Use of a mechanical crimper for mounting covered stents in aortic coarctation

Background

Despite the continued evolution in use of covered stents in congenital cardiology, no standard technique is available for crimping stents onto balloons.

Objectives

We aimed to describe the use of a mechanical crimper to mount covered stents and its effects on stent integrity, uniformity, and sheath size for intervention.

Methods

Single-center retrospective review of patients with coarctation of the aorta (CoA) and variants of arch obstruction undergoing stent angioplasty with covered stents between January 2019 and December 2022. Sheath size used for intervention was recorded and compared to the manufacturers' IFU. A bench testing model was then performed to confirm the decrease in sheath size by mechanically crimping six covered stents. Percent reduction in size after crimping, stent uniformity, and PTFE integrity after balloon inflation were recorded.

Results

Twenty-five events were identified for review. Median age at procedure was 18 years, and the most common diagnosis was isolated CoA (80 %). 76 % (n = 19) of stents were mechanically crimped, and 24 % (n = 6) were manually crimped. The median sheath size for mechanically crimped stents was −2 Fr compared with a median of 0 Fr for manually crimped stents (p = 0.007). Bench testing revealed a median 12.8 % reduction in stent diameter after mechanical crimping. All mechanically crimped stents were successfully introduced through sheaths 2 Fr smaller than the IFU.

Conclusion

The use of mechanical crimpers for mounting covered endovascular stents allows the delivery of these devices through smaller profile sheaths, facilitating intervention in smaller patients and reducing the risk of vascular access related injuries without affecting stent performance.