No Beneficial Effects of Coronary Thrombectomy on Left Ventricular Systolic and Diastolic Function in Patients with Acute S-T Elevation Myocardial Infarction: A Randomized Clinical Trial

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

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.

Treating thrombus in the coronary arteries

Primary percutaneous coronary intervention (PCI) has greatly improved outcomes in patients with ST-elevation myocardial infarction (STEMI) and has, therefore, become the preferred reperfusion strategy for this patient group. The goal of primary PCI is to achieve a thrombolysis in myocardial infarction (TIMI) 3 flow and also to restore adequate perfusion at the myocardial level. Distal thrombus embolization during primary PCI occurs frequently and is also associated with compromised long-term outcomes. In this article, we provide an overview of the treatment of thrombus and the role of thrombectomy in PCI for STEMI.

Thrombectomy Devices in Coronary Intervention

Primary percutaneous coronary intervention is the favored mode of reperfusion therapy for ST-elevation myocardial infarction (STEMI) when able to be performed in a timely fashion in appropriately selected patients. However, controversy about the role of coronary thrombectomy in the management of STEMI persists because of a paucity of favorable historical data. After the TAPAS trial thrombectomy has gained favor in recent years. The results of the TOTAL, TASTE, and SMART percutaneous coronary intervention trials will provide further insight into the use of thrombectomy in STEMI. This article examines the relevant trial evidence regarding how to best manage and apply thrombectomy in clinical practice.

Compulsive Thrombus Management in STEMI Interventions

Thrombus is a fundamental concept in the pathophysiology of ST-elevated myocardial infarction (STEMI). Distal embolization and no reflow are associated with less angiographic success, reduced myocardial blush, less ST resolution after primary percutaneous coronary intervention, larger enzymatic infarct size, lower left ventricular ejection fraction at discharge, and higher long-term mortality. We believe that with the use of thrombectomy devices, these shortcomings can be minimized. Based on our experience from the Single Individual Community Experience Registry (SINCERE) database, we formulated a selective thrombus burden management strategy (the Mehta classification) for thrombus management.

Safety and efficacy of thrombectomy in patients undergoing primary percutaneous coronary intervention for acute ST elevation MI: a meta-analysis of randomized controlled trials

BACKGROUND

Clinical trials comparing thrombectomy devices with conventional percutaneous coronary interventions (PCI) in patients with acute ST elevation myocardial infarction (STEMI) have produced conflicting results. The objective of our study was to systematically evaluate currently available data comparing thrombectomy followed by PCI with conventional PCI alone in patients with acute STEMI.

METHODS

Seventeen randomized trials (n = 3,909 patients) of thrombectomy versus PCI were included in this meta-analysis. We calculated the summary odds ratios for mortality, stroke, post procedural myocardial blush grade (MBG), thrombolysis in myocardial infarction (TIMI) grade flow, and post procedural ST segment resolution (STR) using random-effects and fixed-effects models.

RESULTS

There was no difference in risk of 30-day mortality (44/1914 vs. 50/1907, OR 0.84, 95% CI 0.54-1.29, P = 0.42) among patients randomized to thrombectomy, compared with conventional PCI. Thrombectomy was associated with a significantly greater likelihood of TIMI 3 flow (1616/1826 vs. 1533/1806, OR 1.41, P = 0.007), MBG 3 (730/1526 vs. 486/1513, OR 2.42, P < 0.001), STR (923/1500 vs. 715/1494, OR 2.30, P < 0.001), and with a higher risk of stroke (14/1403 vs. 3/1413, OR 2.88, 95% CI 1.06-7.85, P = 0.04). Outcomes differed significantly between different device classes with a trend towards lower mortality with manual aspiration thrombectomy (MAT) (21/949 vs.36/953, OR 0.59, 95% CI 0.35-1.01, P = 0.05), whereas mechanical devices showed a trend towards higher mortality (20/416 vs.10/418, OR 2.07, 95% CI 0.95-4.48, P = 0.07).

CONCLUSIONS

Thrombectomy devices appear to improve markers of myocardial perfusion in patients undergoing primary PCI, with no difference in overall 30-day mortality but an increased likelihood of stroke. The clinical benefits of thrombectomy appear to be influenced by the device type with a trend towards survival benefit with MAT and worsening outcome with mechanical devices.

Adjunctive thrombectomy for acute myocardial infarction: A bayesian meta-analysis

BACKGROUND

In available trials and meta-analyses, adjunctive thrombectomy in acute myocardial infarction (MI) improves markers of myocardial reperfusion but has limited effects on clinical outcomes. Thrombectomy devices simply aspirate thrombus or mechanically fragment it before aspiration. Simple aspiration thrombectomy may offer a distinct advantage.

METHODS AND RESULTS

We identified 21 eligible trials (16 that used a simple aspiration thrombectomy device) involving 4299 patients with ST-segment elevation MI randomized to reperfusion therapy by primary percutaneous coronary intervention with or without thrombectomy. By using Bayesian meta-analysis methods, we found that thrombectomy yielded substantially less no-reflow (odds ratio [OR], 0.39; 95% credible interval [CrI], 0.18 to 0.69), more ST-segment resolution > or =50% (OR, 2.22; 95% CrI, 1.60 to 3.23), and more thrombolysis in myocardial infarction/myocardial perfusion grade 3 (OR, 2.50; 95% CrI, 1.48 to 4.41). There was no evidence for a decrease in death (OR, 0.94; 95% CrI, 0.47 to 1.80), death, recurrent MI, or stroke (OR, 1.07; 95% CrI, 0.63 to 1.92) with thrombectomy. Restriction of the analysis to trials that used simple aspiration thrombectomy devices did not yield substantially different results, except for a positive effect on postprocedure thrombolysis in myocardial infarction grade 3 flow (OR, 1.49; 95% CrI, 1.14 to 1.99).

CONCLUSIONS

In this Bayesian meta-analysis, adjunctive thrombectomy improves early markers of reperfusion but does not substantially effect 30-day post-MI mortality, reinfarction, and stroke. The use of aspiration thrombectomy devices is not associated with a reduction in post-MI clinical outcomes. Thrombectomy is one of the rare effective preventive measures against no-reflow.

Effects of distal protection on left ventricular function in acute anterior myocardial infarction: a Doppler echocardiographic study

Whether distal protection devices (DPDs) during percutaneous coronary intervention (PCI) can improve myocardial function in patients with acute myocardial infarction (AMI) is still under debate. Using tissue Doppler imaging (TDI), we evaluate the global and regional left ventricular systolic and diastolic functions in patients with anterior AMI using DPDs compared with conventional PCI. Ninety-six patients with anterior AMI were randomly assigned to either PCI with DPDs (DPD, n = 46) or traditional PCI (control, n = 50) groups. At the 3- and 6-month follow-ups, the DPD group had a higher left ventricular ejection fraction than the control group (51.6 +/- 3.6 vs. 49.3 +/- 5.3% and 53.0 +/- 3.7 vs. 50.8 +/- 5.2%, respectively; both P < 0.05). Moreover, peak systolic (S (a)) and early diastolic (E (a)) mitral annular velocities obtained by TDI were significantly higher in the DPD group than in the control group (S (a): 7.57 +/- 0.53 vs. 7.12 +/- 0.62 cm/s and 7.71 +/- 0.63 vs. 7.32 +/- 0.59 cm/s; E (a): 7.23 +/- 0.78 vs. 6.89 +/- 0.86 cm/s and 7.49 +/- 0.69 vs. 7.04 +/- 0.85 cm/s, respectively; all P < 0.05). However, systolic and diastolic regional myocardial velocities significantly improved in the DPD group from the 1-month follow-up compared with those in the control group (all P < 0.05). Patients who received treatment with DPDs experienced enhanced improvement of cardiac function. Thus, anterior AMI patients can benefit from DPDs during PCI.