Figure 1.
(A) Axial CT scan, lung window; (B) Coronal CT scan, lung window – ground-glass opacities (blue arrow A, green arrow B) with a confluent lobular pattern are visible in the right basal pyramid, involving both peribronchovascular and peripheral regions, secondary to recent episodes of haemoptysis. (C) Pulmonary arterial phase of thoracic CT revealed significant enlargement of the main pulmonary artery (blue arrow), which exceeded the diameter of the adjacent ascending aorta (red arrow) – a classic radiologic feature suggestive of PH. (D) Chest X-ray at first check-up showed hilar opacities with a polycyclic appearance. PH, pulmonary hypertension.
Figure 2.
(A) TTE in the parasternal short-axis view revealed a PAT of 58 ms. A PAT <100 ms is suggestive of PH, while values <70 ms are typically associated with severe forms. (B) Echocardiographic assessment of right ventricular function showed an RVFAC of 34.6%, below the normal range of 35%–60%, consistent with global right ventricular systolic dysfunction. (C) ECG shows rightward axis: lead I predominantly negative QRS complex, lead aVF predominantly positive QRS complex, QRS axis >+90°; (D) ECG shows R/S = 1 in V6, which means clockwise rotation associated with right ventricular hypertrophy. PAT, pulmonary acceleration time; PH, pulmonary hypertension; RVFAC, right ventricular fractional area change; TTE, transthoracic echocardiography.
Figure 3.
MIP reconstructions (coronal, sagittal, axial planes) showing multiple dilated portosystemic collateral vessels. (A) Coronal CT image showing dilatation of the pulmonary arteries (blue and purple arrows) and hypertrophy of the bronchial arteries (red arrow), as part of the compensatory mechanism associated with PoPH. (B) Sagittal reconstruction highlighting the trajectory of collateral venous circulation in portosystemic shunting pathways; (C) Axial abdominal CT reconstruction illustrating a cirrhotic liver with a nodular contour and irregular hepatic surface. Note the dilated portal vein (red arrow) and the partially visualised recanalised paraumbilical vein (yellow arrow), suggestive of PHT. (D–F) MIP reconstruction (axial, coronal, and sagittal) highlights the pulmonary arterial arborisation and extensive abdominal collateral vessels. Aberrant ascending venous pathways, likely originating from perioesophageal and diaphragmatic networks, suggest portopulmonary collateral formation potentially involved in localised pulmonary congestion or haemoptysis. MIP, maximum intensity projection; PHT, portal hypertension; PoPH, portopulmonary hypertension.
Table 1.
Diagnostic clarity between PoPH and HPS
| Feature | PoPH | HPS |
|---|---|---|
| Definition | PH occurring in the context of PHT, with or without intrinsic liver disease | Hypoxaemia due to IPVDs in patients with chronic liver disease and/or PHT |
| Prevalence (in cirrhotic patients) | PoPH, less common than HPS, is present in ~0.7% of patients with cirrhosis, 2% of patients with PHT and 5%–15% of PH cases | Affects ~30% of patients with cirrhosis; range: 4%–47% |
| Pathophysiological mechanisms | Pulmonary vasoconstriction, medial hypertrophy, intimal fibrosis and plexiform lesions due to circulating vasoactive mediators | Diffuse capillary vasodilation, increased NO production, angiogenesis, and impaired alveolar-capillary oxygen exchange |
| Diagnostic criteria | PHT, mPAP >20 mmHg, PVR >2 Wood units, PCWP ≤15 mmHg (confirmed by RHC) | Chronic liver disease or PHT, A-a gradient ≥15 mmHg (or ≥20 mmHg if ≥65 years), IPVD on CE-TTE |
| Clinical presentation | Exertional dyspnoea, fatigue and signs of right heart strain | Platypnoea, orthodeoxia, cyanosis, digital clubbing and prominent hypoxaemia |
| ECG findings | RBBB, rightward axis and RV hypertrophy | None |
| Key imaging/testing modalities | Transthoracic Doppler echocardiography followed by RHC | CE-TTE and arterial blood gas testing |
| Therapeutic strategies | Pulmonary vasodilators (PDE5 inhibitors, prostacyclin analogues, and endothelin receptor antagonists), oxygen and avoid TIPS | No proven medical therapy; supplemental oxygen and LT are mainstays. TIPS may have a transient benefit |
| LT implications | Considered for LT if mPAP is <35 mmHg or medically optimised. Perioperative mortality risk is high if mPAP is ≥45 mmHg | Indicated for LT if PaO2 is <60 mmHg. Post-transplant hypoxaemia typically resolves. Long-term prognosis is excellent |
| Prognosis | Variable. Five-year post-LT survival ranges from 63% to 67%; high early mortality risk, especially if mPAP ≥45 mmHg. Ongoing medical therapy may be required | Favourable after LT. Five-year survival ~76%, comparable to non-HPS patients; hypoxaemia typically resolves completely |
1 CE-TTE, contrast-enhanced transthoracic echocardiography; HPS, hepatopulmonary syndrome; IPVD, intrapulmonary vascular dilatation; LT, liver transplantation; mPAP, mean pulmonary arterial pressure; NO, nitric oxide; PAH, pulmonary arterial hypertension; PCWP, pulmonary capillary wedge pressure; PDE5, phosphodiesterase-5; PH, pulmonary hypertension; PHT, portal hypertension; PoPH, portopulmonary hypertension; PVR, pulmonary vascular resistance; RBBB, right bundle branch block; RHC, right heart catheterisation; RV, right ventricle; TIPS, transjugular intrahepatic portosystemic shunt.