TRANSESOPHAGEAL ECHOCARDIOGRAPHIC ASSESSMENT OF PULMONARY VENOUS FLOWAFTER SINGLE-LUNG TRANSPLANTATION

Transesophageal echocardiography was used to evaluate pulmonary venous flow velocity and pulmonary venous diameter of both the transplanted and native lungs in six single lung transplant recipients. Mean pulmon ary venous velocity (50 +/- 10 versus 27 +/- 8 cm/sec) and pulmonary v enous diameter (1.39 +/- 0.16 versus 0.98 +/- 0.18 cm) were significan tly greater in the transplanted lung than in the native contralateral lung. An index of allograft perfusion, QD-transesophageal echocardiogr aphy (pulmonary venous velocity x pulmonary venous diameter), correlat ed highly with previously measured technetium 99m-labeled macroaggrega ted albumin quantitative lung perfusion studies (r = 0.94). A pressure gradient in pulmonary venous flow velocity across the left atrial ana stomosis was detected in two patients (8 and 12 mm Hg). Analysis of pr evious resting supine and upright incremental hemodynamic exercise tes ting showed no significant differences in these two patients with resp ect to maximum oxygen uptake, mean pulmonary arterial pressure, pulmon ary capillary wedge pressure, cardiac ind'', or pressure-flow relation ships. Therefore these left atrial anastomotic gradients did not appea r to adversely affect the pulmonary vascular response to incremental e xercise. Transesophageal echocardiography may be an invaluable techniq ue in the expedient evaluation of cardiac function and allograft perfu sion after lung transplantation.