Long-term risk of clinical events from stenting side branches of coronary bifurcation lesions with drug-eluting and bare-metal stents: an observational meta-analysis.

Objectives: To compare the long-term risks of coronary bifurcation lesions treated with side-branch stenting using drug-eluting versus bare-metal stents.
Background: Side-branch stenting is an off-label practice, but when needed, the incidence of late adverse events may differ between drug-eluting and bare-metal stents.
Methods: We systematically searched PubMed, and the National Institutes of Health and Cochrane Registries for studies of coronary bifurcation stenting reporting clinical outcomes over at least 5 months. Data were extracted and cross checked independently by two investigators for inclusion in an observational meta-analysis. Clinical outcomes included major adverse clinical events (MACE), death, myocardial infarction, target vessel revascularization (TVR), and definite stent thrombosis. We used random-effects models and meta-regression in 6,825 subjects from 42 studies.
Results: Most (79%) of the heterogeneity in MACE between treatment groups was explained by differences in stent type, side-branch stenting, and length of follow-up. Compared with drug-eluting stents without side-branch stenting, drug-eluting stents with side-branch stenting had a 3% higher incidence of myocardial infarction [95% confidence interval (CI) = 0.3%, 5%, P < 0.05], but no significant increase in MACE, death, TVR, or stent thrombosis. Bare-metal stenting without side-branch stenting had 10% (95% CI = 3%, 16%, P < 0.01) higher MACE, and 10% (95% CI = 4%, 17%, P < 0.01) higher TVR, whereas bare-metal side-branch stenting had 31% (95% CI = 23%, 39%, P < 0.001) higher MACE, and 19% (95% CI = 10%, 28%, P < 0.001) higher TVR.
Conclusions: Side-branch stenting has a much smaller impact on long-term MACE with drug-eluting stents compared with bare-metal stents. Although this study does not support routine side-branch stenting, when side-branch stenting is required, drug-eluting stents are associated with less adverse outcomes.
(Copyright © 2011 Wiley-Liss, Inc.)