Diastolic right ventricular filling vortex in normal and volume overload states

Abstract

Functional imaging computational fluid dynamics simulations of right ventricular (RV) inflow fields were obtained by comprehensive software using individual animal-specific dynamic imaging data input from three-dimensional (3-D) real-time echocardiography (RT3D) on a CRAY T-90 supercomputer. Chronically instrumented, lightly sedated awake dogs (n = 7) with normal wall motion (NWM) at control and normal or diastolic paradoxical septal motion (PSM) during RV volume overload were investigated. Up to the E-wave peak, instantaneous inflow streamlines extended from the tricuspid orifice to the RV endocardial surface in an expanding fanlike pattern. During the descending limb of the E-wave, large-scale (macroscopic or global) vortical motions ensued within the filling RV chamber. Both at control and during RV volume overload (with or without PSM), blood streams rolled up from regions near the walls toward the base. The extent and strength of the ring vortex surrounding the main stream were reduced with chamber dilatation. A hypothesis is proposed for a facilitatory role of the diastolic vortex for ventricular filling. The filling vortex supports filling by shunting inflow kinetic energy, which would otherwise contribute to an inflow-impeding convective pressure rise between inflow orifice and the large endocardial surface of the expanding chamber, into the rotational kinetic energy of the vortical motion that is destined to be dissipated as heat. The basic information presented should improve application and interpretation of noninvasive (Doppler color flow mapping, velocity-encoded cine magnetic resonance imaging, etc.) diastolic diagnostic studies and lead to improved understanding and recognition of subtle, flow-associated abnormalities in ventricular dilatation and remodeling.

4-D blood flow in the human right ventricle

“…In a large animal study, a presystolic increase in LV outflow tract volume has been suggested to prepare the aortic valve for ejection (22). Furthermore, preservation of the inflow KE may also facilitate the filling process by a smaller inflowimpeding pressure rise between inflow orifice and the endocardial surface of the expanding RV chamber (20). Although the Direct Flow was larger in the RV compared with the LV, the total end-diastolic KE of the Direct Flow was not larger on the right side.…”

Assessment of right ventricular diastolic suction in dogs with the use of wave intensity analysis

“…Tricuspid velocity was measured near the midpoint of the tricuspid annulus using Doppler echocardiography. This velocity should be representative of the entire cross section in that the velocity profile is blunt in early diastole (26,27). The two variables studied, Ј and V RVES , are not ideally independent.…”

Complementarity and competitiveness of the intrinsic and extrinsic components of the total ventricular load: Demonstration after valve replacement in aortic stenosis

“…3,[13][14][15][16] Larger intraventricular gradients can be demonstrated when blood is ejected rapidly from an enlarged chamber through a normal-sized aortic anulus 3,4 as in aortic regurgitation, an instance of systolic ventriculoannular disproportion. 3 Analogous concepts were more recently put forward, [17][18][19] that govern previously unrecognized important aspects of the diastolic ventricular filling load. A new mechanism, the convective deceleration load, 18,19 was formulated as an important determinant of diastolic inflow during the upstroke of the E wave.…”

“…3 Analogous concepts were more recently put forward, [17][18][19] that govern previously unrecognized important aspects of the diastolic ventricular filling load. A new mechanism, the convective deceleration load, 18,19 was formulated as an important determinant of diastolic inflow during the upstroke of the E wave. The larger the chamber, the larger becomes the convective deceleration load.…”

“…This underlies the concept of a diastolic ventriculoannular disproportion. [17][18][19] In the presence of left (right) ventricular outflow tract obstruction, including aortic (pulmonic) valvular stenosis, intraventricular ejection gradients of large magnitude are typical. 2,3,20 The total systolic ejection load Through the above-mentioned endeavors, the view was developed 3,13 that total ventricular systolic load comprises both extrinsic (the aortic root ejection pressure waveform) and intrinsic (flow-associated intraventricular pressure gradients) components.…”