title: Isovolumic cardiac contraction on high-temporal-resolution cine MR images: study in heart failure patients and healthy volunteers.
abstract: OBJECTIVE
  To prospectively implement high-temporal-resolution cine magnetic resonance (MR) imaging protocol to compare cardiac preejection contraction (PEC) and prefilling relaxation (PFR) times between heart failure (HF) patients and healthy control subjects and to assess accuracy of PEC times to stratify HF patients, with ejection fraction (EF) and New York Heart Association (NYHA) symptom class as reference standards.
  
  
  METHODS
  Following institutional review board approval of this HIPAA-compliant study and written informed consent, 18 healthy volunteers (10 women, eight men; mean age, 43 years +/- 14 [standard deviation]) and 18 HF patients (five women, 13 men; mean age, 49.8 years +/- 3) were imaged (breath-hold true fast imaging with steady-state precession, with temporal resolution of 5.6 msec at 1.5 T). By using left ventricular (LV) outflow tract acquisition, PEC phase was defined as time at QRS trigger to immediately before aortic valve opening. PFR was defined as time from initial aortic valve closure to immediately before mitral valve opening. Group means were compared (unpaired Student t test). Accuracy of PEC parameters in stratifying participants with severe systolic HF on the basis of EF and NYHA symptom class was assessed (receiver operating characteristic curve analysis).
  
  
  RESULTS
  Compared with control subjects, HF patients had prolonged mean PEC time (40.4 msec +/- 11.8 vs 91.3 msec +/- 26, P < .001) and mean PFR time (68.3 msec +/- 26.8 vs 103.7 msec +/- 41.8, P < .01). PEC time correlated with global EF (r = -0.73, P < .001) and LV mass (r = 0.69, P < .001). For identification of patients with severe LV systolic dysfunction (EF <or= 35%), PEC time was highly accurate (area under the curve [AUC], 0.900 [P < .001]). For identification of patients with moderate-to-severe HF symptoms (NYHA class > 2), PEC time had good accuracy (AUC, 0.875 [P < .001]).
  
  
  CONCLUSIONS
  It is feasible to assess isovolumic PEC and PFR phases of the cardiac cycle with high-frame-rate cine MR images, and PEC time is a surrogate measure of moderate-to-severe systolic HF.
authors.affiliation: Department of Medicine, Division of Cardiology, David Geffen School of Medicine at UCLA, 10945 Leconte Ave, Peter Ueberroth Blvd, Room 3371D, Los Angeles, CA 90025, USA. hdinh@post.harvard.edu
authors.forename: Howard V
authors.initials: HV
authors.lastname: Dinh
authors.forename: Juan
authors.initials: J
authors.lastname: Alvergue
authors.forename: James
authors.initials: J
authors.lastname: Sayre
authors.forename: John S
authors.initials: JS
authors.lastname: Child
authors.forename: Vibhas S
authors.initials: VS
authors.lastname: Deshpande
authors.forename: Gerhard
authors.initials: G
authors.lastname: Laub
authors.forename: J Paul
authors.initials: JP
authors.lastname: Finn
mesh_terms: D000328:Adult; D019540:Area Under Curve; D016022:Case-Control Studies; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006334:Heart Function Tests; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D011446:Prospective Studies; D012372:ROC Curve