Impact of intracoronary aspiration thrombectomy during primary angioplasty on left ventricular remodelling in patients with anterior ST elevation myocardial infarction

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.

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.

Reducing Cardiac Injury during ST-Elevation Myocardial Infarction: A Reasoned Approach to a Multitarget Therapeutic Strategy

The significant reduction in ‘ischemic time’ through capillary diffusion of primary percutaneous intervention (pPCI) has rendered myocardial-ischemia reperfusion injury (MIRI) prevention a major issue in order to improve the prognosis of ST elevation myocardial infarction (STEMI) patients. In fact, while the ischemic damage increases with the severity and the duration of blood flow reduction, reperfusion injury reaches its maximum with a moderate amount of ischemic injury. MIRI leads to the development of post-STEMI left ventricular remodeling (post-STEMI LVR), thereby increasing the risk of arrhythmias and heart failure. Single pharmacological and mechanical interventions have shown some benefits, but have not satisfactorily reduced mortality. Therefore, a multitarget therapeutic strategy is needed, but no univocal indications have come from the clinical trials performed so far. On the basis of the results of the consistent clinical studies analyzed in this review, we try to design a randomized clinical trial aimed at evaluating the effects of a reasoned multitarget therapeutic strategy on the prevention of post-STEMI LVR. In fact, we believe that the correct timing of pharmacological and mechanical intervention application, according to their specific ability to interfere with survival pathways, may significantly reduce the incidence of post-STEMI LVR and thus improve patient prognosis.

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.

Clinical controversies in anticoagulation monitoring and antithrombin supplementation for ECMO

During extracorporeal membrane oxygenation (ECMO), a delicate balance is required to titrate systemic anticoagulation to prevent thrombotic complications within the circuit and prevent bleeding in the patient. Despite focused efforts to achieve this balance, the frequency of both thrombotic and bleeding events remains high. Anticoagulation is complicated to manage in this population due to the complexities of the hemostatic system that are compounded by age-related developmental hemostatic changes, variable effects of the etiology of critical illness on hemostasis, and blood-circuit interaction. Lack of high-quality data to guide anticoagulation management in ECMO patients results in marked practice variability among centers. One aspect of anticoagulation therapy that is particularly challenging is the use of antithrombin (AT) supplementation for heparin resistance. This is especially controversial in the neonatal and pediatric population due to the baseline higher risk of bleeding in this cohort. The indication for AT supplementation is further compounded by the potential inaccuracy of the diagnosis of heparin resistance based on the standard laboratory parameters used to assess heparin effect. With concerns regarding the adverse impact of bleeding and thrombosis, clinicians and institutions are faced with making difficult, real-time decisions aimed at optimizing anticoagulation in this setting. In this clinically focused review, the authors discuss the complexities of anticoagulation monitoring and therapeutic intervention for patients on ECMO and examine the challenges surrounding AT supplementation given both the historical and current perspectives summarized in the literature on these topics.

Determinants of Improvement of Mid-term Ejection Fraction in Patients with Acute Myocardial Infarction

Persistent severe left ventricular (LV) systolic dysfunction after acute myocardial infarction (AMI) is associated with increased morbidity and mortality, whereas mid-term recovery of LV systolic function after AMI is associated with better long-term outcomes. The purpose of this study was to investigate the determinants of mid-term improvement of LV ejection fraction (EF) in AMI patients. We included 210 AMI patients who had modified Simpson EF both at the index admission and mid-term follow up. The difference of EF between the index admission and mid-term follow-up was calculated in all study patients. The EF improvement group was defined as mid-term ≥ 10% EF increase compared with the index admission EF. Of 210 AMI patients, 46 (21.9%) were allocated to the EF improvement group and 164 (78.1%) to the non-EF improvement group. Brain natriuretic peptide (BNP) at the timing of admission was significantly greater in the EF improvement group (735.8 ± 1077.6 pg/mL) than in the non-EF improvement group (239.0 ± 419.8 pg/mL) (P < 0.001). Multivariate logistic regression analysis revealed that log₁₀ BNP at the timing of admission (OR 3.36, 95% CI 1.69-6.66, P < 0.001) and left main trunk-left anterior descending artery (LM-LAD) as the infarct-related artery (OR 3.34, 95% CI 1.59-7.02, P = 0.001) were significantly associated with EF improvement. In conclusion, elevated BNP at the timing of admission and LM-LAD as the infarct-related artery were significantly associated with mid-term LVEF recovery. Our results support aggressive acute treatment for those severe AMI, because the possibility of mid-term LVEF recovery is greater compared with other AMI.

Thrombus aspiration catheter improve the myocardial reperfusion of STEMI patients with high thrombus load during the emergency PCI operation

OBJECTIVE

This study aims to discuss the efficacy and safety of the application of thrombus aspiration catheters during emergency PCI operations for acute ST-elevation myocardial infarction (STEMI) patients with high thrombus load.

METHODS

A total of 204 patients diagnosed with acute STEMI and high thrombus load in the Sixth Affiliated Hospital of Guangxi Medical University from July 1, 2016 to June 30, 2017 were selected for the present study. These patients were randomly divided into two groups: thrombus catheter aspiration group (group A, n = 101), and balloon dilatation group (group B, n = 103). The blood flow of the culprit coronary artery in the thrombolysis in myocardial infarction (TIMI) immediately after the emergency PCI operation in these two groups of patients was recorded. Then, an echocardiogram was performed to determine the left ventricular end-diastolic diameter (LVEDD) and left ventricular ejection fraction (LVEF) after the operation, and data on major adverse cardiovascular events (MACE) during the 30 days of postoperative follow-up were collected.

RESULTS

The comparative difference between these two groups of patients in terms of hypertension, smoking, diabetes, usage rate of GPIIb/IIIa receptor antagonist, time from hospitalization to balloon dilatation (D2B) and other basic clinical data was not statistically significant (P > 0.05). The postoperative TIMI flow grade of these two groups of patients improved, and the comparative difference between the data obtained from these two groups was statistically significant (P < 0.05). The comparative difference between these two groups in terms of LVEDD and LVEF at 7 days after the operation was not statistically significant (P > 0.05). There was a difference in the occurrence rate of MACE in these two groups of patients during the 30 days of postoperative follow-up, but the comparative difference between these two groups was not statistically significant (P = 0.335).

CONCLUSION

The application of thrombus aspiration catheter during the emergency PCI operation of STEMI patients with high thrombus load can better improve the myocardial reperfusion. There is no basis for increasing the stroke occurrence risk. However, it obviously fails to improve the recent prognosis and more studies need to explore its effect on myocardial remodeling and major adverse cardiovascular events.

Measurement of left ventricular end-diastolic pressure improves the prognostic utility of the Global Registry of Acute Coronary Events score in patients with ST-segment elevation myocardial infarction

AIMS

This study aimed to evaluate the clinical significance of measuring left ventricular end-diastolic pressure (LVEDP) in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

We retrospectively analysed clinical data from 277 patients with STEMI between October 2006 and June 2014. LVEDP and left ventricular ejection fraction (LVEF) were perioperatively measured during percutaneous coronary intervention (PCI). The primary endpoint was a major adverse cardiac event (MACE) such as cardiac death, non-fatal myocardial infarction, or hospitalisation due to heart failure during the observation period. The independent predictors were identified by Cox proportional hazards regression analysis. Continuous net reclassification improvement (cNRI) and integrated discrimination improvement (IDI) were conducted to assess the incremental prognostic value of adding cardiovascular parameters, including LVEDP, to the Global Registry of Acute Coronary Events (GRACE) score. The mean follow-up period was 44±31 months. A MACE occurred in 33 patients (12.0%). In the Cox proportional hazards regression model, after adjusting for confounding factors, LVEDP was an independent predictor of a MACE (hazard ratio [HR] 1.11, 95% confidence interval [CI]: 1.06-1.17, p<0.001). In addition, the predictive value of the GRACE score for a MACE was significantly improved by LVEDP (NRI 0.66, 95% CI: 0.32-1.01, p<0.001; IDI 0.06, 95% CI: 0.02-0.11, p=0.001), but not by LVEF (NRI 0.14, 95% CI: -0.22-0.50, p=0.44; IDI 0.01, 95% CI: 0.00-0.03, p=0.11).

CONCLUSIONS

The results of this study demonstrated that evaluating LVEDP provides an additive prognostic value over conventional risks estimated by the GRACE score among STEMI patients.

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.

Thrombus Aspiration for ST-Segment-Elevation Myocardial Infarction in Modern Era: Still an Issue of Debate?

The role of manual thrombus aspiration (TA) during primary percutaneous coronary intervention (PPCI) for acute ST-segment-elevation myocardial infarction has been a matter of intense research and debate now. Although recent randomized controlled clinical trials (notably TASTE [Thrombus Aspiration in ST-Elevation Myocardial Infarction in Scandinavia] and TOTAL [Trial of Routine Aspiration Thrombectomy With PCI Versus PCI Alone in Patients With STEMI]) do not supply evidence supporting the routine use of TA in patients with ST-segment-elevation myocardial infarction, manual TA remains a therapeutic option for interventional cardiologists when treating patients with substantial thrombus burden during PPCI. It remains unknown whether patients might actually benefit from TA applied in a more selective manner depending on the thrombus burden during PPCI, instead of routine application. In this review, we summarize current knowledge on the instruments used in the TA procedure, positive as well as negative clinical effects of TA during PPCI, and analyze the potential reasons for observed effects, in an effort to help the clinical decision making by physicians for the use of TA in individual ST-segment-elevation myocardial infarction patients during PPCI.

Long-term outcomes with aspiration thrombectomy for patients undergoing primary percutaneous coronary intervention: A meta-analysis of randomized trials

Randomized clinical trials that examined long-term clinical outcomes of routine aspiration thrombectomy prior to primary percutaneous coronary intervention (PCI) in patients with acute ST-segment elevation myocardial infarction have yielded different results. We hypothesized that the routine use of manual thrombus aspiration prior to primary PCI lacks long-term clinical benefits. Electronic databases were searched for randomized trials comparing routine aspiration thrombectomy and conventional PCI. We included only trials that reported clinical outcomes beyond 6 months. The primary outcome was all-cause mortality, and the secondary outcomes included major adverse cardiovascular events, re-infarction, cardiovascular mortality, and stent thrombosis (ST). A DerSimonian-Laird model was used to construct the summary estimates risk ratio (RR). We retrieved 18 trials with 20 641 ST-segment elevation myocardial infarction patients, of whom 10 331 patients underwent routine aspiration thrombectomy prior to primary PCI. At a mean follow-up of 12 months, there was no significant decrease in the risk of all-cause mortality (RR: 0.93, 95% confidence interval [CI]: 0.82-1.05, P = 0.22), major adverse cardiac events (RR: 0.95, 95% CI: 0.87-1.03, P = 0.18), re-infarction (RR: 0.95, 95% CI: 0.80-1.13, P = 0.59), cardiovascular mortality (RR: 0.80, 95% CI: 0.47-1.36, P = 0.40), or ST (RR: 0.80, 95% CI: 0.63-1.01, P = 0.06) with routine aspiration thrombectomy. Routine aspiration thrombectomy prior to primary PCI was not associated with a reduction in long-term mortality or clinical outcomes. Future randomized trials are warranted to further evaluate the role of aspiration thrombectomy in select patients and coronary lesions.

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.

Meta-Analysis of the Long-Term Effect of Routine Aspiration Thrombectomy in Patients Undergoing Primary Percutaneous Coronary Intervention

American College of Cardiology Foundation/American Heart Association guidelines no longer recommend the use of routine aspiration thrombectomy during primary percutaneous coronary intervention (PCI). This is based on evidence from recent randomized controlled trials (RCTs) that suggests that the long-term benefits of aspiration thrombectomy were previously overestimated. We conducted a systematic review and meta-analysis of RCTs to examine the effect of routine aspiration thrombectomy during primary PCI versus primary PCI alone on markers of reperfusion immediately after PCI and on clinical outcomes at ≥6 months. We systematically searched Medline, EMBASE, and the Cochrane Library of Clinical trials for RCTs published in English or French with follow-up ≥6 months. Data were pooled using random-effects models. Eighteen publications (containing data from 14 RCTs, n = 20,285) met our inclusion criteria. Aspiration thrombectomy was associated with higher rates of ST-segment resolution (relative risk [RR] 1.22, 95% CI 1.07 to 1.40) and myocardial blush grade 3 (RR 1.30, 95% CI 1.01 to 1.67) and a reduced risk of no reflow immediately after PCI (RR 0.63, 95% CI 0.40 to 0.98). However, thrombectomy was not associated with our primary outcome of all-cause mortality at longest available follow-up (RR 0.92, 95% CI 0.81 to 1.04). Similar results were obtained for myocardial infarction and target vessel/lesion revascularization. Thrombectomy also increased the risk of stroke (RR 1.59, 95% CI 1.07 to 2.35). In conclusion, routine aspiration thrombectomy during primary PCI has some short-term clinical benefits but does not improve outcomes ≥6 months and increases the risk of stroke.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Additional manual thrombus aspiration for ST-segment elevation myocardial infarction during percutaneous coronary intervention: an updated meta-analysis

BACKGROUND

The clinical efficacy and safety of adjunctive thrombus aspiration (TA) in patients with ST-segment elevation myocardial infarction (STEMI) during percutaneous coronary intervention (PCI) remain controversial.

METHODS

Twenty five eligible randomized controlled trials were included to compare the use of thrombus aspiration (TA) with PCI and PCI-only for STEMI. The primary endpoint was all-cause mortality and death. The secondary endpoints were major adverse cardiac events (MACE), recurrent infarction (RI), target vessel revascularization (TVR), stent thrombosis (ST), perfusion surrogate markers and stroke.

RESULTS

TIMI flow grade 3 and MBG 2-3 were significantly increased in the TA plus PCI arm compared with the PCI-only arm [relative risk (RR): 1.05, 95% confidence intervals (CI): 1.02-1.09, P = 0.004] and (RR: 1.68, 95% CI: 1.40-2.00, P < 0.001), respectively. There were no significant differences in all-cause mortality, MACEs, TVR and ST rates between the two groups. The RI rate was lower in the TA plus PCI arm than that in the PCI-only arm with short-term follow-up duration (RR: 0.60, 95% CI: 0.38-0.96, P = 0.03), but there was no significant difference in RI incidence over the medium- or long-term follow-up periods (RR: 1.00, 95% CI: 0.77-1.29, P = 0.98), and (RR: 0.96, 95% CI: 0.81-1.15, P = 0.69), respectively. There were statistically significant differences in the rates of crude stroke and stroke over the medium- or long-term follow-up periods and the crude stroke rate in the TA plus PCI (RR: 1.60, 95% CI: 1.08-2.38, P = 0.02) and (RR: 1.43, 95% CI: 1.03-1.98, P = 0.03), respectively; this was not observed between the two arms during the short-term follow-up period (RR: 1.47, 95% CI: 0.97-2.21, P = 0.07).

CONCLUSIONS

Routine TA-assisted PCI in STEMI patients can improve myocardial reperfusion and get limited benefits related to the clinical endpoints, which may be associated with stroke risk.

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.

The Rise and Fall of Routine Manual Thrombectomy for ST-Elevation Myocardial Infarction

Manual thrombectomy (MT) with an aspiration catheter is frequently used in primary percutaneous coronary intervention (PPCI) for acute myocardial infarction with ST-segment elevation (STEMI). It is used to reduce the thrombus burden and the risk of no-reflow in the infarct related artery. This article summarises a chronological overview of the available evidence for its routine use in PPCI. An early series of small randomised controlled trials (RCTs) have shown a benefit of PPCI with MT over percutaneous coronary intervention alone, mainly when considering intermediate endpoints reflecting myocardial reperfusion. However, a recent series of large multicentre RCTs failed to corroborate the initial enthusiasm for MT, showing no improved benefit on hard endpoints such as mortality when compared with PPCI without MT. Furthermore, the largest RCT to date raised safety concerns after reporting an increased stroke risk after MT. We review the background, value, and implications of the current evidence before concluding that the routine use of MT in PPCI for STEMI should not be encouraged.

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.

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.

Effect of thrombus aspiration on postprocedural outcomes in elderly patients with acute ST-elevation myocardial ınfarction

AIM

The effects of thrombus aspiration (TA) during primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) have been evaluated in several studies. The aim of the present study was to evaluate postprocedural outcomes in elderly STEMI patients who have a tendency for vasoconstruction and decreased coronary flow reserve.

METHODS

A total of 124 patients (aged ≥65 years) with STEMI who underwent primary PCI (71.2% men, 29.8% women, mean age 74 ± 7 years) were enrolled in the study. Patients were divided into two groups according to intervention with and without TA. Acute angiographic, electrocardiographic and echocardiographic results were compared between the two groups.

RESULTS

TA was carried out in 42 patients (33.8%). Baseline clinical characteristics and predischarge echocardiographic features did not differ between TA(+) and TA(-) patients (ejection fraction 37.26 ± 8.91 vs 38.53 ± 11.18, P = 0.558, wall motion index 1.69 ± 0.38 vs 1.76 ± 0.37, P = 0.316, septal E' 0.058 ± 0.022 vs 0.053 ± 0.015, P = 0.267, E/E' 11.82 ± 4.30 vs 13.12 ± 5.09, P = 0.370). Acute angiographic and electrocardiographic results did not differ between the two groups, but were slightly better in the thrombectomy group than those without TA corrected TIMI frame count (31.63 ± 16.33 vs 34.97 ± 15.81, P = 0.197, TIMI-3 88.1% vs 79.3%, P = 0.223, ST segment resolution 81.3% vs 70.3%, P = 0.250).

CONCLUSIONS

Thrombectomy during primary PCI has no effect on postprocedural outcomes in an elderly group with STEMI. Geriatr Gerontol Int 2015; ●●: ●●-●●.

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.

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.

Thrombus aspiration in acute myocardial infarction: Rationale and indication

Reperfusion of myocardial tissue is the main goal of primary percutaneous coronary intervention (PPCI) with stent implantation in the treatment of acute ST-segment elevation myocardial infarction (STEMI). Although PPCI has contributed to a dramatic reduction in cardiovascular mortality over three decades, normal myocardial perfusion is not restored in approximately one-third of these patients. Several mechanisms may contribute to myocardial reperfusion failure, in particular distal embolization of the thrombus and plaque fragments. In fact, this is a possible complication during PPCI, resulting in microvascular obstruction and no-reflow phenomenon. The presence of a visible thrombus at the time of PPCI in patients with STEMI is associated with poor procedural and clinical outcomes. Aspiration thrombectomy during PPCI has been proposed to prevent embolization in order to improve these outcomes. In fact, the most recent guidelines suggest the routine use of manual aspiration thrombectomy during PPCI (class IIa) to reduce the risk of distal embolization. Even though numerous international studies have been reported, there are conflicting results on the clinical impact of aspiration thrombectomy during PPCI. In particular, data on long-term clinical outcomes are still inconsistent. In this review, we have carefully analyzed literature data on thrombectomy during PPCI, taking into account the most recent studies and meta-analyses.

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.

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.

Catheter Aspiration after Every Stage during Primary Percutaneous Angioplasty; ADMIT Trial

We assess the epicardial and microcirculation flow characteristics, and clinical outcome by using catheter aspiration after each stage of primary percutaneous coronary intervention (PPCI). Conflicting data are reported regarding early and late benefit of using aspiration catheter in the initial phase PPCI. A total of 100 patients with ST-segment elevation acute myocardial infarction (STEMI) were included: 51 underwent PPCI without using an aspiration device (SA group) and 49 underwent PPCI by activating an aspiration catheter after each stage of procedure; wiring, ballooning and stenting, respectively (MA group). Thrombolysis in myocardial infarction (TIMI) flow grade, TIMI frame counts and myocardial blush grade (MBG) were evaluated in each group during every stage of procedure. Major adverse cardiac events were evaluated in the index hospitalization and during 30 and 180 days of follow-up. A TIMI flow grade 2-3 was more prevalent in the MA group compared with the SA group only after wiring: 65.9 versus 39.1% (p = 0.01), but TIMI frame counts were lower in the MA versus SA group throughout all procedural steps. MBG 2-3 was statistically higher in the MA group compared with the SA group mainly after wiring. After stenting there were no significant changes in both epicardial and microcirculation flow parameters. There were no significant differences between the groups in early and late clinical outcomes. Improved flow parameters were noticed in the MA group only by activating the aspiration device after wiring. This early advantage disappeared after stenting. The initial better flow characteristic in the MA group was not translated into a better early or late clinical outcome.

The randomized physiologic assessment of thrombus aspiration in patients with acute ST-segment elevation myocardial infarction trial (PATA STEMI): study rationale and design

INTRODUCTION

Routine thrombus aspiration is proposed to be superior to conventional primary percutaneous coronary intervention (PCI) in terms of improved myocardial perfusion, in patients with ST-segment elevation acute myocardial infarction (STEMI). However, myocardial perfusion after thrombus aspiration has not been evaluated by a quantitative, invasive method. We intend to determine whether manual thrombus aspiration in the infarct-related coronary artery increases myocardial perfusion assessed by index of microcirculatory resistance (IMR) compared with conventional primary PCI.

STUDY DESIGN

PATA STEMI is a single-center, prospective, randomized trial with a planned inclusion of 128 patients with the first STEMI. Prior to coronary angiography, patients are randomly assigned to thrombus aspiration using the Eliminate aspiration catheter (Terumo Medical Supply, Japan) or to conventional primary PCI. After completion of primary PCI, IMR is determined both in infarct-related artery and in noninfarct-related arteries without critical stenoses. The primary end-point is a group mean value of IMR after thrombus aspiration compared with conventional primary PCI. Secondary end-points are myocardial perfusion grade, resolution of ST-segment elevation, enzymatic estimation of infarct size, left ventricular remodeling assessed by echocardiographic indices, and major adverse cardiac events rate at 1, 6, and 12 months.

CONCLUSION

If manual thrombus aspiration significantly reduces microcirculatory resistance, thereby improving myocardial perfusion, it may become the routine strategy in primary PCI.

Spontaneous and procedural plaque embolisation in native coronary arteries: pathophysiology, diagnosis, and prevention

The detachment of atherothrombotic material from the atherosclerotic coronary plaque and downstream embolisation is an underrecognized phenomenon and it causes different degrees of impairment of the coronary microcirculation. During treatment of obstructive atherosclerotic plaque by percutaneous coronary intervention (PCI) distal embolisation (DE) is considered to be inevitable and it is associated with potential clinical and prognostic implications. This review aims to assess the main aspects of both spontaneous and procedural DE, analyze their different pathophysiology, provide specific insights on the main diagnostic tools for their identification, and finally focus on the main strategies for their treatment and prevention.

Manual vs mechanical thrombectomy during PCI for STEMI: a comprehensive direct and adjusted indirect meta-analysis of randomized trials

Thrombus removal by manual thrombectomy improves coronary flow and myocardial perfusion after percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI); growing interest is on mechanical devices for thrombectomy which may allow a larger thrombus removal as compared to manual devices. We aimed to perform the first direct and adjusted indirect meta-analysis of studies on manual and mechanical thrombectomy in PCI for STEMI.

METHODS

The literature was scanned for direct and indirect randomized comparisons between manual and/or mechanical thrombectomy and/or placebo by formal searches of electronic databases from November 1994 to June 2013. Clinical and procedural endpoints were selected.

RESULTS

Three studies directly comparing (2 RCTs and 1 non-randomized; N = 513) and 21 RCTs (N = 4514) indirectly comparing the two strategies were included in the meta-analysis. The direct meta-analysis showed comparable rates of survival (p = 0.88), re-infarction (MI) (p = 0.84) and procedural outcomes between the two strategies; direct evidence was however limited in number of enrolled patients. The indirect meta-analysis showed a superior reduction in mortality with manual thrombectomy compared to mechanical thrombectomy in the overall analysis (p = 0.01); by excluding trials with low percentage of patients with intracoronary thrombus (< 50%) at baseline, the two strategies were comparable in survival, but mechanical thrombectomy was associated with a significant reduction in re-MI (p < 0.001) and stroke (p = 0.04).

CONCLUSIONS

This meta-analysis lends support to mechanical thrombectomy in the population with high thrombus burden only where, compared to manual thrombectomy, it is likely to provide higher benefits.

A review of thrombectomy devices

Acute coronary syndrome is associated with a high incidence of thrombus. The presence of coronary thrombus is often not appreciated on coronary angiography; however, simultaneous use of angioscopy or intravascular ultrasound increases the detection of thrombus. Forceful coronary injection, passage of intracoronary devices, balloon angioplasty and stenting in the presence of thrombus contribute to distal embolization by disrupting the thrombus. Clinically, intracoronary thrombus is associated with higher rates of death, myocardial infarction and target vessel revascularization. Removal of thrombus results in the improvement of markers of perfusion, which includes resolution of ST segment elevation, higher myocardial blush grade, and an increase in final thrombolysis in myocardial infarction flow as well as lower mortality. In this article, the authors discuss different mechanical thrombectomy devices and the literature available for their use in acute coronary syndrome.