title: Impact of global left ventricular afterload on left ventricular function in asymptomatic severe aortic stenosis: a two-dimensional speckle-tracking study.
abstract: OBJECTIVE
  The present study sought to assess the effect of global left ventricular (LV) afterload on LV myocardial systolic function in patients with aortic stenosis (AS) and preserved LV ejection fraction.
  
  
  RESULTS
  We prospectively examined the LV myocardial deformation (i.e. longitudinal, radial, and circumferential) by two-dimensional speckle tracking in 173 patients with asymptomatic severe AS. Thirty-eight patients (22%) had low flow as determined by a low stroke volume index (<or=35 mL/m(2)). By multivariable analysis, four variables emerged as independently associated with low-flow AS: peak Ea velocity (P = 0.01), left atrial area index (P = 0.017), global LV afterload (P = 0.024), and circumferential myocardial deformation (P = 0.04). Forty-nine patients (28%) had an increased global LV afterload (>or=5 mmHg mL/m(2)). Systemic arterial compliance (P = 0.001), circumferential myocardial deformation (P = 0.024), and left atrial area index (P = 0.04) were independently associated with increased global LV load in multivariable analysis. Of note, LV ejection fraction was not identified as a determinant of low flow or increased afterload.
  
  
  CONCLUSIONS
  In asymptomatic patients with severe AS, LV ejection fraction markedly underestimates the extent of myocardial systolic impairment. Intrinsic myocardial dysfunction is particularly common in patients with increased global LV afterload, and especially in the subset of patients with low-flow AS.
authors.affiliation: Department of Cardiology, University Hospital, Domaine Universitaire du Sart Tilman, B.35-4000 Liège, Belgium. plancellotti@chu.ulg.ac.be
authors.forename: Patrizio
authors.initials: P
authors.lastname: Lancellotti
authors.forename: Erwan
authors.initials: E
authors.lastname: Donal
authors.forename: Julien
authors.initials: J
authors.lastname: Magne
authors.forename: Kim
authors.initials: K
authors.lastname: O'Connor
authors.forename: Marie L
authors.initials: ML
authors.lastname: Moonen
authors.forename: Bernard
authors.initials: B
authors.lastname: Cosyns
authors.forename: Luc A
authors.initials: LA
authors.lastname: Pierard
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000473:pathology; D002302:Cardiac Output; D004452:Echocardiography / Q000295:instrumentation* / Q000379:methods; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000473:pathology; D006439:Hemodynamics; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D020097:Natriuretic Peptide, Brain / Q000097:blood; D011446:Prospective Studies; D012372:ROC Curve; D012720:Severity of Illness Index; D013318:Stroke Volume; D016277:Ventricular Function, Left
chemical_list: D020097:Natriuretic Peptide, Brain