Initial and Follow-up Results of Freedom (TM) Stent

Abstract

Background:The Freedom TM stent, which is one of recently developed balloon-expandable coil stents, has advantages of low profile and good trackability and flexibility. We evaluated the initial results and the late restenosis rate of Freedom TM stent in patients with coronary artery disease. Method:A total of 40 Freedom stents were implanted in 32 consecutive patients (38 lesions). The clinical diagnosis of the subjects were stable angina in 1 patient, unstable angina in 19, and acute myocardial infarction in 12. The indications of stenting were primary stenting in 11 stents, suboptimal result after PTCA in 26, and bailout procedure in 1. A mean diameter of reference artery was 3.1 mm (SD, ±0.4)and mean of lesion length was 10.9 mm (SD, ± 5.6). Stents were implanted with a mean maximal balloon pressure of 12.1 atm (SD, ±2.2). Follow-up angiography was done at least 3 months (mean duration, 8.7±3.7) after stenting for 28 lesions of 22 patients. Results:All 40 stents were implanted safely except one, which was complicated with side branch occlusion. There was no case of stent thrombosis and clinical success rate was 97% (31/32). Minimal luminal diameter (MLD) was increased from 0.7 (SD, ±0.4) to 3.0 mm (SD, ±0.4) and % of diameter stenosis (%DS) was decreased from 78 (SD, ±13)to 2% (SD, ±5) immediately after stenting. The overall restenosis rate was 28% (8/28). The restenosis rate was increased in the complex lesions (complex, 38% vs simple, 0%;p= 0.05) and lesion of small vessel (<3.0 mm, 50% vs ≥3.0 mm, 20%;p=0.11). Conclusion:Freedom TM stent is safe and feasible in patients with various morphology of coronary lesions including small and tortuous arteries, and in lesion associated with side branches. But lesions of small vessel and complex morphology are tend to be associated with higher rates of restenosis. (Korean Circulation J 1998;28(6):894-901)