Stenting improved combined but not individual outcomes after PTCA
ACP J Club. 1998 Nov-Dec; 129:64. doi:10.7326/ACPJC-1998-129-3-064
Antoniucci D, Santoro GM, Bolognese L, et al. A clinical trial comparing primary stenting of the infarct-related artery with optimal primary angioplasty for acute myocardial infarction. Results from the Florence Randomized Elective Stenting in Acute Coronary Occlusions (FRESCO) trial. J Am Coll Cardiol. 1998 May;31:1234-9.
Does stenting of the infarction-related artery (IRA) after primary percutaneous transluminal coronary angioplasty (PTCA) improve clinical or angiographic outcomes for patients with acute myocardial infarction (MI)?
Randomized controlled trial.
A hospital in Florence, Italy.
150 adults (mean age 62 y, 78% men) who had chest pain for > 30 minutes associated with ST-segment elevation ≥ 0.1 mV in ≥ 2 contiguous electrocardiographic leads and presented within 6 hours of symptom onset or within 6 to 24 hours of symptom onset if ischemia was ongoing. Exclusion criteria were previous fibrinolytic therapy, stenosis of the IRA < 70%, inability to identify the IRA, and vessel diameter < 2.5 mm.
All patients received primary PTCA; intravenous heparin for 3 days; aspirin, 325 mg/d, indefinitely; and ticlopidine, 500 mg/d, for 2 months. After PTCA, 75 patients were allocated to primary stenting of the IRA with the Gianturco-Roubin coronary stent implanted using standard, high-pressure techniques. The other 75 patients received no primary stent.
Main outcome measures
A composite end point of death, reinfarction, or repeated target vessel revascularization because of recurrent ischemia within 6 months. The secondary outcome was angiographic evidence of restenosis ≥ 50% or reocclusion.
Analysis was by intention to treat. By 6 months, fewer patients in the stent group than in the PTCA-only group had an outcome event (7 vs 21 events, P = 0.003) (Table), although the groups did not differ for death (0 vs 1, P > 0.2) or reinfarction (2 vs 1, P > 0.2). Most deaths and reinfarctions occurred within 30 days. Kaplan-Meier curves showed that 87% of patients with stents compared with 68% of the PTCA-only group were free of the composite end point at 6 months (P = 0.002). Angiographic data favored the stent group for early (< 30 d), late (31 to 180 d), and overall restenosis or reocclusion (P ≤ 0.04 for all comparisons).
Primary stenting of the infarction-related artery after PTCA reduced the combined end point of death, reinfarction, or revascularization, although the groups did not differ foreither death or reinfarction alone.
Source of funding: Not stated.
For correspondence: Dr. D. Antoniucci, Division of Cardiology, Careggi Hospital, Viale Morgagni, I-50134, Florence, Italy. FAX 39-55-4277625.
Table. Stenting after percutaneous transluminal coronary angioplasty (PTCA) vs PTCA alone for acute myocardial infarction*
|Outcomes at 6 mo||Stenting||PTCA||RRR (95% CI)||NNT (CI)|
|Death, reinfarction, or revascularization||9%||28%||66.7% (28.8 to 84.8)||5 (3 to 15)|
|Restenosis or occlusion||17%||43%||60.3% (29.9 to 78.0)||4 (3 to 10)|
*Abbreviations defined in Glossary; RRR, NNT, and CI calculated from data in article.
Finding the optimal reperfusion strategy for acute ST-segment elevation in acute MI is challenging because the target is moving, and at lightning speed. Investigators are exploring the role of direct PTCA; direct PTCA with stenting (primary stenting);various thrombin inhibitors; and novel anti-platelet agents, particularly the glycoprotein IIb/IIIa inhibitors. Results of studies that test these interventions are guardedly encouraging.
Should we embrace all or some of these results? Readers should keep the following in mind: In the setting of acute MI, thrombolysis can be recommended for eligible patients on the basis of randomized trials involving > 55 000 patients, β-blocker trials involving > 25 000 patients, and angiotensin-converting enzyme inhibitor trials involving > 120 000 patients. In contrast, direct PTCA has been tested in only 2600 patients and primary stenting in only 150. Although the results of this important study are encouraging and are supported by the results of the PAMI Stent Pilot Trial, they must be considered to be preliminary (1). Further, the differences between PTCA and stenting were in rates of target-vessel revascularization and not in death or recurrent acute MI. The trial was too small to discern differences in death or MI, and protocol-mandated angiography may have driven the choice of revascularization as an outcome.
With or without stenting, PTCA may indeed be feasible and safe in acute MI. Worldwide, most patients with acute MI will not have ready access to the technology andresources or to personnel experienced in the delivery of these services. To date, PTCA has not been proved to be conclusively better than thrombolysis, which, at least for now, remains the reperfusion strategy of choice for most patients. Time will tell which is better—thrombolysis and adjunctive novel antithrombotic therapy or catheter-based reperfusion.
David Massel, MD
London Health Sciences Centre, Victoria CampusLondon, Ontario, Canada
1. Stone GW, Brodie BR, Griffin JJ, et al. Prospective, multicenter study of the safety and feasibility of primary stenting in acute myocardial infarction: in-hospital and 30-day results of PAMI stent pilot trial. Primary Angioplasty in Myocardial Infarction Stent Pilot Trial Investigators. J Am Coll Cardiol. 1998;31:23-30.