scholarly journals Vortex formation time: an emerging echocardiographic index of left ventricular filling efficiency?

2012 ◽  
Vol 13 (5) ◽  
pp. 367-369 ◽  
Author(s):  
M. Belohlavek



2019 ◽  
Vol 35 (2) ◽  
pp. 307-311 ◽  
Author(s):  
Gerard King ◽  
Nicholas Ngiam ◽  
John Clarke ◽  
Malissa J. Wood ◽  
Kian-Keong Poh




Heart Asia ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. e011188 ◽  
Author(s):  
Kian Keong Poh ◽  
Nicholas Ngiam ◽  
Malissa J Wood

BackgroundEfficient transportation of blood through the left ventricle (LV) during diastole depends on vortex formation. Vortex formation time (VFT) can be measured by echocardiography as a dimensionless index. As elite athletes have supranormal diastolic LV function, we aim to assess resting and post-exercise VFT in these athletes and hypothesised that VFT may predict myocardial performance immediately post-exercise.MethodSubjects were world class speedskaters training for the Winter Olympic Games. Echocardiographic measurements were obtained before and immediately after 3000 m of racing. VFT was computed as 4×(1−β)/π×α³×left ventricle ejection fraction where β is the fraction of diastolic stroke volume contributed by atrial contraction, α is the biplane end diastolic volume (EDV)1/3 divided by mitral annular diameter during early diastole.ResultsBaseline VFT was 2.6±0.7 (n=24, age 22±3 years, 67% males). Post-exercise, heart rates increased (64±10 vs 89±12 beats/min, p<0.01); however, VFT was unchanged (2.9±1.0, p>0.05). VFT at rest correlated modestly with post-exertion early diastolic mitral in-flow velocity (E; r=0.59, p=0.01), tissue Doppler-derived early mitral annular velocity (E′; septal and lateral, both r=0.59, p=0.01) and systolic annular velocity (S′; septal: r=0.46, p=0.02 and lateral: r=0.48, p=0.02) but not late diastolic mitral in-flow velocity (A; r=0.06, p>0.05) or annular velocity (A′; septal: r=0.34, p=NS and lateral: r=0.35, p>0.05).ConclusionThere was no significant difference between VFT at rest and immediately post-exercise. However, VFT at rest correlated with immediate post-exercise augmented systolic and early diastolic tissue Doppler indicators of myocardial performance in elite athletes.



2010 ◽  
Vol 109 (6) ◽  
pp. 1812-1819 ◽  
Author(s):  
Erina Ghosh ◽  
Leonid Shmuylovich ◽  
Sándor J. Kovács

During early rapid filling, blood aspirated by the left ventricle (LV) generates an asymmetric toroidal vortex whose development has been quantified using vortex formation time (VFT), a dimensionless index defined by the length-to-diameter ratio of the aspirated (equivalent cylindrical) fluid column. Since LV wall motion generates the atrioventricular pressure gradient resulting in the early transmitral flow (Doppler E-wave) and associated vortex formation, we hypothesized that the causal relation between VFT and diastolic function (DF), parametrized by stiffness, relaxation, and load, can be elucidated via kinematic modeling. Gharib et al. (Gharib M, Rambod E, Kheradvar A, Sahn DJ, Dabiri JO. Proc Natl Acad Sci USA 103: 6305–6308, 2006) approximated E-wave shape as a triangle and calculated VFTGharib as triangle (E-wave) area (cm) divided by peak (Doppler M-mode derived) mitral orifice diameter (cm). We used a validated kinematic model of filling for the E-wave as a function of time, parametrized by stiffness, viscoelasticity, and load. To calculate VFTkinematic, we computed the curvilinear E-wave area (using the kinematic model) and divided it by peak effective orifice diameter. The derived VFT-to-LV early rapid filling relation predicts VFT to be a function of peak E-wave-to-peak mitral annular tissue velocity (Doppler E′-wave) ratio as (E/E′)3/2. Validation utilized 262 cardiac cycles of simultaneous echocardiographic high-fidelity hemodynamic data from 12 subjects. VFTGharib and VFTkinematic were calculated for each subject and were well-correlated ( R2 = 0.66). In accordance with prediction, VFTkinematic to (E/E′)3/2 relationship was validated ( R 2 = 0.63). We conclude that VFTkinematic is a DF index computable in terms of global kinematic filling parameters of stiffness, viscoelasticity, and load. Validation of the fluid mechanics-to-chamber kinematics relation unites previously unassociated DF assessment methods and elucidates the mechanistic basis of the strong correlation between VFT and (E/E′)3/2.



2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
Y Dimitroglou ◽  
C Aggeli ◽  
D Maragiannis ◽  
D Patsourakos ◽  
I Gountas ◽  
...  

Abstract Background Vortex Formation Time (VFT) is a novel index of systolic and diastolic function which may be also affected by left ventricular geometry, but has never been evaluated during dobutamine stress echocardiography (DSE) protocols. We sought to investigate the changes in VFT during DSE protocol. Methods DSE was performed in 50 consecutive patients. Patients with poor acoustic window, atrial fibrillation, cardiac valve disease or pacemaker were excluded. Apical four and apical two chamber views were acquired and the following parameters were calculated off- line without knowledge of DSE result both at rest and at peak: left ventricular end-diastolic and end-systolic volume, stroke volume, ejection fraction, stroke work, e and a wave peak velocity and VTI, TDI-derived mitral annular early diastolic velocity at the lateral wall and mitral valve diameter. VFT calculated according to the following equation: VFT = [4 *(1 − β) * α3 * EF]/π, where α = (LVEDV/α3)(1/3) and is affected by ventricular geometry and β = VTIa-wave/(VTIe wave + VTIa-wave) reflecting the atrial filling fraction. Results Median age of the study population was 61 [53–72], 38 men (76%) and 13 (26%) had an old myocardial infarction. Fifteen patients (30%) were positive for myocardial ischemia during DSE. At rest, median LVEDV was 121.5ml (101.8–148.0), median EF (%): 59.9 [54.4–64.1], median atrial filling fraction: 0.43 [0.40–0.48], median mitral valve diameter (cm): 2.8 [2.6–3.0] and median VFT: 2.44 [1.74–3.10]. At peak, median LVEDV was 102.0ml [86.4–122.3] median EF (%) 65.7 [58.8–69.8], median atrial filling fraction: 0.67 [0.59–0.73], median mitral valve diameter (cm): 2.7 [2.5–2.9] and median VFT: 1.45 [1.05–1.88]. VFT decreased in the whole population (Wilcoxon rank test, p<0.001) (figure 1A) and when patients were stratified according to test result. Median VFT decrease was significantly higher in patients with a positive DSE (50%) than in patients with negative DSE (39%) (Mann- Whitney U test, p=0.048) (figure 1B). Figure 1 Conclusion The VFT decreased significantly during DSE and most prominently in patients with ischemic response. This may indicate the deterioration of left ventricular diastolic or systolic function as well as change in left ventricular geometry during DSE protocol.





1999 ◽  
Vol 1 ◽  
pp. S35-S35
Author(s):  
S RTSKHILADZE ◽  
R NAPETVARIDZE ◽  
N EMUKHVARI ◽  
S PETRIASHVILI ◽  
I KHINTIBIDZE ◽  
...  


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