Importance of Nonlongitudinal Motion Components in Right Ventricular Function: Three-Dimensional Echocardiographic Study in Healthy Volunteers

Abstract

Background: Global right ventricular (RV) function is determined by the interplay of different motion components related to the myofiber architecture, and the relative importance of these components is still not thoroughly characterized. The aims of this study were to quantify the relative contributions of longitudinal, radial, and anteroposterior motion components to global RV function and to examine their determining factors in a large cohort of healthy volunteers using three-dimensional echocardiography. Methods: Three hundred healthy adults with a balanced age range and an equal sex distribution were investigated at two centers. A three-dimensional mesh model of the right ventricle was generated, and its motion was decomposed along the three anatomically relevant axes. Multiplicative relative contributions were measured by dividing the ejection fraction (EF) values generated by shortening in the longitudinal, radial, and anteroposterior directions by global RV EF (longitudinal EF index [LEFi], radial EF index [REFi], and anteroposterior EF index, respectively). The circumferential contribution was defined as shortening in the radial and anteroposterior directions, omitting only longitudinal shortening. Results: Circumferential EF index was markedly higher compared with LEFi (79 6 7% vs 47 6 9%, P < .001). LEFi (47 6 9%) and anteroposterior EF index (49 6 7%) were found to be similar in the pooled population, whereas REFi (44 6 10%) was lower (P < .001). In younger individuals (20-39 years of age), the relative contribution of longitudinal shortening was significantly higher compared with the radial component; however, in the older age groups, LEFi and REFi were comparable. Age, body surface area, heart rate, and RV end-diastolic volume were independent predictors of LEFi and REFi, but all with opposite effects on the two motion directions. Conclusions: In contrast to the traditional viewpoint, the contributions of the radial and anteroposterior motion directions may be of comparable significance with that of longitudinal shortening in determining global RV function. Standard parameters referring only to longitudinal shortening of the right ventricle may be inadequate to characterize RV function thoroughly.

Partitioning the Right Ventricle Into 15 Segments and Decomposing Its Motion Using 3D Echocardiography-Based Models: The Updated ReVISION Method

“…For this purpose, we developed the Right VentrIcular Separate wall motIon quantificatiON (ReVISION) method a few years ago, which is a 3D echocardiography (3DE)-based solution for the quantification of the relative contribution of longitudinal, radial, and anteroposterior shortening to global RV EF (9). Since then, our technology has been applied in several clinical scenarios (10)(11)(12), and the strengths of the ReVISION method have been demonstrated in the in-depth characterization of RV mechanical pattern and the prognostication of patients even in the face of maintained RV EF (13). The ReVISION method and the associated online platform (demo version available at https://www.revisionmethod.com) are improved continuously, and recently, various new features, such as the assessment of longitudinal, circumferential, and area strains have been implemented to enable the convenient, standardized, and more comprehensive analysis of RV function using 3DE datasets.…”

High-intensity Interval Training Enhances Hypoxia-mediated Right Cardiac Mechanics in Sedentary Men

“…Although most studies have focused on longitudinal motion to generate RV ejection, our study further con rmed that RV dilation primarily occurred in the radial direction instead of the longitudinal direction. Elevated radial motion in uences systolic function via the bellows effect because the free wall of the right ventricle has a larger surface than the tricuspid annular cross-sectional area 23 . Therefore, we speculated that the improvement of ejection fraction during HE is related with not only longitudinal but also radial motion.…”

Comprehensive Echocardiographic Assessment of the Right Ventricular Performance: beyond TAPSE and Fractional Area Change

“…However, the implementation of 3DE enabled more granular understanding of RV shape and mechanics [22]. A recent study revealed that the inward motion of the free wall (radial shortening, the so-called "bellows effect") and interestingly, the anteroposterior shortening (mainly caused by the stretching of the RV free wall insertion points by the LV contraction) are of comparable significance to longitudinal shortening in healthy volunteers [23]. The bellows effect is justified by the circumferentially oriented myofibers which prevail at the subepicardial layer of the RV myocardium [22].…”