Primary Stenting in Acute MI
ABSTRACT & COMMENTARY
Synopsis: In selected MI patients, primary stenting achieves reduced recurrent MI and target vessel revascularization rates as compared to balloon angioplasty.
Source: Suryapranata H, et al. Circulation 1998;97: 2502-2505.
The value of primary angioplasty in acute myocardial infarction (MI) has been demonstrated, but early re-occlusion and late restenosis remain disappointingly high. Since coronary stents may abrogate these problems, a prospective, randomized trial comparing stenting to plain old balloon angioplasty (POBA) was conducted by Suryapranata and associates. They randomized 227 patients with acute MI and a culprit lesion suitable for stenting to POBA vs. stent placement. The primary end points were death, recurrent MI, subsequent coronary artery bypass grafting (CABG), or repeat angioplasty. Early reocclusion occurred in five POBA patients and one stent patient; repeat angioplasty or CABG (stent patient) was performed in all. At six months, there were only five deaths (2%). Recurrent MI was more common after POBA than stenting (8 vs 1 patient; P = 0.036). Subsequently, target vessel revascularization was necessary in 19 POBA patients and four stent patients (P < 0.002). The cardiac event-free survival rate was significantly higher in the stent group vs. the POBA group (95 vs 80%; P < 0.02). Suryapranata et al conclude that in selected MI patients, primary stenting achieves reduced recurrent MI and target vessel revascularization rates as compared to balloon angioplasty.
COMMENT BY MICHAEL H. CRAWFORD, MD
The major fears concerning the use of stents in primary angioplasty of acute MI patients were initial success and complications. These fears are allayed by this study. In fact, there were fewer early re-occlusions in the stent group, attesting to its safety. The second concern was the applicability of stenting to most acute MI patients given the anatomical constraints of stent placement. This concern is justified based upon the results of this study because about half of the patients who were candidates for primary angioplasty were not suitable for stent placement. Most were excluded for an infarct-related vessel that was too small (34%). Diffuse infarct vessel scarring excluded another 21%, and significant side branch concerns eliminated 11%. Extensive thrombosis or no-reflow excluded 8%. Thus, the applicability of stenting to acute MI patients is unclear. For this reason, Suryapranata et al are conducting another trial in which patients are randomized before angioplasty. Finally, this study was done at a high-volume center, so the transferability of the results to other hospitals is not known. However, the study does suggest that, in experienced hands, selected patients undergoing primary angioplasty for acute MI can benefit from stent placement and that this approach is safe.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content