title: Usefulness of preoperative exercise tolerance to predict late survival and symptom persistence after surgery for chronic nonischemic mitral regurgitation.
abstract: Exercise duration during exercise treadmill testing (ETT) predicts long-term outcome among asymptomatic patients with mitral regurgitation. However, the prognostic value of preoperative exercise duration in patients who undergo mitral valve surgery is unknown. We examined findings among 45 prospectively followed (average 9.2 ± 4.3 years) patients (aged 54.8 ± 12.0 years, 45% men) with chronic isolated severe MR who underwent ETT before mitral valve surgery to test the hypotheses that exercise duration predicts long-term postoperative survival and persistent symptoms within 2 years after operation. During follow-up, 11 patients died; of these, 8 had persistent symptoms. Among patients who exercised >7 minutes, average annual postoperative all-cause and cardiovascular mortality risks were 0.75% (both endpoints) versus 5.4% and 4.8%, respectively, versus those who exercised ≤7 minutes (p = 0.003 all-cause, p = 0.007 cardiovascular). Exercise duration predicted postoperative deaths (p <.02 all cause, p <.04 cardiovascular) even when analysis was adjusted for preoperative variations in age, gender, medications, history of atrial fibrillation, and peak exercise heart rates. Other ETT, echocardiographic, and clinical variables were not independently associated with these outcomes when exercise duration was considered in the analysis. Preoperative exercise duration also predicted postoperative (New York Heart Association functional class ≥II) symptom persistence (p = 0.012), whereas other ETT, echocardiographic and clinical variables did not (NS, all). In conclusion, among patients who undergo surgery for chronic nonischemic mitral regurgitation, preoperative exercise duration, unlike many commonly used descriptors, is useful for predicting postoperative mortality and symptom persistence. Future research should determine whether interventions to improve exercise tolerance before mitral valve surgery can modify these postoperative outcomes.
authors.affiliation: The Howard Gilman Institute for Valvular Heart Diseases, State University of New York Downstate Medical Center, Brooklyn, NY, USA. phyllis.supino@downstate.edu
authors.forename: Phyllis G
authors.initials: PG
authors.lastname: Supino
authors.forename: Ofek Y
authors.initials: OY
authors.lastname: Hai
authors.forename: Tajinderpal S
authors.initials: TS
authors.lastname: Saraon
authors.forename: Edmund M
authors.initials: EM
authors.lastname: Herrold
authors.forename: Monica
authors.initials: M
authors.lastname: Diaz
authors.forename: Nasimullah
authors.initials: N
authors.lastname: Khan
authors.forename: Clare A
authors.initials: CA
authors.lastname: Hochreiter
authors.forename: Paul D
authors.initials: PD
authors.lastname: Kligfield
authors.forename: Karl H
authors.initials: KH
authors.lastname: Krieger
authors.forename: Leonard N
authors.initials: LN
authors.lastname: Girardi
authors.forename: O Wayne
authors.initials: OW
authors.lastname: Isom
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Borer
mesh_terms: D002908:Chronic Disease; D004452:Echocardiography; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000401:mortality* / Q000601:surgery; D009518:New York / Q000453:epidemiology; D057234:Preoperative Period; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D016896:Treatment Outcome