Secondary Pulmonary Vein Stenosis Due to Total Anomalous Pulmonary Venous Connection Repair in Children: Extravascular MDCT Findings

Abstract

Purpose: To evaluate extravascular findings on thoracic MDCT angiography in secondary pulmonary vein stenosis (PVS) due to total anomalous pulmonary venous connection (TAPVC) repair in children. Materials and Methods: All patients aged ≤18 years with a known diagnosis of secondary PVS after TAPVC repair, confirmed by echocardiography, conventional angiography, and/or surgery, who underwent thoracic MDCT angiography studies between July 2008 and April 2021 were included. Two pediatric radiologists independently examined MDCT angiography studies for the presence of extravascular thoracic abnormalities in the lung, pleura, and mediastinum. The location and distribution of each abnormality (in relation to the location of PVS) were also evaluated. Interobserver agreement between the two independent pediatric radiology reviewers was studied using kappa statistics. Results: The study group consisted of 20 consecutive pediatric patients (17 males, 3 females) with secondary PVS due to TAPVC repair. Age ranged from 2 months to 8 years (mean, 16.1 months). In children with secondary PVS due to TAPVC repair, the characteristic extravascular thoracic MDCT angiography findings were ground-glass opacity (19/20; 95%), septal thickening (7/20; 35%), pleural thickening (17/20; 85%), and a poorly defined, mildly heterogeneously enhancing, non-calcified soft tissue mass (17/20; 85%) which followed the contours of affected pulmonary veins outside the lung. There was excellent interobserver kappa agreement between two independent reviewers for detecting extravascular abnormalities on thoracic MDCT angiography studies (k = 0.99). Conclusion: Our study characterizes the extravascular thoracic MDCT angiography findings in secondary pediatric PVS due to TAPVC repair. In the lungs and pleura, ground-glass opacity, interlobular septal thickening, and pleural thickening are common findings. Importantly, the presence of a mildly heterogeneously enhancing, non-calcified mediastinal soft tissue mass in the distribution of the PVS is a novel characteristic thoracic MDCT angiography finding seen in pediatric secondary PVS due to TAPVC repair.

Pleuropulmonary MDCT Findings: Comparison between Children with Pulmonary Vein Stenosis and Prematurity-Related Lung Disease

“…The findings of our study correlate well with the findings from previously published studies in pediatric patients with primary and secondary PVS focusing on extrathoracic MDCT findings [16][17][18]. These studies also identified the presence of three main extravascular pleuropulmonary abnormalities on thoracic MDCT in pediatric patients with PVS: GGO, septal thickening, and pleural thickening.…”

“…Presented clinical signs and symptoms in these 49 pediatric patients included: failure to thrive (n = 8; 16.3%), pulmonary hypertension (n = 7; 14.3%), shortness of breath (n = 5; 10.2%), hypoxemia (n = 5; 10.2%), fever (n = 3; 6.1%), and bradycardia (n = 2; 4.1%). Extrapulmonary MDCT findings for a subset of these patients were previously reported [16][17][18].…”

“…Prematurity was defined as born alive before 37 weeks of pregnancy [22]. The PVS diagnostic criterion was pulmonary vein luminal narrowing in ≥2 vessels with a mean gradient ≥ 4 mm Hg seen on echocardiography or conventional angiography [16][17][18] 5) a 256-MDCT scanner (n = 2; 4%); and (6) a 302-MDCT scanner (n = 1; 5%).…”

“…Recently, there has been an important paradigm shift in the imaging evaluation of pediatric PVS, change from solely focusing on the identification of affected pulmonary veins to also visualizing the characteristic extravascular thoracic findings of PVS in pediatric patients [16][17][18]. Identification of the characteristic extravascular thoracic findings of PVS in children is important because it can both confirm the diagnosis of PVS (when a narrowed pulmonary vein is visualized or suspected), and it can also suggest the diagnosis of PVS on MDCT studies that were not technically optimized for evaluation of the pulmonary veins.…”

“…Furthermore, this new focus on "seeing the bigger picture" of PVS has improved our understanding of the pathophysiology of this elusive disease. In children with PVS, thoracic MDCT often visualizes a soft tissue proliferation along the pulmonary veins (likely corresponding to the myofibroblast-like proliferation) as well as interlobular septal thickening and alveolar ground-glass opacity (GGO) attributed to decreased pulmonary venous drainage (due to narrowed pulmonary veins) [16][17][18].…”