Vortex Ring Formation in the Left Ventricle of the Heart: Analysis by 4D Flow MRI and Lagrangian Coherent Structures

Abstract

Recent studies suggest that vortex ring formation during left ventricular (LV) rapid filling is an optimized mechanism for blood transport, and that the volume of the vortex ring is an important measure. However, due to lack of quantitative methods, the volume of the vortex ring has not previously been studied. Lagrangian Coherent Structures (LCS) is a new flow analysis method, which enables in vivo quantification of vortex ring volume. Therefore, we aimed to investigate if vortex ring volume in the human LV can be reliably quantified using LCS and magnetic resonance velocity mapping (4D PC-MR). Flow velocities were measured using 4D PC-MR in nine healthy volunteers and four patients with dilated ischemic cardiomyopathy. LV LCS were computed from flow velocities and manually delineated in all subjects. Vortex volume in the healthy volunteers was 51 ± 6% of the left ventricular volume, and 21 ± 5% in the patients. Interobserver variability was -1 ± 13% and interstudy variability was -2 ± 12%. Compared to idealized flow experiments, the vortex rings showed additional complexity and asymmetry, related to endocardial trabeculation and papillary muscles. In conclusion, LCS and 4D PC-MR enables measurement of vortex ring volume during rapid filling of the LV.

Left Ventricular Fluid Mechanics: The Long Way from Theoretical Models to Clinical Applications

“…62 A ''blood transit curve'' was introduced there, whose time profile shows the course of LV blood washout beat after beat, and whose first value corresponds to V direct . Assessment of LV stagnation regions in vivo was also performed on trajectory-based computation of Lagrangian coherent structures from CMR data, 93 and on velocity fields reconstructed by the colorDoppler approach. 40 It was demonstrated how these methods are capable of revealing the underlying topological structure of blood mixing and providing qualitative and quantitative assessments of blood transport patterns.…”

Effect of Fluid Viscosity on Noise of Bileaflet Prosthetic Heart Valve

“…Clinical studies of blood flow in the atria and ventricles are limited to the spatial and temporal resolution of non-invasive instruments such as echoDoppler cardiography and magnetic resonance imaging [7][8][9]. Currently, the most common method for diagnosing heart valves is the echo-Doppler cardiography.…”

Doppler vortography - Detection and quantification of the vortices in the left ventricle

“…In addition, vortex patterns can be missed in four-and two-chamber views in some subjects [92]. A detailed comparison of 3D and 2D cine PCMRI performed in vivo reveals that the 3D cine PCMRI provides slightly lower velocities [140].…”

“…However, because of the cost and complexity of this technique, a comprehensive clinical characterization of intra-ventricular flow dynamics in 67 different levels of cardiac disease has not yet been performed. PCMRI is combined with ECG and respiratory gating to obtain better quality images with higher spatial and temporal resolutions for full intra-cardiac flow mapping in several heart beats [24,25,49,65,[92][93][94]. In addition, the acquisition time using PCMRI is dependent on different parameters: size and location of the interested region, the spatial and temporal resolution and respiration pattern [24].…”