Prognostic Value of Right Ventricular Ejection Fraction Assessed by Transthoracic 3D Echocardiography.
BACKGROUND
Cardiac magnetic resonance is the gold standard for the evaluation of right ventricular (RV) volumes, but it is impractical to perform in every patient. Although reference values of RV volumes and RV ejection fraction by 3D transthoracic echocardiography (3DTTE) have been established, their prognostic values have not been elucidated yet. We hypothesized that RV ejection fraction measured by 3DTTE (3DRVEF) predicts future cardiovascular events.


RESULTS
In protocol 1, we determined the accuracy of RV volumes and RV ejection fraction measurements by 3DTTE against cardiac magnetic resonance in 60 subjects. In protocol 2, 3DRVEF was measured in 446 patients with various cardiovascular diseases. Study subjects were followed up to record cardiac death and major adverse cardiovascular events. In protocol 1, 3DTTE-determined RV end-diastolic volume, end-systolic volume, and RV ejection fraction had good correlations to those by cardiac magnetic resonance (r=0.74-0.90). In protocol 2, 38 cardiac deaths and 88 major adverse cardiovascular events occurred during a median follow-up of 4.1 years. Univariable Cox proportional analysis revealed that 3DRVEF was associated with both cardiac death (P<0.0001) and major adverse cardiovascular event (P<0.0001). 3DRVEF remained as an independent predictor for cardiac death (P<0.0001) and major adverse cardiovascular event (P<0.0001) even in a stepwise multivariable Cox proportional hazard analysis. Classification and regression-tree analysis demonstrated that 3DRVEF played an important role for risk stratification.


CONCLUSIONS
3DTTE-determined RV ejection fraction was independently associated with cardiac outcomes in patients with diverse backgrounds. 3DRVEF offered incremental value over clinical risk factors and the other echocardiographic parameters including left ventricular systolic and diastolic function for predicting future adverse outcome.
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.). nyasufumi1979@yahoo.co.jp.
Yasufumi
Y
Nagata
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.).
Victor Chien-Chia
VC
Wu
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.).
Yuichiro
Y
Kado
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.).
Kyoko
K
Otani
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.).
Fen-Chiung
FC
Lin
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.).
Yutaka
Y
Otsuji
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.).
Kazuaki
K
Negishi
From the Second Department of Internal Medicine (Y.N., V.C.-C.W., Y.K., Y.O.) and Department of Laboratory and Transfusion Medicine (K.O., M.T.), School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taipei, Taiwan (V.C.-C.W., F.-C.L.); and Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (K.N.).
Masaaki
M
Takeuchi
D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D016009:Chi-Square Distribution; D019560:Echocardiography, Three-Dimensional; D005260:Female; D006331:Heart Diseases / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D006801:Humans; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right
echocardiography; prognosis; right ventricle; three-dimensional; ventricular function