Bioresorbable stents

In medicine, a stent is any device which is inserted into a blood vessel or other internal duct in order to expand the vessel to prevent or alleviate a blockage. Traditionally, such devices are fabricated from metal mesh and remain in the body permanently or until removed through further surgical intervention. A bioresorbable stent serves the same purpose, but is manufactured from a resorbable or absorbable material.

Background

The use of metal drug-eluting stents presents some potential drawbacks. These include a predisposition to late stent thrombosis, prevention of late vessel adaptive or expansive remodeling, hindrance of surgical revascularization, and impairment of imaging with multislice CT.[1][2]

To overcome some of these potential drawbacks, several companies are pursuing the development of bioresorbable or bioabsorbable stents. Like metal stents, placement of a bioresorbable stent will restore blood flow and support the vessel through the healing process. However, in the case of a bioresorbable stent, the stent will gradually resorb and be benignly cleared from the body, leaving no permanent implant.

Studies have shown that the most critical period of vessel healing is largely complete by approximately three months[3][4]. Therefore, the goal of a bioresorbable or “temporary” stent is to fully support the vessel during this critical period, and then resorb from the body when it is no longer needed.

As of September, 2009, bioresorbable stents were limited to clinical investigational use only and had not yet been approved for sale.

References

  1. ^ Serruys, PW; Ormiston JA, Onuma Y, et al. (14 March 2009). "A bioabsorbable everolimus-eluting coronary stent system (ABSORB): 2-year outcomes and results from multiple imaging methods". Lancet 373 (9667): 897–910. doi:10.1016/S0140-6736(09)60325-1. PMID 19286089. 
  2. ^ Ormiston, JA; Serruys PW, Regar E et al. (15 March 2008). "A bioabsorbable everolimus-eluting coronary stent system for patients with single de-novo coronary artery lesions (ABSORB): a prospective open-label trial". Lancet 371 (9616): 899–907. doi:10.1016/S0140-6736(08)60415-8. PMID 18342684. 
  3. ^ Serruys, PW; Luijten HE, Beatt KJ, et al. (February 1988). "Incidence of restenosis after successful coronary angioplasty: a time-related phenomenon. A quantitative angiographic study in 342 consecutive patients at 1, 2, 3, and 4 months.". Circulation 77 (2): 361–71. PMID 2962786. 
  4. ^ Post, MJ; Borst C, Kuntz RE (1994). "The relative importance of arterial remodeling compared with intimal hyperplasia in lumen renarrowing after balloon angioplasty: a study in the normal rabbit and the hypercholesterolemic Yucatan micropig". Circulation 89 (6): 2816–2821. PMID 8205696.