Abstract
Hepatopulmonary syndrome (HPS) causes hypoxemia due to intrapulmonary shunting in patients with liver disease or portal hypertension. Its recognition can be challenging when decompensated heart failure coexists and mimics or masks the true mechanism of gas-exchange failure. We report the case of a 65‑year‑old man with a history of heavy alcohol consumption, who was diagnosed with alcoholic liver cirrhosis (Child-Pugh class C, model for end-stage liver disease (MELD) score of 24) with portal hypertension, esophageal varices (Paquet grade III), and mild ascites. Past medical history was notable for dilated alcoholic cardiomyopathy, heart failure with reduced ejection fraction (New York Heart Association (NYHA) class II, left ventricle ejection fraction (LVEF) 30%), permanent atrial fibrillation (AF) (on bisoprolol and anticoagulation with acenocoumarol), and a prior mitral valve prosthesis. The patient presented with a one-week history of marked weakness and progressive dyspnea (initially exertional, later at rest on admission, and not position-dependent), without other symptoms. Upon admission, profound hypoxemia was discovered (arterial blood gas (ABG) showed pH 7.399, arterial partial pressure of oxygen (PaO(2)) 31 mmHg, arterial partial pressure of carbon dioxide (PaCO(2)) 28 mmHg, arterial oxygen saturation (SaO(2)) 55% on 15 L/min oxygen via non‑rebreather mask). Chest radiography demonstrated cardiomegaly with interstitial markings and blunted costophrenic angles, while lung ultrasound revealed diffuse B‑lines and small bilateral effusions. Focused transthoracic echocardiography showed severe biatrial/biventricular enlargement, LVEF ~31%, markedly elevated left ventricular filling pressure (E 170 cm/s, E/e' 31), high probability of pulmonary hypertension (maximal tricuspid regurgitation velocity (TR Vmax) 3.4 m/s, tricuspid regurgitation pressure gradient (TRPG) 46 mmHg), an intact mitral prosthesis, and no septal defects. Taken together, the findings were consistent with cardiogenic pulmonary edema. However, despite high-flow nasal oxygen therapy, subsequent noninvasive ventilation(NIV) (fraction of inspired oxygen (FiO₂) 1.0), and pharmacologic therapy with furosemide resulting in satisfactory diuresis (250 mL/h) and reduced pulmonary congestion on lung ultrasound, oxygenation improved only minimally (PaO₂ up to 40 mmHg), and dyspnea persisted. Given the presence of cirrhosis with portal hypertension and refractory hypoxemia, and that a workup for HPS had not yet been performed, a bedside agitated-saline contrast echocardiography was performed at the point of care. Microbubbles appeared in the left atrium (LA) and ventricle (LV)after approximately five cardiac cycles, indicating an intrapulmonary right‑to‑left shunt, thus establishing the diagnosis of HPS. The patient was not a candidate for liver transplantation; transjugular intrahepatic portosystemic shunt (TIPS) was unavailable, and transfer was unsafe. Supportive care, IV diuretics, and palliative measures were provided, but the patient died about 48 hours after admission. This case highlights how decompensated heart failure can confound and delay recognition of HPS by creating an overlapping cardiogenic phenotype. When oxygenation remains refractory despite appropriate heart failure therapy, a bedside agitated‑saline 'bubble' study, interpreted with attention to bubble‑arrival timing, can unmask intrapulmonary shunting and expedite diagnosis of HPS in unstable patients.