title: The delay of contrast arrival in magnetic resonance first-pass perfusion imaging: a novel non-invasive parameter detecting collateral-dependent myocardium.
abstract: OBJECTIVE
  To establish the regional delay of contrast arrival in magnetic resonance perfusion imaging (MRPI) for the detection of collateral-dependent myocardium in patients with coronary artery disease.
  
  
  METHODS
  Observational study, case series; single centre, university hospital.
  
  
  METHODS
  30 patients with coronary artery disease and collateral-dependent myocardium and 17 healthy volunteers.
  
  
  METHODS
  Resting and hyperaemic (adenosine) MRPI was used to determine the delay time (Deltat(d)) of contrast arrival between the left ventricle and collateral-dependent or antegradely perfused myocardium, and myocardial perfusion (MP, ml/min/g).
  
  
  RESULTS
  In healthy volunteers, mean (SD) Deltat(d) at rest and during hyperaemia were 0.8 (0.4) and 0.3 (0.3) s, and MP was 1.14 (0.21) and 4.23 (1.12) ml/min/g. In patients Deltat(d) in antegradely perfused vs collateral-dependent myocardium was 0.9 (0.7) vs 1.7 (1.0) s at rest (p<0.001), and 0.4 (0.3) vs 1.1 (0.6) s (p<0.001) during hyperaemia. MP was 1.12 (0.11) and 0.98 (0.28) ml/min/g (p = NS) at rest and 2.46 (0.85) vs 1.86 (0.91) ml/min/g (p<0.01) during hyperaemia. Receiver operating characteristics analysis showed the best sensitivity and specificity of 90% and 83% for hyperaemic Deltat(d) of >0.6 s (area under the curve (AUC) = 0.89) to detect collateral-dependent myocardium, while resting Deltat(d) (AUC = 0.77) and perfusion (AUC = 0.69 at rest or 0.70 during hyperaemia) were less accurate.
  
  
  CONCLUSIONS
  MRPI-derived hyperaemic delay of contrast arrival detects collateral-dependent myocardium with high sensitivity and specificity. Perfusion was less sensitive, emphasising the clinical role of Deltat(d) in non-invasive detection of collateral-dependent myocardium.
authors.affiliation: Department of Medicine and Radiology, University of Munich, Munich, Germany. olaf.muehling@med.uni-muenchen.de
authors.forename: O M
authors.initials: OM
authors.lastname: Muehling
authors.forename: A
authors.initials: A
authors.lastname: Huber
authors.forename: C
authors.initials: C
authors.lastname: Cyran
authors.forename: S O
authors.initials: SO
authors.lastname: Schoenberg
authors.forename: M
authors.initials: M
authors.lastname: Reiser
authors.forename: G
authors.initials: G
authors.lastname: Steinbeck
authors.forename: M
authors.initials: M
authors.lastname: Nabauer
authors.forename: M
authors.initials: M
authors.lastname: Jerosch-Herold
mesh_terms: D003097:Collateral Circulation / Q000502:physiology*; D003287:Contrast Media / Q000493:pharmacokinetics*; D017023:Coronary Angiography; D003327:Coronary Disease / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000592:standards; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA