title: Relation between left ventricular outflow tract obstruction and left ventricular shape in patients with hypertrophic cardiomyopathy: a cardiac magnetic resonance imaging study.
abstract: BACKGROUND
  Hypertrophic cardiomyopathies (HCM) are often associated with left ventricular (LV) outflow tract obstruction, which can explain symptoms and impact prognosis.
  
  
  OBJECTIVE
  To better understand the mechanisms that link obstruction and LV shape in HCM.
  
  
  METHODS
  Patients with HCM who underwent cardiac magnetic resonance (CMR) imaging were included retrospectively. Obstructive HCM was defined as LV outflow gradient more than 30 mm Hg at rest by transthoracic echocardiography. The LV shape and mitral angle were assessed by CMR. Results were compared with control subjects.
  
  
  RESULTS
  Mean LV-mitral angle was smaller in patients with obstructive HCM (n=29) than in patients with non-obstructive HCM (n=15) or control subjects (n=15) (80 ± 5° vs 87 ± 7° [P=0.0002] and 89 ± 2° [P<0.0001]). Mean mitral papillary muscles angle was greater in patients with non-obstructive HCM than in patients with obstructive HCM or control subjects (136 ± 17° vs 123 ± 16° [P=0.007] and 118 ± 10° [P=0.002]). Patients with non-obstructive HCM had a greater mean LV-aortic root angle than patients with obstructive HCM or control subjects (139 ± 6° vs 135 ± 7° [P=0.04] and 133 ± 7° [P=0.03]).
  
  
  CONCLUSIONS
  There is a relation between morphological and functional parameters in HCM within which the mitral valve is probably part of pathophysiogenesis.
authors.affiliation: Department of Cardiology, Rangueil University Hospital, 1, avenue Jean-Poulhès, TSA 50032, 31059 Toulouse cedex 9, France; Cardiac Imaging Center, University Hospital of Toulouse, Toulouse, France.
authors.forename: Romain
authors.initials: R
authors.lastname: Martin
authors.forename: Olivier
authors.initials: O
authors.lastname: Lairez
authors.forename: Nicolas
authors.initials: N
authors.lastname: Boudou
authors.forename: Simon
authors.initials: S
authors.lastname: Méjean
authors.forename: Thibault
authors.initials: T
authors.lastname: Lhermusier
authors.forename: Nicolas
authors.initials: N
authors.lastname: Dumonteil
authors.forename: Matthieu
authors.initials: M
authors.lastname: Berry
authors.forename: Thomas
authors.initials: T
authors.lastname: Cognet
authors.forename: Pierre
authors.initials: P
authors.lastname: Massabuau
authors.forename: Meyer
authors.initials: M
authors.lastname: Elbaz
authors.forename: Hervé
authors.initials: H
authors.lastname: Rousseau
authors.forename: Michel
authors.initials: M
authors.lastname: Galinier
authors.forename: Didier
authors.initials: D
authors.lastname: Carrié
mesh_terms: D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D015150:Echocardiography, Doppler; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014694:Ventricular Outflow Obstruction / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology / Q000503:physiopathology
keywords: CMR; Cardiac magnetic resonance imaging; Cardiomyopathie hypertrophique; Géométrie ventriculaire gauche; HCM; Hypertrophic cardiomyopathy; Imagerie par résonance magnétique cardiaque; LV; LVARa; LVMa; Left ventricular outflow tract obstruction; Left ventricular shape; MPMa; MRI; Obstruction intraventriculaire gauche; SD; cardiac magnetic resonance; hypertrophic cardiomyopathy; left ventricular; left ventricular–aortic root angle; left ventricular–mitral angle; magnetic resonance imaging; mitral papillary muscles angle; standard deviation