Pulmonary Artery Wall Thickness Assessed by Optical Coherence Tomography Correlates With Pulmonary Hemodynamics in Children With Congenital Heart Disease

Background: Pulmonary arterial (PA) wall thickening evaluated by optical coherence tomography (OCT) has been reported in adults with PA hypertension. The purpose of this study was to evaluate the feasibility of OCT for preoperative assessment of the PA wall in children with congenital heart disease (CHD).
Methods and Results: Participants comprised 39 patients with ventricular septal defect, atrial septal defect, or patent ductus arteriosus. Attempts were made to evaluate vessels of various diameters using OCT. Clearly observed vessels that were optimal for evaluation were selected and classified into 4 subgroups by diameter of the lumen. Optimal depiction was obtained in 80 of 156 vessels in total, and 25 (64.1%), 34 (87.1%), 17 (43.6%), and 4 vessels (10.3%) in each of the 1.0–<2.0 mm, 2.0–<3.0 mm, 3.0–<4.0 mm, and 4.0–5.0 mm subgroups, respectively. Arterial walls in the 2.0–<3.0 mm subgroup were the most frequently delineated, and wall thickness correlated significantly with mean PA pressure, pulmonary vascular resistance index, pulmonary-to-systemic flow ratio, and PA capacitance index (r=0.56, 0.52, 0.37, and −0.49, respectively). The 3-layered appearance was delineated in 29 of 80 vessels (36.2%). This feature had no significant correlation with pulmonary hemodynamics.
Conclusions: OCT represents a promising tool for evaluating the PA wall in children with CHD.