Background: The MGuard (MG) is a stainless-steel closed cell stent covered with an ultra-thin polymer mesh sleeve, which has the purpose of ensuring reduced distal embolization of thrombotic material, thus lowering the risk of no-reflow/slow-flow phenomena. Only few data are available that evaluated the usefulness of the MG stent in patients with ST-elevation myocardial infarction (STEMI) with a high thrombotic burden.
Methods: We prospectively collected data of patients presenting with STEMI and high thrombotic burden (thrombus burden grade 4 or 5 according to the TIMI score) who underwent primary percutaneous coronary intervention (PCI) with MG stent implantation in our center. Lesions involving a bifurcation or very calcified and tortuous vessels were not included. Final TIMI 3 flow, normal myocardial blush grade (MBG), and complete ST-segment resolution were defined as short-term endpoints, whereas major adverse cardiovascular events were evaluated during follow-up.
Results: From August 2008 to June 2013, the MG stent was implanted in 104 (9.3%) of 1108 patients who underwent primary PCI. Cardiogenic shock on admission was present in 4 patients (3.8%). Final TIMI 3 flow was achieved in 97.1% of patients, MBG 3 in 56.7%, and regression of ST-segment elevation ≥70% within 90 min was recorded in 64.4% of patients. In-hospital mortality was 2.9% (n=3), and at a mean follow-up of 455±430 days overall major adverse cardiovascular events were 11 (10.6%). Cardiac death occurred in 5 patients (4.9%) and stent thrombosis in 2 (1.9%).
Conclusions: In selected patients with STEMI undergoing primary PCI, the use of the mesh-covered MG stent in vessels with high thrombotic burden despite thrombus aspiration was effective and safe both immediately and at mid-term follow-up.