Six Months' Clinical and Angiographic Follow-up of a Flexible, Coiled Stainless Steel Stent in Long, Native Coronary Artery Lesions

Abstract

This study was conducted to evaluate the short- and long-term clinical and angiographic results of implantation of a flexible, coiled stainless steel stent, the Freedom Coronary Stent. During the study period this stent was used as an alternative to the Palmaz-Schatz PS153 coronary stent in long or tortuous lesions. The study was designed as a prospectively planned outcome analysis. Implantation of Freedom stents was attempted in 62 consecutive patients (56% males, mean age 63+/-10 years) with a total of 65 coronary lesions. Indications for stent implantation were: restenosis, 8%; recoil, 26%; visible dissection, 32%; threatening occlusion, 15%; chronic total occlusion, 18%. The average stent length was 30+/-16 mm and 67% of the lesions were type C. Rate of successful stent implantation, acute complications, angiographic restenosis after 6 months and major cardiac events (death, myocardial infarction, target vessel revascularization) during follow-up were assessed. The success rate of stent implantation was 94%. One patient died after an emergency bypass operation and one patient suffered a subacute stent thrombosis, which was successfully treated with re-percutaneous transluminal coronary angioplasty (PTCA). There were no Q- or non-Q myocardial infarctions. Clinical follow-up was carried out in 56 patients (97%) and 57 vessels were assessed by angiography (93%). Mean length of the follow-up period was 6.8+/-2.3 months. During the 6 months' follow-up period, one patient died, two patients suffered an acute non-Q myocardial infarction and eight patients had revascularization of the target vessel. Major cardiac event rate for all patients where stent implantation was intended was 23%. Angina CCS class declined from 3.0+/-0.9 to 1.1+/-0.8 (p < 0.01) before PTCA to follow-up. Overall restenosis rate was 28%. In 14 lesions with a stented segment length of <20 mm, the restenosis rate was 21%; in 31 lesions with a stented segment length > or =20 and <30 mm, the restenosis rate was 26%; and in 13 lesions with a stented segment length of > or =30 mm, the restenosis rate was 42%. Although there was a high procedural success rate after implantation of the Freedom stent in long or tortuous lesions, problems with high restenosis rates in long lesions remain unresolved.