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Particle depositions and related hemodynamic parameters in the multiple stenosed right coronary artery.

Bernad SI, Bernad ES, Craina M, Sargan I, Totoran A, Brisan C - J Clin Med Res (2012)

Bottom Line: Energy loss associated with such flow expansion after each constriction will be large and consequently the pressure drop will be higher.Overall pressure drop increased from 1700 Pa (12.75 mmHg) at the end diastole to 11000 Pa (82.5 mmHg) at the peak systole.However at the end of one cardiac cycle a percent of 1.4% (15 from 1063 particles release at the inlet section) remain inside the stenosed RCA.

View Article: PubMed Central - PubMed

Affiliation: Centre for Fundamental and Advanced Research, Romanian Academy - Timisoara Branch, Timisoara, Romania.

ABSTRACT

Background: Blood flow analysis of the human right coronary artery (RCA) has been carried out to investigate the effects of serial stenosis on coronary hemodynamics. A 3-D model of a serial stenosed RCA was reconstructed based on multislice computerized tomography images.

Methods: A velocity waveform in the proximal RCA and a pressure waveform in the distal RCA of a patient with a severe stenosis were acquired with a catheter delivered wire probe and applied as boundary conditions. The numerical analysis examines closely the effect of a multiple serial stenosis on the hemodynamic characteristics such as flow separation, wall shear stress (WSS) and particle depositions.

Results and conclusions: Energy loss associated with such flow expansion after each constriction will be large and consequently the pressure drop will be higher. Overall pressure drop increased from 1700 Pa (12.75 mmHg) at the end diastole to 11000 Pa (82.5 mmHg) at the peak systole. At the peak systole the WSS values reached 110 Pa in the stenosis with 28% diameter reduction and 210 Pa in the stenosis with 54% diameter reduction, which is high enough to damage the endothelial cells. However at the end of one cardiac cycle a percent of 1.4% (15 from 1063 particles release at the inlet section) remain inside the stenosed RCA.

No MeSH data available.


Related in: MedlinePlus

Particle distribution inside to the stenosed RCA during the cardiac cycle. Instantaneous plot of the particle distributions for different time steps in downstream sections of the stenosis ST1, ST2 and ST3. At the end of the cardiac cycle a number of 15 particles (1063 seeded initially at the time T = 0 s) remain inside of the RCA. A number of 7 particles remain in vortical flow patterns result in downstream section of the more sever stenosis ST3.
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Figure 10: Particle distribution inside to the stenosed RCA during the cardiac cycle. Instantaneous plot of the particle distributions for different time steps in downstream sections of the stenosis ST1, ST2 and ST3. At the end of the cardiac cycle a number of 15 particles (1063 seeded initially at the time T = 0 s) remain inside of the RCA. A number of 7 particles remain in vortical flow patterns result in downstream section of the more sever stenosis ST3.

Mentions: Due to the severe occlusion and the relatively high Womersley number, platelet-rich zones enter the core of the flow where they are likely to be mixed with thrombin activated by the high shear stresses in the throat. Figures 9 and 10 show a decrease in particles count at the throat and increases in the proximal and distal regions of the serial stenosis. That is in correlation with the conclusions of the other groups [32, 33].


Particle depositions and related hemodynamic parameters in the multiple stenosed right coronary artery.

Bernad SI, Bernad ES, Craina M, Sargan I, Totoran A, Brisan C - J Clin Med Res (2012)

Particle distribution inside to the stenosed RCA during the cardiac cycle. Instantaneous plot of the particle distributions for different time steps in downstream sections of the stenosis ST1, ST2 and ST3. At the end of the cardiac cycle a number of 15 particles (1063 seeded initially at the time T = 0 s) remain inside of the RCA. A number of 7 particles remain in vortical flow patterns result in downstream section of the more sever stenosis ST3.
© Copyright Policy - open access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3376876&req=5

Figure 10: Particle distribution inside to the stenosed RCA during the cardiac cycle. Instantaneous plot of the particle distributions for different time steps in downstream sections of the stenosis ST1, ST2 and ST3. At the end of the cardiac cycle a number of 15 particles (1063 seeded initially at the time T = 0 s) remain inside of the RCA. A number of 7 particles remain in vortical flow patterns result in downstream section of the more sever stenosis ST3.
Mentions: Due to the severe occlusion and the relatively high Womersley number, platelet-rich zones enter the core of the flow where they are likely to be mixed with thrombin activated by the high shear stresses in the throat. Figures 9 and 10 show a decrease in particles count at the throat and increases in the proximal and distal regions of the serial stenosis. That is in correlation with the conclusions of the other groups [32, 33].

Bottom Line: Energy loss associated with such flow expansion after each constriction will be large and consequently the pressure drop will be higher.Overall pressure drop increased from 1700 Pa (12.75 mmHg) at the end diastole to 11000 Pa (82.5 mmHg) at the peak systole.However at the end of one cardiac cycle a percent of 1.4% (15 from 1063 particles release at the inlet section) remain inside the stenosed RCA.

View Article: PubMed Central - PubMed

Affiliation: Centre for Fundamental and Advanced Research, Romanian Academy - Timisoara Branch, Timisoara, Romania.

ABSTRACT

Background: Blood flow analysis of the human right coronary artery (RCA) has been carried out to investigate the effects of serial stenosis on coronary hemodynamics. A 3-D model of a serial stenosed RCA was reconstructed based on multislice computerized tomography images.

Methods: A velocity waveform in the proximal RCA and a pressure waveform in the distal RCA of a patient with a severe stenosis were acquired with a catheter delivered wire probe and applied as boundary conditions. The numerical analysis examines closely the effect of a multiple serial stenosis on the hemodynamic characteristics such as flow separation, wall shear stress (WSS) and particle depositions.

Results and conclusions: Energy loss associated with such flow expansion after each constriction will be large and consequently the pressure drop will be higher. Overall pressure drop increased from 1700 Pa (12.75 mmHg) at the end diastole to 11000 Pa (82.5 mmHg) at the peak systole. At the peak systole the WSS values reached 110 Pa in the stenosis with 28% diameter reduction and 210 Pa in the stenosis with 54% diameter reduction, which is high enough to damage the endothelial cells. However at the end of one cardiac cycle a percent of 1.4% (15 from 1063 particles release at the inlet section) remain inside the stenosed RCA.

No MeSH data available.


Related in: MedlinePlus