Author + information
- Received July 24, 1997
- Revision received January 16, 1998
- Accepted January 26, 1998
- Published online May 1, 1998.
- Charles J McKenna, MB, MRCPA,
- Allan R Camrud, RNA,
- Giuseppe Sangiorgi, MDA,
- Hyuck M Kwon, MDA,
- William D Edwards, MD, FACCB,
- David R Holmes Jr, MD, FACCB and
- Robert S Schwartz, MD, FACCA,*
- ↵*Dr. Robert S. Schwartz, Mayo Clinic Cardiology, SMH 4523, 200 First Street, SW, Rochester, Minnesota 55905.
Objectives. This study was designed to test the efficacy and safety of a fibrin-film–covered stent compared with that of a bare metal stent in the porcine coronary injury model.
Background. Biodegradable stents are a potential method of achieving total lesion coverage and delivering local, lesion-specific drug therapy.
Methods. Two coronary arteries in each pig were randomly assigned to deployment of either a fibrin-film or a bare tantalum wire-coil stent. An oversized balloon injury, 1.15 to 1.30 times the reference vessel diameter, was induced in each coronary segment before stenting to simulate angioplasty injury. Thirty pigs were studied: group 1 for 28 days (15 pigs); group 2 for 90 days (5 pigs); group 3 for 6 months (5 pigs); group 4 for 1 year (5 pigs).
Results. Two pigs died of occlusion of the bare stent and one of occlusion of the fibrin stent (p > 0.99). There were no significant differences between the fibrin-stented and bare-stented coronary segments with regard to arterial injury. In group 1 (28 days, 14 pigs), the mean neointimal thicknesses in the fibrin-stented and bare-stented groups were 0.57 ± 0.31 and 0.57 ± 0.27 mm, respectively (p = 0.89). In groups 2 to 4 (90 days, four pigs; 6 months, four pigs; 1 year, five pigs), the mean neointimal thicknesses for fibrin- and bare-stented coronary segments at the times studied were 0.48 ± 0.26 versus 0.50 ± 0.22 mm at 90 days; 0.35 ± 0.04 versus 0.35 ± 0.16 mm at 6 months; and 0.33 ± 0.14 versus 0.30 ± 0.14 mm at 1 year (p = 0.98).
Conclusions. Fibrin-film stents appear to be an excellent candidate for local drug delivery because they can completely and safely cover the stented coronary segment while degrading slowly over 1 to 3 months. This result is important when compared with the poor results of previous studies of synthetic polymer stents.
- Received July 24, 1997.
- Revision received January 16, 1998.
- Accepted January 26, 1998.
- The American College of Cardiology