Contrast Enhanced Echocardiography for Detection of Intrapulmonary Shunts in Liver Transplant Candidates

Background: Intrapulmonary vascular abnormalities associated with liver cirrhosis may result in intrapulmonary right-to-left shunt and hypoxemia. The aim of this study was to use contrast enhanced echocardiography to detect intrapulmonary vascular abnormalities in patients with liver cirrhosis candidates for liver transplantation. Methods: One hundred and two adult patients underwent contrast enhanced echocardiography to determine the prevalence of intrapulmonary right-to-left shunt and its relationship to the severity of hepatic disease, arterial oxygenation, and spider angioma. Results: The rate of patients with positive and negative contrast enhanced echocardiography was 44% and 56%, respectively. There was no significant difference in age, sex, or etiology of liver cirrhosis in patients with and without intrapulmonary shunt. Patients with intrapulmonary right-to-left shunt had more severe hepatic disease compared with those without shunt (Child-Pugh score 12±2 vs 8±2). There was significant difference in the partial arterial oxygen pressure (PaO2) values in patients with grade 3 to 4 left ventricular opacification by microbubbles compared with those without evidence of intrapulmonary right-to-left shunt (64±6 vs 82±10 mmHg). Twenty eight of the patients with intrapulmonary right-to-left shunt had cutaneous spider angioma. Conclusion: The findings suggest that there was a significant relation between severity of liver cirrhosis and presence of intrapulmonary right-to-left shunt or severity of hypoxemia. The data also indicate that cirrhotic patients with cutaneous spider angioma most likely have the shunt. Iran J Med Sci 2007; 32(1): 1-4.