Thrombus aspiration before primary angioplasty improves myocardial reperfusion in acute myocardial infarction: the DEAR-MI (Dethrombosis to Enhance Acute Reperfusion in Myocardial Infarction) study

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).

A fresh look at coronary microembolization

Mechanical stress from haemodynamic perturbations or interventional manipulation of epicardial coronary atherosclerotic plaques with inflammatory destabilization can release particulate debris, thrombotic material and soluble substances into the coronary circulation. The physical material obstructs the coronary microcirculation, whereas the soluble substances induce endothelial dysfunction and facilitate vasoconstriction. Coronary microvascular obstruction and dysfunction result in patchy microinfarcts accompanied by an inflammatory reaction, both of which contribute to progressive myocardial contractile dysfunction. In clinical studies, the benefit of protection devices to retrieve atherothrombotic debris during percutaneous coronary interventions has been modest, and the treatment of microembolization has mostly relied on antiplatelet and vasodilator agents. The past 25 years have witnessed a relative proportional increase in non-ST-segment elevation myocardial infarction in the presentation of acute coronary syndromes. An associated increase in the incidence of plaque erosion rather than rupture has also been recognized as a key mechanism in the past decade. We propose that coronary microembolization is a decisive link between plaque erosion at the culprit lesion and the manifestation of non-ST-segment elevation myocardial infarction. In this Review, we characterize the features and mechanisms of coronary microembolization and discuss the clinical trials of drugs and devices for prevention and treatment.

Effect of GP IIb/IIIa inhibitor duration on the clinical prognosis of primary percutaneous coronary intervention in ST-segment elevation myocardial infarction with no-/slow-reflow phenomenon

BACKGROUND

In patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI) accompanied by the no-/slow-reflow phenomenon, the maintenance duration of GP IIb/IIIa inhibitor (GPI) is controversial. We compare the efficacy and safety of short- and long-term GPI infusion in STEMI patients with the no-/slow-reflow phenomenon.

METHODS

From June 2016 to December 2019, we continuously included patients with on-set STEMI who underwent pPCI, accompanied by the no-/slow-reflow, during interventional procedures at Guangdong Provincial People's Hospital and Zhuhai Golden Bay Hospital. The hemorrhage events, heart function, and major adverse cardiovascular events (MACE) were compared between < 24 h and ≥ 24 h GPI duration groups. The Kaplan-Meier curve was used to estimate the 1-year MACE-free survival at different GPI utility times.

RESULTS

In total, 127 patients were divided into two groups based on the duration of tirofiban use (less and more than 24 h). There was no significant difference between two groups in terms of baseline characteristics, plaque condition, and coronary physiological function. The two groups showed similar in-hospital MACE (1 [1.85%] vs. 4 [5.48%], p = 0.394) and 1-year MACE-free survival (log-rank test p = 0.9085). The 1-year MACE remained consistent between the two groups in all subgroups of different risk factors of no-/slow-reflow. There was no significant difference in heart function and in-hospital hemorrhage events (3.7% vs. 1.37%, p = 0.179).

CONCLUSION

In the real world, prolonging the duration of GPI may not significantly improve the clinical outcome in patients with STEMI with no-/slow-reflow.

Controlling Reperfusion Injury With Controlled Reperfusion: Historical Perspectives and New Paradigms

Cardiac reperfusion injury is a well-established outcome following treatment of acute myocardial infarction and other types of ischemic heart conditions. Numerous cardioprotection protocols and therapies have been pursued with success in pre-clinical models. Unfortunately, there has been lack of successful large-scale clinical translation, perhaps in part due to the multiple pathways that reperfusion can contribute to cell death. The search continues for new cardioprotection protocols based on what has been learned from past results. One class of cardioprotection protocols that remain under active investigation is that of controlled reperfusion. This class consists of those approaches that modify, in a controlled manner, the content of the reperfusate or the mechanical properties of the reperfusate (e.g., pressure and flow). This review article first provides a basic overview of the primary pathways to cell death that have the potential to be addressed by various forms of controlled reperfusion, including no-reflow phenomenon, ion imbalances (particularly calcium overload), and oxidative stress. Descriptions of various controlled reperfusion approaches are described, along with summaries of both mechanistic and outcome-oriented studies at the pre-clinical and clinical phases. This review will constrain itself to approaches that modify endogenously-occurring blood components. These approaches include ischemic postconditioning, gentle reperfusion, controlled hypoxic reperfusion, controlled hyperoxic reperfusion, controlled acidotic reperfusion, and controlled ionic reperfusion. This review concludes with a discussion of the limitations of past approaches and how they point to potential directions of investigation for the future.

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.

Outcome of manual thrombus aspiration for patients undergoing primary PCI for acute STEMI showing large thrombus burden

Background

Routine thrombus aspiration during primary PCI does not improve clinical outcomes. Although recent guidelines for management of patient presented by ST-elevation myocardial infarction treated by primary PCI does not recommend routine use of thrombus aspiration and ranking it as class III recommendation. However, there is remaining uncertainty about rule of TA in group of patients presented by STEMI and their initial coronary angiogram shows large thrombus burden as there is a logical rationale for greater benefit, and still, there are no clear guidelines for management of this group of patients; the aim of this study is to evaluate the in-hospital and short-term outcome of using manual thrombus aspiration in STEMI patients undergoing primary PCI and showing large thrombus burden.

Results

The study was prospective observational study included 209 patients referred to coronary care unit (CCU) with diagnosis of STEMI who had undergone primary PCI; their initial coronary angiography show totally occluded infarct-related artery with heavy thrombus burden. Patients were divided into 2 groups: group (B) which included 73 patients, who had undergone PTCA and manual thrombus aspiration followed by stent to culprit lesion, and group (A) which included 136 patients, who had undergone conventional PTCA and stent of culprit lesion within the period from November 2016 till July 2018. Patients had a pre-discharge echo and were followed up for 4 weeks for major adverse cardiac events (MACE) and echo repeated after 1 month of discharge.

It was found that thrombus aspiration in heavy thrombus burden cases had improved in-hospital mortality and in-hospital secondary endpoints (TIMI flow, MBG, ST-segment resolution), as well as 30-day MACE and LV systolic function.

Conclusion

In patients presented with STEMI and heavy thrombus burden culprit artery, manual thrombus aspiration has great value in reducing index hospitalization and 1 month mortality and improve TIMI flow, MBG, ST-segment resolution, and left ventricular systolic function.

Association of Physician Variation in Use of Manual Aspiration Thrombectomy With Outcomes Following Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction: The National Cardiovascular Data Registry CathPCI Registry

Importance

Following negative randomized clinical trials, US guidelines downgraded support for routine manual aspiration thrombectomy (AT) during primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI). However, some PCI operators continue to endorse a clinical benefit with AT use despite the lack of supportive data.

Objective

To examine temporal trends and comparative outcomes of AT use during pPCI for STEMI.

Design, Setting, and Participants

Retrospective cohort study of the National Cardiovascular Data Registry (NCDR) CathPCI Registry from July 1, 2009, to June 30, 2016, to assess temporal trends and in-hospital outcomes associated with AT use. To evaluate outcomes through 180 days, a subanalysis was conducted among Centers for Medicare and Medicaid Services-linked patients from July 1, 2009, through December 31, 2014. The comparative effectiveness analysis was performed using instrumental variable analyses to account for treatment selection bias. The instrumental variable was operator's preference to use AT during pPCI. Data were analyzed between February 1, 2017, and April 1, 2018.

Exposures

Aspiration thrombectomy use during pPCI for STEMI.

Main Outcomes and Measures

Primary outcomes included in-hospital stroke and death. Secondary outcomes included heart failure, stroke, all-cause rehospitalization, and death through 180 days of follow-up.

Results

Among all pPCIs performed (683 584), the mean (SD) age of patients was 61.7 (12.8) years, 489 257 were male (71.6%), and 596 384 were white (87.2%). Among patients undergoing pPCI, AT use increased from 2009 through 2011, with peak use of 13.8%. This was followed by a decline of more than 9%, reaching 4.7% by mid-2016. Overall, AT was used in 10.8% of pPCIs (lowest operator group median, 0%; highest operator group median, 33.8%). After instrumental variable analysis, AT use was associated with no difference in in-hospital death (adjusted absolute risk difference, -0.18%; 95% CI, -0.53% to 0.16%; P = .29) and a small increase in in-hospital stroke (adjusted RD, 0.14%; 95% CI, 0.01%-0.30%; P = .03). Among Centers for Medicare and Medicaid Services-linked patients, AT use was not associated with differences in death, heart failure, stroke, or rehospitalization at 180 days.

Conclusions and Relevance

In this large, nationwide analysis, AT use during STEMI pPCI declined by more than 50% since 2011, with use as of mid-2016 at less than 5%. Selective AT use was associated with a small excess risk of in-hospital stroke and no difference in other outcomes through 180 days of follow-up.

Lancaster G, W. Zarich S. Invasive Evaluation of the Microvasculature in Acute Myocardial Infarction: Coronary Flow Reserve versus the Index of Microcirculatory Resistance

Acute myocardial infarction (AMI) is one of the most common causes of death in both the developed and developing world. It has high associated morbidity despite prompt institution of recommended therapy. The focus over the last few decades in ST-segment elevation AMI has been on timely reperfusion of the epicardial vessel. However, microvascular consequences after reperfusion, such as microvascular obstruction (MVO), are equally reliable predictors of outcome. The attention on the microcirculation has meant that traditional angiographic/anatomic methods are insufficient. We searched PubMed and the Cochrane database for English-language studies published between January 2000 and November 2019 that investigated the use of invasive physiologic tools in AMI. Based on these results, we provide a comprehensive review regarding the role for the invasive evaluation of the microcirculation in AMI, with specific emphasis on coronary flow reserve (CFR) and the index of microcirculatory resistance (IMR).

2019 Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology Guidelines on the Acute Management of ST-Elevation Myocardial Infarction: Focused Update on Regionalization and Reperfusion

Rapid reperfusion of the infarct-related artery is the cornerstone of therapy for the management of acute ST-elevation myocardial infarction (STEMI). Canada's geography presents unique challenges for timely delivery of reperfusion therapy for STEMI patients. The Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology STEMI guideline was developed to provide advice regarding the optimal acute management of STEMI patients irrespective of where they are initially identified: in the field, at a non-percutaneous coronary intervention-capable centre or at a percutaneous coronary intervention-capable centre. We had also planned to evaluate and incorporate sex and gender considerations in the development of our recommendations. Unfortunately, inadequate enrollment of women in randomized trials, lack of publication of main outcomes stratified according to sex, and lack of inclusion of gender as a study variable in the available literature limited the feasibility of such an approach. The Grading Recommendations, Assessment, Development, and Evaluation system was used to develop specific evidence-based recommendations for the early identification of STEMI patients, practical aspects of patient transport, regional reperfusion decision-making, adjunctive prehospital interventions (oxygen, opioids, antiplatelet therapy), and procedural aspects of mechanical reperfusion (access site, thrombectomy, antithrombotic therapy, extent of revascularization). Emphasis is placed on integrating these recommendations as part of an organized regional network of STEMI care and the development of appropriate reperfusion and transportation pathways for any given region. It is anticipated that these guidelines will serve as a practical template to develop systems of care capable of providing optimal treatment for a wide range of STEMI patients.

To Whom Thrombus Aspiration May Concern?

BACKGROUND

Thrombus aspiration for ST-segment elevation myocardial infarction (STEMI) may improve myocardial perfusion. However, these favourable results called into a question by data indicating not only a lack of efficacy but a risk of potentially deleterious complications.

AIM

To assess the effect of thrombus aspiration during the primary percutaneous coronary intervention (PPCI) on procedural angiographic results, stent characteristics, and major adverse cardiac and cerebrovascular events (MACCE).

METHODS

All consecutive STEMI patients candidate for PPCI and admitted to Critical Care Department, Cairo University hospitals, managed either by thrombectomy before primary PCI (if thrombus score ≥ 3) or conventional PPCI, Six hundred seven subjects were enrolled in the study divided into Group with thrombectomy before PPCI (107 subjects, 18%), and group with Conventional PCI (500 subjects, 82%). ST-segment resolution, peak CK-MB, TIMI score, thrombus score, and MBG were assessed; stent number, diameter, length and stented segment were reported and follow up MACCE was reported (in hospital and 1-year post-intervention).

RESULTS

Mean values for peak CKMB were less in thrombectomy group (228 ± 174 I/U vs 269 ± 186 I/U, p = 0.04), ST segment resolution ≥ 70% occurred in {63 subjects (58.9%) vs 233 (46.6%), p = 0.001} in thrombectomy vs conventional group respectively. TIMI score pre procedure was zero in (102 subjects (95%) vs 402 (80.4%), p = 0.001), while TIMI III post procedure was reported in (100 subjects (93.4%) vs 437 (87%), p = 0.06), MBG mean values were (2.4 ± 0.6 vs 2.0 ± 1, p = 0.001), thrombus score was higher in thrombectomy group (4.6 ± 0.4 vs 0.8 ± 1.7, p = 0.001) in thrombectomy vs conventional group respectively. Direct stenting was { 34 patients (31%) vs 102 patients (20%), p = 0.05}, mean stent diameter (2.7 ± 1.3 mm vs 3.5 ± 1.3 mm, p = 0.3), mean stent length was (19.9 mm ± 10 versus 22.7 mm ± 8 in p 0.01). mean stent number was (1.0 ± 0.5 vs 1.2 ± 0.6, p = 0.001), mean stented segment was (22.5 ± 13.5 vs 28.5 ± 15.2 mm, p = 0.001) in thrombectomy vs conventional group respectively. MACCE in hospital were reported in {9 subjects (8.4%) vs 70 (14%), p = 0.07)}. Follow up MACCE after 1 year reported in {6 subjects (5.6 %) vs 80 (16 %), p 0.= 4} in thrombectomy vs conventional group respectively.

CONCLUSION

Thrombus aspiration before primary PCI (in a selected group with thrombus score ≥ 3) improves myocardial perfusion, suggested by better ST-segment resolution, TIMI flow, less peak CKMB and MBG, associated with a higher rate of direct stenting, shorter stent length, stented segments and less number of stents. Although thrombus aspiration was done in more risky patients (higher thrombus score) MACCE (in hospital and 1 year follow up) showed no statistical difference.

Outcome of thrombus aspiration in STEMI patients: a propensity score-adjusted study

The use of thrombus aspiration (TA) prior to primary percutaneous coronary intervention (PPCI) has undergone a radical change in intervention guidelines. The clinical implications, however, are still under scrutiny. This study investigated the clinical effects and outcome of TA before PPCI in patients with ST-segment elevation myocardial infarction (STEMI). Overall 1027 patients with STEMI were analyzed in this retrospective, propensity score-adjusted, multicenter study. The primary endpoints were in-hospital and long-term mortality. There were 418 patients in the TA group and 609 in the conventional PPCI group. The in-hospital mortality rate was significantly higher in the TA group (8.7 vs. 5.0%; P = 0.03). During long-term follow-up [median follow-up duration 689 days (IQR 405-959)] the mortality rates were similar (TA 14.3%, conventional PPCI 15.0%; P = 0.85). Survival analysis for the complete observation period revealed no significant benefit of TA [hazard ratio (HR) 1.12; 97.5% CI 0.90-0.71; P = 0.63]. There were also no significant differences between the groups in the following secondary endpoints: composite of cardiovascular death and non-fatal reinfarction at discharge (P = 0.39), post-PPCI thrombolysis in myocardial infarction flow-grade-3 (P = 0.14), left ventricular ejection fraction (P = 0.47), and non-fatal reinfarction during follow-up (P = 0.17). Rehospitalization rate (1.82 vs. 10.3%; P < 0.0001) and Canadian Cardiovascular Society (CCS) grading (P = 0.02) during follow-up were significantly lower in the TA group. In our cohort the in-hospital mortality rate was significantly higher for TA patients, but during long-term follow-up the mortality rates did not differ. The incidence of rehospitalization and CCS grading were lower in the TA-treated patients.

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.

Effect of thrombus aspiration on angiography and outcome in patients undergoing primary coronary angioplasty

Thrombus exerts a major impact on the performance and outcome of primary and rescue interventions in acute ST-elevation myocardial infarction. Although the optimal treatment of thrombotic lesions is still controversial, thrombus aspiration provides an effective method to achieve successful reperfusion during primary angioplasty. We compared clinical and angiographic outcomes in 286 patients with acute ST-elevation myocardial infarction undergoing primary percutaneous transluminal coronary angioplasty (PTCA) and thrombus aspiration with those who underwent conventional PTCA without thrombus aspiration. Thrombus aspiration during primary percutaneous coronary intervention in patients with high thrombus burden resulted in better Thrombolysis in Myocardial Infarction (TIMI) 3 flow in the infarct-related artery and helped achieve faster ST-segment resolution on the electrocardiogram compared with conventional angioplasty without thrombus aspiration.

Molecular signature of coronary stent thrombosis: oxidative stress and innate immunity cells

The clinical impact of in-stent thrombosis is high because it is associated with high mortality and 20 % of the patients suffer a recurrent event within the two following years. The aim of this study was to characterise the morphologic and proteomic profile of in-stent thrombi (IST) in comparison to thrombi developed on native coronary arteries (CT) to identify a differential molecular signature. The study included 45 patients with ST-elevation-myocardial-infarction (STEMI) treated by primary-percutaneous-intervention and thrombus aspiration: 21 had IST and 24 had CT. Thrombi were characterised by morphologic immunohistochemical analysis and differential proteomic profiling (2-DE+MALDI-TOF/TOF). Bioinformatic analysis revealed differences in proteins related to oxidative-stress and cell death/survival. IST showed a higher content of structural proteins (gelsolin, actin-cytoplasmic-1, tropomyosin, and myosin) together with an imbalance in redox-homeostasis related proteins (increased superoxide-dismutase and decreased peroxiredoxin-2 thrombus content), and a coordinated increase of chaperones (HSP60 and HSC70) and cellular quality control-related proteins (26S–protease-regulatory-subunit-7). These changes were reflected into a significant decrease in HSC70 systemic levels and a significant increase in advanced-oxidation-protein-products (AOPP) indicative of increased oxidative stress-mediated protein damage in IST. Our results reveal an imbalance in redox-related proteins indicative of an exacerbated oxidative-stress that leads to an accumulation of AOPP serum levels in IST. Moreover, the coordinated increase in chaperones and regulatory proteins reflects the activation of intracellular protection mechanisms to maintain protein integrity in IST. The failure to counterbalance the stress situation could trigger cellular apoptosis leading to the destabilization of the thrombus and to a worse prognosis of IST-STEMI-patients.

Supplementary Material to this article is available online at www.thrombosis-online.com.

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.

The role of residual intrastent thrombus during primary angioplasty: insights from the COCTAIL II study

AIMS

Recent frequency-domain optical coherence tomography studies showed that a complete removal of thrombotic materials is rarely achieved after percutaneous coronary interventions for ST segment elevation myocardial infarction. Residual intrastent thrombus can embolize distally leading to microcirculatory injury. The aim was to find a possible correlation between residual intrastent thrombus and angiographic indexes of myocardial reperfusion.

METHODS

The population consisted of 128 ST segment elevation myocardial infarction patients enrolled in the COCTAIL II trial. Intrastent thrombus at optical coherence tomography was defined as the maximum percentage value of thrombus area (thrombus area/stent area × 100 in the cross-section with largest thrombus). A thrombus area of at least 16% (mean value) was considered indicative of high residual intrastent thrombus. The following angiographic indexes of myocardial reperfusion were evaluated: thrombolysis in myocardial infarction (TIMI) value, corrected TIMI frame count and myocardial blush grade.

RESULTS

Angiographic and optical coherence tomography results are available in 119 patients: 64 had a maximum percentage value of thrombus area less than 16%, whereas the remaining 55 had a residual intrastent thrombus at least 16%. No differences were found regarding the microcirculatory indexes at baseline angiogram. After intervention, patients with intrastent thrombus less than 16% showed a significant improvement in the final TIMI value (2.87 ± 0.33 vs 2.67 ± 0.54; P = 0.014), final TIMI frame count (11.71 ± 4.58 vs 18.04 ± 17.32; P = 0.012) and a nonsignificant improvement in the final myocardial blush grade value (2.58 ± 0.58 vs 2.43 ± 0.76; P = 0.255).

CONCLUSION

Data obtained from this ancillary study of the COCTAIL II suggest that the presence of high residual intrastent thrombus in patients undergoing primary angioplasty is associated with worsened final microcirculatory indexes.

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.

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.

Manual Thrombus Aspiration and the Improved Survival of Patients With Unstable Angina Pectoris Treated With Percutaneous Coronary Intervention (30 Months Follow-Up)

The clinical effect of intracoronary thrombus aspiration during percutaneous coronary intervention in patients with unstable angina pectoris is unknown. In this study, we aimed to assess how thrombus aspiration during percutaneous coronary intervention affects in-hospital and 30-month mortality and complications in patients with unstable angina pectoris.We undertook an observational cohort study of 645 consecutive unstable angina pectoris patients who had performed percutaneous coronary intervention from February 2011 to March 2013. Before intervention, 159 patients who had culprit lesion with thrombus were randomly assigned to group 1 (thrombus aspiration group) and group 2 (stand-alone percutaneous coronary intervention group). All patients were followed-up 30 months until August 2015.Thrombus aspiration was performed in 64 patients (46%) whose cardiac markers (ie, creatinine kinase [CK-MB] mass and troponin T) were significantly lower after percutaneous coronary intervention than in those of group 2 (CK-MB mass: 3.80 ± 1.11 vs 4.23 ± 0.89, P = 0.012; troponin T: 0.012 ± 0.014 vs 0.018 ± 0.008, P = 0.002). Left ventricular ejection fraction at 6, 12, and 24 months postintervention was significantly higher in the group 1. During a mean follow-up period of 28.87 ± 6.28 months, mortality rates were 6.3% in the group 1 versus 12.9% in the group 2. Thrombus aspiration was also associated with significantly less long-term mortality in unstable angina pectoris patients (adjusted HR: 4.61, 95% CI: 1.16-18.21, P = 0.029).Thrombus aspiration in the context of unstable angina pectoris is associated with a limited elevation in cardiac enzymes during intervention that minimises microembolization and significantly improves both of epicardial flow and myocardial perfusion, as shown by angiographic TIMI flow grade and frame count. Thrombus aspiration during percutaneous coronary intervention in unstable angina pectoris patients has better survival over a 30-month follow-up period.

Manual Thrombus Aspiration Is Not Associated With Reduced Mortality in Patients Treated With Primary Percutaneous Coronary Intervention: An Observational Study of 10,929 Patients With ST-Segment Elevation Myocardial Infarction From the London Heart Attack Group

OBJECTIVES

This study aimed to assess the impact of thrombus aspiration on mortality in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention (PCI).

BACKGROUND

The clinical effect of routine intracoronary thrombus aspiration before primary PCI in patients with ST-segment elevation myocardial infarction is uncertain.

METHODS

We undertook an observational cohort study of 10,929 ST-segment elevation myocardial infarction patients from January 2005 to July 2011 at 8 centers across London, United Kingdom. Patients' details were recorded at the time of the procedure into local databases using the British Cardiac Intervention Society PCI dataset. Primary outcome was all-cause mortality at a median follow-up of 3.0 years (interquartile range: 1.2 to 4.6 years).

RESULTS

In our cohort, 3,572 patients (32.7%) underwent thrombus aspiration during primary PCI. Patients who had thrombus aspiration were younger, had lower rates of previous myocardial infarction but were more likely to have poor left ventricular function. Procedural success rates were higher (90.9% vs. 89.2%; p=0.005) and in-hospital major adverse cardiac event rates were lower (4.4% vs. 5.5%; p=0.012) in patients undergoing thrombus aspiration. However, Kaplan-Meier analysis demonstrated no significant difference in mortality rates between patients with and without thrombus aspiration (14.8% aspiration vs. 15.3% PCI only; p=0.737) during the follow-up period. After multivariate Cox analysis (hazard ratio [HR]: 0.89, 95% confidence interval [CI]: 0.65 to 1.23) and the addition of propensity matching (HR: 0.85 95% CI: 0.60 to 1.20) thrombus aspiration was still not associated with decreased mortality.

CONCLUSIONS

In this cohort of nearly 11,000 patients, routine thrombus aspiration was not associated with a reduction in long-term mortality in patients undergoing primary PCI, although procedural success and in-hospital major adverse cardiac event rates were improved.

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.

Comparison of Successful Myocardial Reperfusion and Adverse Events in Patients With ST-Elevation Myocardial Infarction Who Underwent Rescue Percutaneous Coronary Intervention After Failed Fibrinolytic Therapy With Versus Without Manual Coronary Thrombus Aspiration

It has been unclear the impact of manual thrombus aspiration (TA) on procedural outcomes in patients with ST-elevation myocardial infarction (STEMI) who underwent rescue percutaneous coronary intervention (PCI) after failed fibrinolytic therapy in comparison with primary PCI. Our aim was to test the hypothesis that manual TA may improve myocardial reperfusion and clinical outcomes in patients with STEMI who underwent rescue PCI after failed fibrinolytic therapy. From March 2011 to March 2014, 70 patients with STEMI after unsuccessful fibrinolysis were randomized to either rescue PCI with TA (TA group) or without TA (NTA group). Primary end points were rate of myocardial blush grade ≥2 and ST-segment resolution ≥70%. The secondary end point included 30 days follow-up for major adverse cardiac events (MACEs). Baseline clinical and angiographic characteristics were similar in the 2 groups. The TA and NTA groups were compared as follows: myocardial blush grade ≥2, 71% versus 46% (p <0.05); complete ST-segment resolution 71% versus 46% (p <0.05); no reflow 20% versus 49% (p <0.05); procedure time (min) 65.0 ± 38.6 versus 90.1 ± 28.8 (p <0.05); contrast amount (ml) 99.0 ± 45.2 versus 121.2 ± 33.4 (p <0.05); and direct stenting 60% versus 37% (p <0.05). There was a significant reduction of MACE in the TA group, 20% versus 37% (p <0.05). In conclusion, rescue PCI with manual TA leads to better myocardial reperfusion and significant reduction of MACE.

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.

Clinical efficacy of thrombus aspiration on 5-year clinical outcomes in patients with ST-segment elevation acute myocardial infarction undergoing percutaneous coronary intervention

Background

Adjunctive thrombus aspiration (TA) during primary percutaneous coronary intervention (PCI) was reported to promote better coronary and myocardial reperfusion. However, long-term mortality benefit of TA remains controversial. The objective of this study is to investigate the clinical impact of TA on long-term clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI.

Methods and Results

The CREDO-Kyoto AMI Registry is a large-scale cohort study of acute myocardial infarction patients undergoing coronary revascularization in 2005–2007 at 26 hospitals in Japan. Among 5429 patients enrolled in the registry, the current study population consisted of 3536 patients who arrived at the hospital within 12 hours after the symptom onset and underwent primary PCI. Clinical outcomes were compared between the 2 patient groups with or without TA. During primary PCI procedures, 2239 out of 3536 (63%) patients underwent TA (TA group). The cumulative 5-year incidence of all-cause death was significantly lower in the TA group than in the non-TA group (18.5% versus 23.9%, log-rank P<0.001). After adjusting for confounders, however, the risk for all-cause death in the TA group was not significantly lower than that in the non-TA group (hazard ratio: 0.90, 95% CI: 0.76 to 1.06, P=0.21). The adjusted risks for cardiac death, myocardial infarction, stroke, and target-lesion revascularization were also not significantly different between the 2 groups.

Conclusions

Adjunctive TA during primary PCI was not associated with better 5-year mortality in STEMI patients.

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.

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.

Does manual thrombus aspiration help optimize stent implantation in ST-segment elevation myocardial infarction?

AIM: To evaluate the impact of thrombus aspiration (TA) on procedural outcomes in a real-world ST-segment elevation myocardial infarction (STEMI) registry.

METHODS: From May 2006 to August 2008, 542 consecutive STEMI patients referred for primary or rescue percutaneous coronary intervention were enrolled and the angiographic results and stent implantation characteristics were compared according to the performance of manual TA.

RESULTS: A total of 456 patients were analyzable and categorized in TA group (156 patients; 34.2%) and non-TA (NTA) group (300 patients; 65.8%). Patients treated with TA had less prevalence of multivessel disease (39.7% vs 54.7%, P = 0.003) and higher prevalence of initial thrombolysis in myocardial infarction flow < 3 (P < 0.001) than NTA group. There was a higher rate of direct stenting (58.7% vs 45.5%, P = 0.009), with shorter (24.1 ± 11.8 mm vs 26.9 ± 15.7 mm, P = 0.038) and larger stents (3.17 ± 0.43 mm vs 2.93 ± 0.44 mm, P < 0.001) in the TA group as compared to NTA group. The number of implanted stents (1.3 ± 0.67 vs 1.5 ± 0.84, P = 0.009) was also lower in TA group.

CONCLUSION: In an “all-comers” STEMI population, the use of TA resulted in more efficient procedure leading to the implantation of less number of stents per lesion of shorter lengths and larger sizes.

Changes in thrombus composition and profilin-1 release in acute myocardial infarction

AIM

Thrombus formation is a dynamic process regulated by flow, blood cells, and plasma proteins. The present study was performed to investigate the characteristics of human coronary thrombus in ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

Patients admitted with ST-elevation myocardial infarction, in which thrombectomy was performed, were included (n = 86). Intracoronary thrombi and blood from the culprit coronary site and the systemic circulation were obtained during percutaneous coronary intervention (PCI). Thrombi were categorized by onset-of-pain-to-PCI elapsed time in thrombus of <3 (T3) and more than 6 h of evolution (T6). Clinical, morphological, and proteomic variables were investigated. While T3 were mainly composed by platelets and fibrin(ogen), T6 were characterized by a reduced platelet content, increased leucocytes infiltration (including monocytes, neutrophils, T-cells, and B-cells), and appearance of undifferentiated progenitor cells. Significant differences between T3 and T6 were found in the cell cytoskeleton-associated proteome (beta-actin and tropomyosin 3 and 4). By discovery proteomics, we have identified profilin-1 (Pfn-1) in the coronary thrombi and detected higher levels in T3 than in T6. While plasma Pfn-1 levels were low in T3 patients, levels significantly increased in both coronary and peripheral circulation in T6 patients indicating release. In vitro platelet aggregation studies showed that platelets secrete Pfn-1 upon complete activation.

CONCLUSION

Coronary thrombi show rapid dynamic changes both in structure and cell composition as a function of elapsed onset-of-pain-to-PCI time. Aged ischaemic thrombi were more likely to have reduced Pfn-1 content releasing Pfn-1 to the circulation. Onset-of-pain-to-PCI elapsed time in STEMI patients and hence age of occlusive thrombus can be profiled by Pfn-1 levels found in the peripheral circulation.

Coronary thrombus in patients undergoing primary PCI for STEMI: Prognostic significance and management

Acute ST-elevation myocardial infarction (STEMI) usually results from coronary atherosclerotic plaque disruption with superimposed thrombus formation. Detection of coronary thrombi is a poor prognostic indicator, which is mostly proportional to their size and composition. Particularly, intracoronary thrombi impair both epicardial blood flow and myocardial perfusion, by occluding major coronary arteries and causing distal embolization, respectively. Thus, although primary percutaneous coronary intervention is the preferred treatement strategy in STEMI setting, the associated use of adjunctive antithrombotic drugs and/or percutaneous thrombectomy is crucial to optimize therapy of STEMI patients, by improving either angiographical and clinical outcomes. This review article will focus on the prognostic significance of intracoronary thrombi and on current antithrombotic pharmacological and interventional strategies used in the setting of STEMI to manage thrombotic lesions.

Aspiration thrombectomy in patients undergoing primary angioplasty: totality of data to 2013

OBJECTIVES

We sought to update our meta-analysis on clinical outcomes with aspiration thrombectomy prior to primary percutaneous coronary intervention (PPCI) compared with conventional PPCI alone due to the availability of additional trial data.

BACKGROUND

The clinical efficacy of adjunctive aspiration thrombectomy in ST-elevation myocardial infarction (STEMI) patients undergoing PPCI remains controversial. A recent large-scale randomized trial showed no benefit in terms of mortality at 30 days.

METHODS

Clinical trials that randomized STEMI patients to aspiration thrombectomy prior to PPCI compared with conventional PPCI alone were included.

RESULTS

A total of 11,321 patients from 20 randomized controlled trials were included. The composite major adverse cardiac event (MACE) endpoint was lower in the aspiration thrombectomy arm compared with conventional PPCI alone (risk ratio [RR] = 0.81, 95% CI 0.70-0.94; P = 0.006). Although all-cause mortality was similar between the adjunctive aspiration thrombectomy arm and PPCI arms (RR = 0.83, 95% CI 0.67-1.01; P = 0.06), late mortality (6-12 months) was significantly reduced (RR = 0.64; 95% CI 0.44-0.92; P = 0.016). Reinfarction (RR = 0.64, 95% CI 0.44-0.92; P = 0.017) and stent thrombosis (RR = 0.54; 95% CI 0.32-0.91; P = 0.021) were similarly lower. Differences in target vessel revascularization were of borderline significance (RR = 0.83, 95% CI 0.68-1.01; P = 0.06).

CONCLUSIONS

Our meta-analysis including all randomized controlled trials on aspiration thrombectomy to date demonstrates a significant reduction in adverse clinical outcomes including stent thrombosis compared with conventional PCI alone.

Angiographic and Clinical Impact of Successful Manual Thrombus Aspiration in Diabetic Patients Undergoing Primary PCI

Background. Diabetes mellitus is associated with worse angiographic and clinical outcomes after percutaneous coronary intervention (PCI). Aim. To investigate the impact of manual thrombus aspiration on in-stent restenosis (ISR) and clinical outcome in patients treated by bare-metal stent (BMS) implantation for ST-segment elevation myocardial infarction (STEMI). Methods. 100 diabetic patients were prospectively enrolled. They were randomly assigned to undergo either standard primary PCI (group A, 50 patients) or PCI with thrombus aspiration using Export catheter (group B, 50 patients). The primary endpoint was the rate of eight-month ISR. The secondary endpoint included follow-up for major adverse cardiac events (MACE). Results. Mean age of the study cohort was 59.86 ± 8.3 years, with 64 (64%) being males. Baseline characteristics did not differ between both groups. Eight-month angiogram showed that group B patients had significantly less late lumen loss (0.17 ± 0.35 versus 0.60 ± 0.42 mm, P < 0.001), with lower incidence of ISR (4% versus 16.6%, P < 0.001). There was a trend towards lower rate of MACE in the same group of patients. Conclusion. In diabetic patients undergoing primary PCI, manual thrombus aspiration (compared with standard PCI) was associated with better ISR rate after BMS implantation.

Use of Thrombectomy Devices in Primary Percutaneous Interventions for ST-elevation Myocardial Infarction - An Update

Primary percutaneous coronary intervention (PPCI) is the preferred reperfusion modality in patients with ST-elevation myocardial infarction (STEMI). While PPCI is highly effective in achieving epicardial coronary reperfusion, a significant proportion of patients fail to achieve adequate myocardial reperfusion. This is in part due to the distal microembolisation of thrombus and plaque debris during PCI. Recognition of this has led to the development of a number of devices with different mechanisms of action that aim to reduce such distal embolisation and therefore improve end myocardial perfusion. Study results of thrombectomy devices however have been largely inconsistent, especially about clinical outcome data, and several meta-analyses have been carried out as a result. This review aims to critically analyse the literature data on thrombectomy during PPCI, taking into account the most recent studies and the latest meta-analyses looking to see whether thrombectomy use is associated with improved outcomes.