Skip main navigation

Is Aspiration Thrombectomy Beneficial in Patients Undergoing Primary Percutaneous Coronary Intervention?

Meta-Analysis of Randomized Trials
Originally publishedhttps://doi.org/10.1161/CIRCINTERVENTIONS.114.002258Circulation: Cardiovascular Interventions. 2015;8:e002258

    Abstract

    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.

    Suboptimal coronary reperfusion in patients with ST-segment–elevation myocardial infarction (STEMI) is associated with worse outcomes.1,2 Aspiration thrombectomy has been available as an adjunctive therapy to aid in the restoration of coronary blood flow at the epicardial and microvascular levels. An earlier meta-analysis had suggested that aspiration thrombectomy at the time of primary percutaneous coronary intervention (PCI) was associated with better outcomes3; however, recent randomized trials demonstrated the lack of clinical benefits with routine aspiration thrombectomy.4,5 Furthermore, some studies suggested that this adjunctive technology might be associated with an increased risk of stroke.3,4,6

    Earlier studies suggested that intravenous glycoprotein IIb/IIIa inhibitors administration was associated with improved outcomes in STEMI patients undergoing primary PCI.7 However, studies conducted in the current era of potent ADP antagonists demonstrated lack of clear clinical outcome benefit with glycoprotein IIb/IIIa inhibitors usage.810 A previous retrospective study had suggested that the combination of intravenous glycoprotein IIb/IIIa inhibitors with adjunctive aspiration thrombectomy had better clinical outcomes than either treatment modality separately.11 In the randomized trials evaluating clinical outcomes with aspiration thrombectomy, the usage of glycoprotein IIb/IIIa inhibitors has been variable which could have modified any association between aspiration thrombectomy and adverse cardiovascular outcomes.4,5,1214 In addition, in these trials there was variation in ischemic time, which might also affect any clinical benefit from aspiration thrombectomy.15,16

    In this study, we aimed to conduct a comprehensive meta-analysis to evaluate the outcomes associated with aspiration thrombectomy with the totality of data. Moreover, we sought to explore the effect of coadministration of intravenous glycoprotein IIb/IIIa inhibitors as well as ischemic time on any potential benefits observed with aspiration thrombectomy in STEMI patients undergoing primary PCI.

    Methods

    Data Sources

    A computerized search of the Medline, Web of Science, and the Cochrane databases was conducted without language restriction from inception until April 2015 using the Medical Subject Heading and the key word search terms illustrated in Figure I in the Data Supplement. To ensure that no potentially important studies were missed, the reference lists from the retrieved articles and prior meta-analyses were also checked.3,1721 We communicated with select authors when further article clarification was necessary.

    Selection Criteria

    We selected trials that randomized patients presenting with STEMI within 12 hours of symptom onset to aspiration thrombectomy before PCI versus conventional PCI. Eligible trials were published studies that reported clinical outcome data. Because we planned to explore the effects of glycoprotein IIb/IIIa inhibitors as an effect modifier, we required that the trials reported the percentage of glycoprotein IIb/IIIa inhibitors usage even if the reported percentage of glycoprotein IIb/IIIa inhibitors usage was zero.

    Outcomes and Definitions

    The outcomes that were assessed in this analysis included all-cause mortality, reinfarction, the combined outcome of mortality or reinfarction, major adverse cardiac events (MACEs), stent thrombosis, stroke, and myocardial reperfusion markers (ie, complete ST-segment resolution, and Thrombolysis In Myocardial Infarction (TIMI) blush grade). If the study did not specifically report a definition for MACE, we defined it as the composite of all-cause mortality, reinfarction, or urgent target vessel revascularization. If the individual study reported outcomes at variable follow-up duration, we used the earliest reported follow-up to maximize homogeneity among follow-up duration. Studies that reported outcomes at hospital discharge were assumed to have a follow-up duration of 3 days.

    Statistical Analysis

    This analysis was conducted in concordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.22 We tabulated the number of events that occurred in the treatment arms of each study. Random effects summary risk ratio (RR) were constructed using a DerSimonian-Laird model.23 If there were zero events in a treatment arm, 0.5 was added to each cell. A study with zero events in both treatment arms was excluded. Statistical heterogeneity was assessed for each outcome using the I2 statistic. I2 statistic values <25%, 25% to 50%, and >50% were considered as low, moderate, and high degree of heterogeneity, respectively.24 To account for the possibility of a variable treatment effect with a longer follow-up time, a planned subgroup analysis for all-cause mortality was conducted for the trials that reported mortality at both 1 and 12 months. Random effects meta-regression for the logarithm for RR for each outcome and the average percentage of glycoprotein IIb/IIIa inhibitors usage between both arms, as well as ischemic time, were constructed.25 A study with zero events in a treatment arm was excluded from meta-regression. All P values were 2-tailed, with statistical significance set at 0.05. The statistical analysis was performed using STATA software version 11 (STATA Corporation; College Station, TX).

    Results

    Included Studies

    Seventeen trials with 20 960 patients were available for the analysis.4,5,1215,2637 The weighted mean follow-up duration was 3.7±2.7 months. Three trials reported outcomes at both 1 and 12 months.5,12,14,3840 The mean time between the onset of symptoms to primary PCI was similar in both groups (4.5±1.5 hours; P=0.86). Five trials defined MACE as the composite of death, reinfarction, stroke, or target vessel revascularization.12,3234,37 MACE was defined in 5 studies as death, reinfarction, or target vessel revascularization.14,15,26,27,31 In 1 study, death, reinfarction, or stroke was used as the MACE definition,36 whereas another study used death, reinfarction, or hospitalization for heart failure as the MACE definition.35 Another study defined MACE as composite of death from cardiovascular causes, reinfarction, cardiogenic shock, or New York Heart Association class IV heart failure.4 The remaining 4 studies did not specifically define MACE.5,2830 All the studies that reported complete ST-segment resolution used the cutoff ≥70%,4,1214,26,2831,3437 except for 1 study that used ≥50%.32 Seven studies defined successful reperfusion as TIMI blush grade of 3,13,14,26,29,32,34,35 whereas 5 studies used TIMI blush grade of ≥2.12,28,30,31,37 In Table 1, we summarize the baseline characteristics, the primary outcome, and the follow-up duration of the included studies, whereas Table 2 reports the study medications.

    Table 1. Baseline Characteristics, Follow-Up Duration, and the Primary Outcome of the Included Studies

    Study (Reference)YearPatients (n)Follow-Up Duration, moMean Time From Symptom Onset Till PCI, hPrimary Outcome
    TOTAL420155033/503063.0/2.9*Composite of cardiac death, recurrent MI, cardiogenic shock, class IV heart failure
    TASTE520133621/362313.1/3.0*All-cause mortality
    TROFI26201371/70HospitalizationNR/NRMyocardial reperfusion markers
    MUSTELA27201250/104123.8/3.5*Myocardial reperfusion markers and infarct size
    INFUSE-AMI122012229/22312.4/2.7*Infarct size by MRI
    Ciszewski et al28201167/70Hospitalization5.6/5.6Myocardial reperfusion markers
    PIHRATE292010100/966NR/NRMyocardial reperfusion markers
    Liistro et al30200955/5663.2/3.5Myocardial reperfusion markers
    EXPIRA31200988/8796.2/6.1Myocardial reperfusion markers
    VAMPIRE132008180/175Hospitalization6.3/7.1Myocardial reperfusion markers
    Export322008120/12916.0/5.1Myocardial reperfusion markers
    Chao et al33200837/3765.6/5.9Myocardial reperfusion markers
    TAPAS142008535/53613.2/3.1*Myocardial reperfusion markers
    DEAR-MI34200674/74Hospitalization3.4/3.3Myocardial reperfusion markers
    De Luca et al35200638/3867.2/7.6Left ventricular remodeling
    Kaltoft et al362006108/10714.0/3.5*Myocardial salvage by SPECT
    REMEDIA37200550/4914.6/5.0Myocardial reperfusion markers

    Data are reported as aspiration thrombectomy and PCI/conventional PCI. DEAR-MI indicates Dethrombosis to Enhance Acute Reperfusion in Myocardial Infarction; EXPIRA, Thrombectomy With Export Catheter in Infarct-Related Artery During Primary Percutaneous Coronary Intervention; INFUSE-AMI, Infuse–Acute Myocardial Infarction; MRI, magnetic resonance imaging; MUSTELA, Multidevice Thrombectomy in Acute ST-Segment Elevation Acute Myocardial Infarction; NR, not reported; PCI, percutaneous coronary intervention; PIHRATE, Polish-Italian-Hungarian Randomized Thrombectomy; REMEDIA, The Randomized Evaluation of the Effect of Mechanical Reduction of Distal Embolization by Thrombus-Aspiration in Primary and Rescue Angioplasty; SPECT, single photon emission computed tomography; TAPAS, Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction Study; TASTE, Thrombus Aspiration in Myocardial Infarction; TOTAL, Trial of Routine Aspiration Thrombectomy With PCI Versus PCI Alone in Patients With STEMI; TROFI, Randomized Study to Assess the Effect of Thrombus Aspiration on Flow Area in STEMI Patients; and VAMPIRE, Vacuum Aspiration Thrombus Removal.

    *Median was reported.

    Table 2. Study Medications

    Trial (Reference)ADP Antagonist,%Type of ADP AntagonistGlycoprotein IIb/IIIa Inhibitor, %Glycoprotein IIb/IIIa Inhibitor
    Clopidogrel, %Ticlopidine, %Prasugrel, %Ticagrelor, %TypeRouteDoseTime of Administration
    TOTAL492/9264/640.5/0.510/1117/1737/41NRNRNRNR
    TASTE5NR/NR66/66*NR/NR16/1529/2815/17NRNRNRNR
    TROFI26100/10084/911/015/90/048/63NRNRNRNR
    MUSTELA27100/100100/1000/00/00/0100/100AbciximabIntravenousLD: 0.25 mg/kg followed by 0.125 μg/kg per minute for 12 hBefore the procedure
    INFUSE-AMI12100/10066NR/NR32NR/NR51/50AbciximabLocally at the infarct site0.25 mg/kgDuring the procedure
    Ciszewski et al28100/100100/1000/00/00/084/80AbciximabNRNRNR
    PIHRATE29100/100100/1000/00/00/08/11NRNRNRNR
    Liistro et al30100/100100/1000/00/00/0100/100AbciximabIntravenousLD: 0.25 mg/kg followed by 0.125 μg/kg per minute for 12 hBefore the procedure
    EXPIRA31100/100100/1000/00/00/0100/100AbciximabIntravenousLD: 0.25 mg/kg followed by 0.125 μg/kg per minute for 12 hBefore the procedure
    VAMPIRE13100/1000/0100/1000/00/00/0NANANANA
    Export32NR/NRNR/NRNR/NRNR/NRNR/NR4/14NRNRNRNR
    Chao et al33100/100100/1000/00/00/019/32NRNRNRNR
    TAPAS14100/100100/1000/00/00/093/90AbciximabNRNRNR
    DEAR-MI34NR/NRNR/NRNR/NRNR/NRNR/NR100/100AbciximabIntravenousNRBefore the procedure
    De Luca et al35100/100*NR/NRNR/NRNR/NRNR/NR100/100AbciximabIntravenousLD: 0.25 mg/kg followed by 0.125 μg/kg per minute for 12 hBefore the procedure
    Kaltoft et al36100/100100/100NR/NRNR/NRNR/NR96/93AbciximabNRNRDuring the procedure
    REMEDIA37100/100100/100NR/NRNR/NRNR/NR68/63AbciximabIntravenousLD: 0.25 mg/kg followed by 0.125 μg/kg per minute for 12 hBefore the procedure

    Data are reported as aspiration thrombectomy and PCI/conventional PCI. DEAR-MI indicates Dethrombosis to Enhance Acute Reperfusion in Myocardial Infarction; EXPIRA, Thrombectomy With Export Catheter in Infarct-Related Artery During Primary Percutaneous Coronary Intervention; INFUSE-AMI, Infuse–Acute Myocardial Infarction; LD, loading dose; MUSTELA, Multidevice Thrombectomy in Acute ST-Segment Elevation Acute Myocardial Infarction; NA, not applicable; NR, not reported; PCI, percutaneous coronary intervention; PIHRATE, Polish-Italian-Hungarian Randomized Thrombectomy; REMEDIA, The Randomized Evaluation of the Effect of Mechanical Reduction of Distal Embolization by Thrombus-Aspiration in Primary and Rescue Angioplasty; TAPAS, Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction Study; TASTE, Thrombus Aspiration in Myocardial Infarction; TOTAL, Trial of Routine Aspiration Thrombectomy With PCI Versus PCI Alone in Patients With STEMI; TROFI, Randomized Study to Assess the Effect of Thrombus Aspiration on Flow Area in STEMI Patients; and VAMPIRE, Vacuum Aspiration Thrombus Removal.

    *Reported as the combination of both clopidogrel and ticlopidine.

    Continuous infusion after the procedure was allowed in cases of intraprocedural thrombotic complications.

    Outcomes

    The incidence of all-cause mortality was 2.8% with aspiration thrombectomy versus 3.2% with conventional PCI (RR, 0.89; 95% confidence interval [CI], 0.76–1.04; P=0.13; I2=0%). On subgroup analysis, the risk of all-cause mortality was similar at 1 month (RR, 0.86; 95% CI, 0.61–1.20; P=0.36) and at 12 months (RR, 0.82; 95% CI, 0.61–1.09; P=0.17). The incidence of reinfarction was 1.3% with aspiration thrombectomy versus 1.4% with conventional PCI (RR, 0.93; 95% CI, 0.73–1.17; P=0.52; I2=0%). The incidence of the combined outcome of mortality or reinfarction was 4.1% with aspiration thrombectomy versus 4.6% with conventional PCI (RR, 0.90; 95% CI, 0.79–1.02; P=0.11; I2=0%). The incidence of MACE was 6.0% with aspiration thrombectomy versus 6.6% with conventional PCI (RR, 0.90; 95% CI, 0.81–1.00; P=0.06; I2=0%). Figure 1 shows the forest plot for all-cause mortality, reinfarction, the combined outcome of mortality or reinfarction, and MACE. The incidence of stent thrombosis was 0.9% with aspiration thrombectomy versus 1.2% with conventional PCI (RR, 0.82; 95% CI, 0.62–1.08; P=0.15; I2=0%; Figure II in the Data Supplement). 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; I2=0%; Figure III in the Data Supplement). Aspiration thrombectomy was associated with a higher incidence of complete ST-segment resolution 68% versus 64% (RR, 1.17; 95% CI, 1.08–1.28; P<0.0001; I2=66%), and improved myocardial blush grade of ≥2 59% versus 43% (RR, 1.39; 95% CI, 1.19–1.62; P<0.0001; I2=84%).

    Figure 1.

    Figure 1. Summary plot for all-cause mortality, reinfarction, the combined outcome of mortality or reinfarction, and major adverse cardiac events (MACEs). The relative size of the data markers indicates the weight of the sample size from each study. CI indicates confidence interval; DEAR-MI, Dethrombosis to Enhance Acute Reperfusion in Myocardial Infarction; EXPIRA, Thrombectomy With Export Catheter in Infarct-Related Artery During Primary Percutaneous Coronary Intervention; INFUSE-AMI, Infuse–Acute Myocardial Infarction; MI, myocardial Infarction; MUSTELA, Multidevice Thrombectomy in Acute ST-Segment Elevation Acute Myocardial Infarction; PCI, percutaneous coronary intervention; PIHRATE, Polish-Italian-Hungarian Randomized Thrombectomy; REMEDIA, The Randomized Evaluation of the Effect of Mechanical Reduction of Distal Embolization by Thrombus-Aspiration in Primary and Rescue Angioplasty; RR, risk ratio; TAPAS, Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction Study; TASTE, Thrombus Aspiration in Myocardial Infarction; TOTAL, Trial of Routine Aspiration Thrombectomy With PCI Versus PCI Alone in Patients With STEMI; TROFI, Randomized Study to Assess the Effect of Thrombus Aspiration on Flow Area in STEMI Patients; and VAMPIRE, Vacuum Aspiration Thrombus Removal.

    Meta-Regression

    Meta-regression analysis did not identify a difference for the log RR of all-cause mortality, reinfarction, the combined outcome of mortality or reinfarction, MACE, complete ST-segment resolution, or TIMI blush grade of ≥2 with the percentage of the glycoprotein IIb/IIIa inhibitors usage (P=0.17, 0.70, 0.58, 0.77, 0.17, and 0.98, respectively). Figures 2 and 3 demonstrate the meta-regression plot for mortality and the combined outcome of mortality or reinfarction with the percentage of the glycoprotein IIb/IIIa inhibitors usage. Figures IV and V in the Data Supplement demonstrate the meta-regression plot for the reinfarction and MACE with the percentage of the glycoprotein IIb/IIIa inhibitors usage. We were not able to conduct a separate meta-regression analysis using the difference in the percentage of glycoprotein IIb/IIIa inhibitors between treatment arms because only 3 trials exhibited a modest difference in the percentage of glycoprotein IIb/IIIa inhibitors usage between arms.26,32,33 Similarly, meta-regression analysis did not identify a difference for the log RR of all-cause mortality, reinfarction, the combined outcome of mortality or reinfarction, MACE, complete ST-segment resolution, and TIMI blush grade of ≥2 with ischemic time (P=0.29, 0.66, 0.58, 0.16, 0.20, and 0.25, respectively). Figures 4 and 5 demonstrate the meta-regression plot for mortality and the combined outcome of mortality or reinfarction with ischemic time. Figures VI and VII in the Data Supplement demonstrate the meta-regression plot for the reinfarction and MACE with ischemic time. Meta-regression for the outcomes of stent thrombosis and stroke was not possible because of limited studies available for analysis (several studies were excluded with zero events in a single arm). A separate meta-regression for second generation drug-eluting stents with the individual outcomes also could not be performed because of the limited number of studies reporting this information.

    Figure 2.

    Figure 2. Meta-regression plot for all-cause mortality with the percentage of the glycoprotein IIb/IIIa usage. Plot of logarithm of the risk ratio (RR) of all-cause mortality ( y axis) and the percentage of glycoprotein IIb/IIIa inhibitors usage (x axis).

    Figure 3.

    Figure 3. Meta-regression plot for the combined outcome of mortality or reinfarction with the percentage of the glycoprotein IIb/IIIa usage. Plot of logarithm of the risk ratio (RR) of the combined outcome of mortality or reinfarction on ( y axis) and the percentage of glycoprotein IIb/IIIa inhibitors usage (x axis).

    Figure 4.

    Figure 4. Meta-regression plot for all-cause mortality with ischemic time. Plot of logarithm of the risk ratio (RR) of all-cause mortality ( y axis) and ischemic time (x axis).

    Figure 5.

    Figure 5. Meta-regression plot for the combined outcome of mortality or reinfarction with ischemic time. Plot of logarithm of the risk ratio (RR) of the combined outcome of mortality or reinfarction ( y axis) and ischemic time (x axis).

    Discussion

    In this analysis of 17 randomized trials, we demonstrated that aspiration thrombectomy did not significantly reduce the risk of all-cause mortality, reinfarction, the combined outcome of mortality or reinfarction, MACE, or stent thrombosis when compared with conventional PCI. In addition, aspiration thrombectomy was associated with a nonsignificant increase in the risk of stroke. Moreover, the concomitant administration of intravenous glycoprotein IIb/IIIa inhibitors or ischemic time did not influence (ie, reduce) the risk of mortality, reinfarction, the combined outcomes of mortality or reinfarction, MACE, or myocardial reperfusion markers in STEMI patients who underwent aspiration thrombectomy before primary PCI. We performed a meta-regression to examine the relationship between intravenous glycoprotein IIb/IIIa inhibitors and the different clinical outcomes. Despite the absence of heterogeneity in clinical outcomes, there was a high degree of variability in the percentage of glycoprotein IIb/IIIa inhibitors usage across the trials.41 In the majority of the included studies, patients were pretreated with ADP antagonists and in particular clopidogrel. Our findings were limited to intravenous administration of abciximab, except for the Infuse–Acute Myocardial Infarction (INFUSE-AMI) trial, in which abciximab was administered via an intralesional route by perfusion balloon.

    Prior randomized trials and meta-analyses had shown disparate results for the short-term benefits of aspiration thrombectomy35,17–21; however, none of the studies was designed to address the potential synergistic effect of glycoprotein IIb/IIIa inhibitors on outcomes. In the INFUSE-AMI trial, patients were randomized in a 2×2 factorial design to intralesional abciximab at the site of the infarct lesion using a special infusion catheter versus no intracoronary abciximab. Patients were also simultaneously randomized to aspiration thrombectomy versus no aspiration thrombectomy. Major adverse cardiac and cerebrovascular events at 1 year were numerically lowest (6.8%) in the group that received intralesional abciximab and thrombectomy, when compared with 8.5% with aspiration thrombectomy alone, 9.3% with intralesional abciximab alone, and 11.2% with neither; however, these differences did not achieve statistical significance (P=0.71).39 A recent study demonstrated that concomitant use of glycoprotein IIb/IIIa inhibitors may have a synergistic effect with aspiration thrombectomy on 30-day mortality.42 However, that analysis did not include the totality of data. Also, in our meta-regression analysis, we tested our hypothesis against various outcomes and we sought to eliminate potential bias by excluding studies that had zero events in a single arm. The overall results of this meta-analysis differ from prior meta-analyses likely because of the inclusion of a much larger number of patients and events, as well as a greater number of sites and operators, making the results more generalizable. It is not uncommon for initial favorable effects of experimental treatments to be overestimated. It is also possible that concurrent advances in door-to-balloon time and stent technology have reduced thrombotic complications of primary PCI.

    Our study has some limitations. First, the primary outcome for the majority of the included studies was myocardial reperfusion markers and not clinical outcomes. Second, MACE was not uniformly defined among all the studies; however, we also observed no benefit in the outcome of mortality or myocardial infarction. Third, a few studies were excluded in the meta-regression because of no events. Fourth, benefits such as ability to perform direct stenting or reduced stent length were not examined, as we focused on clinical end points.

    In conclusion, aspiration thrombectomy before primary PCI was not associated with any clinical benefit and might increase the risk of stroke. Moreover, the coadministration of intravenous glycoprotein IIb/IIIa inhibitors and ischemic time did not seem to influence any potential benefits observed with aspiration thrombectomy.

    Footnotes

    The Data Supplement is available at http://circinterventions.ahajournals.org/lookup/suppl/doi:10.1161/CIRCINTERVENTIONS.114.002258/-/DC1.

    Correspondence to Anthony A. Bavry, MD, MPH, North Florida/South Georgia Veterans Health System (Malcom Randall Veterans Administration Medical Center), Medical Service, Cardiology Section (111D), 1601 SW Archer Rd, Gainesville, FL 32608. E-mail

    References

    • 1. van ‘t Hof AW, Liem A, Suryapranata H, Hoorntje JC, de Boer MJ, Zijlstra F.Angiographic assessment of myocardial reperfusion in patients treated with primary angioplasty for acute myocardial infarction: myocardial blush grade.Zwolle Myocardial Infarction Study Group. Circulation. 1998; 97:2302–2306.LinkGoogle Scholar
    • 2. van ‘t Hof AW, Liem A, de Boer MJ, Zijlstra F.Clinical value of 12-lead electrocardiogram after successful reperfusion therapy for acute myocardial infarction.Zwolle Myocardial infarction Study Group. Lancet. 1997; 350:615–619.CrossrefMedlineGoogle Scholar
    • 3. Bavry AA, Kumbhani DJ, Bhatt DL.Role of adjunctive thrombectomy and embolic protection devices in acute myocardial infarction: a comprehensive meta-analysis of randomized trials.Eur Heart J. 2008; 29:2989–3001.CrossrefMedlineGoogle Scholar
    • 4. Jolly SS, Cairns JA, Yusuf S, Meeks B, Pogue J, Rokoss MJ, Kedev S, Thabane L, Stankovic G, Moreno R, Gershlick A, Chowdhary S, Lavi S, Niemelä K, Steg PG, Bernat I, Xu Y, Cantor WJ, Overgaard CB, Naber CK, Cheema AN, Welsh RC, Bertrand OF, Avezum A, Bhindi R, Pancholy S, Rao SV, Natarajan MK, ten Berg JM, Shestakovska O, Gao P, Widimsky P, Džavík V; TOTAL Investigators. Randomized trial of primary PCI with or without routine manual thrombectomy.N Engl J Med. 2015; 372:1389–1398. doi: 10.1056/NEJMoa1415098.CrossrefMedlineGoogle Scholar
    • 5. Fröbert O, Lagerqvist B, Olivecrona GK, Omerovic E, Gudnason T, Maeng M, Aasa M, Angerås O, Calais F, Danielewicz M, Erlinge D, Hellsten L, Jensen U, Johansson AC, Kåregren A, Nilsson J, Robertson L, Sandhall L, Sjögren I, Ostlund O, Harnek J, James SK; TASTE Trial. Thrombus aspiration during ST-segment elevation myocardial infarction.N Engl J Med. 2013; 369:1587–1597. doi: 10.1056/NEJMoa1308789.CrossrefMedlineGoogle Scholar
    • 6. Tamhane UU, Chetcuti S, Hameed I, Grossman PM, Moscucci M, Gurm HS.Safety and efficacy of thrombectomy in patients undergoing primary percutaneous coronary intervention for acute ST elevation MI: a meta-analysis of randomized controlled trials.BMC Cardiovasc Disord. 2010; 10:10. doi: 10.1186/1471-2261-10-10.CrossrefMedlineGoogle Scholar
    • 7. Montalescot G, Barragan P, Wittenberg O, Ecollan P, Elhadad S, Villain P, Boulenc JM, Morice MC, Maillard L, Pansiéri M, Choussat R, Pinton P; ADMIRAL Investigators. Abciximab before Direct Angioplasty and Stenting in Myocardial Infarction Regarding Acute and Long-Term Follow-up. Platelet glycoprotein IIb/IIIa inhibition with coronary stenting for acute myocardial infarction.N Engl J Med. 2001; 344:1895–1903. doi: 10.1056/NEJM200106213442503.CrossrefMedlineGoogle Scholar
    • 8. Le May MR, Wells GA, Glover CA, So DY, Froeschl M, Marquis JF, O’Brien ER, Turek M, Thomas A, Kass M, Jadhav S, Labinaz M.Primary percutaneous coronary angioplasty with and without eptifibatide in ST-segment elevation myocardial infarction: a safety and efficacy study of integrilin-facilitated versus primary percutaneous coronary intervention in ST-segment elevation myocardial infarction (ASSIST).Circ Cardiovasc Interv. 2009; 2:330–338. doi: 10.1161/CIRCINTERVENTIONS.108.847582.108.847582.LinkGoogle Scholar
    • 9. Mehilli J, Kastrati A, Schulz S, Früngel S, Nekolla SG, Moshage W, Dotzer F, Huber K, Pache J, Dirschinger J, Seyfarth M, Martinoff S, Schwaiger M, Schömig A; Bavarian Reperfusion Alternatives Evaluation-3 (BRAVE-3) Study Investigators. Abciximab in patients with acute ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention after clopidogrel loading: a randomized double-blind trial.Circulation. 2009; 119:1933–1940. doi: 10.1161/CIRCULATIONAHA.108.818617.LinkGoogle Scholar
    • 10. De Luca G, Navarese E, Marino P.Risk profile and benefits from Gp IIb-IIIa inhibitors among patients with ST-segment elevation myocardial infarction treated with primary angioplasty: a meta-regression analysis of randomized trials.Eur Heart J. 2009; 30:2705–2713. doi: 10.1093/eurheartj/ehp118.CrossrefMedlineGoogle Scholar
    • 11. Pyxaras SA, Mangiacapra F, Verhamme K, Di Serafino L, De Vroey F, Toth G, Perkan A, Salvi A, Bartunek J, De Bruyne B, Wijns W, Sinagra G, Barbato E.Synergistic effect of thrombus aspiration and abciximab in primary percutaneous coronary intervention.Catheter Cardiovasc Interv. 2013; 82:604–611. doi: 10.1002/ccd.24837.CrossrefMedlineGoogle Scholar
    • 12. Stone GW, Maehara A, Witzenbichler B, Godlewski J, Parise H, Dambrink JH, Ochala A, Carlton TW, Cristea E, Wolff SD, Brener SJ, Chowdhary S, El-Omar M, Neunteufl T, Metzger DC, Karwoski T, Dizon JM, Mehran R, Gibson CM; INFUSE-AMI Investigators. Intracoronary abciximab and aspiration thrombectomy in patients with large anterior myocardial infarction: the INFUSE-AMI randomized trial.JAMA. 2012; 307:1817–1826. doi: 10.1001/jama.2012.421.CrossrefMedlineGoogle Scholar
    • 13. Ikari Y, Sakurada M, Kozuma K, Kawano S, Katsuki T, Kimura K, Suzuki T, Yamashita T, Takizawa A, Misumi K, Hashimoto H, Isshiki T; VAMPIRE Investigators. Upfront thrombus aspiration in primary coronary intervention for patients with ST-segment elevation acute myocardial infarction: report of the VAMPIRE (VAcuuM asPIration thrombus REmoval) trial.JACC Cardiovasc Interv. 2008; 1:424–431. doi: 10.1016/j.jcin.2008.06.004.CrossrefMedlineGoogle Scholar
    • 14. Svilaas T, Vlaar PJ, van der Horst IC, Diercks GF, de Smet BJ, van den Heuvel AF, Anthonio RL, Jessurun GA, Tan ES, Suurmeijer AJ, Zijlstra F.Thrombus aspiration during primary percutaneous coronary intervention.N Engl J Med. 2008; 358:557–567. doi: 10.1056/NEJMoa0706416.CrossrefMedlineGoogle Scholar
    • 15. Balan P, Anderson HV.Aspiration thrombectomy: it’s about time.J Am Coll Cardiol. 2013; 62:1419–1420. doi: 10.1016/j.jacc.2013.03.069.CrossrefMedlineGoogle Scholar
    • 16. Denktas AE, Anderson HV, McCarthy J, Smalling RW.Total ischemic time: the correct focus of attention for optimal ST-segment elevation myocardial infarction care.JACC Cardiovasc Interv. 2011; 4:599–604. doi: 10.1016/j.jcin.2011.02.012.CrossrefMedlineGoogle Scholar
    • 17. Deng SB, Wang J, Xiao J, Wu L, Jing XD, Yan YL, Du JL, Liu YJ, She Q.Adjunctive manual thrombus aspiration during ST-segment elevation myocardial infarction: a meta-analysis of randomized controlled trials.PLoS One. 2014; 9:e113481. doi: 10.1371/journal.pone.0113481.CrossrefMedlineGoogle Scholar
    • 18. Kumbhani DJ, Bavry AA, Desai MY, Bangalore S, Byrne RA, Jneid H, Bhatt DL.Aspiration thrombectomy in patients undergoing primary angioplasty: totality of data to 2013.Catheter Cardiovasc Interv. 2014; 84:973–977. doi: 10.1002/ccd.25532.CrossrefMedlineGoogle Scholar
    • 19. Kumbhani DJ, Bavry AA, Desai MY, Bangalore S, Bhatt DL.Role of aspiration and mechanical thrombectomy in patients with acute myocardial infarction undergoing primary angioplasty: an updated meta-analysis of randomized trials.J Am Coll Cardiol. 2013; 62:1409–1418. doi: 10.1016/j.jacc.2013.04.025.CrossrefMedlineGoogle Scholar
    • 20. De Luca G, Navarese EP, Suryapranata H.A meta-analytic overview of thrombectomy during primary angioplasty.Int J Cardiol. 2013; 166:606–612. doi: 10.1016/j.ijcard.2011.11.102.CrossrefMedlineGoogle Scholar
    • 21. Mongeon FP, Bélisle P, Joseph L, Eisenberg MJ, Rinfret S.Adjunctive thrombectomy for acute myocardial infarction: A bayesian meta-analysis.Circ Cardiovasc Interv. 2010; 3:6–16. doi: 10.1161/CIRCINTERVENTIONS.109.904037.LinkGoogle Scholar
    • 22. Moher D, Liberati A, Tetzlaff J, Altman DG; PRISMA Group. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement.BMJ. 2009; 339:b2535.CrossrefMedlineGoogle Scholar
    • 23. DerSimonian R, Laird N.Meta-analysis in clinical trials.Control Clin Trials. 1986; 7:177–188.CrossrefMedlineGoogle Scholar
    • 24. Higgins JP, Thompson SG, Deeks JJ, Altman DG.Measuring inconsistency in meta-analyses.BMJ. 2003; 327:557–560. doi: 10.1136/bmj.327.7414.557.CrossrefMedlineGoogle Scholar
    • 25. Thompson SG, Higgins JP.How should meta-regression analyses be undertaken and interpreted?Stat Med. 2002; 21:1559–1573. doi: 10.1002/sim.1187.CrossrefMedlineGoogle Scholar
    • 26. Onuma Y, Thuesen L, van Geuns RJ, van der Ent M, Desch S, Fajadet J, Christiansen E, Smits P, Holm NR, Regar E, van Mieghem N, Borovicanin V, Paunovic D, Senshu K, van Es GA, Muramatsu T, Lee IS, Schuler G, Zijlstra F, Garcia-Garcia HM, Serruys PW; TROFI Investigators. Randomized study to assess the effect of thrombus aspiration on flow area in patients with ST-elevation myocardial infarction: an optical frequency domain imaging study–TROFI trial.Eur Heart J. 2013; 34:1050–1060. doi: 10.1093/eurheartj/ehs456.CrossrefMedlineGoogle Scholar
    • 27. De Carlo M, Aquaro GD, Palmieri C, Guerra E, Misuraca L, Giannini C, Lombardi M, Berti S, Petronio AS.A prospective randomized trial of thrombectomy versus no thrombectomy in patients with ST-segment elevation myocardial infarction and thrombus-rich lesions: MUSTELA (MUltidevice Thrombectomy in Acute ST-Segment ELevation Acute Myocardial Infarction) trial.JACC Cardiovasc Interv. 2012; 5:1223–1230. doi: 10.1016/j.jcin.2012.08.013.CrossrefMedlineGoogle Scholar
    • 28. Ciszewski M, Pregowski J, Teresińska A, Karcz M, Kalińczuk Ł, Pracon R, Witkowski A, Rużyłło W.Aspiration coronary thrombectomy for acute myocardial infarction increases myocardial salvage: single center randomized study.Catheter Cardiovasc Interv. 2011; 78:523–531. doi: 10.1002/ccd.22933.CrossrefMedlineGoogle Scholar
    • 29. Dudek D, Mielecki W, Burzotta F, Gasior M, Witkowski A, Horvath IG, Legutko J, Ochala A, Rubartelli P, Wojdyla RM, Siudak Z, Buchta P, Pregowski J, Aradi D, Machnik A, Hawranek M, Rakowski T, Dziewierz A, Zmudka K.Thrombus aspiration followed by direct stenting: a novel strategy of primary percutaneous coronary intervention in ST-segment elevation myocardial infarction. Results of the Polish-Italian-Hungarian RAndomized ThrombEctomy Trial (PIHRATE Trial).Am Heart J. 2010; 160:966–972. doi: 10.1016/j.ahj.2010.07.024.CrossrefMedlineGoogle Scholar
    • 30. Liistro F, Grotti S, Angioli P, Falsini G, Ducci K, Baldassarre S, Sabini A, Brandini R, Capati E, Bolognese L.Impact of thrombus aspiration on myocardial tissue reperfusion and left ventricular functional recovery and remodeling after primary angioplasty.Circ Cardiovasc Interv. 2009; 2:376–383. doi: 10.1161/CIRCINTERVENTIONS.109.852665.LinkGoogle Scholar
    • 31. Sardella G, Mancone M, Bucciarelli-Ducci C, Agati L, Scardala R, Carbone I, Francone M, Di Roma A, Benedetti G, Conti G, Fedele F.Thrombus aspiration during primary percutaneous coronary intervention improves myocardial reperfusion and reduces infarct size: the EXPIRA (thrombectomy with export catheter in infarct-related artery during primary percutaneous coronary intervention) prospective, randomized trial.J Am Coll Cardiol. 2009; 53:309–315. doi: 10.1016/j.jacc.2008.10.017.CrossrefMedlineGoogle Scholar
    • 32. Chevalier B, Gilard M, Lang I, Commeau P, Roosen J, Hanssen M, Lefevre T, Carrié D, Bartorelli A, Montalescot G, Parikh K.Systematic primary aspiration in acute myocardial percutaneous intervention: a multicentre randomised controlled trial of the export aspiration catheter.EuroIntervention. 2008; 62:555–561.Google Scholar
    • 33. Chao CL, Hung CS, Lin YH, Lin MS, Lin LC, Ho YL, Liu CP, Chiang CH, Kao HL.Time-dependent benefit of initial thrombosuction on myocardial reperfusion in primary percutaneous coronary intervention.Int J Clin Pract. 2008; 62:555–61.CrossrefMedlineGoogle Scholar
    • 34. Silva-Orrego P, Colombo P, Bigi R, Gregori D, Delgado A, Salvade P, Oreglia J, Orrico P, de Biase A, Piccalò G, Bossi I, Klugmann S.Thrombus aspiration before primary angioplasty improves myocardial reperfusion in acute myocardial infarction: the DEAR-MI (Dethrombosis to Enhance Acute Reperfusion in Myocardial Infarction) study.J Am Coll Cardiol. 2006; 48:1552–1559. doi: 10.1016/j.jacc.2006.03.068.CrossrefMedlineGoogle Scholar
    • 35. De Luca L, Sardella G, Davidson CJ, De Persio G, Beraldi M, Tommasone T, Mancone M, Nguyen BL, Agati L, Gheorghiade M, Fedele F.Impact of intracoronary aspiration thrombectomy during primary angioplasty on left ventricular remodelling in patients with anterior ST elevation myocardial infarction.Heart. 2006; 92:951–957. doi: 10.1136/hrt.2005.074716.CrossrefMedlineGoogle Scholar
    • 36. Kaltoft A, Bøttcher M, Nielsen SS, Hansen HH, Terkelsen C, Maeng M, Kristensen J, Thuesen L, Krusell LR, Kristensen SD, Andersen HR, Lassen JF, Rasmussen K, Rehling M, Nielsen TT, Bøtker HE.Routine thrombectomy in percutaneous coronary intervention for acute ST-segment-elevation myocardial infarction: a randomized, controlled trial.Circulation. 2006; 114:40–47. doi: 10.1161/CIRCULATIONAHA.105.595660.LinkGoogle Scholar
    • 37. Burzotta F, Trani C, Romagnoli E, Mazzari MA, Rebuzzi AG, De Vita M, Garramone B, Giannico F, Niccoli G, Biondi-Zoccai GG, Schiavoni G, Mongiardo R, Crea F.Manual thrombus-aspiration improves myocardial reperfusion: the randomized evaluation of the effect of mechanical reduction of distal embolization by thrombus-aspiration in primary and rescue angioplasty (REMEDIA) trial.J Am Coll Cardiol. 2005; 46:371–376. doi: 10.1016/j.jacc.2005.04.057.CrossrefMedlineGoogle Scholar
    • 38. Lagerqvist B, Fröbert O, Olivecrona GK, Gudnason T, Maeng M, Alström P, Andersson J, Calais F, Carlsson J, Collste O, Götberg M, Hårdhammar P, Ioanes D, Kallryd A, Linder R, Lundin A, Odenstedt J, Omerovic E, Puskar V, Tödt T, Zelleroth E, Östlund O, James SK.Outcomes 1 year after thrombus aspiration for myocardial infarction.N Engl J Med. 2014; 371:1111–1120. doi: 10.1056/NEJMoa1405707.CrossrefMedlineGoogle Scholar
    • 39. Stone GW, Witzenbichler B, Godlewski J, Dambrink JH, Ochala A, Chowdhary S, El-Omar M, Neunteufl T, Metzger DC, Dizon JM, Wolff SD, Brener SJ, Mehran R, Maehara A, Gibson CM.Intralesional abciximab and thrombus aspiration in patients with large anterior myocardial infarction: one-year results from the INFUSE-AMI trial.Circ Cardiovasc Interv. 2013; 6:527–534. doi: 10.1161/CIRCINTERVENTIONS.113.000644.LinkGoogle Scholar
    • 40. Vlaar PJ, Svilaas T, van der Horst IC, Diercks GF, Fokkema ML, de Smet BJ, van den Heuvel AF, Anthonio RL, Jessurun GA, Tan ES, Suurmeijer AJ, Zijlstra F.Cardiac death and reinfarction after 1 year in the Thrombus Aspiration during Percutaneous coronary intervention in Acute myocardial infarction Study (TAPAS): a 1-year follow-up study.Lancet. 2008; 371:1915–1920. doi: 10.1016/S0140-6736(08)60833-8.CrossrefMedlineGoogle Scholar
    • 41. Lambert PC, Sutton AJ, Abrams KR, Jones DR.A comparison of summary patient-level covariates in meta-regression with individual patient data meta-analysis.J Clin Epidemiol. 2002; 55:86–94.CrossrefMedlineGoogle Scholar
    • 42. Bajaj NS, Ather S, Gaba S, Aggarwal H, Arora P, Ghimire G, Bhatia V, Parashar A, Ahmed MI, Ahmed A, Leesar MA.Glycoprotein IIb/IIIa inhibitors improve mortality after aspiration thrombectomy in patients with ST-segment elevation myocardial infarction.Int J Cardiol. 2015; 187:206–207. doi: 10.1016/j.ijcard.2015.03.173.CrossrefMedlineGoogle Scholar