A Randomized Trial of Deferred Stenting Versus Immediate Stenting to Prevent No- or Slow-Reflow in Acute ST-Segment Elevation Myocardial Infarction (DEFER-STEMI)

Abstract

ObjectivesThe aim of this study was to assess whether deferred stenting might reduce no-reflow and salvage myocardium in primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI).BackgroundNo-reflow is associated with adverse outcomes in STEMI.MethodsThis was a prospective, single-center, randomized, controlled, proof-of-concept trial in reperfused STEMI patients with ≥1 risk factors for no-reflow. Randomization was to deferred stenting with an intention-to-stent 4 to 16 h later or conventional treatment with immediate stenting. The primary outcome was the incidence of no-/slow-reflow (Thrombolysis In Myocardial Infarction ≤2). Cardiac magnetic resonance imaging was performed 2 days and 6 months after myocardial infarction. Myocardial salvage was the final infarct size indexed to the initial area at risk.ResultsOf 411 STEMI patients (March 11, 2012 to November 21, 2012), 101 patients (mean age, 60 years; 69% male) were randomized (52 to the deferred stenting group, 49 to the immediate stenting). The median (interquartile range [IQR]) time to the second procedure in the deferred stenting group was 9 h (IQR: 6 to 12 h). Fewer patients in the deferred stenting group had no-/slow-reflow (14 [29%] vs. 3 [6%]; p = 0.006), no reflow (7 [14%] vs. 1 [2%]; p = 0.052) and intraprocedural thrombotic events (16 [33%] vs. 5 [10%]; p = 0.010). Thrombolysis In Myocardial Infarction coronary flow grades at the end of PCI were higher in the deferred stenting group (p = 0.018). Recurrent STEMI occurred in 2 patients in the deferred stenting group before the second procedure. Myocardial salvage index at 6 months was greater in the deferred stenting group (68 [IQR: 54% to 82%] vs. 56 [IQR: 31% to 72%]; p = 0.031].ConclusionsIn high-risk STEMI patients, deferred stenting in primary PCI reduced no-reflow and increased myocardial salvage. (Deferred Stent Trial in STEMI; NCT01717573)

ST elevation myocardial infarction

“…STEMI accounted for 39% (31,653 patients) of all hospital admissions due to myocardial infarction in the UK (excluding Scotland). 1 The unadjusted 30-day mortality rate for STEMI patients was 8.1% during the period 2013-14, compared with ABSTRACT ST elevation myocardial infarction 12.4% ten years earlier (2003)(2004));…”

“…Other avenues showing early promise in STEMI include deferred compared with immediate stenting following reestablishment of flow in the culprit artery, 31 use of systemic hypothermia (COOL AMI pilot trial), 32 bone marrow-derived cell therapy (BAMI trial) 33 and ischaemic preconditioning. …”

Comparison of Immediate With Delayed Stenting Using the Minimalist Immediate Mechanical Intervention Approach in Acute ST-Segment–Elevation Myocardial Infarction

“…7,9,10 A singlecenter proof-of-concept study reported a lower rate of angiographic no-reflow in patients treated with DS versus IS, but the population was limited to individuals with a high risk of no-reflow. 11 The MIMI trial was conducted to confirm whether delayed (24-48 hours) versus immediate stent implantation significantly reduced myocardial MVO as determined by cardiac magnetic resonance imaging (MRI), thus improving myocardial reperfusion in patients with acute STEMI undergoing primary PCI.…”

Management of Intracoronary Thrombus

“…All patients should proceed urgently to the catheterization laboratory, and flow may need to be restored with a wire or gentle predilatation with a balloon. If high burden of thrombus is seen, deferred stenting with an interim period of adjunctive antiplatelet/anti thrombotic therapy may be useful to reduce the thrombus load and minimize complications (such as no-reflow) at time of stenting [47,48].…”