines minimal lumen diameter (MLD), lesion length, and BARI MJI in prediction of significantly reduced FFR (≤0.8).
  
  
  METHODS
  We assessed patients who underwent coronary angiography and FFR. Lesion length and MLD were assessed by quantitative coronary angiography. Estimation of area of myocardium at risk subtended by coronary stenoses was performed using the BARI MJI.
  
  
  RESULTS
  A total of 296 patients (age 64 ± 10.6 years, 68% male, 497 vessels) were included. DILEMMA score was significantly higher in vessels with significant FFR, 6.09 ± 3.23 versus 3.84 ± 2.99 (P < .001). In the derivation cohort, the optimism-adjusted Harrell c statistic for DILEMMA score was 0.82 compared with 0.76 for BARI MJI, 0.75 for lesion length, and 0.7 for MLD. In the validation cohort, the c-statistic for DILEMMA score, BARI MJI, lesion length, and MLD was 0.88, 0.77, 0.81, and 0.72, respectively. The DILEMMA score was a better predictor of FFR ≤0.8 compared with MLD, lesion length, and BARI MJI individually (P < .001, P < .02, and P < .045, respectively) on Bonferroni-adjusted pairwise comparison.
  
  
  CONCLUSIONS
  DILEMMA score, taking into account MLD, lesion length, and BARI MJI, may have incremental predictive value beyond the individual indices alone for detecting functionally significant coronary artery stenoses.
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia. Electronic address: drdenniswong@yahoo.com.au.
authors.forename: Dennis T L
authors.initials: DT
authors.lastname: Wong
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia.
authors.forename: Om
authors.initials: O
authors.lastname: Narayan
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia.
authors.forename: Brian S H
authors.initials: BS
authors.lastname: Ko
authors.affiliation: Population Health Research Institute, McMaster University, Hamilton, Ontario, Canada; South Australian Health & Medical Research Institute, Adelaide, South Australia, Australia.
authors.forename: Darryl P
authors.initials: DP
authors.lastname: Leong
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia.
authors.forename: Sujith
authors.initials: S
authors.lastname: Seneviratne
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia.
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Potter
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia.
authors.forename: James D
authors.initials: JD
authors.lastname: Cameron
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia.
authors.forename: Ian T
authors.initials: IT
authors.lastname: Meredith
authors.affiliation: Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, Victoria, Australia.
authors.forename: Yuvaraj
authors.initials: Y
authors.lastname: Malaiapan
mesh_terms: D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index