title: Myocardial perfusion assessment in humans using steady-pulsed arterial spin labeling.
abstract: OBJECTIVE
  Although arterial spin labeling (ASL) has become a routinely performed method in the rodent heart, its application to the human heart remains challenged by low tissue blood flow and cardiac and respiratory motion. We hypothesized that an alternative steady-pulsed ASL (spASL) method would provide more efficient perfusion signal averaging by driving the tissue magnetization into a perfusion-dependent steady state.
  
  
  METHODS
  We evaluated the feasibility of spASL in the human heart by combining pulsed labeling in the aortic root with a balanced steady state free precession sequence. The spASL scheme was applied to 13 subjects under free breathing. Breathing motion was addressed using retrospective image exclusion based on a contour-based cross-correlation algorithm.
  
  
  RESULTS
  The measured signal with spASL was due to labeled blood. We found that the perfusion signal was larger than that obtained with the earlier flow-sensitive alternating inversion recovery (FAIR) method. Averaged myocardial blood flow (MBF) over four myocardial regions was 1.28 ± 0.36 mL·g(-1) ·min(-1) .
  
  
  CONCLUSIONS
  spASL was able to quantify MBF in healthy subjects under free breathing. Because quantification with ASL is more direct than with first-pass perfusion MRI, it appears particularly suited for pathologies with diffuse microvascular alterations, MBF reserve, and follow-up studies.
authors.affiliation: Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale), 13385, Marseille, France.
authors.forename: Thibaut
authors.initials: T
authors.lastname: Capron
authors.affiliation: Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale), 13385, Marseille, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Troalen
authors.affiliation: Siemens Healthcare France SAS, Saint-Denis, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Robert
authors.affiliation: Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale), 13385, Marseille, France.
authors.forename: Alexis
authors.initials: A
authors.lastname: Jacquier
authors.affiliation: Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale), 13385, Marseille, France.
authors.forename: Monique
authors.initials: M
authors.lastname: Bernard
authors.affiliation: Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale), 13385, Marseille, France.
authors.forename: Frank
authors.initials: F
authors.lastname: Kober
mesh_terms: D000328:Adult; D003326:Coronary Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D012815:Signal Processing, Computer-Assisted; D013113:Spin Labels; D055815:Young Adult
chemical_list: D013113:Spin Labels
keywords: arterial spin labeling; blood flow; cine-ASL; myocardial perfusion; steady state; steady-pulsed