THE EFFECTS OF OBSTRUCTING THE BLOOD-FLOW THROUGH THE PULMONARY VESSELS: AN EXPERIMENTAL STUDY IN RATS

¹ Department of Morbid Anatomy, University College Hospital Medical School, London

1. Total ligation of the left pulmonary artery by means of a new technique results in slight atrophy of the affected lung, with occasional fibrosis, new capillary formation near bronchi, and the development of fibrovascular strands between pleura and peribronchial or perivascular spaces. Bronchial arteries, pleural vessels, and vessels of pleural adhesions become congested and dilated.

2. Simultaneous ligation of the pulmonary artery and vein produces haemorrhagic infarction in the lung, with ultimate fibrosis.

3. Total ligation of the pulmonary vein leads to haemorrhagic infarction of the lung. Partial ligation of pulmonary vein often gives the same change.

4. The bearing of these experimental results on pulmonary infarction in chronic valvular diseases is discussed, and it is suggested that some lung infarcts may be due to circulatory stasis and venous thrombosis alone without the intervention of embolism.

Note:

Grateful acknowledgment is made to Professor G. R. Cameron, F. R. S., and Professor I. de Burgh Daly, F. R. S., for helpful criticisms; to Dr. J. M. Barnes for allowing me to finish this investigation at U. C. H. after joining his Unit; to Messrs. F. J. Crew and D. A. Stocker for technical assistance; and to Mr. A. Bright for the photomicrographs. The expenses were met by a grant from the Graham Fund.