Randomized trials on PTCA and stenting in the treatment of De Novo coronary artery stenosis: an overview on existing data in June 1994.

This is a review on prospective randomized comparisons of PTCA and stents in the treatment of de novo native coronary artery lesions. BENESTENT and STRESS, two multicentric studies, used the articulated Palmaz-Schatz stent. In Lausanne, a single center trial limited to right coronary artery lesions, was conducted using the Wiktor stent. During the in-hospital phase. BENESTENT and STRESS showed the composite clinical end point to be less in the stent than in the PTCA groups (p < 0.05). In Lausanne, there was no difference between groups. The incidence of subacute closure was similar with both treatments in three trials. Angiographically, both postprocedural minimal luminal diameter (MLD) and percentage stenosis were larger in the stent group (P < 0.05). At 6 months, in both BENESTENT and STRESS, a composite clinical end point was reached by less stent patients than PTCA patients, with a reduced need for repeat nonsurgical reintervention by stenting. However, in Lausanne, there was no difference between stent and PTCA groups. At 6 months in both BENESTENT and STRESS, a persistent lower MLD, a larger percentage of stenosis, and a higher incidence of angiographic restenosis were found in the PTCA groups (P < 0.05). In Lausanne, no differences in MLD, percentage stenosis and angiographic restenosis were found between groups. Effective stenting of de novo lesions does improve immediate results compared to conventional balloon PTCA. The long-term outcome of stenting with Palmaz-Scharz stents is also improved compared to PTCA

Résultats cliniques et angiographiques immédiats et à moyen terme après l'implantation de microprothèses endocoronaires AVE chez 140 patients consécutifs. Expérience lausannoise [Immediate and mid-term clinical and angiographic results after implantation of AVE intracoronary micro-stents in 140 consecutive cases. An experience in Lausanne].

Two hundred AVE (Arterial Vascular Engineering) microstents measuring 4 to 30 mm were implanted in 140 patients aged 62 +/- 10 years with Class II to IV angina of the Canadian Cardiovascular Society Classification. The indications were: de novo lesions (30%), suboptimal angioplasty results (54%), acute occlusion (8%) or restenosis (8%). The stents of 3.0 to 4.0 mm diameter were implanted in the left main coronary artery (1%) the left anterior descending artery (20%), the left circumflex artery (19%), the right coronary artery (44%) or a venous bypass graft (7%) after intravenous injection of 15,000 IU of heparin. Daily treatment with aspirin 100 mg and ticlopidine 500 mg was instituted from the day of the procedure. The success rate was 98.5% with only 3 technical failures. The minimal luminal diameter and percentage stenosis ranged from 0.80 +/- 0.2 mm and 74 +/- 13% before to 2.66 +/- 0.38 mm and 15 +/- 7% after the procedure in vessels with an average reference diameter of 3.05 +/- 0.35 mm. There were 3% of stent-related immediate clinical complications. In February 1996, 97 patients had survived 6 months. With a 97% follow-up rate, the clinical event rate was 18%. The angiographic follow-up rate was 70% and the restenosis rate was 27%. The authors conclude that the AVE microstents are easy to implant and provide excellent immediate angiographic results with a low complication rate

Intracoronary Stenting for Restenosis: Long-Term Follow-up: A Single Center Experience.

One-hundred thirteen stents (78 Wallstents, 29 Palmaz-Schatz and 6 Wiktor) were implanted in 106 patients aged 63 +/- 5 years to treat a restenosis following previous angioplasty in a native coronary artery (86 cases) and in a venous graft (20 cases). Implantation was technically possible in all cases. The native vessels had a mean reference diameter of 3.3 +/- 0.3 mm and their mean minimal lumen diameter increased from 1.2 +/- 0.3 mm before angioplasty to 2.8 +/- 0.8 after stent implantation. The venous grafts mean reference diameter was 4.4 +/- 0.7 mm and their mean minimal lumen diameter increased from 1.3 +/- 0.4 mm before angioplasty to 4.0 +/- 0.7 mm after implantation. Percentage stenosis in the native arteries and in the venous grafts were respectively 78 +/- 13% and 69 +/- 14% before angioplasty and 24 +/- 8% and 22 +/- 8% after stent implantation. Complications at 6 months, presented as a ranking scale with 100% follow-up rate were, overall, of 20% clinical events (4% deaths, 6% myocardial infractions, 2% coronary artery bypass grafting and 8% re-angioplasty). Angiographic complications were of 8% subacute thrombosis and 19% restenosis and chronic occlusions. Long-term, at 65 +/- 9 months, clinical (86% follow-up) and angiographic (74% follow-up) showed that only a further 9% clinical events and 14% restenosis (12% of them between 6 and 12 months) occurred after 6 months. At an estimated follow-up time of 104 months, 70% patients remain event-free and the survival rate is 95%. In conclusion, stent implantation in the treatment of restenosis following conventional balloon angioplasty is a valid strategy with good long-term results