Recent Echocardiographic Advance in Right Ventricular Functional Assessment

Recent advance in echocardiographic right ventricular (RV) functional assessment has following three major issues; first RV longitudinal strain, second RV ejection fraction by three-dimensional echocardiography, third RV dyssynchrony. RV longitudinal systolic function is conventionally assessed by the M-mode echocardiography and tricuspid annular plane systolic excursion (TAPSE) is obtained. Longitudinal shortening of RV reflects the intrinsic endocardial right myocardial fiber contraction, however, TAPSE dependent not only the RV deformation but also reflecting the tethering from left ventricular apical movement. Speckle tracking echocardiography can apply to the RV free wall, and provide accurate right ventricular systolic shortening fraction independently from the left ventricular tethering. Three-dimensional (3D) echocardiography development has progressed, several volumetric assessment tools were clinically available. Recently, both transthoracic and transesophageal 3D dataset can be processed and accuracy of these method improving dramatically and now comparable with the cardiac magnetic resonance imaging. RV dyssynchrony derived from two- or three-dimensional speckle tracking echocardiography has been focused by the several investigators. Dyssynchronous contraction has been reported to be the early and important mechanism reflecting interventricular interaction or electrical conduction delay and resulting in dyscoordinated cardiac contraction. Because RV temporal contraction pattern has not been fully investigated in various clinical conditions, the further study must be emerging in this field.