In all four cases, pulmonary vein stenosis was identified several months after atrial fibrillation ablation, in keeping with the delayed nature of post-procedural venous remodelling described in the literature. The left-sided pulmonary veins were predominantly affected, most commonly the left superior pulmonary vein, consistent with previously reported anatomical and procedural susceptibility. The severity of involvement ranged from high-grade focal stenosis to complete venous occlusion.

Direct imaging findings included marked narrowing of the pulmonary vein lumen, abrupt termination of contrast opacification, and reduced or absent enhancement distal to the stenotic segment. These abnormalities were best demonstrated on contrast-enhanced computed tomography using multiplanar and maximum intensity projection reconstructions, which allowed comprehensive assessment of the pulmonary veins along their longitudinal axis. Three-dimensional reconstructions provided additional value by facilitating spatial orientation and confirming the extent of venous involvement.

In addition to direct venous abnormalities, all cases demonstrated indirect pulmonary findings within the drainage territory of the affected vein. These included regional ground-glass opacities, subpleural or segmental consolidation, interlobular septal thickening, and areas suggestive of venous congestion or infarction. In some patients, these parenchymal abnormalities were the predominant imaging feature at presentation and initially prompted alternative diagnostic considerations.

The temporal evolution of imaging findings varied between patients. In certain cases, pulmonary parenchymal changes preceded definitive recognition of pulmonary vein stenosis, contributing to delayed diagnosis. As described in previous studies, these indirect findings showed fluctuation over time, reflecting dynamic changes in venous pressure and pulmonary perfusion. Perfusion asymmetry and delayed contrast transit within the affected lung segments further supported the haemodynamic consequences of venous obstruction.

Clinical presentation was heterogeneous, ranging from exertional dyspnoea and chest discomfort to haemoptysis, while some patients reported only mild or nonspecific symptoms. This variability was disproportionate to the degree of venous narrowing observed on imaging, reinforcing the limited correlation between symptom severity and anatomical stenosis. The combination of nonspecific symptoms and overlapping imaging findings contributed to diagnostic complexity in several cases.