Early stenting with serial dilations in a swine coarctation model prevented blood pressure gradients and adverse remodeling, but 4 of 6 stented animals developed peri-stent aneurysms.
Does early stent implantation with serial dilation prevent adverse cardiovascular remodeling in a porcine model of coarctation?
In a porcine model, early coarctation stenting with serial dilations prevented adverse myocardial remodeling but was frequently complicated by peri-stent aneurysms.
ABSTRACT Background Novel stent technologies offer early intravascular treatment options for coarctation (COA). Mid‐to‐long‐term cardiovascular responses to early COA stent interventions are undefined. Aims We studied a porcine model of COA, with and without early stent implantation with serial dilation to adult aortic diameters, aiming to define longitudinal cardiovascular changes. Methods In total, 18 swine were studied: 6 shams, 6 COA controls (CC), and 6 COA stents (CS). Surgical COA was induced at 2 weeks (4.5 kg) followed by stent implant at 6 weeks, with serial dilations at 12 and 20 weeks (80 kg). All animals were terminally studied at 20 weeks. Results Successful stent implantation with serial dilation matching somatic growth occurred in all CS animals with predictable stent performance and elimination of COA. No in‐stent stenosis observed. Final stent dimensions equaled the proximal descending aorta (DAo) of shams (16.8 ± 1.5 vs. 17.5 ± 0.8, p = 0.3); however, DAo narrowing (13.3 ± 1.1 mm) just distal to the stent without gradient was created because of stent shortening, and this DAo segment demonstrated decreased vessel wall collagen content. Four of 6 animals developed peri‐stent aneurysms treated with covered stents. CS prevented post stenotic dilation and collateralization and resulted in near normalization of catheter‐derived hemodynamics. Cardiac MRI documented similar ventricular function, cardiac index, and myocardial tissue characterization between groups. Early COA stenting was associated with increased systemic arterial elastin content. Conclusion In this swine COA model, early stent implants effectively dilated to adult aortic dimensions, prevented blood pressure gradients, collateralization, and adverse myocardial remodeling. Early stenting with serial dilations altered systemic arterial elastin content, and additional stents may be necessary to enlarge the adjacent DAo. Aneurysm formation frequently occurred.
Gober et al. (Sun,) conducted a other in Coarctation of the aorta (n=18). Early stent implantation with serial dilation vs. Sham surgery and COA controls was evaluated on Longitudinal cardiovascular changes. Early stenting with serial dilations in a swine coarctation model prevented blood pressure gradients and adverse remodeling, but 4 of 6 stented animals developed peri-stent aneurysms.