Limits...
Compensatory Effect between Aortic Stiffening and Remodelling during Ageing.

Guala A, Camporeale C, Ridolfi L - PLoS ONE (2015)

Bottom Line: These two degenerative processes however, have different impacts on the arterial wave pattern.They both tend to compensate for each other, thus reducing the detrimental effect they would have had if they had arisen individually.This remarkable compensatory mechanism is investigated by a validated multi-scale model, with the aim to elucidate how aortic stiffening and remodelling quantitatively impact the complex interplay between forward and reflected backward waves in the arterial network.

View Article: PubMed Central - PubMed

Affiliation: DIATI, Politecnico di Torino, Torino, Italy.

ABSTRACT
The arterial tree exhibits a complex spatio-temporal wave pattern, whose healthy behaviour depends on a subtle balance between mechanical and geometrical properties. Several clinical studies demonstrated that such a balance progressively breaks down during ageing, when the aorta stiffens and remodels by increasing its diameter. These two degenerative processes however, have different impacts on the arterial wave pattern. They both tend to compensate for each other, thus reducing the detrimental effect they would have had if they had arisen individually. This remarkable compensatory mechanism is investigated by a validated multi-scale model, with the aim to elucidate how aortic stiffening and remodelling quantitatively impact the complex interplay between forward and reflected backward waves in the arterial network. We focus on the aorta and on the pressure at the ventricular-aortic interface, which epidemiological studies demonstrate to play a key role in cardiovascular diseases.

No MeSH data available.


Related in: MedlinePlus

(a,b) Ageing-induced changes of reflection coefficients at main aortic bifurcations as seen by forward (a) and backward (b) waves travelling along the aorta. From left: brachiocephalic, left carotid, left subclavian, intercostals, celiac, superior mesenteric, left and right renal, and inferior mesenteric bifurcations. Circles indicate reflection coefficient values from 20 to 80 years of age with 10 years step, the darker the younger. (c-f) Reflection coefficients at left renal (c) and iliac (d) bifurcations, and re-reflection coefficients at celiac (e) and superior mesenteric (f) bifurcations during normal ageing (solid line), without aortic stiffening (dashed line), and without remodelling (dotted line).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4591291&req=5

pone.0139211.g002: (a,b) Ageing-induced changes of reflection coefficients at main aortic bifurcations as seen by forward (a) and backward (b) waves travelling along the aorta. From left: brachiocephalic, left carotid, left subclavian, intercostals, celiac, superior mesenteric, left and right renal, and inferior mesenteric bifurcations. Circles indicate reflection coefficient values from 20 to 80 years of age with 10 years step, the darker the younger. (c-f) Reflection coefficients at left renal (c) and iliac (d) bifurcations, and re-reflection coefficients at celiac (e) and superior mesenteric (f) bifurcations during normal ageing (solid line), without aortic stiffening (dashed line), and without remodelling (dotted line).

Mentions: Fig 2a and 2b shows the alterations of forward and backward reflection coefficients for the main aortic bifurcations. In young subjects, reflection coefficients for forward waves are generally close to zero, confirming that the aorta is well-matched for forward waves [36, 42]. During ageing, low values of Γ are substantially preserved in all locations, even though iliac bifurcation exhibits a sharp increment and subclavian and renal coefficients become positive. Again, these modelling findings are in agreement with clinical data [42].


Compensatory Effect between Aortic Stiffening and Remodelling during Ageing.

Guala A, Camporeale C, Ridolfi L - PLoS ONE (2015)

(a,b) Ageing-induced changes of reflection coefficients at main aortic bifurcations as seen by forward (a) and backward (b) waves travelling along the aorta. From left: brachiocephalic, left carotid, left subclavian, intercostals, celiac, superior mesenteric, left and right renal, and inferior mesenteric bifurcations. Circles indicate reflection coefficient values from 20 to 80 years of age with 10 years step, the darker the younger. (c-f) Reflection coefficients at left renal (c) and iliac (d) bifurcations, and re-reflection coefficients at celiac (e) and superior mesenteric (f) bifurcations during normal ageing (solid line), without aortic stiffening (dashed line), and without remodelling (dotted line).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4591291&req=5

pone.0139211.g002: (a,b) Ageing-induced changes of reflection coefficients at main aortic bifurcations as seen by forward (a) and backward (b) waves travelling along the aorta. From left: brachiocephalic, left carotid, left subclavian, intercostals, celiac, superior mesenteric, left and right renal, and inferior mesenteric bifurcations. Circles indicate reflection coefficient values from 20 to 80 years of age with 10 years step, the darker the younger. (c-f) Reflection coefficients at left renal (c) and iliac (d) bifurcations, and re-reflection coefficients at celiac (e) and superior mesenteric (f) bifurcations during normal ageing (solid line), without aortic stiffening (dashed line), and without remodelling (dotted line).
Mentions: Fig 2a and 2b shows the alterations of forward and backward reflection coefficients for the main aortic bifurcations. In young subjects, reflection coefficients for forward waves are generally close to zero, confirming that the aorta is well-matched for forward waves [36, 42]. During ageing, low values of Γ are substantially preserved in all locations, even though iliac bifurcation exhibits a sharp increment and subclavian and renal coefficients become positive. Again, these modelling findings are in agreement with clinical data [42].

Bottom Line: These two degenerative processes however, have different impacts on the arterial wave pattern.They both tend to compensate for each other, thus reducing the detrimental effect they would have had if they had arisen individually.This remarkable compensatory mechanism is investigated by a validated multi-scale model, with the aim to elucidate how aortic stiffening and remodelling quantitatively impact the complex interplay between forward and reflected backward waves in the arterial network.

View Article: PubMed Central - PubMed

Affiliation: DIATI, Politecnico di Torino, Torino, Italy.

ABSTRACT
The arterial tree exhibits a complex spatio-temporal wave pattern, whose healthy behaviour depends on a subtle balance between mechanical and geometrical properties. Several clinical studies demonstrated that such a balance progressively breaks down during ageing, when the aorta stiffens and remodels by increasing its diameter. These two degenerative processes however, have different impacts on the arterial wave pattern. They both tend to compensate for each other, thus reducing the detrimental effect they would have had if they had arisen individually. This remarkable compensatory mechanism is investigated by a validated multi-scale model, with the aim to elucidate how aortic stiffening and remodelling quantitatively impact the complex interplay between forward and reflected backward waves in the arterial network. We focus on the aorta and on the pressure at the ventricular-aortic interface, which epidemiological studies demonstrate to play a key role in cardiovascular diseases.

No MeSH data available.


Related in: MedlinePlus