[Establishment of a cyanotic congenital heart defect porcine model with decreased pulmonary blood flow].
OBJECTIVE
To establish a porcine model of congenital heart disease with decreased pulmonary blood to explore the morphological changes of immature pulmonary vascular vessels.


METHODS
Twenty piglets (one to two-month-old) were randomly divided into three groups: sham-operated group (group S, n = 6), small incisions on the right chest, produced a transient reduction in pulmonary blood; Operation group 1(group T(1), n = 7), small incisions on the right chest, producing artificial atrial defect with self-made dilator and simultaneous banding pulmonary artery to generate a systolic pressure gradient between 20 - 30 mm Hg (1 m Hg = 0.133 kPa); Operation group 2(group T(2), n = 7): operation procedure was similar as group T(1) with systolic pressure gradient between 30 - 50 mm Hg. Lung tissue from right middle lobe (1.0 cm×0.8 cm×0.8 cm) was taken immediately after thoracotomy, at the end of surgery and at 2 months after operation and stained by Weigert (elastic fiber) and van Gieson (collagen) methods to observe the morphological changes.


RESULTS
Five animals survived in Group S, 6 animals survived in group T(1) and 5 animals survived in group T(2). The inside diameter of pulmonary arterioles after thoracotomy and at the end of surgery was similar among the three groups (P > 0.05). At 2 months after operation, the inside diameter of pulmonary artery was significantly higher in group T(1) and T(2) than in group S (all P < 0.05) while the number of pulmonary small artery per square centimeter (APSC) of group T(1) and T(2) was significantly lower than that of group S (all P < 0.05). Tunica media of pulmonary artery was thinner and vascular lumen was larger in group T(1) and T(2) compared to those of group S.


CONCLUSIONS
In this piglets model with reduced pulmonary blood, the pulmonary arterioles underwent dysplastic changes. Thus, pulmonary blood flow is an important determinant for the physiological development of pulmonary artery.
Department of Thoracic and Cardiovascular Surgery, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China. wangkangwu0552@126.com
Kang-wu
KW
Wang
Xue-gang
XG
Liu
Chao
C
Shi
Ge
G
Liu
Lei
L
Zhang
An-sheng
AS
Wang
Chao
C
Song
D000818:Animals; D001794:Blood Pressure; D003490:Cyanosis; D006330:Heart Defects, Congenital / Q000473:pathology*; D006439:Hemodynamics; D008168:Lung; D023421:Models, Animal; D011651:Pulmonary Artery / Q000503:physiopathology; D011652:Pulmonary Circulation; D013552:Swine