Elective Stenting versus Balloon Angioplasty with Bail-out Stenting for Small Vessel Coronary Artery Disease: Evidence from a Meta-analysis of Randomized Trials TCT, Washington, 30 September 2004

There are no conflicts of interest nor funding to declare Pierfrancesco Agostoni on behalf of all co-authors

INTRODUCTION Bare-metal stents have been shown to reduce angiographic restenosis and repeat revascularization in discrete lesions in large vessels. 1,2 1.Serruys PW, et al. BENESTENT Trial. NEJM, Fishman DL, et al. STRESS Trial. NEJM,1994 The use of stents has increased radically also for “non-STRESS/BENESTENT” lesions, despite the lack of evidence of benefit.

INTRODUCTION Small vessels (with RVD < 3 mm) account for 40-50% of all coronary stenoses Wong P, et al. Catheter Cardiovasc Interv, 2000 Several recent randomized trials have compared bare-metal stenting vs. PTCA in small vessels, with conflicting and overall inconclusive results.

INTRODUCTION As systematic overviews and meta-analytic techniques may provide more precise effect estimates with greater statistical power, leading to more robust and generalized conclusions...

AIM OF OUR REVIEW *Research *Retrieve *Evaluate *Combine in a systematic way all the randomized trials comparing bare-metal stenting vs. PTCA for the treatment of atherosclerotic lesions in small coronary vessels.

METHODS Systematic Research MEDLINE, CENTRAL AHA, ACC, ESC, TCT abstracts Inclusion criteria Prospective comparison Randomized allocation Intention-to-treat Follow-up  6 months Exclusion criteria Non-mandatory angiographic follow-up Use of DES or other devices  stents Antithrombotic drugs  ASA and thienopyridines

METHODS Death Myocardial infarction Repeat revascularization (TVR/TLR) MACE Secondary end-points Restenosis, RVD, MLD pre-, post-PCI and at follow-up, DS pre-, post-PCI and at follow-up, acute gain, late loss Primary End-points

METHODS Binary outcomes Odds Ratios (95% Confidence Intervals) Random effect model Heterogeneity Cochran Q  2 test

METHODS Trials with mean DS post-PTCA < 20% (optimal) and Trials with mean DS post-PTCA > 20% (sub-optimal) 1. ACC Expert consensus Document JACC, Kastrati et al. JACC, 2001 Pre-specified sub-group analysis 1,2

Included Studies

Death Heterogeneity: p = 0.76 Overall effect: p = 0.42

Myocardial Infarction Heterogeneity: p = 0.92 Overall effect: p = 0.18

Repeat Revascularization Heterogeneity: p = 0.04 Overall effect: p = 0.02 Heterogeneity: p = 0.62 Overall effect: p = 0.54

MACE Heterogeneity: p = 0.01 Overall effect: p = Heterogeneity: p = 0.27 Overall effect: p = 0.24

CONCLUSIONS Bare-metal stenting is clinically superior to PTCA for the treatment of small vessels, in particular when compared to a sub-optimal PTCA result. The finding of significant heterogeneity casts a light of caution on the comprehensive pooled effect estimates. A strategy based on “optimal” PTCA with provisional stenting may be a valid alternative to systematic stenting.

CONCLUSIONS In any case, the rates of MACE (17%) and repeat revascularization (15%) remain high after stenting, unfavorably comparing with the MACE and revascularization rates in vessels with RVD > 3 mm (  10%). 4,5 4. Weaver WD, et al. OPUS-1 Trial. Lancet, Serruys PW, et al. JACC, 1999

Future Strategies As drug-eluting stents have been proved to be effective both in randomized trials 6-8 and in observational registries 8 … 6. Schofer J, et al. E-SIRIUS Trial. Lancet, Schampaert E, et al. C-SIRIUS Trial. JACC, Ardissino D. SES-SMART Trial. ACC meeting, Lemos PA, et al. RESEARCH Registry. AJC, 2004 The use of DES should be considered the first-line therapy for the treatment of vessels with RVD < 3 mm.

Angiographic Restenosis Heterogeneity: p = Overall effect: p < Heterogeneity: p = 0.11 Overall effect: p = 0.25

High quality trials: Park et al., ISAR-SMART, SISCA

Quality Assessment Jadad’s Score (0-5 points) Study defined as randomized (1 point) –if randomization was correct 1 point more –if not correct 1 point less –if not mentioned no points Study defined as blinded (1 point) –it is impossible in “interventional” trials! Stent is visible! Clear description of drop-outs and withdrawals (1 point)

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