Experimental ventricular hypertrophy in growing pigs.
An experimental model has been developed in the growing pig to study the pathology of myocardial hypertrophy. Aortopulmonary shunts were created in 4-week-old piglets and the animals were followed-up to 7 months of age. The pulmonary arterial pressure had increased at 4 weeks of shunt function by an average of 118% and the pulmonary blood flow by as much as 63%. In the longest living animal (7 months), the pulmonary arterial pressure and blood flow had increased by 170 and 53%, respectively, in relation to normal findings. The animals were killed at varying intervals and the hearts removed and examined. The weight of the entire hearts and their individual component parts increased significantly when compared with values found for normal postnatal development (P less than 0.001). The percentage increase in the total heart weights increased at all stages of development varying from an initial 109% to 39% at the time of killing. All the other parameters were also significantly greater than the values found for the normals, including the myocardial wall thickness in both ventricles (P less than 0.001). Histology showed changes comparable to gross myocardial wall thickness hypertrophy observed in human congenital anomalities. The method is recommended as a model for further studies on myocardial hypertrophy in growing individuals.
Guerreiro
D
D
Department of Biosciences, Brompton Hospital, London, U.K.
Lennox
S C
SC
Anderson
R H
RH
D000818:Animals; D006332:Cardiomegaly / Q000473:pathology*; D004195:Disease Models, Animal; D006321:Heart / Q000254:growth & development; D006801:Humans; D009206:Myocardium / Q000473:pathology*; D013552:Swine