Drug-eluting stents compared to bare-metal stents improve mortality in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention - A Nationwide Prospective Analysis of AMIS

Abstract

BACKGROUND: Recently, it has been suggested that the type of stent used in primary percutaneous coronary interventions (pPCI) might impact on outcomes of patients with acute myocardial infarction (AMI). Indeed, drug-eluting stents (DES) reduce neointimal hyperplasia when compared to bare-metal stents (BMS); moreover the later generation DES due to its biocompatible polymer coatings and stent design allow for greater deliverability, improved endothelial healing and therefore less restenosis rate and thrombus generation. However, data on the safety and performance of DES in large cohorts of AMI are still limited.
AIM: To compare the early outcome of DES vs. BMS in acute myocardial infarction patients.
METHODS: This was a prospective, multicenter analysis containing patients from 64 hospitals in Switzerland with AMI undergoing pPCI between 2005 and 2013. The primary endpoint was in-hospital all-cause death, whereas the secondary endpoint included a composite measure of major adverse cardiac and cerebrovascular events (MACCE) of death, reinfarction, and cerebrovascular event.
RESULTS: Of 20 464 patients with the primary diagnosis of AMI and enrolled to the AMIS Plus Registry, 15 026 were referred for pPCI and 13 442 received stent implantation. 10 094 patients were implanted with DES and 2 260 with BMS. The overall in-hospital mortality was significantly lower in patients with DES as compared to those with BMS implantation (2.6% vs. 7.1%, p<0.001). The overall in-hospital MACCE after DES was similarly lower when compared with BMS (3.5% vs. 7.6%; p<0.001). After adjusting for all confounding covariables, the DES remained an independent predictor for lower in-hospital mortality (odds ratio [OR], 0.51;95% confidence interval [CI], 0.40 to0.67; p<0.001). Since groups differed as regards baseline characteristics and pharmacological treatment we performed a propensity score matching (PSM) to limit potential biases. Similarly, after the PSM, DES implantation remained independently associated with reduced risk of in-hospital mortality (adjusted odds ratio [aOR], 0.54; 95% confidence interval [CI], 0.39 to 0.76; p<0.001). Conclusion: In unselected patients from a nationwide, real-world cohort, we found DES as compared to BMS was associated with lower in-hospital mortality and MACCE. The identification of optimal treatment strategies of patients with AMI needs further randomized evaluation; however, our findings suggest potential benefit with DES.