COMPARISON OF RESULTS OF INTRACORONARY STENTING IN PATIENTS WITH UNSTABLE VS STABLE ANGINA

Percutaneous transluminal coronary angioplasty (PTCA) has higher complication and restenosis rates when performed in the setting of unstable angina. Balloon-expandable intracoronary stenting is a new technique with the potential to improve the results of PTCA. In order to determine whether stenting is associated with a poorer outcome in patients with unstable angina, we retrospectively examined our experience with the Palmaz-Schatz balloon-expandable intracoronary stent in 105 patients. Patients were divided into 2 groups on the basis of symptoms at the time of stent insertion: group I (n = 57) had stable angina pectoris, and group II (n = 48) had unstable angina defined as pain at rest despite antianginal therapy (Braunwald class II, III). Initial (30-d) and final (6-mo) success rates were defined as stent insertion without myocardial infarction, need for bypass surgery, death, and significant angina. Baseline characteristics were similar, although the patients with unstable symptoms were older, more likely to be female, and had a higher incidence of postinfarction angina. A total of 136 stents were successfully delivered to 97 target sites in 92% of patients. Major complications occurred in 4 patients (4%) and were due to subacute thrombosis in 3 of them. There were no differences in complication rates between patients receiving stents electively with stable vs. unstable symptoms (2% vs. 6%, p = NS). Six-mo. follow-up status was ascertained in 96% of patients and revealed overall clinical success in 83% with angiographic restenosis (greater than or equal to 50% stenosis) in 28% of patients. There were no significant differences between groups in rates of restenosis, follow-up angina class, or overall clinical success. Patients with unstable angina receiving intracoronary stents have similar complication, restenosis, and initial and final success rates as compared to stent placement in patients with stable symptoms. This finding differs from previous observations of conventional PTCA and may result from mechanical improvements in the vessel due to the stent (e.g., sealing intimal dissections) or the associated anticoagulation regimen. (C) 1994 Wiley-Liss, Inc.