TY - JOUR
T1 - Tissue engineering of human heart valve leaflets: a novel bioreactor for a strain-based conditioning approach
AU - Driessen - Mol, A.
AU - Driessen, N.J.B.
AU - Rutten, M.C.M.
AU - Hoerstrup, S.P.
AU - Bouten, C.V.C.
AU - Baaijens, F.P.T.
PY - 2005
Y1 - 2005
N2 - Current mechanical conditioning approaches for heart
valve tissue engineering concentrate on mimicking the opening
and closing behavior of the leaflets, either or not in combination
with tissue straining. This study describes a novel approach
by mimicking only the diastolic phase of the cardiac cycle, resulting
in tissue straining. A novel, yet simplified, bioreactor
system was developed for this purpose by applying a dynamic
pressure difference over a closed tissue engineered valve, thereby
inducing dynamic strains within the leaflets. Besides the use of
dynamic strains, the developing leaflet tissues were exposed to
prestrain induced by the use of a stented geometry. To demonstrate
the feasibility of this strain-based conditioning approach, human
heart valve leaflets were engineered and their mechanial behavior
evaluated. The actual dynamic strain magnitude in the leaflets
over time was estimated using numerical analyses. Preliminary
results showed superior tissue formation and non-linear tissuelike
mechanical properties in the strained valves when compared
to non-loaded tissue strips. In conclusion, the strain-based conditioning
approach, using both prestrain and dynamic strains, offers
new possibilities for bioreactor design and optimization of tissue
properties towards a tissue-engineered aortic human heart valve
replacement.
AB - Current mechanical conditioning approaches for heart
valve tissue engineering concentrate on mimicking the opening
and closing behavior of the leaflets, either or not in combination
with tissue straining. This study describes a novel approach
by mimicking only the diastolic phase of the cardiac cycle, resulting
in tissue straining. A novel, yet simplified, bioreactor
system was developed for this purpose by applying a dynamic
pressure difference over a closed tissue engineered valve, thereby
inducing dynamic strains within the leaflets. Besides the use of
dynamic strains, the developing leaflet tissues were exposed to
prestrain induced by the use of a stented geometry. To demonstrate
the feasibility of this strain-based conditioning approach, human
heart valve leaflets were engineered and their mechanial behavior
evaluated. The actual dynamic strain magnitude in the leaflets
over time was estimated using numerical analyses. Preliminary
results showed superior tissue formation and non-linear tissuelike
mechanical properties in the strained valves when compared
to non-loaded tissue strips. In conclusion, the strain-based conditioning
approach, using both prestrain and dynamic strains, offers
new possibilities for bioreactor design and optimization of tissue
properties towards a tissue-engineered aortic human heart valve
replacement.
U2 - 10.1007/s10439-005-8025-4
DO - 10.1007/s10439-005-8025-4
M3 - Article
C2 - 16389526
SN - 0090-6964
VL - 33
SP - 1778
EP - 1788
JO - Annals of Biomedical Engineering
JF - Annals of Biomedical Engineering
IS - 12
ER -