title: Quantitating aortic regurgitation by cardiovascular magnetic resonance: significant variations due to slice location and breath holding.
abstract: OBJECTIVE
  Compare variability in flow measurements by phase contrast MRI, performed at different locations in the aorta and pulmonary artery (PA) using breath-held (BH) and free-breathing (FB) sequences.
  
  
  METHODS
  Fifty-seven patients with valvular heart disease, confirmed by echocardiography, were scanned using BH technique at 3 locations in the ascending aorta (SOV = sinus of Valsalva, STJ = sinotubular junction, ASC = ascending aorta at level of right pulmonary artery) and 2 locations in PA. Single FB measurement was obtained at STJ for aorta. Obtained metrics (SV = stroke volume, FV = forward volume, BV = backward volume, RF = regurgitant fraction) were evaluated separately for patients with aortic regurgitation (AR, n = 31) and mitral regurgitation (n = 26).
  
  
  RESULTS
  No difference was noted between the two measurements in the PA. Significant differences were noted in measured SV at different aortic locations. SV measurements obtained at ASC correlated best with the measurements obtained in the PA. Strongest correlation of AR was measured at the STJ.
  
  
  CONCLUSIONS
  Measurements of flow volumes by phase contrast MRI differ depending on slice location. When using stroke volumes to calculate pulmonary to systemic blood flow ratio (Qp/Qs), ASC should be used. For quantifying aortic regurgitation, measurement should be obtained at STJ.
  
  
  CONCLUSIONS
  • Aortic regurgitation can be accurately measured by MRI. • Aortic regurgitation measurement by MRI varies according to the location where measured. • Aortic regurgitation can also be measured by MRI without breath hold.
authors.affiliation: Department of Radiology, University of Rochester Medical Center, Rochester, NY, USA. toabhic@gmail.com.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Chaturvedi
authors.affiliation: Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA.|University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Christian
authors.initials: C
authors.lastname: Hamilton-Craig
authors.affiliation: Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Cawley
authors.affiliation: Department of Radiology, Straub Clinic and Hospital, Honolulu, HI, USA.
authors.forename: Lee M
authors.initials: LM
authors.lastname: Mitsumori
authors.affiliation: Department of Cardiology, University of Washington School of Medicine, Seattle, WA, USA.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Otto
authors.affiliation: Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA.
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Maki
mesh_terms: D000328:Adult; D000368:Aged; D001022:Aortic Valve Insufficiency / Q000175:diagnosis*; D062485:Breath Holding; D004452:Echocardiography; D005260:Female; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000175:diagnosis*
keywords: Aortic regurgitation; Free breathing; Magnetic resonance imaging; Phase contrast; Quantification