Is Unstable Angina a Contraindication to Intracoronary Stent Insertion?

BACKGROUND: Percutaneous transluminal coronary angioplasty is associated with higher rates of acute complications and restenosis when performed in the clinical setting of unstable angina. Coronary stent insertion has been shown to reduce restenosis when performed electively. The effect of unstable angina on clinical outcome after stent deployment is currently unclear. OBJECTIVE: To compare the clinical outcome after coronary stents inserted in patients with unstable and stable angina. DESIGN: A retrospective analysis of all patients receiving Palmaz-Schatz stents electively or for sub-optimal angioplasty result in patients with stable and unstable angina. PATIENTS: One-hundred fifty-seven patients received 178 Palmaz-Schatz stents electively or for the treatment of sub-optimal result. Thrombolysis in Myocardial Infarction Study (TIMI) grade 3 flow was present in all patients at the time of stent delivery. Unstable angina was defined as pain at rest despite anti-anginal therapy (Braunwald class II, III). Eighty-three patients (mean age 58 years) with unstable angina received 95 stents and 74 patients (mean age 57 years) with stable angina received 83 stents. MAIN OUTCOME MEASURES: Subacute stent thrombosis (SAST), myocardial infarction (MI), need for repeat angiography, coronary bypass graft surgery (CABG) and death. RESULTS: The early complications (within 2 weeks) comparing the unstable and stable groups respectively were: No deaths, SAST 3/83 (3.6%) vs. 2/74 (2.7%), MI 2/83 (2.4%) vs. 2/74 (2.7%) and CABG 6/83 (7.2%) vs. 2/74 (2.7%). After 2 weeks no patient had a MI or CABG. Clinical follow-up was continued up to 6 months. Two patients in each group had repeat angiography for recurrent symptoms. One patient in the stable group died from non-cardiac causes. CONCLUSIONS: There appears to be no difference in the early or late clinical outcome of patients with unstable or stable angina treated with coronary stent insertion when TIMI flow is normal at the time of stent insertion.