title: Impact of prolapsing leaflet location on exercise pulmonary hypertension in mitral regurgitation.
abstract: OBJECTIVE
  We aimed to evaluate whether prolapsing leaflet-specific exercise pulmonary hypertension (PHT) exists and to identify the related mechanisms.
  
  
  RESULTS
  Resting and bicycle exercise transthoracic echocardiography was performed in 35 consecutive patients (aged 56 ± 11, 69% men) with asymptomatic, moderate-to-severe, and degenerative mitral regurgitation (MR). The patients were classified into two groups according to the prolapsing leaflet: an anterior mitral leaflet (AML) group (n = 17) and a posterior mitral leaflet (PML) group (n = 18). At rest, the MR severity and systolic pulmonary artery pressure (SPAP) were similar between the two groups. During exercise, changes in the regurgitant volume (ΔRV) were markedly increased in the PML group compared with the AML group (23.9 ± 13.6 vs. 13.9 ± 10.5 mL, P= 0.022). Moreover, exercise-induced changes in SPAP (ΔSPAP) were more significant in the PML group (35.8 ± 10.7 vs. 26.7 ± 8.7 mmHg, P= 0.009). Further analysis of the resting left atrial (LA) characteristics revealed decreased LA reservoir function and a more ellipsoid left atrium in the PML group. Multiple linear regression analysis revealed that ΔRV was an independent determinant of ΔSPAP (β= 0.34, P= 0.013) after adjustment for other confounding factors.
  
  
  CONCLUSIONS
  PML prolapse is associated with a greater increase in exercise-induced SPAP, and the prominent increase in MR severity in PML prolapse is thought to be the main mechanism responsible for this increase. The current study suggests the need for more frequent follow-up of patients with PML prolapse.
authors.affiliation: Cardiovascular Center, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul 137-701, Republic of Korea.
authors.forename: Mi-Hyang
authors.initials: MH
authors.lastname: Jung
authors.affiliation: Cardiovascular Center, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul 137-701, Republic of Korea.
authors.forename: Hae Ok
authors.initials: HO
authors.lastname: Jung
authors.affiliation: Department of Cardiology, College of Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Republic of Korea.
authors.forename: Mi-Jeong
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Cardiovascular Center, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul 137-701, Republic of Korea.
authors.forename: Jung-Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Cardiovascular Center, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul 137-701, Republic of Korea.
authors.forename: Ho-Joong
authors.initials: HJ
authors.lastname: Youn
mesh_terms: D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D004452:Echocardiography / Q000379:methods; D025401:Echocardiography, Stress / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology / Q000503:physiopathology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008945:Mitral Valve Prolapse / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015999:Multivariate Analysis; D011379:Prognosis; D012146:Rest; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors
keywords: atrial function; exercise test; mitral valve insufficiency; mitral valve prolapse; pulmonary hypertension