Coronary stenting for unstable angina: predictors of 30-day and long-term clinical outcome

Background Unstable angina is usually caused by acute thrombosis superimpos ed on a fissured plaque. Coronary artery stenting has been shown to improve short- and long-term results of coronary angioplasty in mainly stable pati ents with one-vessel disease, but it is uncertain whether its use in an uns table clinical setting can be safe and useful. This study sought to evaluat e the results of coronary stenting in unstable angina and to determine pati ent, lesion and procedure-related predictors of 30-day and long-term ischem ic events. Methods We studied 266 consecutive patients (mean age 62+/-9 years) with un stable angina who underwent coronary artery stenting. The procedure was per formed electively in 24%, in bailout situations in 11% and for a suboptimal result of conventional angioplasty in 65%, After stent implantation, patie nts were treated with anticoagulation (61) or combined antiplatelet therapy (200). Multivariate logistic regression analyses were performed to determi ne 30-day and long-term predictive factors of ischemic complications. Results Procedural success was obtained in 261 patients (98.1%). During the first 30 days after stenting, one patient died from cardiogenic shock (0.3 %) and six (2.2%) suffered a non-fatal Q-wave myocardial infarction. Patien ts with combined antiplatelet therapy had a significantly lower stent throm bosis rate (1.5% versus 11.4%, P = 0.002) than those treated with anticoagu lant regimen, At long-term follow-up (17.7 +/- 9.4 months) cardiac mortalit y, myocardial infarction and target-vessel revascularization rates were 0.4 %, 1.5% and 9.3%, respectively. In multivessel and diabetic patients, a wor se long-term event-free survival was observed. Logistic multivariate analys is revealed bailout stenting, anticoagulant therapy, implantation of stents longer than 15 mm as predictors of 30-day ischemic events. In addition, mu ltivessel coronary artery disease and stent application with balloon size o f less than 3 mm were predictive of long-term ischemic events. Conclusions This study demonstrates that, either electively or after failur e of conventional angioplasty, coronary stenting represents an effective th erapy for patients with unstable angina, In the same clinical setting, comb ined antiplatelet therapy is associated with a lower 30-day stent thrombosi s rate than anticoagulant therapy. Bailout stenting, anticoagulant therapy, implantation of stents longer than 15 mm were shown to be predictors of 30 -day ischemic events, whereas multivessel coronary artery disease and stent application with small balloon size were predictive of long-term ischemic events, Coronary Artery Dis 10:81-88 (C) 1999 Lippincott Williams & Wilkins .