title: Subcoronary versus supracoronary aortic stenosis. An experimental evaluation.
abstract: BACKGROUND
  Valvular aortic stenosis is the most common cause of left ventricular hypertrophy due to gradually increasing pressure work. As the stenosis develop the left ventricular hypertrophy may lead to congestive heart failure, increased risk of perioperative complications and also increased risk of sudden death. A functional porcine model imitating the pathophysiological nature of valvular aortic stenosis is very much sought after in order to study the geometrical and pathophysiological changes of the left ventricle, timing of surgery and also pharmacological therapy in this patient group. Earlier we developed a porcine model for aortic stenosis based on supracoronary aortic banding, this model may not completely imitate the pathophysiological changes that occurs when valvular aortic stenosis is present including the coronary blood flow. It would therefore be desirable to optimize this model according to the localization of the stenosis.
  
  
  METHODS
  In 20 kg pigs subcoronary (n = 8), supracoronary aortic banding (n = 8) or sham operation (n = 4) was preformed via a left lateral thoracotomy. The primary endpoint was left ventricular wall thickness; secondary endpoints were heart/body weight ratio and the systolic/diastolic blood flow ratio in the left anterior descending coronary. Statistical evaluation by oneway anova and unpaired t-test.
  
  
  RESULTS
  Sub- and supracoronary banding induce an equal degree of left ventricular hypertrophy compared with the control group. The coronary blood flow ratio was slightly but not significantly higher in the supracoronary group (ratio = 0.45) compared with the two other groups (subcoronary ratio = 0.36, control ratio = 0.34).
  
  
  CONCLUSIONS
  A human pathophysiologically compatible porcine model for valvular aortic stenosis was developed by performing subcoronary aortic banding. Sub- and supracoronary aortic banding induce an equal degree of left ventricular hypertrophy. This model may be valid for experimental investigations of aortic valve stenosis but studies of left ventricular hypertrophy can be studied equally well by graduated constriction of the ascending aorta.
authors.affiliation: Department of Anaesthesiology and Intensive Care, Aarhus University Hospital, Skejby, Brendstrupgaardsvej 100, 8200 Aarhus N, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Sorensen
authors.forename: J Michael
authors.initials: JM
authors.lastname: Hasenkam
authors.forename: Henrik
authors.initials: H
authors.lastname: Jensen
authors.forename: Erik
authors.initials: E
authors.lastname: Sloth
mesh_terms: D000818:Animals; D001011:Aorta / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D001783:Blood Flow Velocity; D001835:Body Weight; D003331:Coronary Vessels / Q000503:physiopathology; D004195:Disease Models, Animal; D005260:Female; D006321:Heart / Q000033:anatomy & histology; D017379:Hypertrophy, Left Ventricular / Q000209:etiology / Q000473:pathology; D009929:Organ Size; D011446:Prospective Studies; D011897:Random Allocation; D013552:Swine; D013908:Thoracotomy