Characteristics and Success of Intentional Stent Fracture in Drug-Eluting Coronary Stents for Use in Congenital Heart Disease

Objectives Intravascular stenting in congenital heart disease (CHD) is a treatment modality that must account for patient somatic growth and future re-intervention. Stent expansion and intentional fracture can be performed safely and effectively. Limited understanding and data exist for drug-eluting coronary stents (DES). This study describes a serial dilation technique and characterizes dilation and fracture patterns of contemporary DES platforms. Methods Using a standardized protocol designed to minimize foreshortening, five contemporary (DES) platforms were dilated with high pressure (HPB) ultra-high-pressure balloons (UHPB) until fracture or non-fracture. Stent fracture type and characteristics of each stent tested were described. Results A total of 61 stents were tested: Resolute Onyx small (3.5 -4.0mm, n = 9, 15%), Resolute Onyx large (4.5–5.0mm, n = 11, 18%), Synergy XD (3.5–4.0mm, n = 13, 21%), Synergy Megatron (3.5–5.0mm, n = 15, 25%), and Xience Skypoint (3.5–5.0mm, n = 13, 21%). The majority of stents (57/61, 93%) were serially dilated to complete fracture, and a minority (4/61, 7%) of stents failed to fracture and foreshortened to a napkin-ring configuration. Initial stent fracture occurred at a median balloon pressure of 15atm (range 5–30atm). Conclusions Serial dilation of DES platforms using a standardized serial dilation protocol results in a high rate of intentional fracture with minimal foreshortening in ex-vivo bench testing. These results may aid congenital interventional cardiologists using DES for CHD in the selection of stents and optimal techniques for intentional fracture in vivo.