Hepatopulmonary syndrome is a serious pulmonary vascular complication in patients with chronic liver disease. It constitutes a triad of chronic liver disease, increased alveolar-arterial oxygen gradient, and evidence of intrapulmonary shunt (IPS). The diagnosis of IPS can be made by bubble echocardiography, technetium-99m-labeled macroaggregated albumin (99mTc-MAA) scintigraphy or pulmonary arteriography. Though echocardiography is a sensitive screening test, MAA scintigraphy can also quantify the extent of shunting.
