title: Low-flow, low-gradient severe aortic stenosis despite normal ejection fraction is associated with severe left ventricular dysfunction as assessed by speckle-tracking echocardiography: a multicenter study.
abstract: BACKGROUND
  Low-flow low-gradient (LFLG) is sometimes observed in severe aortic stenosis (AS) despite normal ejection fraction, but its frequency and mechanisms are still debated. We aimed to describe the characteristics of patients with LFLG AS and assess the presence of longitudinal left ventricular dysfunction in these patients.
  
  
  RESULTS
  In a multicenter prospective study, 340 consecutive patients with severe AS and normal ejection fraction were studied. Longitudinal left ventricular function was assessed by 2D-strain and global afterload by valvulo-arterial impedance. Patients were classified according to flow and gradient: low flow was defined as a stroke volume index ≤35 mL/m(2), low gradient as a mean gradient ≤40 mm Hg. Most patients (n=258, 75.9%) presented with high-gradient AS, and 82 patients (24.1%) with low-gradient AS. Among the latter, 52 (15.3%) presented with normal flow and low gradient and 30 (8.8%) with LFLG. As compared with normal flow and low gradient, patients with LFLG had more severe AS (aortic valve area=0.7±0.12 cm(2) versus 0.86±0.14 cm(2)), higher valvulo-arterial impedance (5.5±1.1 versus 4±0.8 mm Hg/mL/m(2)), and worse longitudinal left ventricular function (basal longitudinal strain=-11.6±3.4 versus -14.8±3%; P<0.001 for all).
  
  
  CONCLUSIONS
  LFLG AS is observed in 9% of patients with severe AS and normal ejection fraction and is associated with high global afterload and reduced longitudinal systolic function. Patients with normal-flow low-gradient AS are more frequent and present with less severe AS, normal afterload, and less severe longitudinal dysfunction. Severe left ventricular longitudinal dysfunction is a new explanation to the concept of LFLG AS.
authors: Department of Cardiology, la Timone Hospital, Marseille, France.
authors: Jérôme
authors: J
authors: Adda
authors: Christopher
authors: C
authors: Mielot
authors: Roch
authors: R
authors: Giorgi
authors: Frédéric
authors: F
authors: Cransac
authors: Xavier
authors: X
authors: Zirphile
authors: Erwan
authors: E
authors: Donal
authors: Catherine
authors: C
authors: Sportouch-Dukhan
authors: Patricia
authors: P
authors: Réant
authors: Stéphane
authors: S
authors: Laffitte
authors: Stéphane
authors: S
authors: Cade
authors: Yvan
authors: Y
authors: Le Dolley
authors: Franck
authors: F
authors: Thuny
authors: Nathalie
authors: N
authors: Touboul
authors: Cécile
authors: C
authors: Lavoute
authors: Jean-François
authors: JF
authors: Avierinos
authors: Patrizio
authors: P
authors: Lancellotti
authors: Gilbert
authors: G
authors: Habib
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000150:complications* / Q000000981:diagnostic imaging*; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000150:complications* / Q000000981:diagnostic imaging*