research
Stents and Vascular Woundhealing
- Publication date
- 24 November 1999
- Publisher
- For many years, percutaneous trans luminal coronary angioplasty (PTCA) has been
used to treat diseased, llanowed vessels. While it has been a great success in improving
patient outcome, the teciUlique is not free from complications: restenosis, dissections and
abmpt closures are serious complications of the technique, necessitating repeat
revascularization or surgery. ExpeIimental animal studies suggested that the results of PTCA
could be improved by scaffolding the intemal wall of the artery with a stent, an idea first
proposed in 1912 by Carre. In the late 1960's Dotter gave new impetus to this idea, and in
1986 the first human coronary stent implantation followed.
Initial stent implantations were associated with high thrombosis rates and results of
stent trials were greeted cautiously or even skeptically by some. In 1994 however, the results
of the European BENES TENT and American STRESS trials were published. In these trials
restenosis rates after balloon angiopiasty or Palmaz-Schatz stent implantation were
compared, and showed significant reductions in restenosis rates after stenting (BENESTENT:
22%; STRESS: 32%) compared to angioplasty alone (BENESTENT: 32%; STRESS: 42%).
These landmark trials heralded the start of an exponential growth in the use of endovascular
stents, such that today, stenting has become accepted as a standard therapeutic modality in
interventional cardiology.
Current clinical indications for the use ofstents include: (1) the primary reduction in
restenosis in de novo focal lesions in vessels greater then 3.0 mm in diameter, (2) focal
lesions in saphenous vein grafts and (3) the treatment of abmpt or threatened vessel closure
during angioplasty. However, as the variety and sophistication of stenting devices improves,
new applications are being found. Currently there are more than 55 standard or customized
stent types available for use in the coronary system manufactured by more than 30 different
companies.