Abstract Background Hepatopulmonary syndrome (HPS) is a rare complication of chronic liver disease defined by the triad of liver dysfunction, arterial hypoxemia, and intrapulmonary vascular dilatations (IPVDs). The hallmark feature is oxygenation impairment due to pulmonary vasodilatation leading to right to left intrapulmonary shunting. Recognition of HPS is clinically important and liver transplantation remains the only definitive therapy. Contrast transthoracic echocardiography (TTE) with agitated saline is the most sensitive noninvasive tool for detecting intrapulmonary shunting. Case Presentation A 66-year-old female with a history of alcohol-related cirrhosis, heart failure with reduced ejection fraction (25%), portal hypertension, and prior esophageal varices presented with progressive dyspnea and persistent hypoxemia. On arrival, she required high-flow nasal cannula to maintain oxygen saturation above 88%. Chest CT revealed mild bilateral basal reticular opacities without consolidation or significant effusions. Infectious and thromboembolic causes were excluded, with negative COVID-19 and respiratory panels and a CT angiogram showing no pulmonary embolism.Given her chronic liver disease and unexplained hypoxemia, a contrast-enhanced TTE was performed. Following injection of agitated saline, microbubbles appeared in the left atrium and ventricle after 3-4 cardiac cycles—consistent with delayed transit through dilated pulmonary capillaries rather than an intracardiac shunt such as a patent foramen ovale. This delayed appearance pattern confirmed the presence of intrapulmonary vascular dilatation, establishing the diagnosis of hepatopulmonary syndrome. Discussion Hepatopulmonary syndrome results from pulmonary capillary dilation driven by increased nitric oxide and endothelin-1 activity in chronic liver disease. The diagnostic criteria include: (1) chronic liver disease or portal hypertension, (2) arterial hypoxemia (PaO2 80 mmHg or A-a gradient 15 mmHg), and (3) evidence of intrapulmonary shunting. Contrast echocardiography plays a diagnostic role, as the delayed bubble appearance (≥3 cardiac cycles) distinguishes intrapulmonary from intracardiac shunts. Other adjunctive tests include arterial blood gases, lung perfusion scanning, and orthodeoxia assessment.This case underscores the importance of maintaining a high index of suspicion for HPS in cirrhotic patients presenting with unexplained hypoxemia. Early identification using contrast echocardiography facilitates timely evaluation for liver transplantation—the only curative option—and helps prevent morbidity associated with advanced hypoxemia. Management is primarily focused on optimizing oxygenation and evaluating candidacy for liver transplant evaluation. In most cases, resolution of HPS occur within 6-12 months post transplant. This abstract is funded by: none
Biscuitwala et al. (Fri,) studied this question.