title: Cardiac systolic rotation and contraction before and after valve replacement for aortic stenosis: a myocardial tagging study using MR imaging.
abstract: OBJECTIVE
  Aortic stenosis leads to the derangement of cardiac function and contraction mode because of chronic pressure overload that is relieved after surgical valve replacement. The purpose of this study was to determine the changes in left ventricular systolic rotation and contraction using MR tagging in patients with aortic stenosis before and after surgical valve replacement compared with age-matched healthy volunteers.
  
  
  METHODS
  Twelve patients with aortic stenosis were examined with an electrocardiographically triggered two-dimensional tagging sequence at 1.5 T before and 12 months after surgical valve replacement for the evaluation of wall function of the apical, mid ventricular, and basal levels. Eight healthy volunteers in the same age group served as the control group.
  
  
  RESULTS
  Before surgery, all patients showed a significant increase of apical rotation (22.2 degrees +/- 5.9 degrees vs 10.3 degrees +/- 2.5 degrees, p < 0.0001) and overall left ventricular torsion (25.1 degrees +/- 6.6 degrees vs 14.5 degrees +/- 3.7 degrees, p < 0.001); basal rotation was not significantly different (-2.9 degrees +/- 2.1 degrees vs -4.2 degrees +/- 1.9 degrees, p = not significant) compared with the volunteer group. Apical rotation and torsion were negatively correlated with left ventricular mass (r = -0.73, p < 0.01, and r = -0.61, p < 0.05, respectively) and end-diastolic volume (r = -0.73, p < 0.01 and r = -0.64, p < 0.03, respectively). One year after surgery, basal rotation was reduced in the patients with aortic stenosis compared with the patients in the control group (-1.9 degrees +/- 1.8 degrees, p < 0.01). In comparison with preoperative values, apical rotation (14.2 degrees +/- 3.6 degrees, p < 0.01) also decreased but was still elevated, and this resulted in a normalization of left ventricular torsion (16.1 degrees +/- 3.7 degrees, p < 0.01).
  
  
  CONCLUSIONS
  Surgical valve replacement for aortic stenosis leads to normalization of the left ventricular torsion 1 year after surgery. Pressure overload before surgery is associated with an increase of systolic left ventricular wringing motion, possibly serving as a compensatory mechanism. This mechanism declines with increasing left ventricular hypertrophy and dilatation.
authors.affiliation: Institut für Röntgendiagnostik & Medizinische Klinik, Universität Würzburg, Josef-Schneider-Strasse 2, D-97080 Würzburg, Germany.
authors.forename: Joern J W
authors.initials: JJ
authors.lastname: Sandstede
authors.forename: Thorsten
authors.initials: T
authors.lastname: Johnson
authors.forename: Kerstin
authors.initials: K
authors.lastname: Harre
authors.forename: Meinrad
authors.initials: M
authors.lastname: Beer
authors.forename: Siegfried
authors.initials: S
authors.lastname: Hofmann
authors.forename: Thomas
authors.initials: T
authors.lastname: Pabst
authors.forename: Werner
authors.initials: W
authors.lastname: Kenn
authors.forename: Wolfram
authors.initials: W
authors.lastname: Voelker
authors.forename: Stefan
authors.initials: S
authors.lastname: Neubauer
authors.forename: Dietbert
authors.initials: D
authors.lastname: Hahn
mesh_terms: D000328:Adult; D000368:Aged; D001024:Aortic Valve Stenosis / Q000503:physiopathology* / Q000601:surgery; D004562:Electrocardiography; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D013599:Systole; D016277:Ventricular Function, Left