Patient-level outcomes of patients undergoing resorbable magnesium scaffold (RMS) implantation stratified according to different subgroups: a post-hoc analysis of SHERPA MAGIC study
Authors: Pompei G , Campo G , Ruggiero R , Maffeo D , Sgura F , Preti G , Iannaccone M , Erriquez A , Biscaglia S , Sganzerla P , Capecchi A , Pignatelli G , Dall'ara G , Varbella F , Cerrato E 
Published: November 2023

Abstract

Background
The SHERPA-MAGIC is an investigator-driven, multicenter, prospective, single-arm study that enrolled patients undergoing resorbable magnesium scaffold (RMS) implantation in 18 Italian centers. The results from the first 543 patients supported the safety and long-term performance of RMS in a real-world population.

Purpose
The present post-hoc analysis aimed to assess differences in adverse events at patient-level (patient-oriented composite endpoints, POCE, defined as the composite of all-cause death, myocardial infarction -MI- and ischemia-driven coronary revascularization) at the longest follow-up between different subgroups of the final study population (n=543).

Methods
We identified the subgroups according to different variables: age, sex, cardiovascular risk factors, clinical presentation, left ventricle ejection fraction, multivessel disease, multivessel PCI, and antiplatelet therapy. If the analysis highlighted a subgroup of patients at higher risk of adverse events, to understand if this finding is related to RMS implantation or to the characteristic itself, a propensity score matched analysis was conducted comparing patients of the SHERPA-MAGIC study with a matched cohort of patients receiving second generation drug eluting stent. The endpoint for the comparison between the two matched cohorts was POCE.

Results
The mean age of the final study population was 56±9 years. 433 (78%) patients were men, and the most common clinical presentation was MI (n=402, 74%). At the median follow-up of 3.5 [2.6-4.3] years, the cumulative occurrence of the primary endpoint (vessel-oriented composite endpoints, VOCE, including cardiac death, target vessel MI, and ischemia-driven target vessel revascularization) was 37 (5.8%, 95%CI 4.1%-7.9%) and 54 (9.9%, 95% CI 7.5%-12.7%) patients met criteria for POCE. There was no significant difference among POCE in the subgroup analysis (Figure 1), with the exception of patients with MI as clinical presentation. As compared to patients admitted for chronic coronary syndrome, MI patients showed a significantly higher POCE rate (11.4 vs 5.6%, CI 8.5-14.9, p=0.04). Therefore, a propensity score matched analysis was conducted comparing MI patients of the SHERPA-MAGIC study with a matched cohort of MI patients from the Acute coRonary sYndrOmes proSpective regisTry Of Ferrara (ARYOSTO) study (NCT02438085) treated with second-generation DES. We did not find significant differences in the cumulative occurrence of POCE between SHERPA MAGIC and ARYOSTO (11.4% vs. 12.5% respectively, p=0.71) (Figure 2).

Conclusions
The present analysis confirmed the safety and effectiveness of RMS across several subgroups of patients stratified by clinical and procedural characteristics. We found that MI patients had an higher occurrence of POCE, but this was not related to RMS implantation. Indeed, a similar MI population treated with second generation DES showed the same long-term outcome.Fig 1POCE difference between subgroupsFig 2Propensity matched MI populations