title: Development of paradoxical low-flow, low-gradient severe aortic stenosis.
abstract: OBJECTIVE
  Among patients with severe aortic stenosis (sAS) and preserved LVEF, those with low-flow, low-gradient sAS (LFLG-sAS) have an adverse prognosis. It has been proposed that LFLG-sAS represents an end-stage point of sAS, but longitudinal information has not been described. The aim was to determine whether LFLG-sAS represents an end-stage consequence of normal-flow, high-gradient sAS (NFHG-sAS) or a different entity.
  
  
  METHODS
  From our transthoracic echocardiogram (TTE) database, we identified patients with sAS (aortic valve area <1 cm(2)) and preserved LVEF (≥50%), and from these, patients with LFLG-sAS (stroke volume index <35 mL/m(2) and mean transvalvular gradient <40 mm Hg) who had ≥1 additional TTE within five years prior to the index TTE. Patients were age/sex/date matched 2:1 with patients with NFHG-sAS and normal-flow, low-gradient (NFLG)-sAS who also had ≥1 TTE. Included were 1203 TTEs (383 index studies and 820 preceding studies).
  
  
  RESULTS
  In 78 patients with LFLG-sAS, an HG stage preceded the index TTE in only 4 (5%). During the five years preceding the index TTE, patients with LFLG-sAS developed increasing relative wall thickness (0.42 to 0.49; p<0.001) without change in LV mass index. Patients with NFHG-sAS had a marked increase in LV mass index (87 to 115 g/m(2); p<0.001). Patients with LFLG-sAS demonstrated the greatest reduction in LV end-diastolic diameters (-3 vs -1 for NFLG-sAS vs +2 mm for NFHG-sAS; p=0.001), deceleration time (-55 vs -3 vs +3 ms, respectively; p<0.01) and LVEF (-4 vs 0 vs 0%, respectively; p=0.01).
  
  
  CONCLUSIONS
  LFLG-sAS is a distinct presentation of sAS preceded by a unique remodelling pathway and is uncommonly preceded by an HG stage.
authors: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
authors: Jordi S
authors: JS
authors: Dahl
authors: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
authors: Mackram F
authors: MF
authors: Eleid
authors: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
authors: Sorin V
authors: SV
authors: Pislaru
authors: Division of Biostatistics Mayo Clinic, Rochester, Minnesota, USA.
authors: Christopher G
authors: http://orcid.org/0000-0003-1340-0647
authors: CG
authors: Scott
authors: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
authors: Heidi M
authors: HM
authors: Connolly
authors: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
authors: Patricia A
authors: PA
authors: Pellikka
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000175:diagnosis / Q000503:physiopathology; D018450:Disease Progression; D004452:Echocardiography / Q000379:methods; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006439:Hemodynamics; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology*; D014481:United States; D016277:Ventricular Function, Left / Q000502:physiology*