title: Left atrial function assessed by real-time 3-dimensional echocardiography is related to right ventricular systolic pressure in chronic mitral regurgitation.
abstract: BACKGROUND
  Left atrial (LA) volume is a prognostic index in chronic mitral regurgitation (MR). However, little is known about LA function in this setting. We hypothesized that LA dysfunction is related to pulmonary hypertension in chronic MR.
  
  
  METHODS
  Seventy-one patients with organic chronic MR who underwent real-time 3-dimensional transthoracic echocardiography (RT3DE) were studied. Left atrial volumes and peak passive and active LA emptying rates were obtained. Total LA emptying fraction was calculated as follows: [(maximum - minimum LA volume)/maximum LA volume] x 100. Similarly, active and passive LA emptying fractions were calculated. From transmitral flow, the peak early (E) and late (A) diastolic filling velocities and E/A ratio were obtained. The early (E') and late (A') diastolic myocardial velocities were obtained by tissue Doppler interrogation of mitral annulus.
  
  
  RESULTS
  Effective regurgitant orifice area (EROA) was 0.57 +/- 0.29 cm(2). Right ventricular systolic pressure (RVSP) was measured in 57 patients and averaged 37 +/- 13 mm Hg. Patients with MR and high RVSP displayed higher minimum LA volume, E/A ratio, E/E' ratio, EROA, and MR volume, and lower A' velocity, peak active LA emptying rate, active LA emptying fraction, and total LA emptying fraction than patients with MR and normal RVSP. Multiple regression analysis revealed that EROA (r = 0.51, P = .01) active LA emptying fraction (r = -0.53, P = .02), E/E' ratio (r = 0.50; P = .04), and the lateral A' velocity (r = -0.46; P = .003) were independently correlated with RVSP.
  
  
  CONCLUSIONS
  Left atrial function determined by RT3DE had significant correlation with RVSP in chronic MR, irrespective of MR severity. Thus, pulmonary hypertension in chronic MR may depend not only on MR severity but also on LA function.
authors.affiliation: Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Roberto M
authors.initials: RM
authors.lastname: Saraiva
authors.forename: Tetsuhiro
authors.initials: T
authors.lastname: Yamano
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Matsumura
authors.forename: Kunitsugu
authors.initials: K
authors.lastname: Takasaki
authors.forename: Manatomo
authors.initials: M
authors.lastname: Toyono
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Agler
authors.forename: Neil
authors.initials: N
authors.lastname: Greenberg
authors.forename: James D
authors.initials: JD
authors.lastname: Thomas
authors.forename: Takahiro
authors.initials: T
authors.lastname: Shiota
mesh_terms: D000368:Aged; D016280:Atrial Function, Right / Q000502:physiology*; D002908:Chronic Disease; D003199:Computer Systems; D019560:Echocardiography, Three-Dimensional; D006801:Humans; D006976:Hypertension, Pulmonary / Q000453:epidemiology; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000503:physiopathology*; D011379:Prognosis; D012044:Regression Analysis; D012189:Retrospective Studies; D013599:Systole / Q000502:physiology; D017725:Ventricular Pressure