title: Additive prognostic values of NT-proBNP and exercise stress echocardiography in asymptomatic patients with degenerative mitral regurgitation and preserved left ventricular ejection fraction.
abstract: BACKGROUND
  Exercise stress echocardiography (ESE) can be used to identify left ventricular (LV) dysfunction in asymptomatic chronic MR. NT-proBNP is the best marker for monitoring LV dysfunction.
  
  
  OBJECTIVE
  The aim of this study was to estimate the complementary prognostic value of ESE and NT-proBNP in asymptomatic degenerative MR with preserved LV ejection fraction (EF).
  
  
  METHODS
  Symptom-limited treadmill ESE was performed in 114 asymptomatic with significant degenerative MR (ERO >20mm, RV >30ml), LV end-systolic diameter <40mm and preserved LV function (EF >60%). Post-exercise EF increase of >4% was defined as contractile reserve (CR)+.
  
  
  RESULTS
  MV operation was performed in 19 (16.7%) and new-onset LV systolic dysfunction was developed in 23 (20.2%) patients over 3.5±1.5years. Based on ROC curve analysis, a NT-pro BNP of 100 was deemed the most relevant cutoff value to predict primary outcome with Youden's index=131.84. In sequential Cox models, a model based on clinical data and resting echocardiography variables (χ2=6.87) was improved by NT-proBNP (χ2=13.9) and presence of CR in ESE (χ2=20.8; p=0.0002).
  
  
  CONCLUSIONS
  In asymptomatic moderate to severe or severe degenerative MR and preserved LVEF, the presence of CR in ESE and NT-proBNP provide important incremental clinical determinants. In particular, the prognosis is markedly poor for those with high NT-proBNP but with absence of CR than low NT-proBNP with presence of CR.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardiovascular Imaging Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. Electronic address: tyche.park@gmail.com.
authors.forename: Sung-Ji
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Division of Cardiology, Department of Medicine, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Eun Jeong
authors.initials: EJ
authors.lastname: Cho
authors.affiliation: Biostatistics and Clinical Epidemiology Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea.
authors.forename: Joonghyun
authors.initials: J
authors.lastname: Ahn
authors.affiliation: Biostatistics and Clinical Epidemiology Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea; Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, AB, Canada.
authors.forename: Keumhee
authors.initials: K
authors.lastname: Carriere
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardiovascular Imaging Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Eun Kyoung
authors.initials: EK
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardiovascular Imaging Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Ga Yeon
authors.initials: GY
authors.lastname: Lee
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardiovascular Imaging Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Sung-A
authors.initials: SA
authors.lastname: Chang
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardiovascular Imaging Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Jin-Oh
authors.initials: JO
authors.lastname: Choi
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardiovascular Imaging Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Sang-Chol
authors.initials: SC
authors.lastname: Lee
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardiovascular Imaging Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D058070:Asymptomatic Diseases; D015415:Biomarkers / Q000097:blood; D025401:Echocardiography, Stress / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000097:blood* / Q000000981:diagnostic imaging* / Q000503:physiopathology; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011379:Prognosis; D011446:Prospective Studies; D013318:Stroke Volume / Q000502:physiology*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: Asymptomatic; Exercise echocardiography; Mitral regurgitation; NT-proBNP