title: The role of cardiopulmonary exercise test in mitral and aortic regurgitation: it can predict post-operative results.
abstract: BACKGROUND
  We evaluated the efficacy of the cardiopulmonary exercise test as an objective indicator of functional status and as a pre-operative prognostic indicator in patients with mitral regurgitation (MR) and aortic regurgitation (AR).
  
  
  METHODS
  Cardiopulmonary exercise tests and echocardiography were performed in 47 patients (MR: 30, AR: 15, MR + AR: 2) before surgery and repeated one year after surgery. We compared the New York Heart Association (NYHA) functional class, peak oxygen consumption rate (VO2peak), exercise duration, left ventricular dimension and ejection fraction, before and after surgery.
  
  
  RESULTS
  Initial VO2peak and exercise duration were significantly different according to NYHA class. A year later, NYHA functional class improved from 2.1 +/- 0.1 to 1.4 +/- 0.1 (p < 0.001). The VO2peak was significantly increased (21.7 +/- 1.0 to 23.7 +/- 1.0 mL/kg per min, p = 0.008) and exercise duration also increased (521.7 +/- 35.9 to 623.3 +/- 35.7 seconds, p < 0.001). When patients were analysed according to their post-operative NYHA functional class, those with class I showed significantly different pre-operative VO2peak (class I: 23.7 +/- 1.1, II: 18.3 +/- 1.5 mL/kg per min, p = 0.005) and exercise durations (class I: 587.5 +/- 43.2, II: 415.6 +/- 55.7 seconds, p = 0.02). Patients with higher pre-operative VO2peak (19.0 mL/kg per min) more frequently became NYHA functional class I than those with a lower pre-operative VO2peak (76.7% vs. 35.3%, p = 0.02). But baseline left ventricular dimension and ejection fraction by echocardiography were not different between post-operative class I and II group.
  
  
  CONCLUSIONS
  VO2peak and exercise duration are excellent parameters to evaluate the subjective functional class and to predict the post-operative functional class of patients with MR and/or AR. Patients with a pre-operative VO2peak of 19.0 mL/kg per min or more will have a better functional status one year after surgery.
authors.affiliation: Division of Cardiovascular Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-ku, Seoul 135-170, Korea. kphong@smc.samsung.co.kr
authors.forename: Hyun Joong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Byung Ryul
authors.initials: BR
authors.lastname: Cho
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Hong
authors.forename: Pyo Won
authors.initials: PW
authors.lastname: Park
authors.forename: Kyung Pyo
authors.initials: KP
authors.lastname: Hong
mesh_terms: D000328:Adult; D001022:Aortic Valve Insufficiency / Q000175:diagnosis / Q000601:surgery*; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000175:diagnosis / Q000601:surgery*; D010101:Oxygen Consumption; D011184:Postoperative Period; D011300:Preoperative Care; D011336:Probability; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013318:Stroke Volume; D016896:Treatment Outcome