Impact of Stenting on PDA Length, Curvature, and Pulsatile Deformations Based on CT Assessment

Abstract

Background: We sought to investigate the impact of stenting on native patent ductus arteriosus (PDA) length, curvature, and pulsatile deformations in patients with ductal-dependent pulmonary circulations.

Methods: Patients with PDA stents who received contrast-enhanced 3-dimensional computed tomography with a view of the PDA, thoracic aorta, and pulmonary arteries were retrospectively included in this study. Geometric models of the prestented and poststented PDA were constructed from the computed tomography images, and PDA arclength, curvature, and pulsatile deformations were quantified.

Results: A total of 12 patients with cyanotic congenital heart disease were included, 10 of whom received 1 stent in the PDA and 2 received multiple overlapping stents. From prestenting to poststenting, the PDA shortened by 26 ± 18% (P = .004) and decreased in mean and peak curvature by 60 ± 21% and 68 ± 15%, respectively (both P < .001). Pulsatile deformations varied highly for the native PDA, stented PDA, and stents themselves.

Conclusions: The shortening and straightening of the PDA after stenting are significant and substantial, and their quantitative characterization will enable interventionalists to select stent lengths that span the entire PDA without encroaching on the aortic or pulmonary artery, which could cause hemodynamic interference, stent kink, and fatigue. Pulsatile PDA deformations can be used to design and evaluate devices tailored to congenital heart disease in neonates.

Keywords: device durability; device selection; ductal-dependent circulation; patent ductus arteriosus; preoperative planning; stenting.

Graphical abstract

Figure 1

Geometric modeling of the aorta, pulmonary arteries, and patent ductus arteriosus. (A) Manual centerline path selection of the aorta, left pulmonary artery (LPA), main pulmonary artery continuing to the right pulmonary artery (MPA-RPA), and the patent ductus arteriosus (PDA) connecting the aorta to the LPA. (B) Cross-sectional contour segmentation of the native and stented PDA. (C) Contours of the aorta, pulmonary arteries, and PDA.

Central Illustration

Patent ductus arteriosus geometric models from computed tomography angiography. Geometric models of the native aorta, pulmonary arteries, and native- (left) and stented- (right) patent ductus arteriosus (PDA). The full stent is visualized in gray and is often protruding into the aortic and pulmonary sides (middle-top and right). From presenting to poststenting the PDA was significantly straightened and shortened, as visualized (middle-bottom).

Figure 2

Schematic definitions of quantified metrics. Arclength is defined for the vessel/stent centerline, the longitudinal curvature (κ) using a sliding window (w) with curvature defined as the inverse of the fitted circle’s radius (R), and the cross-sectional effective diameter (D_eff) computed from the cross-sectional area (light gray).

Figure 3

In 8 patients, 3-dimensional models of native (top row) and stented (bottom row) patent ductus arteriosus were analyzed. In the left 4 columns, the surface models shown are from nongated (diastole-weighted) images, while in the right 4 columns, the surface models are the diastole models from gated images.

Figure 4

Images from double-oblique planes cutting through (A-C) the stented PDA and (D) 3-dimensional stent model for case 4 where the stent abuts against the vessel wall of the left pulmonary artery (yellow #), leading to stent kinking (red arrow) in the lumen of the pulmonary artery. The right pulmonary artery (yellow +), aorta (purple §), and stented PDA (red ∗) are also marked.