Routine thrombectomy in percutaneous coronary intervention for acute ST-segment-elevation myocardial infarction: a randomized, controlled trial

Impact of thrombus aspiration on left ventricular remodeling and function in patients with ST-segment elevation myocardial infarction: A meta-analysis of randomized controlled trials

BACKGROUND

Routine thrombus aspiration (TA) does not improve clinical outcomes in patients with ST-segment-elevation myocardial infarction (STEMI), although data from meta-analyses suggest that patients with high thrombus burden may benefit from it. The impact of TA on left ventricular (LV) functional recovery and remodeling after STEMI remains controversial. We aimed to pool data from randomized controlled trials (RCTs) on the impact of TA on LV function and remodeling after primary percutaneous coronary intervention (pPCI).

METHODS

PubMed and CENTRAL databases were scanned for eligible studies. Primary outcome measures were: LV ejection fraction (LVEF), LV end diastolic volume (LVEDV), LV end systolic volume (LVESV) and wall motion score index (WMSI). A primary pre-specified subgroup analysis was performed comparing manual TA with mechanical TA.

RESULTS

A total of 28 studies enrolling 4990 patients were included. WMSI was lower in TA group than in control (mean difference [MD] -0.11, 95% confidence interval [CI] -0.19 to -0.03). A greater LVEF (MD 1.91, 95% CI 0.76 to 3) and a smaller LVESV (MD -6.19, 95% CI -8.7 to -3.6) were observed in manual TA group compared to control. Meta regressions including patients with left anterior descending artery (LAD) involvement showed an association between TA use and the reduction of both LVEDV and LVESV (z = -2.13, p = 0.03; z = -3.7, p < 0.01) and the improvement in myocardial salvage index (z = 2.04, p = 0.04).

CONCLUSION

TA is associated with improved LV function. TA technique, total ischemic time and LAD involvement appears to influence TA benefit on post-infarction LV remodeling.

Efficacy of thrombus aspiration in cardiogenic shock complicating acute myocardial infarction and high thrombus burden

INTRODUCTION AND OBJECTIVES

Current guidelines do not recommend routine thrombus aspiration in acute myocardial infarction (AMI) because no benefits were observed in previous randomized trials. However, there are limited data in cardiogenic shock (CS) complicating AMI.

METHODS

We included 575 patients with AMI complicated by CS. The participants were stratified into the TA and no-TA groups based on use of TA. The primary outcome was a composite of 6-month all-cause death or heart failure rehospitalization. The efficacy of TA was additionally assessed based on thrombus burden (grade I-IV vs V).

RESULTS

No significant difference was found in in-hospital death (28.9% vs 33.5%; P=.28), or 6-month death, or heart failure rehospitalization (32.4% vs 39.4%; HRadj: 0.80; 95%CI, 0.59-1.09; P=.16) between the TA and no-TA groups. However, in 368 patients with a higher thrombus burden (grade V), the TA group had a significantly lower risk of 6-month all-cause death or heart failure rehospitalization than the no-TA group (33.4% vs 46.3%; HRadj: 0.59; 95%CI, 0.41-0.85; P=.004), with significant interaction between thrombus burden and use of TA for primary outcome (adjusted Pint=.03).

CONCLUSIONS

Routine use of TA did not reduce short- and mid-term adverse clinical outcomes in patients with AMI complicated by CS. However, in select patients with a high thrombus burden, the use of TA might be associated with improved clinical outcomes. The study was registered at ClinicalTrials.gov (Identifier: NCT02985008).

Intracoronary pharmacological therapy versus aspiration thrombectomy in STEMI (IPAT-STEMI): A systematic review and meta-analysis of randomized trials

BACKGROUND

Thrombus load in STEMI patients remains a challenge in practice. It aggravates coronary obstruction leading to impaired myocardial perfusion, worsened cardiac function, and adverse clinical outcomes. Various strategies have been advocated to reduce thrombus burden.

OBJECTIVES

This meta-analysis aimed to evaluate the effectiveness of intracoronary-administered thrombolytics or glycoprotein IIb/IIIa inhibitors (GPI) in comparison with aspiration thrombectomy (AT) as an adjunct to percutaneous coronary intervention (PCI) among patients presenting with ST-segment elevation myocardial infarction (STEMI).

METHODS

A comprehensive literature search for randomized trials that compared intracoronary-administered thrombolytics or GPI with AT in STEMI patients who underwent PCI, was conducted using various databases (e.g., MEDLINE, EMBASE, CENTRALE). Primary outcome was procedural measures (e.g., TIMI flow grade 3, TIMI myocardial perfusion grade (TMPG) 3, Myocardial blush grade (MBG) 2/3, ST-segment resolution (STR)).

RESULTS

Twelve randomized trials enrolled 1,466 patients: 696 were randomized to intracoronary-administered pharmacological interventions and 553 to AT. Patients randomized to PCI alone were excluded. Thrombolytics significantly improved TIMI flow grade 3 (odds ratio = 3.71, 95% CI: 1.85-7.45), complete STR (odds ratio = 3.64, 95% CI: 1.60-8.26), and TMPG 3 (odds ratio = 5.31, 95% CI: 2.48-11.36). Thrombolytics significantly reduced major adverse cardiovascular events (MACE) (odds ratio = 0.29, 95% CI: 0.13-0.65) without increasing bleeding risk. Trial sequential analysis assessment confirmed the superiority of thrombolytics for the primary outcome. Intracoronary GPI, either alone or combined with AT, did not improve procedural or clinical outcomes.

CONCLUSIONS

Compared with AT, intracoronary-administered thrombolytics significantly improved myocardial perfusion and MACE in STEMI patients.

Remote Ischemic Conditioning in Ischemic Stroke and Myocardial Infarction: Similarities and Differences

Acute myocardial infarction and ischemic stroke are leading causes of morbidity and mortality worldwide. Although reperfusion therapies have greatly improved the outcomes of patients with these conditions, many patients die or are severely disabled despite complete reperfusion. It is therefore important to identify interventions that can prevent progression to ischemic necrosis and limit ischemia-reperfusion injury. A possible strategy is ischemic conditioning, which consists of inducing ischemia – either in the ischemic organ or in another body site [i.e., remote ischemic conditioning (RIC), e.g., by inflating a cuff around the patient's arm or leg]. The effects of ischemic conditioning have been studied, alone or in combination with revascularization techniques. Based on the timing (before, during, or after ischemia), RIC is classified as pre-, per-/peri-, or post-conditioning, respectively. In this review, we first highlight some pathophysiological and clinical similarities and differences between cardiac and cerebral ischemia. We report evidence that RIC reduces circulating biomarkers of myocardial necrosis, infarct size, and edema, although this effect appears not to translate into a better prognosis. We then review cutting-edge applications of RIC for the treatment of ischemic stroke. We also highlight that, although RIC is a safe procedure that can easily be implemented in hospital and pre-hospital settings, its efficacy in patients with ischemic stroke remains to be proven. We then discuss possible methodological issues of previous studies. We finish by highlighting some perspectives for future research, aimed at increasing the efficacy of ischemic conditioning for improving tissue protection and clinical outcomes, and stratifying myocardial infarction and brain ischemia patients to enhance treatment feasibility.

Stenting deferral in primary percutaneous coronary intervention: exploring benefits and suitable interval in heavy thrombus burden

BACKGROUND

Deferred stenting, despite being successful in early studies, showed no benefit in recent trials. However, these trials were testing routine deferral; not in patients with heavy thrombus burden.

RESULTS

This is a prospective, Randomized Clinical Trial that included 150 patients who presented with STEMI, patients were allocated into three equal groups after the coronary angiography ± primary intervention and before stenting of the culprit lesion; group (A) included 50 patients with early deferral of stenting, group (B) included 50 patients with late deferral and group (C) included 50 patients with immediate stenting. No-reflow was significantly higher in group C, while Final TIMI flow grade 3 and MBG grade 3 were significantly higher in group A and B than group C; p = 0.019 and < 0.001 respectively, with no significant difference between groups A and B, only the thrombus resolution in group B was significantly higher than group A; p < 0.001. Finally, 6-months, over-all MACE was significantly higher in group C (34.7% vs. 14.6% and 16.3%, p = 0.029).

CONCLUSIONS

Stent deferral was proved to be better than immediate stenting after recanalization of IRA, in achieving TIMI III flow, reducing risk of 6 months MACE, and restoration of myocardial function in a subset of STEMI patients presenting with large thrombus burden. While, no significant difference was found between both deferral times in final TIMI flow, or clinical outcomes.

Clinical Impact of Thrombus Aspiration and Interaction With D-Dimer Levels in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Objectives: To evaluate the effect of thrombus aspiration (TA) strategy on the outcomes and its interaction with D-dimer levels in patients with ST-segment elevation myocardial infarction (STEMI) during primary percutaneous coronary intervention (PCI) in "real-world" settings. Materials and Methods: This study included 1,295 patients with STEMI who had undergone primary PCI with or without TA between January 2013 and June 2017. Patients were first divided into a TA+PCI group and a PCI-only group, and the baseline characteristics and long-term mortality between the two groups were analyzed. Furthermore, we studied the effect of TA on the clinical outcomes of patients grouped according to quartiles of respective D-dimer levels. The primary outcome was all-cause mortality, and the secondary outcomes were new-onset heart failure (HF), rehospitalization, re-PCI, and stroke. Results: In the original cohort, there were no significant differences in all-cause mortality between the TA+PCI and PCI-only groups (hazard ratio, 0.789; 95% confidence interval, 0.556-1.120; p = 0.185). After a mean follow-up of 2.5 years, the all-cause mortality rates of patients in the TA + PCI and PCI-only groups were 8.5 and 16.2%, respectively. Additionally, differences between the two groups in terms of the risk of HF, re-PCI, rehospitalization, and stroke were non-significant. However, after dividing into quartiles, as the D-dimer levels increased, the all-cause mortality rate in the PCI group gradually increased (4.3 vs. 6.0 vs. 7.0 vs. 14.7%, p < 0.001), while the death rate in the TA+PCI group did not significantly differ (4.6 vs. 5.0 vs. 4.0 vs. 3.75%, p = 0.85). Besides, in the quartile 3 (Q3) and quartile 4 (Q4) groups, the PCI-only group was associated with a higher risk of all-cause mortality than that of the TA+PCI group (Q3: 4.0 vs. 7.0%, p = 0.029; Q4: 3.75 vs. 14.7%, p < 0.001). Moreover, the multivariate logistic regression analysis demonstrated that TA is inversely associated with the primary outcome in the Q4 group [odds ratio (OR), 0.395; 95% CI, 0.164-0.949; p = 0.038]. Conclusions: The findings of our real-world study express that routine manual TA during PCI in STEMI did not improve clinical outcomes overall. However, patients with STEMI with a higher concentration of D-dimer might benefit from the use of TA during primary PCI. Large-scale studies are recommended to confirm the efficacy of TA.

Co-morbidities and co-medications as confounders of cardioprotection-Does it matter in the clinical setting?

The translation of cardioprotection from robust experimental evidence to beneficial clinical outcome for patients suffering acute myocardial infarction or undergoing cardiovascular surgery has been largely disappointing. The present review attempts to critically analyse the evidence for confounders of cardioprotection in patients with acute myocardial infarction and in patients undergoing cardiovascular surgery. One reason that has been proposed to be responsible for such lack of translation is the confounding of cardioprotection by co-morbidities and co-medications. Whereas there is solid experimental evidence for such confounding of cardioprotection by single co-morbidities and co-medications, the clinical evidence from retrospective analyses of the limited number of clinical data is less robust. The best evidence for interference of co-medications is that for platelet inhibitors to recruit cardioprotection per se and thus limit the potential for further protection from myocardial infarction and for propofol anaesthesia to negate the protection from remote ischaemic conditioning in cardiovascular surgery. LINKED ARTICLES: This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.23/issuetoc.

Effect of intracoronary tirofiban following aspiration thrombectomy on infarct size, in patients with large anterior ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND

Myocardial recovery following primary percutaneous coronary intervention is often suboptimal despite of restoration of thrombolysis in myocardial infarction (TIMI) 3 flow, in part due to thrombus embolization which results in impairing microvascular reperfusion besides increasing infarct size. The purpose of the present study was to estimate the effect of aspiration thrombectomy followed by intracoronary delivery of tirofiban on decreasing the infarct size utilizing cardiac MRI (cMR) in large anterior ST-segment elevation myocardial infarction (STEMI) patients.

PATIENTS

A prospective randomized controlled study of 100 patients with large anterior STEMI were randomized to (Study group) using intracoronary tirofiban (intracoronary) and (control group) without intocoronary tirofiban. A 6 F thrombus aspiration catheter was used in all patients. Tirofiban was injected locally at the place of the highly thrombus burden through the aspiration device after flushing the aspiration device well.

RESULTS

Patients of intracoronary tirofiban group compared with control group had a significant difference in decreasing the infarct size at 30 days [median, 15.451 g - interquartile range (IQR), 17.404 gm - n = 50] vs (median, 43.828 g - IQR, 49.599 g - n = 50) P value = 0.002.

CONCLUSION

In patients early presented with large anterior STEMI, infarct size at 30 days was significantly decreased by intracoronary tirofiban delivered to the infarct lesion site followed aspiration thrombectomy.

Thrombus Embolisation: Prevention is Better than Cure

Thrombus embolisation complicating primary percutaneous coronary intervention in ST-elevation myocardial infarction is associated with an increase in adverse outcomes. However, there are currently no proven recommendations for intervention in the setting of large thrombus burden. In this review, we discuss the clinical implications of thrombus embolisation and angiographic predictors of embolisation, and provide an update of current evidence for some preventative strategies, both pharmacological and mechanical, in this setting.

Role of Intracoronary Fibrinolytic Therapy in Contemporary PCI Practice

Plaque rupture or plaque erosion leads to intracoronary thrombus formation resulting in coronary artery occlusion and ST-segment elevation myocardial infarction. Early restoration of blood flow in occluded coronary artery is the mainstay of therapy and it can be achieved by either thrombolytic therapy or primary percutaneous coronary intervention (P-PCI) or a combination of these two in many different ways. It has been proved that primary PCI is better than thrombolytic therapy in establishing early and effective recanalization of infarct related artery, reducing major adverse cardiovascular events (MACE) and increasing survival. There have been tremendous advances in PCI techniques over the years with newer stents, thrombectomy devices, and adjunctive pharmacotherapy. However, intracoronary thrombus continues to be the bane of interventional cardiologists. Failure of recanalization, suboptimal results, distal embolization, no reflow and impaired myocardial perfusion are some of the unresolved difficulties, regularly seen during PCI of patients with large intracoronary thrombus burden indicating an unmet need. This review focuses on emerging evidence about the usefulness of intracoronary thrombolytic therapy as an adjunct to PCI in patients with large intracoronary thrombus burden.

Efficacy and safety of thrombus aspiration in ST-segment elevation myocardial infarction: an updated systematic review and meta-analysis of randomised clinical trials

BACKGROUND:

The role of thrombus aspiration plus primary percutaneous coronary intervention in ST-segment elevation myocardial infarction remains controversial.

METHODS:

We performed a meta-analysis of 25 randomised controlled trials in which 21,740 ST-segment elevation myocardial infarction patients were randomly assigned to thrombus aspiration plus primary percutaneous coronary intervention or primary percutaneous coronary intervention. Study endpoints were: death, myocardial infarction, stent thrombosis and stroke.

RESULTS:

On pooled analysis, the risk of death (4.3% vs. 4.8%, odds ratio (OR) 0.90, 95% confidence interval (CI) 0.79-1.03; P=0.123), myocardial infarction (2.4% vs. 2.5%, OR 0.95, 95% CI 0.80-1.13; P=0.57) and stent thrombosis (1.3% vs. 1.6%, OR 0.80, 95% CI 0.63-1.01; P=0.066) was similar between thrombus aspiration plus primary percutaneous coronary intervention and primary percutaneous coronary intervention. The risk of stroke was higher in the thrombus aspiration plus primary percutaneous coronary intervention than the primary percutaneous coronary intervention group (0.84% vs. 0.59%, OR 1.401, 95% CI 1.004-1.954; P=0.047). However, on sensitivity analysis after removing the TOTAL trial, thrombus aspiration plus primary percutaneous coronary intervention was not associated with an increased risk of stroke (OR 1.01, 95% CI 0.58-1.78). The weak association between thrombus aspiration and stroke was also confirmed by the fact that the lower bound of the 95% CI was slightly below unity after removing either the study by Kaltoft or the ITTI trial. There was no interaction between the main study results and follow-up, evidence of coronary thrombus, or study sample size.

CONCLUSIONS:

In patients with ST-segment elevation myocardial infarction, thrombus aspiration plus primary percutaneous coronary intervention does not reduce the risk of death, myocardial infarction or stent thrombosis. Thrombus aspiration plus primary percutaneous coronary intervention is associated with an increased risk of stroke; however, this latter finding appears weak.

The pathophysiology of acute myocardial infarction and strategies of protection beyond reperfusion: a continual challenge

The incidence of ST segment elevation myocardial infarction (STEMI) has decreased over the last two decades in developed countries, but mortality from STEMI despite widespread access to reperfusion therapy is still substantial as is the development of heart failure, particularly among an expanding older population. In developing countries, the incidence of STEMI is increasing and interventional reperfusion is often not available. We here review the pathophysiology of acute myocardial infarction and reperfusion, notably the temporal and spatial evolution of ischaemic and reperfusion injury, the different modes of cell death, and the resulting coronary microvascular dysfunction. We then go on to briefly characterize the cardioprotective phenomena of ischaemic preconditioning, ischaemic postconditioning, and remote ischaemic conditioning and their underlying signal transduction pathways. We discuss in detail the attempts to translate conditioning strategies and drug therapy into the clinical setting. Most attempts have failed so far to reduce infarct size and improve clinical outcomes in STEMI patients, and we discuss potential reasons for such failure. Currently, it appears that remote ischaemic conditioning and a few drugs (atrial natriuretic peptide, exenatide, metoprolol, and esmolol) reduce infarct size, but studies with clinical outcome as primary endpoint are still underway.

Thrombus aspiration and prehospital ticagrelor administration in ST-elevation myocardial infarction: Findings from the ATLANTIC trial

BACKGROUND

The potential interactions between prehospital (pre-H) ticagrelor administration and thrombus aspiration (TA) in patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI) have never been studied. Therefore, we evaluated the potential benefit of TA and pre-H ticagrelor treatment in patients enrolled in the ATLANTIC trial (NCT01347580).

METHODS

This analysis included 1,630 patients who underwent primary PCI. Multivariate analysis was used to explore the potential association of TA and pre-H treatment to clinical outcomes. Potential interactions between TA and pre-H ticagrelor were also explored.

RESULTS

A total of 941 (57.7%) patients underwent TA. In adjusted multivariate logistic model, pre-H ticagrelor treatment was significantly associated with less frequent new MI or definite stent *thrombosis (ST) (odds ratio [OR] 0.43, 95% CI 0.20-0.92, P=.031), or definite ST (OR 0.26, 95% CI 0.07-0.91, P=.036) at 30 days. Patients treated with TA had higher frequency of Thrombolysis in Myocardial Infarction (TIMI) flow 0-1 compared with no-TA group (80.7% vs 51.9%, P<.0001). TA when also adjusted for TIMI flow 0-1 showed significant association only for higher bailout use of glycoprotein IIb/IIIa inhibitors (OR 1.72, 95% CI 1.18-2.50, P=.004) and more frequent 30-day TIMI major bleeding (OR 2.92, 95% CI 1.10-7.76, P=.032). No significant interactions between TA and pre-H ticagrelor were present for the explored end points.

CONCLUSIONS

TA when left to physicians' discretion was used in high-risk patients, was associated with bailout use of glycoprotein IIb/IIIa inhibitors and TIMI major bleeding, and had no impact on 30-day clinical outcomes. Conversely, pre-H ticagrelor treatment predicted lower 30-day rates of ST or new MI without interaction with TA.

Effect of Shorter Door-to-Balloon Times Over 20 Years on Outcomes of Patients With Anterior ST-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Cardiovascular disease remains the most common cause of mortality. We studied the change in outcomes for anterior ST-elevation myocardial infarction (STEMI) between 1995 and 2014. Over the past 20 years, 1,658 patients presenting to our center with anterior STEMI underwent primary percutaneous coronary intervention within 12 hours of presentation. We divided these into 4 quartiles, 1995 to 1999 (n = 312), 2000 to 2004 (n = 408), 2005 to 2009 (n = 428), and 2010 to 2014 (n = 510). Across the 4 quartiles, mean age decreased (64.4, 62, 60.3, and 60 years, p <0.01). In all groups, there was a significant rise in prevalence of smoking, hypertension, and obesity. The median length of hospital stay decreased (6, 4.4, 4.2, and 3.6 days, p <0.01), as did the median door-to-balloon time (DBT) (217, 194, 135, and 38 minutes, p <0.01). Thirty-day and 1-year mortality improved over time (14.4%, 11.8%, 8.4%, and 7.8%; and 20.5%, 16.4%, 15.9%, and 13.9%) (p = 0.01 both). Also, 3-year mortality improved (25.3%, 21.6%, 21.3%, and 16.5%, p = 0.02). After adjusting for age, gender, co-morbidities, ejection fraction, clinical shock, and mitral regurgitation, shorter DBT was associated with lower long-term mortality (compared with DBT <60 minutes; 60 to 90 minutes hazard ratio [HR] 1.67, 95% confidence interval [CI] 0.93 to 3.00, p = 0.084; 90 to 120 minutes, HR 1.74, 95% CI 1.02 to 2.95, p = 0.04; >120 minutes, HR 1.91, 95% CI 1.23 to 2.96, p = 0.004). In conclusion, over the past 2 decades, long-term outcomes improved in patients presenting with anterior STEMI associated with shortening of DBT.

Can thrombectomy and catheters used increase angiographically visible distal embolization in ST elevation myocardial infarction?

INTRODUCTION

Primary percutaneous coronary intervention (PPCI) is the preferred treatment of ST segment elevation myocardial infarction (STEMI). Manual thrombectomy catheters developed to prevent distant embolization are theoretically attractive; however, their clinical efficacy remains controversial. The effects of manual thrombectomy catheters on angiographically visible distal embolisation (AVDE) have not been studied so far. The aim of this study was to evaluate the effects of manual thrombectomy during PPCI on AVDE and to investigate whether there are differences in the incidence of AVDE according to the catheters used.

MATERIAL AND METHODS

Six hundred thirty-six consecutive patients undergoing primary PCI were included in the study between January 2010 and December 2012. Patients were divided into two groups: the PCI only group (465 patients) and the PCI plus manual thrombectomy group (171 patients).

RESULTS

Thrombus aspiration was associated with higher AVDE (13.55% vs. 26.9%, p = 0.0001), lower thrombolysis in myocardial infarction frame rate (2.49 ±0.86 vs. 2.79 ±0.57, p = 0.0001), lower myocardial blush grade (2.31 ±0.87 vs. 2.47 ±0.7, p = 0.016), lower ejection fraction (EF) (49.9 ±8.5 vs. 46.1 ±9.6, p = 0.0001) and higher maximal troponin release (15.7 ±16 vs. 9.4 ±11, p = 0.0001). No difference was observed in terms of mortality between the groups in follow-up (5.2% vs. 9.03%, p = 0.12). Angiographically visible distal embolisation was observed more frequently with Invatec catheters (p = 0.0001).

CONCLUSIONS

Angiographically visible distal embolisation during primary PCI occurs in a significant number of patients treated with manual thrombectomy. The results indicated that the incidence of AVDE may be different depending on the thrombectomy catheters used.

Determinants of slow flow following stent implantation in intravascular ultrasound-guided primary percutaneous coronary intervention

Slow flow is a serious complication in primary percutaneous coronary intervention (PCI) and is associated with poor clinical outcomes. Intravascular ultrasound (IVUS)-guided PCI may improve clinical outcomes after drug-eluting stent implantation. The purpose of this study was to seek the factors of slow flow following stent implantation, including factors related to IVUS-guided primary PCI. The study population consisted of 339 ST-elevation myocardial infarction patients, who underwent stent deployment with IVUS. During PCI, 56 patients (16.5%) had transient or permanent slow flow. Multivariate logistic regression analysis showed age (OR 1.04, 95% CI 1.01-1.07, P = 0.01), low attenuation plaque on IVUS (OR 3.38, 95% CI 1.70-6.72, P = 0.001), initial Thrombolysis In Myocardial Infarction (TIMI) flow grade 2 (vs. TIMI 0: OR 0.44, 95% CI 0.20-0.99, P = 0.046), and the ratio of stent diameter to vessel diameter (per 0.1 increase: OR 2.63, 95% CI 1.84-3.77, P < 0.001) were significantly associated with slow flow. A ratio of stent diameter to vessel diameter of 0.71 had an 80.4% sensitivity and 56.9% specificity to predict slow flow. There was no significant difference in ischemic-driven target vessel revascularization between the modest stent expansion (ratio of stent diameter to vessel diameter <0.71) and aggressive stent expansion (ratio of stent diameter to vessel diameter ≥0.71) strategies. Unlike other variables, the ratio of stent diameter to vessel diameter was the only modifiable factor. The modest stent expansion strategy should be considered to prevent slow flow following stent implantation in IVUS-guided primary PCI.

The Coronary Circulation as a Target of Cardioprotection

The atherosclerotic coronary vasculature is not only the culprit but also a victim of myocardial ischemia/reperfusion injury. Manifestations of such injury are increased vascular permeability and edema, endothelial dysfunction and impaired vasomotion, microembolization of atherothrombotic debris, stasis with intravascular cell aggregates, and finally, in its most severe form, capillary destruction with hemorrhage. In animal experiments, local and remote ischemic pre- and postconditioning not only reduce infarct size but also these manifestations of coronary vascular injury, as do drugs which recruit signal transduction steps of conditioning. Clinically, no-reflow is frequently seen after interventional reperfusion, and it carries an adverse prognosis. The translation of cardioprotective interventions to clinical practice has been difficult to date. Only 4 drugs (brain natriuretic peptide, exenatide, metoprolol, and esmolol) stand unchallenged to date in reducing infarct size in patients with reperfused acute myocardial infarction; unfortunately, for these drugs, no information on their impact on the ischemic/reperfused coronary circulation is available.

Deferred Versus Immediate Stenting in Patients With ST-Segment Elevation Myocardial Infarction: A Systematic Review and Meta-Analysis

Background

A number of studies have evaluated the efficacy of deferred stenting vs immediate stenting in patients with ST‐segment elevation myocardial infarction, but the findings were not consistent across these studies. This meta‐analysis aims to assess optimal treatment strategies in patient with ST‐segment elevation myocardial infarction.

Methods and Results

We searched the PubMed, EMBASE, and the Cochrane Library for studies that assessed deferred vs immediate stenting in patients with ST‐segment elevation myocardial infarction. Nine studies including 1456 patients in randomized controlled trials and 719 patients in observational studies were included in the meta‐analysis. No significant differences were observed in the incidence of no‐ or slow‐reflow between deferred stenting and immediate stenting in randomized controlled trials (odds ratio [OR] 0.51, 95%CI 0.17‐1.53, P=0.23, I²=70%) but not in observational studies (OR 0.13, 95%CI 0.06‐0.31, P<0.0001, I²=0%). Deferred stenting was associated with an increase in long‐term left ventricular ejection fraction (weighted mean difference 1.90%, 95%CI 0.77‐3.03, P=0.001, I²=0%). No significant differences were observed in the rates of major adverse cardiovascular events (OR 0.53, 95%CI 0.27‐1.01, P=0.06 [randomized OR 0.98, 95%CI 0.73‐1.30, P=0.87, I²=0%; nonrandomized OR 0.30, 95%CI 0.15‐0.58, P=0.0004, I²=0%]), major bleeding (OR=0.1.61, 95%CI 0.70‐3.69, P=0.26, I²=0%), death (OR=0.78, 95%CI 0.53‐1.15, P=0.22, I²=0%), MI (OR=0.97, 95%CI 0.34‐2.78, P=0.96, I²=35%) and target vessel revascularization (OR 0.97, 95%CI 0.40‐2.37, P=0.95, I²=24%), between deferred and immediate stenting.

Conclusions

Compared with immediate stenting, a deferred‐stenting strategy did not reduce the occurrence of no‐ or slow‐reflow, death, myocardial infarction, or repeat revascularization compared with immediate stenting in patients with ST‐segment elevation myocardial infarction, but showed an improved left ventricular function in the long term.

Aspiration Thrombectomy in Patients Undergoing Primary Angioplasty for ST Elevation Myocardial Infarction: An Updated Meta-Analysis

BACKGROUND

The Trial of Routine Aspiration Thrombectomy with PCI versus PCI alone in patients with STEMI (TOTAL trial) refuted the salutary effect of routine aspiration thrombectomy (AT) in PPCI for patients with ST-elevation myocardial infarction (STEMI).

OBJECTIVES

We performed an updated meta-analysis to assess clinical outcomes with AT prior to PPCI compared with conventional PPCI alone including the additional trial data.

METHODS AND RESULTS

Clinical trials (n = 20) that randomized patients (n = 21,281) with STEMI between Routine AT (n = 10,619) and PPCI (n = 10,662) were pooled. There was no difference in all-cause mortality between the 2 groups (RR: 0.89, 95%CI: 0.78-1.01, P = 0.08). Stratifying by follow up at 1-month (RR: 0.87, 95%CI: 0.69-1.10, P = 0.25), up to 6 months (RR: 0.91, 95%CI: 0.74-1.13, P = 0.39 and beyond 6 months (RR: 0.88, 95%CI: 0.74-1.05, P = 0.16) yielded similar results. There was a statistically significant increase risk of stoke rate in the AT arm (RR: 1.51, 95%CI: 1.01-2.25, P = 0.04). The 2 groups were similar with regards to target vessel revascularization (0.94, 95%CI: 0.83-1.06, P = 0.28) recurrent MI (RR: 0.96, 95%CI: 0.80-1.16, P = 0.68, MACE events (RR: 0.91 95%CI: 0.81-1.02, P = 0.11), early (0.59, 95%CI: 0.23-1.50, P = 0.27) and late (RR: 0.91, 95%CI: 0.69-1.18, P = 0.47) stent thrombosis and net clinical benefit (RR 0.99, 95%CI: 0.91-1.07, P = 0.76).

CONCLUSION

Routine AT prior to PPCI in STEMI is associated with higher risk of stroke. There is no statistical difference in clinical outcome parameters of mortality, major adverse cardiac events, target vessel revascularization, stent thrombosis, and net clinical benefit between AT and PCI alone.

Aspiration thrombectomy prior to percutaneous coronary intervention in ST-elevation myocardial infarction: a systematic review and meta-analysis

BACKGROUND

Trials of aspiration thrombectomy (AT) prior to primary percutaneous intervention (PCI) in patients with ST-segment elevation MI (STEMI) have shown apparently inconsistent results and therefore generated uncertainty and controversy. To summarize the effects of AT prior to PCI versus conventional PCI in STEMI patients.

METHODS

Searches of MEDLINE, EMBASE and CENTRAL to June 2015 and review of reference lists of previous reviews. We included randomized controlled trials (RCTs) comparing AT prior to PCI with conventional PCI alone. Pairs of reviewers independently screened eligible articles; extracted data; and assessed risk of bias. We used the GRADE approach to rate overall certainty of the evidence.

RESULTS

Among 73 potential articles identified, 20 trials including 21,660 patients were eligible; data were complete for 20,866 patients. Moderate-certainty evidence suggested a non statistically significant decrease in overall mortality (risk ratio (RR) 0.89, 95 % confidence interval, 0.78 to 1.01, risk difference (RD) 4/1,000 over 6 months), no impact on recurrent MI (RR 0.94, 95 % CI, 0.79 to 1.12) or major bleeding (RR 1.02, 95 % CI, 0.78 to 1.35), and an increase in stroke (RR 1.56, 95 % CI, 1.09 to 2.24, RD 3/1,000 over 6 months).

CONCLUSIONS

Moderate certainty evidence suggests aspiration thrombectomy is associated with a possible small decrease in mortality (4 less deaths/1000 over 6 months) and a small increase in stroke (3 more strokes/1000 over 6 months). Because absolute effects are very small and closely balanced, thrombectomy prior to primary PCI should not be used as a routine strategy.

Deferred versus conventional stent implantation in patients with ST-segment elevation myocardial infarction (DANAMI 3-DEFER): an open-label, randomised controlled trial

BACKGROUND

Despite successful treatment of the culprit artery lesion by primary percutaneous coronary intervention (PCI) with stent implantation, thrombotic embolisation occurs in some cases, which impairs the prognosis of patients with ST-segment elevation myocardial infarction (STEMI). We aimed to assess the clinical outcomes of deferred stent implantation versus standard PCI in patients with STEMI.

METHODS

We did this open-label, randomised controlled trial at four primary PCI centres in Denmark. Eligible patients (aged >18 years) had acute onset symptoms lasting 12 h or less, and ST-segment elevation of 0·1 mV or more in at least two or more contiguous electrocardiographic leads or newly developed left bundle branch block. Patients were randomly assigned (1:1), via an electronic web-based system with permuted block sizes of two to six, to receive either standard primary PCI with immediate stent implantation or deferred stent implantation 48 h after the index procedure if a stabilised flow could be obtained in the infarct-related artery. The primary endpoint was a composite of all-cause mortality, hospital admission for heart failure, recurrent infarction, and any unplanned revascularisation of the target vessel within 2 years' follow-up. Patients, investigators, and treating clinicians were not masked to treatment allocation. We did analysis by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01435408.

FINDINGS

Between March 1, 2011, and Feb 28, 2014, we randomly assigned 1215 patients to receive either standard PCI (n=612) or deferred stent implantation (n=603). Median follow-up time was 42 months (IQR 33-49). Events comprising the primary endpoint occurred in 109 (18%) patients who had standard PCI and in 105 (17%) patients who had deferred stent implantation (hazard ratio 0·99, 95% CI 0·76-1·29; p=0·92). Procedure-related myocardial infarction, bleeding requiring transfusion or surgery, contrast-induced nephopathy, or stroke occurred in 28 (5%) patients in the conventional PCI group versus 27 (4%) patients in the deferred stent implantation group, with no significant differences between groups.

INTERPRETATION

In patients with STEMI, routine deferred stent implantation did not reduce the occurrence of death, heart failure, myocardial infarction, or repeat revascularisation compared with conventional PCI. Results from ongoing randomised trials might shed further light on the concept of deferred stenting in this patient population.

FUNDING

Danish Agency for Science, Technology and Innovation, and Danish Council for Strategic Research.

Is Aspiration Thrombectomy Beneficial in Patients Undergoing Primary Percutaneous Coronary Intervention? Meta-Analysis of Randomized Trials

BACKGROUND

It is unclear whether intravenous glycoprotein IIb/IIIa inhibitors or ischemic time might modify any clinical benefits observed with aspiration thrombectomy before primary percutaneous coronary intervention (PCI) in patients with ST-segment-elevation myocardial infarction.

METHODS AND RESULTS

Electronic databases were searched for trials that randomized ST-segment-elevation myocardial infarction patients to aspiration thrombectomy before PCI versus conventional PCI. Summary estimates were constructed using a DerSimonian-Laird model. Seventeen trials with 20 960 patients were available for analysis. When compared with conventional PCI, aspiration thrombectomy was not associated with a significant reduction in the risk of mortality 2.8% versus 3.2% (risk ratio [RR], 0.89; 95% confidence interval [CI], 0.76-1.04; P=0.13), reinfarction 1.3% versus 1.4% (RR, 0.93; 95% CI, 0.73-1.17; P=0.52), the combined outcome of mortality or reinfarction 4.1% versus 4.6% (RR, 0.90; 95% CI, 0.79-1.02; P=0.11), or stent thrombosis 0.9% versus 1.2% (RR, 0.82; 95% CI, 0.62-1.08; P=0.15). Aspiration thrombectomy was associated with a nonsignificant increase in the risk of stroke 0.6% versus 0.4% (RR, 1.45; 95% CI, 0.96-2.21; P=0.08). Meta-regression analysis did not identify a difference for the log RR of mortality, reinfarction, and the combined outcome of mortality or reinfarction with intravenous glycoprotein IIb/IIIa inhibitors (P=0.17, 0.70, and 0.50, respectively) or with ischemic time (P=0.29, 0.66, and 0.58, respectively).

CONCLUSIONS

Aspiration thrombectomy before primary PCI is not associated with any benefit on clinical end points and might increase the risk of stroke. Concomitant administration of intravenous glycoprotein IIb/IIIa inhibitors and ischemic time did not seem to influence any potential benefits observed with aspiration thrombectomy.

Manual Aspiration Thrombectomy in Acute Myocardial Infarction: A Clinical Experience

Multiple clinical studies have failed to establish the role of routine use of thrombectomy in ST-elevation myocardial infarction (STEMI) patients. There is a paucity of data on the impact of thrombectomy in unselected STEMI patients outside clinical trials. We sought to evaluate the clinical variables and outcomes associated with the performance of thrombectomy in STEMI patients. We retrospectively examined the clinical outcomes in all STEMI patients who underwent successful percutaneous intervention (PCI) at our center. Patients were divided into two groups, one with patients who underwent conventional PCI and another with patients who had thrombus aspiration in addition to conventional PCI. We compared the baseline clinical characteristics, laboratory investigations, re-infarction rates, and all-cause mortality. Total 477 consecutive STEMI patients were identified. Overall, 29% (139) of the patients underwent conventional PCI and 71% (338) of the patients were treated with aspiration thrombectomy and PCI. In addition to the presence of thrombus, patients with nonanterior infarction, and patients with hemodynamic instability requiring intra-aortic balloon pump support were more likely to undergo thrombectomy. Thrombectomy was associated with higher enzymatic infarction (creatine kinase: 2,796 [2,575] vs. 1,716 [1,662]; p < 0.0001; CK-MB: 210.6 [156.0] vs. 142.0 [121.9], p < 0.0001). However, thrombectomy was not associated with any difference in 30 day reinfarction rate (3.3 vs. 2.9%, p = 0.83), mortality (5.0 vs. 7.2%, p = 0.35), or composite of death and 30 day reinfarction (7.7 vs. 9.4%, p = 0.55). We observed that STEMI patients with anterior infarction and hemodynamic instability were more likely to undergo thrombectomy during primary PCI.

Thrombus Aspiration in STEMI

OPINION STATEMENT

ST-segment elevation myocardial infarction (STEMI) remains an important cause of morbidity and mortality. In the USA, the development of an organized STEMI network has allowed STEMI patients greater access to primary PCI. The most important goal in the management of STEMI is timely reperfusion and establishment of normal coronary flow. However, periprocedural thrombus embolization, which can obstruct the distal microvasculature and impair tissue perfusion, is associated with unfavorable outcomes. Over the last years, aspiration thrombectomy has emerged as a novel technique to prevent distal coronary thromboembolism during primary PCI. The initial excitement after the publication of the TAPAS trial changed the practice paradigm among interventional community worldwide. Aspiration thrombectomy was recommended by several society guidelines and became the "standard of care" during primary PCI. However, recent data and publication of two large randomized controlled trials questioned the effectiveness (TASTE trial) and the safety (TOTAL trial) of this technique. Therefore, the recent ACC/AHA/SCAI-focused update document recommended against the routine use of manual thrombectomy during primary PCI. This review will summarize recent data and trials regarding thrombus aspiration in STEMI.

Thrombus aspiration in acute myocardial infarction: concepts, clinical trials, and current guidelines

The pathogenesis that underlies acute myocardial infarction is complex and multifactorial. One of the most important components, however, is the role of thrombus formation following atherosclerotic plaque rupture, leading to sudden coronary occlusion and subsequent ischemia and infarction. Thrombus aspiration provides the opportunity of intracoronary clot extraction with the aim to improve coronary and myocardial perfusion, by reducing the risk of no-reflow secondary to distal embolization of thrombus. The utility of thrombus aspiration during primary percutaneous coronary intervention has been assessed in an increasing number of observational and randomized studies. This article reviews the contemporary data and provides insights into the validity of thrombus aspiration in the setting of acute myocardial infarction.

Outcomes after thrombus aspiration for ST elevation myocardial infarction: 1-year follow-up of the prospective randomised TOTAL trial

BACKGROUND

Two large trials have reported contradictory results at 1 year after thrombus aspiration in ST elevation myocardial infarction (STEMI). In a 1-year follow-up of the largest randomised trial of thrombus aspiration, we aimed to clarify the longer-term benefits, to help guide clinical practice.

METHODS

The trial of routine aspiration ThrOmbecTomy with PCI versus PCI ALone in Patients with STEMI (TOTAL) was a prospective, randomised, investigator-initiated trial of routine manual thrombectomy versus percutaneous coronary intervention (PCI) alone in 10,732 patients with STEMI. Eligible adult patients (aged ≥18 years) from 87 hospitals in 20 countries were enrolled and randomly assigned (1:1) within 12 h of symptom onset to receive routine manual thrombectomy with PCI or PCI alone. Permuted block randomisation (with variable block size) was done by a 24 h computerised central system, and was stratified by centre. Participants and investigators were not masked to treatment assignment. The trial did not show a difference at 180 days in the primary outcome of cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure. However, the results showed improvements in the surrogate outcomes of ST segment resolution and distal embolisation, but whether or not this finding would translate into a longer term benefit remained unclear. In this longer-term follow-up of the TOTAL study, we report the results on the primary outcome (cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure) and secondary outcomes at 1 year. Analyses of the primary outcome were by modified intention to treat and only included patients who underwent index PCI. This trial is registered with ClinicalTrials.gov, number NCT01149044.

FINDINGS

Between Aug 5, 2010, and July 25, 2014, 10,732 eligible patients were enrolled and randomly assigned to thrombectomy followed by PCI (n=5372) or to PCI alone (n=5360). After exclusions of patients who did not undergo PCI in each group (337 in the PCI and thrombectomy group and 331 in the PCI alone group), the final study population comprised 10,064 patients (5035 thrombectomy and 5029 PCI alone). The primary outcome at 1 year occurred in 395 (8%) of 5035 patients in the thrombectomy group compared with 394 (8%) of 5029 in the PCI alone group (hazard ratio [HR] 1·00 [95% CI 0·87-1·15], p=0·99). Cardiovascular death within 1 year occurred in 179 (4%) of the thrombectomy group and in 192 (4%) of 5029 in the PCI alone group (HR 0·93 [95% CI 0·76-1·14], p=0·48). The key safety outcome, stroke within 1 year, occurred in 60 patients (1·2%) in the thrombectomy group compared with 36 (0·7%) in the PCI alone group (HR 1·66 [95% CI 1·10-2·51], p=0·015).

INTERPRETATION

Routine thrombus aspiration during PCI for STEMI did not reduce longer-term clinical outcomes and might be associated with an increase in stroke. As a result, thrombus aspiration can no longer be recommended as a routine strategy in STEMI.

FUNDING

Canadian Institutes of Health Research, Canadian Network and Centre for Trials Internationally, and Medtronic Inc.

Rheolityc thrombectomy in acute myocardial infarction: Effect on microvascular obstruction, infarct size, and left ventricular remodeling

OBJECTIVES

We sought to analyze whether rheolytic thrombectomy (RT) in comparison with manual thrombus aspiration (MTA) may reduce microvascular obstruction (MVO), infarct size (IS), and left ventricular (LV) remodeling in ST-elevation myocardial infarction (STEMI).

BACKGROUND

Conflicting results have been reported as to whether MTA reduces MVO and IS.

METHODS AND RESULTS

Eighty STEMI reperfused by primary angioplasty and abciximab were randomly allocated (1:1) to RT or MTA. Cardiac magnetic resonance imaging (MRI) was performed in 37 patients (19 RT) and after 1 year in 19 (9 RT); baseline, 1- and 6-month 2D-echo was performed in all patients. MVO and IS were measured 8 min after gadolinium injection with late enhancement sequences and were analyzed quantitatively at a core laboratory blinded to randomization. At baseline TIMI thrombus grade were similar (RT: 4.47 ± 0.84 vs. MTA: 4.67 ± 0.76, P = 0.453). After thrombectomy, thrombus grade decreased to 1.11 ± 1.04 in RT vs. 2.17 ± 1.29 in MTA arm (P = 0.009). RT compared with MTA did not reduced significantly myocardial IS [12.2% (6.4-22.1) vs. 19.0% (7-28.5), P = 0.224] as well as the extent of MVO [0.0% (0.0-0.17) vs. 0.6% (0.0-1.4), P = 0.117], but a trend toward a lower incidence of MVO (16% vs. 44%, P = 0.056) and a less LV remodeling rate were found in RT arm (11% vs. 24%, P < 0.140).

CONCLUSION

RT in comparison with MTA was more effective in thrombus removal, but it did not reduced significantly the IS and the extent of MVO. However, a trend toward a lower incidence of MVO and a better preservation of LV volumes were found in RT arm. © 2015 Wiley Periodicals, Inc.

Intracoronary Infusion of Thioflavin-S to Study Microvascular Obstruction in a Model of Myocardial Infarction

INTRODUCTION AND OBJECTIVES

Microvascular obstruction exerts deleterious effects after myocardial infarction. To elucidate the role of ischemia-reperfusion injury on the occurrence and dynamics of microvascular obstruction, we performed a preliminary methodological study to accurately define this process in an in vivo model.

METHODS

Myocardial infarction was induced in swine by means of 90-min of occlusion of the mid left anterior descending coronary artery using angioplasty balloons. Intracoronary infusion of thioflavin-S was applied and compared with traditional intra-aortic or intraventricular instillation. The left anterior descending coronary artery perfused area and microvascular obstruction were quantified in groups with no reperfusion (thioflavin-S administered through the lumen of an inflated over-the-wire balloon) and with 1-min, 1-week, and 1-month reperfusion (thioflavin-S administered from the intracoronary catheter after balloon deflation).

RESULTS

In comparison with intra-aortic and intraventricular administration, intracoronary infusion of thioflavin-S permitted a much clearer assessment of the left anterior descending coronary artery perfused area and of microvascular obstruction. Ischemia-reperfusion injury exerted a decisive role on the occurrence and dynamics of microvascular obstruction. The no-reperfusion group displayed completely preserved perfusion. With the same duration of coronary occlusion, microvascular obstruction was already detected in the 1-min reperfusion group (14%±7%), peaked in the 1-week reperfusion group (21%±7%), and significantly decreased in the 1-month reperfusion group (4%±3%; P<.001).

CONCLUSIONS

We present proof-of-concept evidence on the crucial role of ischemia-reperfusion injury on the occurrence and dynamics of microvascular obstruction. The described porcine model using intracoronary injection of thioflavin-S permits accurate characterization of microvascular obstruction after myocardial infarction.

Clinical Outcomes of Manual Aspiration Thrombectomy in Patients with Acute Myocardial Infarction: An Updated Meta-Analysis

Background: Recent trials on manual aspiration thrombectomy (AT) in patients with ST-elevation myocardial infarction did not show any significant benefits of AT. Aims: The present meta-analysis was designed to systematically evaluate prospective randomized trials and assess the effects of AT on all-cause mortality, major cardiovascular events (MACE), target vessel revascularization, myocardial reinfarction, stroke and surrogate myocardial perfusion markers. Methods and Results: We conducted an EMBASE and MEDLINE search for studies in which patients were randomized to treatment with AT plus primary percutaneous coronary intervention (PCI) versus PCI. We identified 16 prospective randomized trials which enrolled 10,437 controls that underwent conventional PCI and 10,385 patients who underwent PCI with AT with an average follow-up duration of 5.8 months. A significant reduction in MACE with AT was noted (OR 0.91; 95% CI 0.82-0.99; p = 0.04). In spite of improved TIMI 3 and myocardial blush grade 3 rates, AT did not significantly reduce all-cause mortality, target-vessel revascularization and myocardial infarction. Stroke rates were increased with AT. Conclusion: The results of this large meta-analysis of 20,822 patients suggest that adjunctive AT to PCI may be associated with improved myocardial reperfusion but limited benefits related to the clinical end-points.

ST-elevation myocardial infarction, thrombus aspiration, and different invasive strategies. A TASTE trial substudy

BACKGROUND

The clinical effect of thrombus aspiration in ST-elevation myocardial infarction may depend on the type of aspiration catheter and stenting technique.

METHODS AND RESULTS

The multicenter, prospective, randomized, open-label trial Thrombus Aspiration in ST-Elevation myocardial infarction in Scandinavia (TASTE) did not demonstrate a clinical benefit of thrombus aspiration compared to percutaneous coronary intervention alone. We assessed the effect of type of aspiration device, stent type, direct stenting, and postdilatation on outcomes at 1 year. There was no difference in all-cause mortality, between the 3 most frequently used aspiration catheters (Eliminate [Terumo] 5.4%, Export [Medtronic] 5.0%, Pronto [Vascular Solutions] 4.5%) in patients randomized to thrombus aspiration. There was no difference in mortality between directly stented patients randomized to thrombus aspiration compared to patients randomized to percutaneous coronary intervention only (risk ratio 1.08, 95% CI 0.70 to 1.67, P=0.73). Similarly, there was no difference in mortality between the 2 randomized groups for patients receiving drug-eluting stents (risk ratio 0.89, 95% CI 0.63 to 1.26, P=0.50) or for those treated with postdilation (risk ratio 0.72, 95% CI 0.49 to 1.07, P=0.11). Furthermore, there was no difference in rehospitalization for myocardial infarction or stent thrombosis between the randomized arms in any of the subgroups.

CONCLUSIONS

In patients with ST-elevation myocardial infarction randomized to thrombus aspiration, the type of aspiration catheter did not affect outcome. Stent type, direct stenting, or postdilation did not affect outcome irrespective of treatment with thrombus aspiration and percutaneous coronary intervention or percutaneous coronary intervention alone.

CLINICAL TRIAL REGISTRATION

URL: ClinicalTrials.gov. Unique identifier: NCT01093404, https://clinicaltrials.gov/ct2/show/NCT01093404.

The Third DANish Study of Optimal Acute Treatment of Patients with ST-segment Elevation Myocardial Infarction: Ischemic postconditioning or deferred stent implantation versus conventional primary angioplasty and complete revascularization versus treatment of culprit lesion only: Rationale and design of the DANAMI 3 trial program

BACKGROUND

In patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction, ischemic postconditioning has been shown to reduce infarct size, but the effect on clinical outcome has not been tested in a large randomized trial. In addition, deferring stent implantation in the infarct-related lesion 1 to 3 days after acute opening of the infarct-related artery could have protective effects, by reducing the risk of injury caused by distal embolization and microvascular obstruction. Finally, a considerable fraction of patients present with lesions in other coronary artery branches than the infarct-related artery. Whether a strategy of complete or partial revascularization of these patients should be preferred remains uncertain.

STUDY DESIGN

The DANAMI 3 trial program was designed to investigate 3 different randomized treatment strategies in patients with ST-segment elevation myocardial infarction: (1) ischemic postconditioning versus conventional treatment with a primary end point of death and hospitalization for heart failure; (2) deferring stent implantation in the infarct-related lesion versus conventional treatment with a primary end point of death, hospitalization for heart failure, reinfarction, and repeat revascularization; and (3) treatment of the culprit lesion only versus fractional flow reserve-guided complete revascularization in patients with multivessel disease, with a primary end point of death, reinfarction, and repeat revascularization.

SUMMARY

The DANAMI 3 trial program will determine whether either of 2 approaches to reduce reperfusion injury and distal microvascular obstruction with postconditioning or deferred stent implantation will translate into improved clinical outcome and whether patients with multivessel disease undergoing primary percutaneous coronary intervention will benefit from a strategy of complete or partial revascularization.

Thrombus aspiration in patients with ST elevation myocardial infarction: meta-analysis of 16 randomized trials

OBJECTIVE

The mortality rate is high in some patients undergoing primary percutaneous coronary intervention (PPCI) because of ineffective epicardial and myocardial perfusion. The use of thrombus aspiration (TA) might be beneficial in this group but there is contradictory evidence in current trials. Therefore, using PRISMA statement, we performed a meta-analysis that compares PPCI+TA with PPCI alone.

METHODS

Sixteen studies in which PPCI (n=5262) versus PPCI+TA (n=5256) were performed, were included in this meta-analysis. We calculated the risk ratio (RR) for epicardial and myocardial perfusion, such as the Thrombolysis In myocardial Infarction (TIMI) flow, myocardial blush grade (MBG) and stent thrombosis (ST) resolution (STR), and clinical outcomes, such as all-cause death, recurrent infarction (Re-MI), target vessel revascularization/target lesion revascularization (TVR/TLR), stent thrombosis (ST), and stroke.

RESULTS

Postprocedural TIMI-III flow frequency, postprocedural MBG II-III flow frequency, and postprocedural STR were significantly high in TA+PPCI compared with the PPCI alone group. However, neither all-cause mortality [6.6% vs. 7.4%, RR=0.903, 95% confidence interval (CI): 0.785-1.038, p=0.149] nor Re-MI (2.3% vs. 2.6%, RR=0.884, 95% CI: 0.693-1.127, p=0.319), TVR/TLR (8.2% vs. 8.0%, RR=1.028, 95% CI: 0.900-1.174, p=0.687), ST (0.93% vs. 0.90%, RR=1.029, 95% CI: 0.668-1.583, p=0.898), and stroke (0.5% vs. 0.5%, RR=1.073, 95% CI: 0.588-1.959, p=0.819) rates were comparable between the groups.

CONCLUSION

This meta-analysis is the first updated analysis after publishing the 1-year result of the "Thrombus Aspiration during ST-Segment Elevation Myocardial Infarction" trial, and it showed that TA did not reduce the rate of all-cause mortality, Re-MI, TVR/TLR, ST, and stroke.

Association between hyperglycemia at admission and microvascular obstruction in patients with ST-segment elevation myocardial infarction

BACKGROUND

Blood glucose level at admission in ST-segment elevation myocardial infarction (STEMI) is a predictor of heart failure and mortality. A previous study showed the association between hyperglycemia and microvascular dysfunction using myocardial contrast echocardiography. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) can demonstrate microvascular obstruction (MVO) as the area with hypointense core within LGE. This study was performed to investigate the association between hyperglycemia at admission and MVO using CMR in patients with STEMI.

METHODS

Ninety-three patients with first STEMI who were treated by percutaneous coronary intervention (PCI) were included. CMR was performed within 7 days after PCI. Venous blood was collected routinely immediately after admission for plasma glucose determination before intravenous injection of some medications. Samples were analyzed in the hospital's central laboratory. We performed LGE-CMR to assess the presence of MVO.

RESULTS

MVO was found in 34 (37%) of all 93 patients; their glucose level at admission was significantly higher than that of patients who did not exhibit MVO [204 (153-267)mg/dl vs. 157 (127-200)mg/dl, p=0.002]. There were no differences in glycosylated hemoglobin and incidence of diabetes mellitus between the two groups. A multivariable logistic regression analysis showed that glucose level at admission was an independent predictor of MVO (odds ratio, 1.014; 95% confidence interval, 1.004 to 1.023; p=0.006). The glucose level at admission 190mg/dl was the best threshold value for identifying MVO. The occurrence of MVO was significantly higher in the patients with glucose level at admission ≧190mg/dl compared with the patients with glucose level <190mg/dl [18 (53%) vs. 16 (27%), p=0.023].

CONCLUSIONS

Hyperglycemia at admission in STEMI patients who were treated by PCI was associated with the presence of MVO assessed by LGE-CMR.

Effect of coronary thrombus aspiration during primary percutaneous coronary intervention on one-year survival (from the FAST-MI 2010 registry)

Results from randomized trials evaluating thrombus aspiration (TA) in patients with ST-elevation myocardial infarction (STEMI) are conflicting. We assessed 1-year survival in STEMI patients participating in the French Registry of Acute ST-Elevation and non-ST-Elevation Myocardial Infarction (FAST-MI) 2010 according to the use of TA during primary percutaneous coronary intervention (PCI). FAST-MI 2010 is a nationwide French registry that included 4,169 patients with acute myocardial infarction at the end of 2010 in 213 centers. Of those, 2,087 patients had STEMI, of whom 1,538 had primary PCI, with TA used in 671 (44%). Patients with TA were younger (61 ± 13.5 vs 63 ± 14 years), with a similar risk score of the Global Registry of Acute Coronary Events (140 ± 31 vs 143 ± 34) and a shorter median time from symptom onset (245 vs 285 minutes); location of acute myocardial infarction, history of myocardial infarction, PCI, or coronary artery bypass surgery did not differ significantly. Thirty-day mortality was 2.1% versus 2.1% (adjusted p = 0.18), and the rate of 1-year survival was 95.5% versus 94.8%. Using fully adjusted Cox multivariate analysis, hazard ratio for 1-year death was 1.13 (95% confidence interval 0.66 to 1.94). After propensity score matching (480 patients per group), 1-year survival was also similar with both strategies. In a real-world setting of patients admitted with STEMI, the use of TA during primary PCI was not associated with improved 1-year survival.

Adjunctive manual thrombus aspiration during ST-segment elevation myocardial infarction: a meta-analysis of randomized controlled trials

OBJECTIVE

The aim of this study was to synthesize evidence by examining the effects of manual thrombus aspiration on clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 26 randomized controlled trials (RCTs), enrolling 11,780 patients, with 5,869 patients randomized to manual thrombus aspiration and 5,911 patients randomized to conventional percutaneous coronary intervention (PCI), were included in the meta-analysis. Separate clinical outcome analyses were based on different follow-up periods. There were no statistically reductions in the incidences of mortality (risk ratio [RR], 0.86 [95% confidence interval [CI]: 0.73 to 1.02]), reinfarction (RR, 0.62 [CI, 0.31 to 1.32]) or target vessel revascularization (RR, 0.89 [CI, 0.75 to 1.05]) in the manual thrombus aspiration arm at 12 to 24 months of follow-up. The composite major adverse cardiac events (MACEs) outcomes were significantly lower in the manual thrombus aspiration arm over the long-term follow-up (RR, 0.76 [CI, 0.63 to 0.91]). A lower incidence of reinfarction was observed in the hospital to 30 days (RR, 0.59 [CI, 0.37 to 0.92]).

CONCLUSION

The present meta-analysis suggested that there was no evidence that using manual thrombus aspiration in patients with STEMI could provide distinct benefits in long-term clinical outcomes.

Application of Intravascular Ultrasound in the Emergency Diagnosis and Treatment of Patients with ST-Segment Elevation Myocardial Infarction

PURPOSE

This study aimed to examine the application of intravascular ultrasound (IVUS) in ST-segment elevation myocardial infarction (STEMI) patients with high thrombus burden (thrombus grade ≥3) undergoing emergency diagnosis and primary percutaneous coronary intervention.

METHODS

Eighty STEMI patients were enrolled and randomly assigned to the IVUS-guided group (38 patients) or non-IVUS group (42 patients). Stent implantation was performed in non-IVUS group patients. IVUS group patients were further divided into low-risk and high-risk patients on the basis of IVUS evaluation for determining whether stenting should be performed. Major adverse cardiac event (MACE) rates, changes in the left ventricular end-diastolic diameter (LVEDD) and ejection fraction (EF) values, and stent numbers were examined during hospitalization, and follow-up was performed at 1, 3, 6, and 12 months postoperatively.

RESULTS

During hospitalization, there were no significant differences in the MACE rates, LVEDD, and EF values and in the follow-up outcomes at 1, 3, 6, and 12 months postoperatively among the patients in the 2 groups (P > 0.05). A significantly lower number of stents were implanted in the IVUS group than in the non-IVUS group patients (P < 0.05).

CONCLUSION

During the IVUS-guided emergency intervention, enhanced antithrombotic therapy and best medical care for low-risk STEMI patients may be feasible.