title: Single-breathhold, four-dimensional, quantitative assessment of LV and RV function using triggered, real-time, steady-state free precession MRI in heart failure patients.
abstract: OBJECTIVE
  To validate a novel, real-time, steady-state free precession (SSFP), single-breathhold technique for the assessment of left ventricular (LV) and right ventricular (RV) function in heart failure patients.
  
  
  METHODS
  A total of 20 heart failure patients (mean age 59 +/- 17 years) underwent scanning with our new, real-time, spiral SSFP sequence in which each cardiac phase was acquired in 118 msec at a resolution of 1.8 x 1.8 mm. Each cardiac slice (1-cm thick) was automatically advanced based on a cardiac trigger, allowing complete coverage of the heart in a single breathhold. The patients also underwent LV and RV assessment with the gold standard: multiple breathhold, cardiac-gated, segmented k-space strategy. LV and RV end-systolic volume (ESV) and end-diastolic volume (EDV) and LV mass were compared between the two imaging techniques.
  
  
  RESULTS
  The new real-time strategy was highly concordant with the gold standard technique in the assessment of LVEDV (r = 0.98), LVESV (r = 0.98), RVESV (r = 0.86), RVEDV (r = 0.91), LVMASS (r = 0.95), RVEF (r = 0.70), and LVEF (r = 0.94). The mean bias (95% confidence interval [CI]) for each parameter is LVEDV: 10.6 cc (cm(3)) (3.8-17.4 cc), LVESV: -0.8 cc (-5.3 to 3.7 cc), RVEDV: 3.7 cc (-5.6 to 13.2 cc), RVESV: -3.1 cc (-11.1 to 4.9 cc), LVMASS: 26 g (12.4-39.8 g), RVEF: -2.9% (1.3 to -7.2 %), LVEF: 1.9% (5 to -1.1%). In addition, data acquisition was only nine +/- two seconds with the real-time strategy vs. 312 +/- 41 seconds for the standard technique.
  
  
  CONCLUSIONS
  In patients with heart failure, real-time, spiral SSFP allows rapid and accurate assessment of RV and LV function in a single-breath hold. Using the same strategy, increased temporal resolution will allow real-time assessment of cardiac wall motion during stress studies.
authors.affiliation: Division of Cardiovascular Medicine, Stanford University Hospital, Stanford, California 94305, USA. gnarayan@stanford.edu
authors.forename: Girish
authors.initials: G
authors.lastname: Narayan
authors.forename: Krishna
authors.initials: K
authors.lastname: Nayak
authors.forename: John
authors.initials: J
authors.lastname: Pauly
authors.forename: Bob
authors.initials: B
authors.lastname: Hu
mesh_terms: D006333:Heart Failure / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged