title: Understanding left ventricular outflow obstruction: anatomoechocardiographic correlation.
abstract: OBJECTIVE
  Echocardiography is a valuable noninvasive technique for identifying the site and type of obstruction in the left ventricular outflow tract. Knowledge of the morphological details of each type of obstruction is the basis for correct interpretation of the diagnostic images and clinical decisions.
  
  
  METHODS
  This study was undertaken to provide improved understanding of the anatomy of left ventricular outflow obstruction with corresponding side-by-side echocardiographic images. Specimens were part of the collection of the Department of Embryology of the Instituto Nacional de Cardiología "Ignacio Chávez," Mexico City, Mexico. Twenty-eight patients were studied by echocardiography, and 22 specimens with different types of left ventricular outflow tract obstruction were analyzed.
  
  
  RESULTS
  Echocardiographic characteristics: Eighteen (64.3%) patients were women and 10 (35.7%) men. Three had fibrous rings, 19 with obstructive asymmetric septal hypertrophic cardiomyopathy, 1 with posterior displacement of the infundibular septum, 2 with accessory mitral valve tissue, 2 with anomalous insertion of mitral valve chordae tendineae, and 1 with malposition of the mitral valve and papillary muscles. Anatomic characteristics: Twelve had fibrous ring, 2 asymmetric septal hypertrophic cardiomyopathy, 2 posterior displacement of the infundibular septum, 1 ectopic mitral tissue, 1 anomalous insertion of mitral valve chordae tendineae in the ventricular septum, 3 malposition of the mitral valve and papillary muscles, and 1 subaortic infundibulum.
  
  
  CONCLUSIONS
  The anatomoechocardiographic correlation clearly demonstrates the mechanism of subaortic obstruction. The comparison with corresponding echocardiographic images of different subaortic obstruction types is potentially quite valuable in enhancing the echocardiographer's understanding especially of complex subaortic obstruction.
authors: Department of Echocardiography in Outpatient Clinic, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City, Mexico. niesza2001@hotmail.com
authors: Nilda
authors: N
authors: Espinola-Zavaleta
authors: Luis
authors: L
authors: Muñóz-Castellanos
authors: María Guadalupe
authors: MG
authors: Herrera
authors: Candace
authors: C
authors: Keirns
mesh_terms: D000293:Adolescent; D000328:Adult; D001021:Aortic Valve / Q000473:pathology; D002815:Chordae Tendineae / Q000473:pathology; D019560:Echocardiography, Three-Dimensional; D005260:Female; D006346:Heart Septum / Q000473:pathology; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000473:pathology; D014694:Ventricular Outflow Obstruction / Q000000981:diagnostic imaging*