Changes in the Pulmonary Circulation before and after Operation for the Pulmonary Cancer

　1)　In the lung cancer, the intrapulmo-nary distribution of the ventilation is often　impaired and the pulmonary blood flow　decreased．　However, some cases showed　a state of high output failure, being accom-panied by the higher level of the pulmo-nary blood flow than the normal.　The　pulmonary arterial pressure elevated slight-ly or moderately in these cases, as the　pulmonary vascular bed had a sufficient　compensatory response.　But in almost all　the cases of the lung cancer, work of the　right ventricle for the pressure increased　and the right ventricular debt occurred　eminently.