title: Contractile reserve determined on exercise echocardiography in patients with severe aortic regurgitation.
abstract: BACKGROUND
  The aim of this study was to assess contractile reserve (CR) in patients with severe aortic regurgitation (AR), and potential clinical applications of CR in minimally symptomatic patients.
  
  
  RESULTS
  Symptom-limited treadmill exercise echocardiography was performed in 58 asymptomatic or mildly symptomatic patients with chronic severe AR (male 69%, 50±14 years). Patients with increased ejection fraction (EF) after exercise were denoted as having CR (+) and those without increased EF were categorized as CR (-). CR (+) was found in 31 and CR (-) in 27 patients. Compared with CR (+), the CR (-) group had lower EF, larger effective regurgitant orifice, regurgitant volume, left ventricular (LV) end-diastolic dimension, LV end-systolic dimension (LVESD), and LV mass index. On multiple logistic regression analysis LVESD index (LVESDI; odds ratio -0.354, P<0.0001) was an independent predictor of CR. One-third of patients with LVESD >50mm, however, were found to be CR (+), while one-third of patients with smaller LVESD were CR (-).
  
  
  CONCLUSIONS
  Although CR is best related to baseline resting LVESDI, one-third of patients were found to have discordance between the presence of CR and the LV dimension recommended for aortic valve replacement (AVR) in minimally symptomatic patients with severe AR, suggesting that exercise test may be able to further stratify the current guideline for AVR.
authors.affiliation: Cardiovascular Imaging Center, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Sung-Ji
authors.initials: SJ
authors.lastname: Park
authors.forename: Maurice
authors.initials: M
authors.lastname: Enriquez-Sarano
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Song
authors.forename: Yung-Joo
authors.initials: YJ
authors.lastname: Lee
authors.forename: Mi-Ran
authors.initials: MR
authors.lastname: Ha
authors.forename: Sung-A
authors.initials: SA
authors.lastname: Chang
authors.forename: Jin-Oh
authors.initials: JO
authors.lastname: Choi
authors.forename: Sang-Chol
authors.initials: SC
authors.lastname: Lee
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Jae K
authors.initials: JK
authors.lastname: Oh
mesh_terms: D000328:Adult; D000368:Aged; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D025401:Echocardiography, Stress; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D012189:Retrospective Studies; D012720:Severity of Illness Index