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.

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 mortal- ity, 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 me- diumor 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.

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%). Patientstreated 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 plus intra-infarct-related artery administration of tirofiban improves myocardial perfusion during primary angioplasty for acute myocardial infarction

Background We developed a new combined strategy of thrombus aspiration plus intra-infarct-related artery （IRA） bolus administration of tirofiban via the aspiration catheter in patients with ST-segment elevation myocardial infarction （STEMI）. This strategy can reduce the distal embolism and achieve highly localized concentrations of tirofiban, which can improve myocardial reperfusion without increasing the risk of bleeding. The aim of this study was to investigate whether this combined strategy is superior to thrombus aspiration alone in improving myocardial perfusion in patients with STEMI undergoing primary angioplasty.Results Baseline characteristics of the two groups were well-balanced. The TIMI 3 flow showed a better tendency in the intra-IRA group than in the aspiration alone group （97.22% vs. 87.04%, X2=7.863, P=0.049）. The peak of CK-MB （83.9 （68.9-310.5） U/L vs. 126.1 （74.7-356.7） U/L, P=0.034） and Tnl （42.7 （14.7-113.9） ng/ml vs. 72.5 （59.8-135.3） ng/ml, FMD.029） were lower in the intra-IRA group than in the aspiration alone group. LVEF in the hospital favored the intra-IRA group, （45.7±8.3）% to （42.9±12.1）%, t=1.98, P=0.049. There was a tendency towards a lower MACE at 9-month follow-up in the intra-IRA group although it did not reach statistical difference （Log-rank X2=2.865, P=0.09）. There was no statistical difference in any bleeding events between the two groups.Conclusions Thrombus aspiration plus intra-IRA bolus administration of tirofiban combined with angioplasty may be related with improved myocardium perfusion, saved more myocardium, and resulted in a better clinical prognosis.

Transcatheter Aspiration of Coronary Thrombus in Patients with Acute Myocardial Infarction

Objectives We introduced a simple method of transcatheter aspiration of coronary thrombus during emergency PCI in acute myocardial infarction (AMI) patients. Methods AMI patients presenting proximal coronary lesions with intracoronary thrombus were selected. We used the common coronary wire (0. 014') across the lesion after 7F guiding catheter to the ostium of coronary arteries. Aspiration catheter (Export, PercuSurge) was directly advanced over the wire to the lesion and manually aspirated the thrombus with a 20 - ml syringe at the same time. After thrombus disappeared and occluded arteries reopened, stents were directly implanted. Results 12 cases of AMI received the treatment. After aspiration, the thrombus disappeared in 8 cases, and decreased in another 4 cases. The total occluded artery was directly re- opened and the antegrade flow improved markedly after aspiration in 7 out of 8 cases. 9 patients achieved TIMI 3 flow and TMP 3 grade perfusion flow after stenting, and the other 3 cases were TMP 2. No major cardiac events took place during hospitalization. The LVEF was 64.1 ± 9. 3% before discharge. Conclusions Transcatheter aspiration of thrombus is a simple and effective method to manage the intracoronary thrombus in AMI patients.

Effects of Loading-Dose Statins Combined with PCSK9 Inhibitor Pre-Treatment before Primary Percutaneous Coronary Intervention on the Short-Term Prognosis in Patients with ST-Segment Elevation Myocardial Infarction

Objective:This study was aimed at investigating the effects of preoperative treatment with a loading dose of statins combined with a PCSK9 inhibitor on coronary blood perfusion and short-term cardiovascular adverse events in patients with ST-segment elevation myocardial infarction(STEMI).Method:Sixty-five patients with STEMI who had visited the Shanxi Cardiovascular Disease Hospital between May 2018 and May 2021 were enrolled in the study.The enrolled patients had no history of oral statins or antiplatelet therapy.The patients were divided into a combined treatment group(loading dose of statins combined with PCSK9 inhibitors,35 patients)and a routine treatment group(loading dose of statins only,30 patients).The primary endpoints were thrombolysis in myocardial infarction(TIMI)blood flow grading,corrected TIMI frame count(CTFC),and TIMI myocardial perfusion grading(TMPG),immediately after and 30 days after the operation.The secondary endpoint was a composite endpoint of cardiovascular death,nonfatal myocardial infarction,and target vessel revascularization 30 days after the operation.Results:The combined treatment group had significantly lower CTFC(14.09±8.42 vs 26±12.42,P=0.04)and better TMPG(2.74±0.61 vs 2.5±0.73,P=0.04)than the routine treatment group immediately after the operation.Similarly,the combined treatment group had a significantly lower CTFC(16.29±7.39 vs 26.23±11.53,P=0.04)and significantly better TMPG(2.94±0.24 vs 2.76±0.43,P=0.01)than the routine treatment group 1 month after the operation.Conclusion:Preoperative treatment with a loading dose of high-intensity statins combined with PCSK9 inhibitors increased coronary blood flow and myocardial perfusion after emergency thrombus aspiration in patients with STEMI.However,the treatment did not significantly decrease the incidence of cardiovascular death,nonfatal myocardial infarction,or target vessel revascularization.

Comparison of Diver CE and ZEEK manual aspiration catheters for thrombectomy in ST-segment elevation myocardial infarction

Background A growing volume of data suggests that simple manual thrombus aspiration followed by direct stenting improves myocardial reperfusion and clinical outcome compared with conventional primary PCI, but there is still limited data comparing the in vivo performance among different devices. This study aimed to compare the efficacy and operability of thrombus aspiration by the Diver CE （Invatec, Brescia, Italy） and ZEEK （Zeon Medical Inc., Tokyo, Japan） aspiration catheters in ST-segment elevation myocardial infarction （STEMI） and their impact on 3-month outcome.Methods From September 2004 to June 2008, 298 consecutive patients with STEMI who received manual thrombus aspiration were involved in a single center retrospective analysis. Of them, 229 and 69 were treated with Diver CE and ZEEK aspiration catheters, respectively. Primary endpoints were myocardial blush grade （MBG）, thrombolysis in myocardial infarction （TIMI） flow grade, ST-segment elevation resolution （STR）, device pushability and trackability as judged by the frequency of usage of dual guide wires and aspiration efficacy as indicated by size distribution of aspirated thrombi. Secondary endpoints were 3-month outcome including left ventricular end diastolic diameter （LVEDD）, left ventricular ejection fraction （LVEF）, as well as cardiac death, target lesion revascularization （TLR）, re-infarction and their combination as major adverse cardiac events （MACE）. Results Baseline characteristics were not different between the two groups expect for a higher frequency of temporary cardiac pacing in the ZEEK group （ZEEK） than in the Diver CE group （Diver CE） （0.44% vs 5.8%, P=0.002）. Visible retrieved thrombi were achieved in 65.9% of the Diver CE and 68.1% of the ZEEK （P=0.74）. Aspirated thrombi were categorized as small thrombi （〈3.5 mm）, moderate thrombi （3.5-7.0 mm） and large thrombi （〉7.0 mm）. Small thrombi were more frequently seen in the Diver CE （61.6% vs 42.6%）, whereas moderate and larger thrombi were more frequently found in the ZEEK （38.4% vs 57.4%） （P=0.021）. Rates of dual wire utilization were 1.7% of the Diver CE and 7.2% of the ZEEK （P=0.052）. There were no differences in MBG, STR and TIMI flow grade between the two groups. No differences were found in cardiac death, TLR, re-infarction, MACE, LVEDD and LVEF between the Diver CE and the ZEEK during 3-month follow-up.Conclusions Both Diver CE and ZEEK manual aspiration catheters are effective for thrombectomy in STEMI. In clinical practice, ZEEK presents a stronger aspiration capacity for moderate to large thrombi compared with Diver CE, but Diver CE displays a trend towards better pushability and trackability than ZEEK. Differences in aspiration capacity and operability between Diver CE and ZEEK in this setting do not influence myocardial reperfusion and 3-month outcome.