Intrapulmonary vascular dilatations (IPVD) in liver transplant candidates. Screening by two-dimensional contrast-enhanced echocardiography

Intrapulmonary vascular dilatations (IPVD) are extrahepatic complications of acute and chronic liver disorders that can result in severe hypoxemia. Contrast-enhanced (CE) echocardiography provides a noninvasive method to detect right-to-left shunting associated with IPVD. We prospectively studied 40 consecutive liver transplant candidates to determine the relationship between CE echocardiography, arterial blood gases, and standard pulmonary function tests. Two patients had technically unacceptable results of echocardiographic studies. Thirty-eight patients had acceptable results of studies; seven (18.4 percent) of 38 were hypoxemic (PaO₂ < 70 mm Hg). Thirty-one patients (81.6 percent) had PaO₂ ≥ 70 mm Hg. Positive CE echocardiograms suggesting IPVD were found in five (13.2 percent) of 38. Three (9.7 percent) of the 31 patients with PaO₂ ≥ 70 mm Hg had positive CE echocardiograms. Two (28.6 percent) of the seven hypoxemic patients had positve CE echocardiography. Mean PaO₂ and pulmonary function parameters were not significantly different between those with positive CE echocardiogram compared with those with normal CE echocardiograms. We conclude that for our group of liver transplant candidates, (1) IPVD as suggested by CE echocardiography were not uncommon (13.2 percent), and (2) positive CE echocardiography could be documented in patients who were not hypoxemic (9.7 percent).