Effects of Pulmonary Allotransplantation in Dogs with Microembolic Pulmonary Hypertension

Abstract

Glass bead embolization was employed in 42 dogs to produce pulmonary hypertension prior to allotransplantation of a normal left lung. There was an early mortality of 48% after beads were administered, but survivors showed pulmonary hypertension for three to four weeks and variable effects on pulmonary function. Of 17 surviving animals that received unselected normal canine left lungs, 12 lived longer than 48 hours with evidence of progressive hemodynamic benefit in comparison with nonoperated controls. Surviving animals showed decreases in mean pulmonary artery pressure and pulmonary vascular resistance and increased resting cardiac output. Respiratory function changes induced by embolization, including hypoxia, elevated dead space/tidal volume ratios, and increased alveolar-arterial oxygen tension gradients, were not improved consistently by allotransplantation during the period of observation.