TY - JOUR
T1 - Extracellular matrix fiber microarchitecture is region-specific in bicuspid aortic valve-associated ascending aortopathy
AU - D'Amore, Antonio
AU - Phillippi, Julie A.
AU - Tsamis, Alkiviadis
AU - D'Amore, Antonio
AU - Krawiec, Jeffrey T.
AU - Wagner, William R.
AU - Koch, Ryan G.
AU - Chan, Patrick G.
AU - Watkins, Simon C.
AU - Vorp, David A.
AU - Gleason, Thomas G.
PY - 2016
Y1 - 2016
N2 - Objective Ascending thoracic aortic aneurysm (ATAA) in patients with bicuspid aortic valve (BAV) commonly dilate asymmetrically compared with patients with tricuspid aortic valve (TAV). This discrepancy in aneurysm geometry led us to hypothesize that microarchitectural differences underlie the observed asymmetric dilatation pattern. The purpose of this study was to characterize the microarchitectural distinctions of the extracellular matrix of the 2 phenotypes with a focus on the proportion of radially oriented elastin and collagen fibers in different circumferential aortic regions. Methods Aortic tissue rings were obtained just distal to the sinotubular junction from patients with BAV or TAV undergoing elective aneurysm repair. They were sectioned into three circumferentially based regions according to adjacent aortic sinus segment (left coronary sinus [L], right coronary sinus [R], or noncoronary sinus [N]). Multiphoton microscopy was used to quantify and characterize the number of radially oriented elastin and collagen fibers. Results There were fewer radially oriented fibers in medial region N and medial-intimal region R of BAV-ATAAs when compared with TAV-ATAAs (medial region N, amplitude of angular undulation of elastin = 10.67° ± 1.35° vs 15.58° ± 1.91°; P =.041; medial-intimal region R, amplitude of angular undulation of elastin = 9.83° ± 0.83° vs 14.72° ± 1.64°; P =.015). Conversely, fibers became more radially oriented in the medial-intimal region L of BAV-ATAA when compared with TAV-ATAA (amplitude of angular undulation of collagen = 18.67° ± 0.95° vs 14.56° ± 1.37°; P =.041). Conclusions The differential pattern of fiber orientation noted between L and N-R regions help explain the unique pattern of greater curvature dilatation of BAV-ATAA. The distinctions noted in matrix microarchitecture may form the basis of differing aneurysm geometries and aortic wall integrities in ATAAs arising in these different valve morphologies.
AB - Objective Ascending thoracic aortic aneurysm (ATAA) in patients with bicuspid aortic valve (BAV) commonly dilate asymmetrically compared with patients with tricuspid aortic valve (TAV). This discrepancy in aneurysm geometry led us to hypothesize that microarchitectural differences underlie the observed asymmetric dilatation pattern. The purpose of this study was to characterize the microarchitectural distinctions of the extracellular matrix of the 2 phenotypes with a focus on the proportion of radially oriented elastin and collagen fibers in different circumferential aortic regions. Methods Aortic tissue rings were obtained just distal to the sinotubular junction from patients with BAV or TAV undergoing elective aneurysm repair. They were sectioned into three circumferentially based regions according to adjacent aortic sinus segment (left coronary sinus [L], right coronary sinus [R], or noncoronary sinus [N]). Multiphoton microscopy was used to quantify and characterize the number of radially oriented elastin and collagen fibers. Results There were fewer radially oriented fibers in medial region N and medial-intimal region R of BAV-ATAAs when compared with TAV-ATAAs (medial region N, amplitude of angular undulation of elastin = 10.67° ± 1.35° vs 15.58° ± 1.91°; P =.041; medial-intimal region R, amplitude of angular undulation of elastin = 9.83° ± 0.83° vs 14.72° ± 1.64°; P =.015). Conversely, fibers became more radially oriented in the medial-intimal region L of BAV-ATAA when compared with TAV-ATAA (amplitude of angular undulation of collagen = 18.67° ± 0.95° vs 14.56° ± 1.37°; P =.041). Conclusions The differential pattern of fiber orientation noted between L and N-R regions help explain the unique pattern of greater curvature dilatation of BAV-ATAA. The distinctions noted in matrix microarchitecture may form the basis of differing aneurysm geometries and aortic wall integrities in ATAAs arising in these different valve morphologies.
KW - 80 and over; Aorta
KW - Thoracic; Aortic Aneurysm
KW - Thoracic; Aortic Valve; Elasticity; Extracellular Matrix; Female; Heart Valve Diseases; Humans; Male; Middle Aged; Cardiology and Cardiovascular Medicine; Surgery; Pulmonary and Respiratory Medicine
KW - aortic wall microarchitecture; aortopathy; ascending aortic aneurysm; bicuspid aortic valve; collagen; elastin; Adult; Aged; Aged
KW - 80 and over; Aorta
KW - Thoracic; Aortic Aneurysm
KW - Thoracic; Aortic Valve; Elasticity; Extracellular Matrix; Female; Heart Valve Diseases; Humans; Male; Middle Aged; Cardiology and Cardiovascular Medicine; Surgery; Pulmonary and Respiratory Medicine
KW - aortic wall microarchitecture; aortopathy; ascending aortic aneurysm; bicuspid aortic valve; collagen; elastin; Adult; Aged; Aged
UR - http://hdl.handle.net/10447/222137
UR - http://www.elsevier.com/inca/publications/store/6/2/3/1/5/1/index.htt
M3 - Article
SN - 0022-5223
VL - 151
SP - 1718
EP - 1728
JO - Journal of Thoracic and Cardiovascular Surgery
JF - Journal of Thoracic and Cardiovascular Surgery
ER -