title: Spiral tissue phase velocity mapping in a breath-hold with non-cartesian SENSE.
abstract: OBJECTIVE
  Tissue phase velocity mapping (TPVM) is capable of reproducibly measuring regional myocardial velocities. However acquisition durations of navigator gated techniques are long and unpredictable while current breath-hold techniques have low temporal resolution. This study presents a spiral TPVM technique which acquires high resolution data within a clinically acceptable breath-hold duration.
  
  
  METHODS
  Ten healthy volunteers are scanned using a spiral sequence with temporal resolution of 24 ms and spatial resolution of 1.7 × 1.7 mm. Retrospective cardiac gating is used to acquire data over the entire cardiac cycle. The acquisition is accelerated by factors of 2 and 3 by use of non-Cartesian SENSE implemented on the Gadgetron GPU system resulting in breath-holds of 17 and 13 heartbeats, respectively. Systolic, early diastolic, and atrial systolic global and regional longitudinal, circumferential, and radial velocities are determined.
  
  
  RESULTS
  Global and regional velocities agree well with those previously reported. The two acceleration factors show no significant differences for any quantitative parameter and the results also closely match previously acquired higher spatial resolution navigator-gated data in the same subjects.
  
  
  CONCLUSIONS
  By using spiral trajectories and non-Cartesian SENSE high resolution, TPVM data can be acquired within a clinically acceptable breath-hold.
authors.affiliation: NIHR Royal Brompton Cardiovascular Biomedical Research Unit, London, United Kingdom; Imperial College, London, United Kingdom.
authors.forename: Robin
authors.initials: R
authors.lastname: Simpson
authors.forename: Jennifer
authors.initials: J
authors.lastname: Keegan
authors.forename: Peter
authors.initials: P
authors.lastname: Gatehouse
authors.forename: Michael
authors.initials: M
authors.lastname: Hansen
authors.forename: David
authors.initials: D
authors.lastname: Firmin
mesh_terms: D000328:Adult; D062485:Breath Holding; D055424:Cardiac-Gated Imaging Techniques; D005260:Female; D064368:Healthy Volunteers; D006321:Heart / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged
keywords: myocardial mechanics; spiral; tissue phase velocity mapping