Does Residual Thrombus After Aspiration Thrombectomy Affect the Outcome of Primary PCI in Patients With ST-Segment Elevation Myocardial Infarction?: An Optical Coherence Tomography Study

Prognostic significance of refractory thrombus in STEMI patients and the role of red cell distribution width: A case-control study

The high thrombus burden of the infarct-related artery (IRA) is associated with the adverse prognosis in ST-segment elevation myocardial infarction (STEMI) patients. Our objectives were to investigate the predictors and evaluate the prognosis of refractory thrombus in STEMI patients. A total of 1305 consecutive patients with STEMI who underwent primary percutaneous coronary intervention (pPCI) were screened. The refractory thrombus group (n = 15) was defined as IRA thrombolysis in myocardial infarction flow < grade 2 after multiple thrombus aspiration (TA). The control group (n = 45) was age- and sex-matched and was selected from the same batch of patients. Baseline hematologic indices were measured before the pPCI. The major adverse cardiovascular events (MACE) were recorded during follow-up. The refractory thrombus group had significantly higher red cell distribution width (RDW) at baseline compared with the control group (13.1 [12.4-13.7] vs 12.6 [12.3-12.8], P = .008). In multivariate logistic regression analysis, RDW was an independent predictor of refractory thrombus (odds ratio: 8.799, 95% CI: 1.240-62.454, P = .030). The area under the receiver-operating characteristic curve of the RDW was 0.730 (95%CI: 0.548-0.912, P = .008). During a mean period of 26 months follow-up, patients in the refractory thrombus group tended to have higher percent MACEs compared with patients in the control group (53.3% vs 6.7%, P < .001). In the present study, we found that the refractory thrombus in STEMI patients was associated with the worse prognosis and the increased RDW might be a potential independent predictor.

Postprocedural Anticoagulation After Primary Percutaneous Coronary Intervention for ST-Segment-Elevation Myocardial Infarction: A Multicenter, Randomized, Double-Blind Trial

BACKGROUND

Postprocedural anticoagulation (PPA) is frequently administered after primary percutaneous coronary intervention in ST-segment-elevation myocardial infarction, although no conclusive data support this practice.

METHODS

The RIGHT trial (Comparison of Anticoagulation Prolongation vs no Anticoagulation in STEMI Patients After Primary PCI) was an investigator-initiated, multicenter, randomized, double-blind, placebo-controlled, superiority trial conducted at 53 centers in China. Patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention were randomly assigned by center to receive low-dose PPA or matching placebo for at least 48 hours. Before trial initiation, each center selected 1 of 3 PPA regimens (40 mg of enoxaparin once daily subcutaneously; 10 U·kg·h of unfractionated heparin intravenously, adjusted to maintain activated clotting time between 150 and 220 seconds; or 0.2 mg·kg·h of bivalirudin intravenously). The primary efficacy objective was to demonstrate superiority of PPA to reduce the primary efficacy end point of all-cause death, nonfatal myocardial infarction, nonfatal stroke, stent thrombosis (definite), or urgent revascularization (any vessel) within 30 days. The key secondary objective was to evaluate the effect of each specific anticoagulation regimen (enoxaparin, unfractionated heparin, or bivalirudin) on the primary efficacy end point. The primary safety end point was Bleeding Academic Research Consortium 3 to 5 bleeding at 30 days.

RESULTS

Between January 10, 2019, and September 18, 2021, a total of 2989 patients were randomized. The primary efficacy end point occurred in 37 patients (2.5%) in both the PPA and placebo groups (hazard ratio, 1.00 [95% CI, 0.63 to 1.57]). The incidence of Bleeding Academic Research Consortium 3 to 5 bleeding did not differ between the PPA and placebo groups (8 [0.5%] vs 11 [0.7%] patients; hazard ratio, 0.74 [95% CI, 0.30 to 1.83]).

CONCLUSIONS

Routine PPA after primary percutaneous coronary intervention was safe but did not reduce 30-day ischemic events.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03664180.

Optical Coherence Tomography Assessment of Coronary Lesions Associated With Microvascular Dysfunction in ST-Segment Elevation Myocardial Infarction

BACKGROUND

Microvascular reperfusion following percutaneous coronary intervention (PCI) is associated with the prognosis of patients with ST-segment elevation myocardial infarction (STEMI). We investigated how plaque characteristics detected by optical coherence tomography (OCT) in STEMI patients affect the status of the microcirculation during PCI.Methods and Results: This retrospective, single-center study was a post hoc analysis basedon the multicenter SALVAGE randomized control trial (NCT03581513) that enrolled 629 STEMI patients, and finally we enrolled 235 patients who underwent PCI and pre-intervention OCT. Microvascular perfusion was evaluated using the Thrombolysis in Myocardial Infarction (TIMI) myocardial perfusion frame count (TMPFC). Patients were divided into 3 groups based on the change in TMPFC from before to after PCI: improving TMPFC (n=11; 4.7%), stable TMPFC (n=182; 77.4%), and worsening TMPFC group (n=42; 17.9%). The proportion of patients with a microcirculation dysfunction before reperfusion was 11.9%, which increased significantly by (P=0.079) 8.5% to 20.4% after reperfusion. Compared with plaque characteristics in the stable and worsening TMPFC groups, the improving TMPFC group had fewer thrombi (90.7% and 90.5% vs. 89.4%, respectively; P=0.018), a lower proportion of plaque rupture (66.5% and 66.3% vs. 54.5%, respectively; P=0.029), and a lower proportion of lipid-rich plaques (89.6% and 88.1% vs. 63.6%, respectively; P=0.036).

CONCLUSIONS

PCI may not always achieve complete myocardial reperfusion. Thrombi, plaque rupture, and lipid-rich plaques detected by OCT can indicate microcirculation dysfunction during the reperfusion period.

Subacute right coronary artery thrombosis treated by using Excimer Laser Coronary Angioplasty: a case report

Background

Managing high thrombotic burden in the context of myocardial infarction remains a challenging scenario.

Case summary

A 51-year-old male was admitted for a subacute inferior myocardial infarction with persistent chest pain. Emergent coronary angiography showed an ostial-proximal thrombotic occlusion of a large ectatic right coronary artery. Several balloon inflations were performed that were not able to improve distal TIMI flow beyond II. With the intent of vaporizing the remaining thrombus, Excimer Laser Coronary Angioplasty was performed with a favourable outcome.

Discussion

The present case constitutes an opportunity to revisit percutaneous and non-percutaneous strategies to tackle persistent coronary thrombus showing a contemporary approach to niche technologies such as laser angioplasty.

Comparison of the efficacy of excimer laser coronary angioplasty for ST-segment elevation myocardial infarction with onset-to-balloon time

Excimer laser coronary angioplasty (ELCA) vaporizes plaques and thrombi, provides better microcirculation, and reduces peripheral embolism when treating acute coronary syndrome. Studies on the efficacy of ELCA for long onset-to-balloon time ST-segment elevation myocardial infarction (STEMI) are limited. Thus, we aimed to examine the efficacy of ELCA for STEMI using the onset-to-balloon time (OBT). A total of 319 patients with STEMI who underwent percutaneous coronary intervention from 2009 to 2012 and from 2015 to 2019 were enrolled. Patients who underwent PCI in 2009-2012 were considered the conventional group, and those treated with ELCA in 2015-2019 were considered the ELCA group. Patients were stratified by OBT. The endpoints were the final thrombolysis in myocardial infarction (TIMI) grade, myocardial blush grade (MBG), and slow-flow or no-reflow phenomenon during the procedure. The ELCA group had 167 patients, and the conventional group had 123. There was no significant difference in achieving final TIMI 3 between the groups. The acquisition rate of final MBG 3 was significantly higher in the ELCA than in the conventional group (79.6% vs. 65.9%; P = 0.01). There was a significant difference between the groups with OBT 12-72 h (82.1% vs. 56.0%; P = 0.031). The slow- or no-reflow incidence during the procedure was significantly lower in the ELCA than in the conventional group with OBT 12-72 h (17.8% vs. 52.2%; P = 0.019). ELCA improves the MBG and reduces intraoperative slow- or no-reflow phenomenon in patients with STEMI, 12-72 h after onset. ELCA will be useful in preventing peripheral embolism in patients with long onset-to-balloon time STEMI.

Intracoronary thrombus assessment with cardiac computed tomography angiography in a deferred stenting strategy: the MATURE prospective study (MSCT to Assess ThrombUs REsolution)

BACKGROUND

Cardiac computed tomography angiography (CCTA) is precise in noninvasive coronary atherosclerosis characterization but its value in the diagnosis of intracoronary thrombus remains unknown. Therefore, our aim was to evaluate CCTA for intracoronary thrombus and stenosis detection in patients with acute coronary syndromes with high thrombus burden selected for a deferred stenting strategy.

METHODS

We systematically performed a CCTA in consecutive patients following a deferred stenting strategy, 24 h before the scheduled repeated coronary angiography including optical coherence tomography (OCT) imaging. Intracoronary thrombus and residual stenosis were blindly and independently evaluated by both techniques. Agreement was determined per lesion using the weighted Kappa ( K ) coefficient and absolute intraclass correlation coefficient (ICC). A stratified analysis according to OCT-detected thrombus burden was also performed.

RESULTS

Thirty lesions in 28 consecutive patients were analyzed. Concordance between CCTA and repeated coronary angiography in thrombus detection was good ( K  = 0.554; P  < 0.001), but both showed poor agreement with OCT. CCTA needed >11.5% thrombus burden on OCT to obtain adequate diagnostic accuracy. The lesions detected by angiography were more frequently classified as red thrombus (76.5 vs. 33.3%; P  = 0.087) on OCT. CCTA showed an excellent concordance with coronary angiography in diameter measurement (ICC = 0.85; P  < 0.001) and was able to identify all the patients with severe residual stenosis.

CONCLUSIONS

Although CCTA showed just a good concordance with angiography in intracoronary thrombus detection, the agreement in residual stenosis was excellent. Thus, in patients with a high-thrombus burden selected for a deferred stenting strategy CCTA may substitute repeat angiography.

Machine learning assisted reflectance spectral characterisation of coronary thrombi correlates with microvascular injury in patients with ST-segment elevation acute coronary syndrome

Aims

We set out to further develop reflectance spectroscopy for the characterisation and quantification of coronary thrombi. Additionally, we explore the potential of our approach for use as a risk stratification tool by exploring the relation of reflectance spectra to indices of coronary microvascular injury.

Methods and results

We performed hyperspectral imaging of coronary thrombi aspirated from 306 patients presenting with ST-segment elevation acute coronary syndrome (STEACS). Spatially resolved reflected light spectra were analysed using unsupervised machine learning approaches. Invasive [index of coronary microvascular resistance (IMR)] and non-invasive [microvascular obstruction (MVO) at cardiac magnetic resonance imaging] indices of coronary microvascular injury were measured in a sub-cohort of 36 patients. The derived spectral signatures of coronary thrombi were correlated with both invasive and non-invasive indices of coronary microvascular injury. Successful machine-learning-based classification of the various thrombus image components, including differentiation between blood and thrombus, was achieved when classifying the pixel spectra into 11 groups. Fitting of the spectra to basis spectra recorded for separated blood components confirmed excellent correlation with visually inspected thrombi. In the 36 patients who underwent successful thrombectomy, spectral signatures were found to correlate well with the index of microcirculatory resistance and microvascular obstruction; R²: 0.80, p < 0.0001, n = 21 and R²: 0.64, p = 0.02, n = 17, respectively.

Conclusion

Machine learning assisted reflectance spectral analysis can provide a measure of thrombus composition and evaluate coronary microvascular injury in patients with STEACS. Future work will further validate its deployment as a point-of-care diagnostic and risk stratification tool for STEACS care.

Association between kaolin-induced maximum amplitude and slow-flow/no-reflow in ST elevation myocardial infarction patients treated with primary percutaneous coronary intervention

BACKGROUND

ST-segment elevation myocardial infarction (STEMI) patients with a high thrombus burden have a relatively high slow-flow/no-reflow risk. However, the association between kaolin-induced maximum amplitude (MA_thrombin) and slow-flow/no-reflow has been scarcely explored.

METHODS

STEMI patients treated with primary percutaneous coronary intervention (PCI) were retrospectively enrolled from January 2015 to December 2019 at China-Japan Friendship Hospital. MA_thrombin levels were measured using thromboelastography before the PCI procedure. The patients were divided into two groups according to thrombolysis in myocardial infarction (TIMI) flow grade after primary PCI: the normal flow group (TIMI flow grade = 3) and slow-flow/no-reflow (TIMI flow grade ≤ 2). The logistic regression model and restricted cubic spline regression (RCS) were used to analyze the predictive value of MA_thrombin for slow-flow/no-reflow. All patients were followed up after discharge and observed the adverse cardiovascular events between the two groups.

RESULTS

A total of 690 patients were enrolled, with 108(15.7%) having slow-flow/no-reflow. The multivariate logistic regression model analysis showed that MA_thrombin level was an independent risk factor for slow-flow/no-reflow. The RCS analysis showed a nonlinear relationship between MA_thrombin levels and slow-flow/no-reflow. The cut-off value of MA_thrombin levels for predicting slow-flow/no-reflow was 68 mm. During a median follow-up time of 4.4 years, slow-flow/no-reflow (hazard ratio 1.93, 95% confidence interval 1.27-2.93, P = 0.002) and MA_thrombin levels (hazard ratio 1.06, 95% confidence interval 1.03-1.08, P < 0.001) were independent risk factors for predicting the long-term of adverse clinical cardiovascular events.

CONCLUSION

MA_thrombin was an independent risk factor for predicting slow-flow/ no-reflow in STEMI patients who underwent primary PCI.

Enhanced thrombolysis by endovascular low-frequency ultrasound with bifunctional microbubbles in venous thrombosis: in vitro and in vivo study

There is a need to improve the efficacy and safety of endovascular techniques in venous thrombotic diseases, and microbubble enhanced sonothrombolysis is a promising approach. However, whether endovascular low-frequency ultrasound (LFUS) can be utilized in microbubble enhanced sonothrombolysis is unclear. Here, we present a catheter-based thrombolytic system that combines unfocused low-frequency low-intensity ultrasound with novel fibrin-targeted drug-loaded bifunctional microbubbles. We develop an in vitro flow model and an in vivo rabbit inferior vena cava (IVC) thrombosis model to evaluate the safety and efficacy of the thrombolytic system. The results indicate that microbubble enhanced sonothrombolysis with endovascular LFUS treatment for 30 min is equally effective compared to pure pharmacologic treatment. Furthermore, the thrombolytic efficacy of this system is safely and substantially improved by the introduction of a fibrin-targeted drug-loaded bifunctional microbubble with a reduction of the fibrinolytic agent dosage by 60%. The microbubble enhanced endovascular LFUS sonothrombolysis system with excellent thrombolytic efficacy may serve as a new therapeutic approach for venous thrombotic diseases.

Intracoronary pharmacological therapy versus aspiration thrombectomy in STEMI (IPAT-STEMI): A systematic review and meta-analysis of randomized trials

BACKGROUND

Thrombus load in STEMI patients remains a challenge in practice. It aggravates coronary obstruction leading to impaired myocardial perfusion, worsened cardiac function, and adverse clinical outcomes. Various strategies have been advocated to reduce thrombus burden.

OBJECTIVES

This meta-analysis aimed to evaluate the effectiveness of intracoronary-administered thrombolytics or glycoprotein IIb/IIIa inhibitors (GPI) in comparison with aspiration thrombectomy (AT) as an adjunct to percutaneous coronary intervention (PCI) among patients presenting with ST-segment elevation myocardial infarction (STEMI).

METHODS

A comprehensive literature search for randomized trials that compared intracoronary-administered thrombolytics or GPI with AT in STEMI patients who underwent PCI, was conducted using various databases (e.g., MEDLINE, EMBASE, CENTRALE). Primary outcome was procedural measures (e.g., TIMI flow grade 3, TIMI myocardial perfusion grade (TMPG) 3, Myocardial blush grade (MBG) 2/3, ST-segment resolution (STR)).

RESULTS

Twelve randomized trials enrolled 1,466 patients: 696 were randomized to intracoronary-administered pharmacological interventions and 553 to AT. Patients randomized to PCI alone were excluded. Thrombolytics significantly improved TIMI flow grade 3 (odds ratio = 3.71, 95% CI: 1.85-7.45), complete STR (odds ratio = 3.64, 95% CI: 1.60-8.26), and TMPG 3 (odds ratio = 5.31, 95% CI: 2.48-11.36). Thrombolytics significantly reduced major adverse cardiovascular events (MACE) (odds ratio = 0.29, 95% CI: 0.13-0.65) without increasing bleeding risk. Trial sequential analysis assessment confirmed the superiority of thrombolytics for the primary outcome. Intracoronary GPI, either alone or combined with AT, did not improve procedural or clinical outcomes.

CONCLUSIONS

Compared with AT, intracoronary-administered thrombolytics significantly improved myocardial perfusion and MACE in STEMI patients.

Prognostic Role of Residual Thrombus Burden Following Thrombectomy: Insights From the TOTAL Trial

BACKGROUND

It is unclear whether more effective forms of thrombus removal than current aspiration catheters would lead to improved outcomes. We sought to evaluate the prognostic role of residual thrombus burden (rTB), after manual thrombectomy, in patients undergoing primary percutaneous coronary intervention with routine manual thrombectomy in the TOTAL trial (Thrombectomy Versus PCI Alone).

METHODS

This is a single-arm analysis of patients from the TOTAL trial who underwent routine manual aspiration thrombectomy. The rTB was quantified by an angiographic core laboratory using the Thrombolysis in Myocardial Infarction criteria and validated using existing optical coherent tomography data. Large rTB was defined as grade ≥3. The primary outcome was death from cardiovascular causes, recurrent myocardial infarction, cardiogenic shock, or new or worsening heart failure within 180 days.

RESULTS

Of 5033 patients randomized to routine thrombectomy, 2869 patients had quantifiable rTB (1014 [35%] had large rTB). Patients with large rTB were more likely to have hypertension, previous percutaneous coronary intervention, myocardial infarction, or Killip class III on presentation but less likely to have Killip class I. The primary outcome occurred more frequently in patients with large rTB, even after adjustment for known risk predictors (8.6% versus 4.6%; adjusted hazard ratio, 1.83 [95% CI, 1.34-2.48]). These patients also had a higher risk of cardiovascular death (adjusted hazard ratio, 1.83 [95% CI, 1.13-2.95]), cardiogenic shock (adjusted hazard ratio, 2.02 [95% CI, 1.08-3.76]), and heart failure (adjusted hazard ratio, 1.74 [95% CI, 1.02-2.96]) but not myocardial infarction or stroke.

CONCLUSIONS

Large rTB is a common finding in primary percutaneous coronary intervention and is associated with increased risk of adverse cardiovascular outcomes, including cardiovascular death. Future technologies offering better thrombus removal than current devices may decrease or even eliminate the risk associated with rTB. This, potentially, can turn into a strategic option to be studied in clinical trials.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01149044.

Laser vaporization of atherothrombotic burden before drug-coated balloon application in ST-segment elevation myocardial infarction: Two-year outcomes of the laser-DCB trial

OBJECTIVES

This study aimed to examine whether the combination of excimer laser coronary atherectomy (ELCA) and drug-coated balloon (DCB) angioplasty can provide feasible clinical outcome in patients with ST-segment elevation myocardial infarction (STEMI) with 8-month and 2-year scheduled follow-up angiography.

BACKGROUND

Intracoronary thrombus elevates the risk of interventional treatment in patients with STEMI and hampers drug absorption into the vasculature released from DCB.

METHODS

Sixty-two patients with STEMI within 24 h after the onset of symptoms were enrolled in this prospective, single-center, single-arm study.

RESULTS

The laser catheter was successfully crossed distal to the culprit lesion in all cases. No ELCA-related adverse events occurred. Bail-out stenting was required in two patients (3.2%) after adjunctive ballooning; thus, the remaining 60 patients were completed with DCB angioplasty without stenting. Scheduled angiography at 8 months and 2 years was completed in 100% and 85.2%, respectively, and minimal lumen diameters were 3.4 ± 0.5, 3.4 ± 0.6, and 3.4 ± 0.5 mm after the procedure, at 8 months and at 2 years, respectively. Binary restenosis was observed in five patients (8.1%) in whom target lesion revascularization was performed. The duration of dual antiplatelet therapy was 2.3 ± 2.2 months, and neither abrupt vessel closure, reinfarction, cardiac death nor major bleeding was observed.

CONCLUSION

A combination of DCB angioplasty with ELCA is a feasible therapeutic option for STEMI.

Postprocedure Anticoagulation in Patients With Acute ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

OBJECTIVES

This study sought to assess the association between postprocedural anticoagulation (PPAC) use and several clinical outcomes.

BACKGROUND

PPAC after primary percutaneous coronary intervention (pPCI) in patients with ST-segment elevation myocardial infarction (STEMI) may prevent recurrent ischemic events but may increase the risk of bleeding. No consensus has been reached on PPAC use.

METHODS

Using data from the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome registry, conducted between 2014 and 2019, we stratified all STEMI patients who underwent pPCI according to the use of PPAC or not. Inverse probability of treatment weighting and a Cox proportional hazards model with hospital as random effect were used to analyze differences in in-hospital clinical outcomes: the primary efficacy endpoint was mortality and the primary safety endpoint was major bleeding.

RESULTS

Of 34,826 evaluable patients, 26,272 (75.4%) were treated with PPAC and were on average younger, more stable at admission with lower bleeding risk score, more likely to have comorbidities and multivessel disease, and more often treated within 12 hours of symptom onset than those without PPAC. After inverse probability of treatment weighting adjustment for baseline differences, PPAC was associated with significantly reduced risk of in-hospital mortality (0.9% vs 1.8%; HR: 0.62; 95% CI: 0.43-0.89; P < 0.001) and a nonsignificant difference in risk of in-hospital major bleeding (2.5% vs 2.2%; HR: 1.05; 95% CI: 0.83-1.32; P = 0.14).

CONCLUSIONS

PPAC in STEMI patients after pPCI was associated with reduced mortality without increasing major bleeding complications. Dedicated randomized trials with contemporary STEMI management are needed to confirm these findings.

Impact of residual thrombus burden on ventricular deformation after acute myocardial infarction: A sub-analysis from an intravascular optical coherence tomography study

BACKGROUND

Coronary residual thrombus before stenting in ST-segment elevation myocardial infarction (STEMI) has been linked to microvascular injury but its impact on ventricular deformation and cardiac dysfunction in longer term remains unclear.

METHODS

This was a post-hoc sub-analysis from an optical coherence tomography registry. Residual thrombus before stenting was measured geometrically and maximal thrombus-to-lumen area ratio (MTR) was reported. Cardiovascular magnetic resonance (CMR) follow-ups were performed at 30 days post STEMI. The primary outcomes were CMR-derived parameters including left ventricular ejection fraction (LVEF), infarct size, microvascular obstruction (MVO), and left ventricular global strains in radial (GRS), circumferential (GCS), longitudinal (GLS) directions.

FINDINGS

From March 2017 to March 2019, forty-two patients with first-ever anterior STEMI were included. Average CMR follow-up time was 33 (IQR 30-37) days. In multivariable analysis, MTR was significantly associated with LVEF (per 10%, adjusted β = -1·96, 95%CI -3·66 to -0·26), MVO (per 10%, adjusted β = 0·07, 95%CI 0·01 to 0·13), GRS (per 10%, adjusted β = -1·26, 95%CI -2·28 to -0·23), and GCS (per 10%, adjusted β = 0·53, 95%CI 0·01 to 1·06). However, it was not related to GLS (per 10%, adjusted β = 0·29, 95%CI -0·85 to 1·43) or infarct size (per 10%, adjusted β = 0·07, 95%CI -0·40 to 0·55).

INTERPRETATION

Larger residual thrombus burden was associated with worse GRS and GCS but not GLS after a first anterior myocardial infarction.

FUNDING

This work was supported by Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (2016-I2M-1-009), National Natural Science Foundation of China (81,970,308, 81,930,044, and 81,620,108,015), Sanming Project of Medicine in Shenzhen (SZSM201911017), and Shenzhen Key Medical Discipline Construction Fund (No. SZXK001).

Association between serum SCUBE1 levels and thrombus burden in patients with ST-segment elevation myocardial infarction

INTRODUCTION

The signal peptide-CUB-EGF domain-containing protein-1 (SCUBE1) is a recently available biomarker which is expressed by activated and adhered platelets. In present study, we aimed to investigate the association between SCUBE1 levels and thrombus burden in patients with ST elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PPCI).

METHODS

A total of 88 patients who were diagnosed with STEMI and underwent PPCI were prospectively included between July 2019 and August 2019. Blood samples were collected for routine biochemistry and serum SCUBE1 levels before PPCI and antiplatelet therapy. Angiographic coronary thrombus burden was classified based on thrombolysis in myocardial infarction (TIMI) thrombus grades. We formed two groups based on the thrombus grade: 37 (42%) patients had high thrombus burden whereas 51 (58%) patients had low thrombus burden.

RESULTS

The mean age of study population was 58.2 ± 11.8 years (34% female). The mean peak troponin I level, SCUBE1 level, SYNTAX score, and pain-to-balloon time were significantly higher in the high thrombus burden group compared to the low thrombus burden group (p < .05, for all). In ROC analysis, SCUBE1 level >65.63 ng/dL had a sensitivity of 91.9% and a specificity of 76.6% to predict high thrombus burden (AUC: 0.9256; p < .001). In multivariate analysis, SCUBE1 level (HR: 1.133, p = .004) and troponin (HR: 1.002; 95% CI 1.001-1.004, p = .003) were independent predictors of high thrombus burden.

CONCLUSION

In the present study, we showed that SCUBE1, a novel platelet-endothelial adhesion molecule and a marker of platelet activation, is an independent predictor of high thrombus burden in patients with STEMI.

Laser Vaporization of Intracoronary Thrombus and Identifying Plaque Morphology in ST-Segment Elevation Myocardial Infarction as Assessed by Optical Coherence Tomography

Objectives

We evaluated the thrombus-vaporizing effect of excimer laser coronary angioplasty (ELCA) in patients with ST-segment elevation myocardial infarction (STEMI) by optical coherence tomography (OCT).

Background

Larger intracoronary thrombus elevates the risk of interventional treatment and mortality in patients with STEMI.

Methods

A total of 92 patients with STEMI who presented within 24 hours from the onset and underwent ELCA following manual aspiration thrombectomy (MT) were analyzed.

Results

The mean baseline thrombolysis in myocardial infarction flow grade was 0.4 ± 0.6, which subsequently improved to 2.3 ± 0.7 after MT (p < 0.0001) and 2.7 ± 0.5 after ELCA (p=0.0001). The median residual thrombus volume after MT was 65.7 mm³, which significantly reduced to 47.5 mm³ after ELCA (p < 0.0001). Plaque rupture was identified by OCT in only 22 cases (23.9%) after MT, but was distinguishable in 36 additional cases after ELCA (total: 58 cases; 63.0%). Ruptured lesions contained a higher proportion of red thrombus than nonruptured lesions (75.9% vs. 43.3%, p=0.001). Significantly larger thrombus burden after MT (69.6 mm³ vs. 56.3 mm³, p < 0.05) and greater thrombus reduction by ELCA (21.2 mm³ vs. 11.8 mm³, p < 0.01) were observed in ruptured lesions than nonruptured lesions.

Conclusions

ELCA effectively vaporized intracoronary thrombus in patients with STEMI even after MT. Lesions with plaque rupture contained larger thrombus burden that was frequently characterized by red thrombus and more effectively reduced by ELCA.

Micro-CT-Based Quantification of Extracted Thrombus Burden Characteristics and Association With Angiographic Outcomes in Patients With ST-Elevation Myocardial Infarction: The QUEST-STEMI Study

Background: Angiographic detection of thrombus in STEMI is associated with adverse outcomes. However, routine thrombus aspiration failed to demonstrate the anticipated benefit. Hence, management of high coronary thrombus burden remains challenging. We sought to assess for the first time extracted thrombotic material characteristics utilizing micro-computed tomography (micro-CT). Methods: One hundred thirteen STEMI patients undergoing thrombus aspiration were enrolled. Micro-CT was undertaken to quantify retrieved thrombus volume, surface, and density. Correlation of these indices with angiographic and electrocardiographic outcomes was performed. Results: Mean aspirated thrombus volume, surface, and density (±standard deviation) were 15.71 ± 20.10 mm³, 302.89 ± 692.54 mm², and 3139.04 ± 901.88 Hounsfield units, respectively. Aspirated volume and surface were significantly higher (p < 0.001) in patients with higher angiographic thrombus burden. After multivariable analysis, independent predictors for thrombus volume were reference vessel diameter (RVD) (p = 0.011), right coronary artery (RCA) (p = 0.039), and smoking (p = 0.027), whereas RVD (p = 0.018) and RCA (p = 0.019) were predictive for thrombus surface. Thrombus volume and surface were independently associated with distal embolization (p = 0.007 and p = 0.028, respectively), no-reflow phenomenon (p = 0.002 and p = 0.006, respectively), and angiographically evident residual thrombus (p = 0.007 and p = 0.002, respectively). Higher thrombus density was correlated with worse pre-procedural TIMI flow (p < 0.001). Patients with higher aspirated volume and surface developed less ST resolution (p = 0.042 and p = 0.023, respectively). Conclusions: Angiographic outcomes linked with worse prognosis were more frequent among patients with larger extracted thrombus. Despite retrieving larger thrombus load in these patients, current thrombectomy devices fail to deal with thrombotic material adequately. Further studies of novel thrombus aspiration technologies are warranted to improve patient outcomes. Clinical Trial Registration: QUEST-STEMI trial ClinicalTrials.gov number: NCT03429608 Date of registration: February 12, 2018. The study was prospectively registered.

Deferred Stenting for Heavy Thrombus Burden During Percutaneous Coronary Intervention for ST-Elevation MI

Patients with ST-elevation MI (STEMI) usually have a huge thrombus burden in the infarct-related artery. Stenting may lead to high chances of the slow-flow/no-reflow phenomenon that leads to periprocedural MI and adverse cardiovascular events. Deferred stenting may be beneficial in this situation as the thrombus burden will reduce, mitigating the slow-flow/no-reflow phenomenon. However, routine deferral of stenting in patients with STEMI has not been found to be beneficial, but when the patient is properly selected, deferred stenting has the potential for reducing the final infarct size. The authors report the safety and feasibility of deferred stenting after 5 days of prolonged anticoagulation in a 45-year-old smoker with STEMI who had a large thrombus load shown on an angiogram. They review the registries, trials and meta-analyses on deferred stenting in the literature and analyse the benefits and harms of the strategy. They also propose an algorithm for applying a strategy for deferred stenting in clinical practice based on the available data.

Aspiration thrombectomy in ST-Elevation myocardial infarction: Further insights from a network meta-analysis of randomized trials

Background

The initial enthusiasm for thrombectomy during percutaneous coronary intervention (PCI) of ST-elevation myocardial infarction (STEMI) patients has given way to restraint. There has been some limited interest whether it is beneficial in a few selected subgroups. Hence, we performed a network meta-analysis to compare conventional PCI (cPCI), Aspiration or manual thrombectomy (AT) and Mechanical thrombectomy (McT) for clarification.

Methods

Electronic databases were searched for randomized studies that compared AT, McT, or cPCI. A network meta-analysis was performed and odd’s ratio (OR) with 95% confidence intervals was generated for major adverse cardiac events (MACE), mortality, myocardial infarction (MI), target vessel revascularization (TVR), stent thrombosis (ST), stroke, left ventricular ejection fraction (LVEF), myocardial blush grade (MBG) and ST segment resolution (STR).

Results

A total of 43 randomized trials (n = 26,682) were included. The risk of MACE (OR 0.86 95% CI 0.73–1.00), Mortality (OR 0.85 95% CI 0.73–0.99), MI (OR 0.65, 95% CI: 0.44–0.95) and TVR (OR 0.86, 95% CI: 0.74–1.00) were lower with AT compared to cPCI. The risk of ST and stroke was no different with the use of adjunctive AT. MBG, STR, and LVEF improved with the use of AT while the infarct size was no different in the two groups.

Conclusions

Our comprehensive network meta-analysis suggests conflicting outcomes with AT. While Mortality, MACE, MI seem better, there is a suggestion that, Stroke and ST might be worse. Whether AT can still be pursued in any select cases should be further scrutinized.

Excimer Laser Atherectomy in Percutaneous Coronary Intervention: A Contemporary Review

Excimer laser coronary atherectomy (ELCA) during percutaneous coronary intervention (PCI) has been in use for more than twenty years. While early experiences were not favorable over balloon angioplasty alone, with improvement in operator technique, patient selection and technology, ELCA has established its own niche in contemporary PCI as a safe and effective atherectomy strategy. With growing experience in complex coronary interventions worldwide, ELCA has become one of the essential atherectomy tools offering unique advantages over other atherectomy devices. In the modern era, ELCA is commonly used for patients with in-stent restenosis, stent under expansion, balloon uncrossable lesions and chronic total occlusions. Technical success rates are reported to be >80% in most situations while procedural complication rates such as vessel dissection and perforation among others are reported to average 9% over the past 25 years with improvement over time. In this review, we provide a comprehensive systematic review of the ELCA system, its practical use, indications, and procedural techniques in the contemporary PCI era.

MiR-98-5p promotes ischemia/reperfusion-induced microvascular dysfunction by targeting NGF and is a potential biomarker for microvascular reperfusion

OBJECTIVE

This study examined the correlation between serum miR-98-5p levels and indices of microvascular reperfusion in patients undergoing primary percutaneous coronary intervention (pPCI) after ST-segment elevation myocardial infarction (STEMI). Additionally, we evaluated the mechanisms by which miR-98-5p promoted ischemia/reperfusion (I/R)-induced injury in both cultured cell lines and an animal model.

METHODS

Circulating miR-98-5p levels were measured and compared from 171 STEMI patients undergoing pPCI, who were divided into two groups: no-reflow and reflow. The levels of miR-98-5p, nerve growth factor (NGF), and transient receptor potential vanilloid 1 (TRPV1) were analyzed in cultured human coronary endothelial cells (HCECs) exposed to hypoxia/reoxygenation (H/R). The effects of antagomir-98-5p on myocardial I/R-induced microvascular dysfunction in vivo were evaluated. Target gene expression and activity were assessed.

RESULTS

Higher miR-98-5p levels were associated with compromised indices of microvascular reperfusion. In vitro experiments on HCECs showed that exposure to H/R significantly increased miR-98-5p levels. We identified NGF as a novel target of miR-98-5p. Further, antagomir-98-5p relieved microvascular dysfunction and enhanced the expression of NGF and TRPV1 in the rat myocardial I/R model.

CONCLUSIONS

MiR-98-5p promotes microvascular dysfunction by targeting the NGF-TRPV1 axis. Serum miR-98-5p serves as a potential biomarker for microvascular reperfusion.

Provisional drug-coated balloon treatment guided by physiology on de novo coronary lesion

Although drug-eluting stents (DES) have become the mainstay of percutaneous coronary intervention, late and very late stent thrombosis remains a concern. Drug-coated balloons (DCB) have the advantage of preserving the anti-restenotic benefits of DES while minimizing potential long-term safety concerns. Currently the two methods to ensure successful DCB treatment of a stenotic lesion are angiography or physiology-guided DCB application. This review will evaluate these two methods based on previous evidence and make suggestions on how to perform DCB treatment more efficiently and safely.

Clinical Significance of the Presence or Absence of Lipid-Rich Plaque Underneath Intact Fibrous Cap Plaque in Acute Coronary Syndrome

Background Although most coronary thromboses occur on the surface of lipid-rich plaque ( LRP ) with plaque rupture ( PR ), previous pathological and optical coherence tomography studies demonstrated diversity in the morphological characteristics of culprit plaque underlying the thrombus, including lesions with intact fibrous cap ( IFC ). We investigated the clinical significance of IFC in relation to the presence or absence of LRP observed via optical coherence tomography in culprit lesions of acute coronary syndrome. Methods and Results We investigated 510 patients with acute coronary syndrome who underwent optical coherence tomography for the culprit lesion. Optical coherence tomography analysis included the presence or absence of PR , which were categorized into the PR group and the IFC group, respectively. The IFC group was further categorized on the basis of the presence of LRP . Incidence of major adverse cardiac events ( MACEs ), including cardiac death, myocardial infarction, and clinically driven remote revascularizations, was compared. Culprit lesions were categorized into 328 PR s and 182 IFC s. MACEs occurred in 85 patients (16.7%) during the median follow-up duration of 621 days. LRP was detected in 325 lesions (99%) with PR , whereas 60 (33.0%) of the lesions with IFC did not show LRP . Kaplan-Meier analysis revealed significantly lower MACEs in the IFC group compared with the PR group. Furthermore, the IFC group without LRP showed significantly lower MACEs compared with the IFC group with LRP . Multivariate Cox proportional hazards analysis demonstrated that IFC without LRP was an independent predictor of better prognosis. Conclusions Exclusion of LRP underneath IFC culprit lesions in acute coronary syndrome may predict a lower risk of future MACEs .

Residual atherothrombotic burden after primary percutaneous coronary intervention and myocardial reperfusion-An optical frequency domain imaging study

OBJECTIVES

We aimed to assess the relationship between residual in-stent atherothrombotic burden (ATB) after primary percutaneous coronary intervention (PCI) measured by optical frequency domain imaging (OFDI) using different measurement methods and myocardial blush grade (MBG).

BACKGROUND

The impact of residual ATB after primary PCI on myocardial reperfusion remains unclear.

METHODS

We prospectively included 60 ST-elevation myocardial infarction patients pretreated with aspirin and ticagrelor. OFDI volumetric quantification using planimetry (with intervals every frame or every millimeter) and semiquantitative score were used to determine ATB. Patients were divided into two groups according to final MBG 3 or <3.

RESULTS

The mean ATB was 10.08 ± 5.21%. ATB was lower in patients with final MBG 3 compared to those with impaired MBG, regardless of the measurement method (8.15 ± 5.58 vs. 11.77 ± 4.28%; p = .007 for quantification per frame; 7.8 ± 5.19 vs. 11.07 ± 4.07%; p = .009 for quantification per mm and 11.21 ± 11.75 vs. 22.91 ± 17.35; p = .003 for the semiquantitative thrombus score, respectively).

CONCLUSION

Residual post-stenting ATB remains substantial after primary PCI in STEMI patients, even when pretreated with ticagrelor and aspirin. ATB appears as a significant correlate of suboptimal myocardial reperfusion, a known surrogate of clinical outcome.

Intracoronary Optical Coherence Tomography 2018: Current Status and Future Directions

The advent of intravascular imaging has been a significant advancement in visualization of coronary arteries, particularly with optical coherence tomography (OCT) that allows for high-resolution imaging of intraluminal and transmural coronary structures. Accumulating data support a clinical role for OCT in a multitude of clinical scenarios, including assessing the natural history of atherosclerosis and modulating effects of therapies, mechanisms of acute coronary syndromes, mechanistic insights into the effects of novel interventional devices, and optimization of percutaneous coronary intervention. In this state-of-the-art review, we provide an overview of the published data on the clinical utility of OCT, highlighting the areas that need further investigation and the current barriers for further adoption of OCT in interventional cardiology practice.

Plaque erosion versus rupture characterization by optical frequency domain imaging before and after coronary stenting following successful fibrinolysis for ST-segment elevation myocardial infarction

Intracoronary thrombus burden affects the quality of myocardial reperfusion in the setting of ST-elevation myocardial infarction (STEMI). We aimed to study the characteristics of the plaque and thrombus assessed by intracoronary optical frequency domain imaging (OFDI) according to the presence of plaque rupture or erosion in STEMI patients treated with successful fibrinolysis. Pre-stenting thrombus and post-stenting atherothrombotic burden were compared between plaque rupture and erosion. Twenty-seven consecutive patients were included: 17 (63%) had OFDI-plaque rupture and 10 (37%) had OFDI-erosion. Thrombus volume and burden were significantly higher in case of rupture compared to erosion at baseline (13.4 ± 18.4 vs 2.8 ± 2.3 mm³; p = 0.03 and 33.8 ± 17.5 vs 17.5 ± 9.9%; p = 0.007, respectively). In the rupture group, the core of the thrombus consisted dominantly of red thrombus evenly distributed along the entire culprit plaque. In the erosion group, it consisted dominantly of white thrombus with a focal distribution near the minimal lumen area zone. After stenting, the atherothrombotic volume, burden and its distribution, as well as angiographic estimators of myocardial reperfusion were similar between groups. Our study showed that pre-PCI thrombus amount, typesetting and distribution are mainly linked to the underlying mechanism of STEMI. After stenting, the atherothrombotic burden and its distribution were similar between the groups.

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.

Myocardial reperfusion with tirofiban injection via aspiration catheter : Efficacy and safety in STEMI patients with large thrombus burden

BACKGROUND

There is no consensus on the use of thrombus aspiration (TA) in primary percutaneous coronary intervention (PPCI), and few studies have focused on the performance of tirofiban via TA catheter after PPCI. Our study investigated the clinical outcome of tirofiban injection through TA in acute ST-segment elevation myocardial infarction (STEMI) patients with large thrombus burden undergoing PPCI treatment.

PATIENTS AND METHODS

The study comprised 122 STEMI patients who underwent TA during PPCI. Participants were randomly divided into two groups. Group A received intravenous tirofiban injection and tirofiban injection via a TA catheter to the infarcted coronary artery after aspiration (n = 61). Group B received intravenous tirofiban injection only (n = 61). Baseline clinical information and follow-up data were collected for both groups. Coronary angiography, electrocardiography, and echocardiography findings as well as major adverse cardiovascular events (MACE) were recorded.

RESULTS

There were significant differences in postprocedural Thrombolysis in Myocardial Infarction (TIMI) grade 2 and 3 flow between the two groups (p = 0.021, p = 0.006, respectively). The incidence of slow-flow in group A was significantly lower than that of group B (p = 0.011). An increased incidence of no ST-segment resolution was observed in group B (p = 0.011). There were fewer major adverse cardiovascular events in group A than in group B, but the difference was not statistically significant.

CONCLUSION

Selective tirofiban injection via TA catheter during PPCI may improve myocardial reperfusion in STEMI patients with large thrombus burden.

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.

[Deferred versus immediate stenting in patients with ST - segment elevation myocardial infarction and residual large thrombus burden reclassified in the culprit lesion]

BACKGROUND

Reclassification of a large thrombus burden is an independent predictor of major adverse cardiac events and no-reflow in patients with ST- segment elevation myocardial infarction (STEMI). Patients with a greater residual thrombus burden have worse microvascular dysfunction and greater myocardial damage.

METHODS

A retrospective analysis was performed on 833 STEMI patients who underwent primary percutaneous coronary intervention. The final residual thrombus burden was reclassified after the lesion was wired, and a thrombus aspiration or balloon dilatation was performed to restore and stabilise a thrombolysis in myocardial infarction (TIMI) 2-3 flow. Deferred stenting (DEI) was compared with immediate stenting (ISI) group, and the primary outcome was the incidence of no-/slow-reflow (TIMI ≤ 2, or TIMI 3 with myocardial blush grade < 2).

RESULTS

Overall, 47 patients (6.8%) had a residual large thrombus burden reclassified. The right coronary artery was the culprit vessel in 34 cases. More patients had coronary ectasia in the DSI group (P=.005). Fewer patients in the DSI had no-/slow-reflow (36% vs. 58%), and the myocardial blush grade 3 was more frequent in the DSI group (P=.005). After repeat coronary angiography in the DSI group, stenting was not performed in 56%, and oral anticoagulation was more frequent in the follow-up (P=.031). Major cardiac adverse events were similar between groups. There was a tendency to better left ventricular function in the DSI group (P=.056).

CONCLUSIONS

Deferred stenting may be an efficient option in STEMI patients with a residual large thrombus burden reclassified after achieving a stable TIMI 2-3 flow.

Clinical impact of thrombus aspiration on in-hospital mortality in each culprit lesion in the setting of ST-segment elevation myocardial infarction

Recent randomized clinical trials have questioned the clinical benefits of thrombus aspiration (TA) in ST-segment elevation myocardial infarction (STEMI). Real-world data on TA and the efficacy of TA for various culprit lesions have not been sufficiently evaluated. This study mainly aimed to evaluate whether the clinical impact of TA depends on culprit lesions in the setting of STEMI. We surveyed the Tokyo Coronary Care Unit Network Registry, a prospective cohort study, between 2010 and 2014, which included 10,232 patients with STEMI. In-hospital deaths occurred in 538 patients (5.3%). Improved Thrombolysis in Myocardial Infarction flow was more frequently observed in patients who underwent TA than in those who did not (87 vs. 80%; p < 0.001). Univariate logistic regression analysis revealed that TA was associated with a lower in-hospital mortality rate [odds ratio (OR), 0.80; 95% confidential interval (CI), 0.66-0.96; p = 0.016]. However, the difference was not significant after multivariate logistic regression analysis (OR 0.95; 95% CI 0.71-1.17; p = 0.355). Only TA for the left circumflex (LCx) lesions was associated with a better prognosis (OR 0.38; 95% CI 0.21-0.72; p = 0.003). The effect persisted after adjustment (OR 0.50; 95% CI 0.25-0.99; p = 0.049) but was attenuated after analysis using inverse probability weighting (OR 0.97; 95% CI 0.93-0.99; p = 0.048). On the basis of the findings in a large Japanese cohort, a prognostic benefit of TA on in-hospital mortality was not observed. The effect of TA on the LCx lesions was marginally significant and limited. Therefore, TA is not recommended in Japanese patients with STEMI.

Association of Monocyte Count on Admission with the Angiographic Thrombus Burden in Patients with ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Background

The intracoronary high-thrombus burden during the primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction (STEMI) can lead to poor outcomes. Monocytes have been described to play an important role in thrombotic disorders.

Objectives

This study aimed to investigate the relationship between admission monocyte count and angiographic intracoronary thrombus burden in patients receiving primary percutaneous coronary intervention (PPCI).

Methods

A total of 273 patients with acute STEMI who underwent PPCI were enrolled. The patients were divided into two groups according to the thrombolysis in myocardial infarction (TIMI) thrombus grade: low-thrombus burden group with a grade of 0-2 and high-thrombus burden group with a grade of 3-4. The monocyte count and other laboratory parameters were measured on admission before PPCI. P-value < 0.05 was considered significant.

Results

There were 95 patients (34.8%) in the high-thrombus burden group, and 178 patients (65.2%) in the low-thrombus burden group. Patients with high-thrombus burden had significantly higher admission monocyte count (0.61 ± 0.29×10⁹/L vs. 0.53 ± 0.24×10⁹/L, p = 0.021). In multivariate analysis, monocyte count was the independent predictor of angiographic high-thrombus burden (odds ratio 3.107, 95% confidence interval [CI] 1.199-7.052, p = 0.020). For the prediction of angiographic high-thrombus burden, admission monocyte count at a cut-off value of 0.48×10⁹/L yielded 0.59 ROC-AUC (71.9% sensitivity, 46.9% specificity).

Conclusions

Monocyte count on admission was an independent clinical predictor of high-thrombus burden in patients with STEMI undergoing PPCI. Our findings suggest that admission monocyte count may be available for early risk stratification of high-thrombus burden in acute STEMI patients and might allow the optimization of antithrombotic therapy to improve the outcomes of PPCI.

Association Between Prior Aspirin Use and Morphological Features of Culprit Lesions at First Presentation of Acute Coronary Syndrome Assessed by Optical Coherence Tomography

BACKGROUND

The effect of prior use of aspirin (ASA) on the onset of acute coronary syndrome (ACS) has not been clarified. This study used optical coherence tomography (OCT) to investigate the morphological features of culprit lesions of ACS in patients with prior ASA use.Methods and Results:In total, 442 patients with their first ACS episode undergoing OCT for the culprit lesions were investigated. Clinical characteristics, OCT findings, and adverse events at 30 days were compared between patients with prior ASA use and ASA-naïve patients (non-ASA). 67 patients (15.2%) had received ASA at presentation. The ASA group was older, had higher frequency of dyslipidemia and hypertension, and lower renal function than the non-ASA group. Non-ST-elevation ACS was more prevalent in the ASA than in the non-ASA group (79.1 vs. 53.6%, P<0.001). Propensity score matching yielded 49 patients in both groups. OCT revealed less frequent thrombi in the ASA than in the non-ASA group in both the entire (37.3 vs. 75.2%, P<0.001) and score-matched cohorts (38.8 vs. 75.5%, P<0.001), whereas no significant difference was observed in plaque characteristics. Rate of adverse events did not differ between the ASA and the non-ASA groups in the matched cohort.

CONCLUSIONS

With a first ACS presentation, patients with prior ASA use were more likely to present with non-ST-elevation ACS with less frequent intraluminal thrombi, but no significant difference in underlying plaque characteristics or clinical course.