Pathological Characteristics and Classification of Unstable Coronary Atherosclerotic Plaques.

Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart disease, such as acute or chronic myocardial ischemic changes, sometimes make it difficult to locate the ischemic site due to the short death process, the lack of tissue reaction time. In some cases, the deceased died of sudden death on the first-episode, resulting in difficulty for medical examiners to make an accurate diagnosis. However, clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process. This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medical research, including plaque rupture, plaque erosion and calcified nodules, as well as the influencing factors leading to plaque instability, and briefly describes the research progress and technique of the atherosclerotic plaques, in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different pathologic states of coronary atherosclerotic plaques.

Lipoprotein(a) Is Associated with Thrombus Burden in Culprit Arteries of Younger Patients with ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Lipoprotein(a) (Lp[a]) is a risk factor for cardiovascular disease. The burden of thrombus in ST-segment elevation myocardial infarction (STEMI) has implications on treatment and outcomes. However, the association between Lp(a) and atherothrombosis in STEMI remains unclear. OBJECTIVES: The aim of the study was to determine the association between Lp(a) and culprit artery thrombus burden in younger patients with STEMI. METHODS: This was a single-center study of 83 patients aged <65 years with STEMI between 2016-2018 who underwent percutaneous coronary intervention and measurement of Lp(a); those receiving thrombolytic therapy were excluded. Thrombus burden in the culprit artery was determined angiographically using the Thrombolysis In Myocardial Infarction score and classified as absent-to-small, moderate, or large. Elevated Lp(a) was defined as plasma mass concentration >30 mg/dL. Multivariate analysis was performed adjusting for cardiovascular risk factors. RESULTS: The mean age was 48.0 ± 8.4 years, and 78.3% were male. Thirteen (16%), 9 (11%), and 61 (73%) patients had small, moderate, or large thrombus burden, respectively, and 34 (41%) had elevated Lp(a). Elevated Lp(a) was associated with greater thrombus burden compared to normal Lp(a) (large burden 85% vs. 65%; p = 0.024). Elevated Lp(a) was associated with moderate or large thrombus in univariate (OR 10.70 [95% CI 1.32-86.82]; p = 0.026) and multivariate analysis (OR 10.33 [95% CI 1.19-89.52]; p = 0.034). Lp(a) was not associated with culprit artery or stenosis location according to culprit artery. CONCLUSIONS: Elevated Lp(a) is associated with greater thrombus burden in younger patients with STEMI. The finding of this observational study accords with the thrombotic and anti-fibrinolytic properties of Lp(a). A causal relationship requires verification.

Simultaneous Double-Vessel Coronary Thrombosis with Sudden Cardiac Arrest as the First Manifestation of COVID-19.

The relationship between coronavirus disease 2019 (COVID-19) and myocardial injury was established at the onset of the COVID-19 pandemic. An increase in the incidence of out-of-hospital cardiac arrest was also observed. This case report aims to point to the prothrombotic and proinflammatory nature of coronavirus infection, leading to simultaneous coronary vessel thrombosis and subsequently to out-of-hospital cardiac arrest. During the COVID-19 pandemic, a 46-year-old male patient with no comorbidities suffered out-of-hospital cardiac arrest (OHCA) with ventricular fibrillation as the first recorded rhythm. The applied cardiopulmonary resuscitation (CPR) measures initiated by bystanders and continued by emergency medical service (EMS) resulted in the return of spontaneous circulation. The stabilized patient was transferred to the tertiary university center. Electrocardiogram (ECG) revealed "lambda-like" ST-segment elevation in DI and aVL leads, necessitating an immediate coronary angiography, which demonstrated simultaneous occlusion of the left anterior descending (LAD) and right coronary artery (RCA). Primary percutaneous coronary intervention (PCI) with the implantation of one drug-eluting stent (DES) in LAD and two DES in RCA was done. Due to the presence of cardiogenic shock (SCAI C), an intra-aortic balloon pump (IABP) was implanted during the procedure, and due to the comatose state and shockable cardiac arrest, targeted temperature management was initiated. The baseline chest X-ray revealed bilateral interstitial infiltrates, followed by increased proinflammatory markers and a positive polymerase chain reaction (PCR) test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) demasking underlying COVID-19-related pneumonia. Within the following 48 h, the patient was hemodynamically stable, which enabled weaning from IABP and vasopressor discontinuation. However, due to the worsening of COVID-19 pneumonia, prolonged mechanical ventilation, together with antibiotics and other supportive measures, was needed. The applied therapy resulted in clinical improvement, and the patient was extubated and finally discharged on Day 26, with no neurological sequelae and with mildly reduced left ventricle ejection fraction.

Acute myocardial infarction with simultaneous total occlusion of the left anterior descending artery and right coronary artery successfully treated with percutaneous coronary intervention.

BACKGROUND: Simultaneous thrombosis in more than one coronary artery is an uncommon angiographic finding in patients with acute ST-segment elevation myocardial infarction. It is difficult to identify using 12-lead electrocardiography and usually leads to cardiogenic shock and fatal outcomes, including sudden cardiac death. Therefore, immediate revascularization and adequate mechanical circulatory support are required. CASE PRESENTATION: We report the case of a 58-year-old man who presented with vomiting and chest pain complicated by cardiogenic shock and complete atrioventricular block. Electrocardiography revealed ST-segment elevation in leads II, III, aVF, and V1-V6. Emergency coronary angiography revealed total occlusion of the proximal left anterior descending artery and right coronary artery. The patient successfully underwent primary percutaneous coronary intervention with ballooning and stenting for both arteries. An Impella CP was inserted during the procedure. Fifty-seven days after admission, he had New York Heart Association class II heart failure and was transferred to a rehabilitation hospital. CONCLUSIONS: Acute double-vessel coronary thrombosis, a serious event with a high mortality rate, requires prompt diagnosis and management to prevent complications such as cardiogenic shock and ventricular arrhythmias. A combination of judicious medical treatment, efficient primary percutaneous coronary intervention, and early mechanical support device insertion is crucial to improve the survival rate of patients with this disease.

Impact of thrombus burden on long-term clinical outcomes in patients with either anterior or non-anterior ST-segment elevation myocardial infarction.

Large thrombus burden (LTB) during ST-segment elevation myocardial infarction (STEMI) could translate into worse clinical outcomes. The impact of a LTB in terms of long-term clinical outcomes on different myocardial infarct territories has not yet been fully evaluated. From April 2002 to December 2004, consecutive patients with STEMI undergoing percutaneous coronary intervention with drug eluting stent were evaluated. The study sample was stratified in two groups: anterior STEMI and non-anterior STEMI. LTB was considered as a thrombus larger than or equal to 2-vessel diameters, and small thrombus burden less than 2-vessel diameters. Major adverse cardiac events (MACE) were evaluated at 10-year and survival data were collected up to 15-year. A total of 812 patients were evaluated, 6 patients were excluded due to inadequate angiographic images, 410 (50.9%) had an anterior STEMI and 396 (49.1%) a non-anterior STEMI. Patients with LTB had higher rates of 10-year mortality (aHR 2.27, 95%CI 1.42-3.63; p = 0.001) and 10-year MACE (aHR 1.46, 95%CI 1.03-2.08; p = 0.033) in anterior STEMI, but not in non-anterior STEMI (aHR 0.78, 95%CI 0.49-1.24; p = 0.298; aHR 0.71, 95%CI 0.50-1.02; p = 0.062). LTB was associated with increased 30-day mortality (aHR 5.60, 95%CI 2.49-12.61; p < 0.001) and 30-day MACE (aHR 2.72, 95%CI 1.45-5.08; p = 0.002) in anterior STEMI, but not in non-anterior STEMI (aHR 0.39, 95%CI 0.15-1.06; p = 0.066; aHR 0.67, 95%CI 0.31-1.46; p = 0.316). Beyond 30-day, LTB had no impact on mortality and MACE in both groups. In anterior STEMI, LTB is associated with worse long-term clinical outcomes, this effect was driven by early events.

Nonatrial Fibrillation Patients With Complete P Wave Disappearance: An Overlooked Population With High Stroke Risk.

BACKGROUND AND PURPOSE: Complete P wave disappearance (CPWD) in patients without atrial fibrillation is an uncommon clinical phenomenon. We aimed to study the relationship between CPWD and thromboembolism. METHODS: Between July 2007 and December 2018, consecutive patients with CPWD on surface ECG and 24-hour Holter recording were recruited into the study from 4 centers in China. All recruited patients underwent transesophageal echocardiography or cardiac computed tomography to screen for atrial thrombus. Atrial electrical activity and scar were assessed by electrophysiological study (EPS) and 3-dimensional electroanatomic mapping. Cardiac structure and function were assessed by multimodality cardiac imaging. RESULTS: Twenty-three consecutive patients (8 male; mean age 48.5±14.7 years) with CPWD were included. Only 3 patients demonstrated complete atrial electrical silence with atrial noncapture. Thirteen patients who had invasive atrial endocardial mapping demonstrated extensive scar. Pulse-wave mitral inflow Doppler demonstrated absent and dampened A waves in 18 and 5 patients, respectively. Pulse-wave tricuspid inflow Doppler showed absent and dampened A waves in 19 and 4 patients, respectively. Upon recruitment, 8 patients had previous stroke and 3 patients had atrial thrombus. Warfarin was prescribed to all patients. During median follow-up of 42.0 months, 2 patients developed massive ischemic stroke due to warfarin discontinuation. CONCLUSIONS: Our study suggested that CPWD reflects extensive atrial electrical silence and significantly impaired atrial mechanical function. It was strongly associated with thromboembolism and the clinical triad of CPWD-atrial paralysis-stroke was proposed. Anticoagulation should be recommended in such patients.

FIP1L1-PDGFRA-Associated Hypereosinophilic Syndrome as a Treatable Cause of Watershed Infarction.

Background and Purpose: Ischemic stroke has been reported in various conditions associated with eosinophilia. FIP1L1-PDGFRA fusion ([Fip1-like 1-platelet-derived growth factor receptor alpha]; F/P) leads to the proliferation of the eosinophilic lineage and thus to a clonal hypereosinophilic syndrome that is highly responsive to imatinib. Methods: We previously reported on a nationwide retrospective study of 151 patients with F/P-associated clonal hypereosinophilic syndrome. Patients from this cohort with a clinical history of ischemic stroke (as well as 2 additional cases) were further analyzed to better define their clinical picture and outcomes. Results: Sixteen male patients (median age, 51 [43­59] years) with low-to-intermediate cardiovascular risk were included. Median National Institutes of Health Stroke Scale was 4 (range, 1­6). Most cerebral imaging disclosed multiple bilateral infarctions of watershed distribution (69%). Despite frequent cardiac involvement (50%), cardiac thrombus was evidenced in a single patient and, according to the TOAST classification (Trial of ORG 10172 in Acute Stroke Treatment), 62.5% of strokes were presumably of undetermined etiology. Among the 15 patients treated with imatinib, and after a median follow-up of 4.5 years, stroke recurred in only 3 patients (consisting of either cardio embolic or hemorrhagic events, unrelated to the first episode). Conclusions: F/P+ clonal hypereosinophilic syndrome is a diagnosis to consider in patients with unexplained ischemic stroke and hypereosinophilia (especially in the setting of multiple cortical borderzone distribution) and warrants prompt initiation of imatinib.

COVID-19 complicated by acute myocardial infarction with extensive thrombus burden and cardiogenic shock.

A patient with coronavirus disease 19 (COVID-19) developed acute myocardial infarction (AMI) complicated by extensive coronary thrombosis and cardiogenic shock. She underwent percutaneous coronary intervention and placement of a mechanical circulatory support device but subsequently died from shock. This report illustrates the challenges in managing patients with COVID-19, AMI, and cardiogenic shock.

Degree of luminal narrowing and composition of thrombus in plaque erosion.

As the degree of luminal narrowing increases, shear stress increases, and high shear stress is known to activate platelets. However, the relationship between the degree of luminal narrowing and the composition of thrombus in patients with plaque erosion has not been studied. A total of 148 patients with plaque erosion and thrombus detected by optical coherence tomography were divided into tertiles based on the minimum lumen area (MLA) at the culprit lesion. Thrombus was categorized as platelet-rich or fibrin-rich. Among 148 patients, 50 (34%) were in the mild stenosis group, 49 (33%) were in the moderate stenosis group, and 49 (33%) were in the severe stenosis group. The composition of thrombus was significantly different among the 3 groups (prevalence of platelet-rich thrombus was 60% in the mild stenosis group; 78% in the moderate stenosis group; and 84% in the severe stenosis group; P = 0.021). The pattern of fibrin-rich thrombus showed the opposite: 40%, 22%, and 16%, respectively. In the multivariate analysis, current smoking was independently associated with fibrin-rich thrombus (odds ratio [OR] 2.364 [95% CI 1.004-5.567], P = 0.049). This study demonstrated that platelet-rich thrombus was the predominant type of thrombus in plaque erosion. The prevalence of fibrin-rich thrombus was highest in the mild stenosis group.

Undiagnosed Cardiac Sarcoidosis Causing Refractory Heart Failure After Acute Myocardial Infarction due to Thromboembolism.

A 61-year-old woman suffered chest pain and was admitted to a nearby hospital emergency department. She was diagnosed with acute myocardial infarction probably due to thromboembolism in the left anterior descending coronary artery and aspiration thrombectomy was performed. Afterwards, she developed refractory heart failure with severe global left ventricular dysfunction and was transferred to our hospital. An 18F-FDG-PET/CT scan revealed abnormal 18F-FDG uptake in non-infarcted regions of the left ventricle. Non-caseating granulomas were detected by biopsy from a skin eruption. She was diagnosed with cardiac sarcoidosis. In cases of refractory heart failure which cannot be explained only by myocardial infarction, evaluation of other undiagnosed cardiomyopathies is important for optimal management.

Life after abciximab; what's next for intracoronary thrombus?

A case is described in which the short-acting glycoprotein IIb/IIIa receptor antagonist tirofiban was used in combination with heparin, aspirin and prasugrel to successfully treat extensive intracoronary thrombus in a delayed presentation STEMI, illustrating the utility of this approach.

Evaluation of an in vitro coronary stent thrombosis model for preclinical assessment.

Stent thrombosis remains an infrequent but significant complication following percutaneous coronary intervention. Preclinical models to rapidly screen and validate therapeutic compounds for efficacy are lacking. Herein, we describe a reproducible, high throughput and cost-effective method to evaluate candidate therapeutics and devices for either treatment or propensity to develop stent thrombosis in an in vitro bench-top model. Increasing degree of stent malapposition (0.00 mm, 0.10 mm, 0.25 mm and 0.50 mm) was associated with increasing thrombosis and luminal area occlusion (4.1 ± 0.5%, 6.3 ± 0.5%, 19.7 ± 4.5%, and 92.6 ± 7.4%, p < 0.0001, respectively). Differences in stent design in the form of bare-metal, drug-eluting, and bioresorbable vascular scaffolds demonstrated differences in stent thrombus burden (14.7 ± 3.8% vs. 20.5 ± 3.1% vs. 86.8 ± 5.3%, p < 0.01, respectively). Finally, thrombus burden was significantly reduced when healthy blood samples were incubated with Heparin, ASA/Ticagrelor (DAPT), and Heparin+DAPT compared to control (DMSO) at 4.1 ± 0.6%, 6.9 ± 1.7%, 4.5 ± 1.2%, and 12.1 ± 1.8%, respectively (p < 0.01). The reported model produces high throughput reproducible thrombosis results across a spectrum of antithrombotic agents, stent design, and degrees of apposition. Importantly, performance recapitulates clinical observations of antiplatelet/antithrombotic regimens as well as device and deployment characteristics. Accordingly, this model may serve as a screening tool for candidate therapies in preclinical evaluation.

The combined use of stent retriever and neuro-aspiration as successful bail-out reperfusion strategy in a patient with embolic myocardial infarction.

Embolic myocardial infarction account for ≈3% of all ST-segment myocardial infarction and represents a challenge often left no-reperfused because current thrombectomy technologies are inefficient to grab thrombus wedged into distal coronary arteries. We present the case of a 34-year-old man who presented with anterior STEMI and a proximal left anterior descending coronary artery ulcerated plaque with a great thrombus burden, which led to distal embolization. Failure of several attempts of manual and rheolytic thrombectomy, led us to use the "Solumbra technique", the combined use of stent retriever and Penumbra catheter was successful in restoring patency and flow.

Antiplatelet Therapy Bridging With Cangrelor in Patients With Coronary Stents: A Case Series.

BACKGROUND: Cangrelor is an intravenous P2Y12 receptor antagonist approved for use during percutaneous coronary intervention (PCI) to reduce ischemic events associated with new stent placement and has been used off-label at reduced doses guided by platelet function testing as a "bridge" from discontinuation of oral P2Y12 receptor antagonists to surgical procedures when the long-term effects of oral agents are undesirable. OBJECTIVE: To describe the dosing, laboratory monitoring, and clinical outcomes of a series of patients who received cangrelor as a "bridging" antiplatelet agent. METHODS: This study is a retrospective analysis of all patients within the study center with coronary stents who received cangrelor as a bridge to surgical procedure and had VerifyNow monitoring during treatment. RESULTS: A total of 11 patients were identified for inclusion. The median cangrelor dose was 0.5 µg/kg/min (interquartile range = 0.5-0.5) and was maintained in 7 of 11 patients. Doses ranged from 0.25 to 2 µg/kg/min during therapy, and 81.6% of VerifyNow results assessed were within goal range (⩽208 P2Y12 reaction units). Bleeding complications during therapy occurred in 3 patients, all of whom were receiving concomitant heparin infusions, and no stent thrombosis was reported. Conclusion and Relevance: Low-dose cangrelor may represent an effective option for bridging antiplatelet therapy in patients with coronary stents. This study demonstrated that the majority of patients received adequate platelet inhibition without any incidence of stent thrombosis on 0.5 µg/kg/min using the VerifyNow assay to monitor platelet inhibition, which represents a lower dose than previously reported in the literature.

Intracardiac mass in chronic myeloid leukemia.

Chronic myeloid leukaemia (CML) is a neoplastic disorder of myeloid cell lines and is a less aggressive disease compared to acute myeloid leukemia (AML). Although cardiovascular complications are not uncommon, intracardiac thrombosis in CML is rarely reported. Herein, we report a case of CML presenting with an intracardiac thrombus attached to the posterior mitral leaflet, and subsequently resulting in peripheral embolization.

Coronary microvascular dysfunction is associated with cardiac time intervals in women with angina and no obstructive coronary artery disease: An iPOWER substudy.

BACKGROUND: Coronary microvascular dysfunction (CMD) may cause angina in the absence of obstructive coronary artery disease (CAD) and increases the risk of future adverse cardiovascular events. Transthoracic Doppler echocardiography (TTDE) with pharmacological stress can assess coronary flow velocity reserve (CFVR), a measure of coronary microvascular function. However, simpler methods would be preferable for diagnosing CMD. Therefore, we examined the relationship between CFVR and cardiac time intervals measured by TTDE in a cohort of women with angina and no obstructive CAD. METHODS: In a prospective cohort study, we included 389 women with angina, left ventricular ejection fraction > 45%, and no obstructive CAD. CMD was defined as CFVR < 2.0. The study population was divided into three groups according to cutoff values of CFVR < 2, 2 ≤ CFVR ≤ 2.5, and CFVR > 2.5. Isovolumic contraction time (IVCT), ejection time (ET), and isovolumic relaxation time (IVRT) were measured by tissue Doppler M-mode, and the myocardial performance index (MPI = (IVCT + IVRT)/ET) was calculated. RESULTS: Coronary microvascular dysfunction was associated with increasing age, hypertension, higher resting heart rate, and lower diastolic blood pressure. Moreover, CMD was associated with higher E/e' ratio (P = 0.002) and longer IVCT (P < 0.001), higher MPI (P < 0.001) and shorter ET (P = 0.002), but not with IVRT or conventional measures of left ventricular geometry, mass, and function. In multivariable analysis, longer IVCT (P < 0.001) and higher MPI (P = 0.002) remained associated with CMD. CONCLUSION: In women with angina and no obstructive CAD, CMD is associated with longer IVCT and higher MPI indicating a link between CMD and subtle alternations of systolic and combined measures of cardiac time intervals.

In ST-segment elevation myocardial infarction, the echocardiographic parameters of microvascular obstruction are not associated with left ventricular remodeling at five years of follow-up.

OBJECTIVE: The correlation between the echocardiographic Doppler flow parameters of microvascular obstruction (MVO) and coronary wedge pressure (CWP) measured as a marker of severe compressive microvascular dysfunction and a predictor of adverse left ventricular remodeling was evaluated in a group of high-risk acute anterior myocardial infarction survivors. METHODS: Twenty-four patients with mechanically reperfused anterior STEMI were divided into two groups based on the 38 mm Hg CWP cutoff for adverse left ventricular remodeling. Diastolic deceleration time (DDT), coronary flow reserve (CFR), systolic retrograde flow, peak systolic and peak diastolic velocities in the infarct-related artery were determined 3-5 days after revascularization. An echocardiographic 20% increase in left ventricular volumes defined adverse remodeling. RESULTS: No significant differences were recorded between groups with regard to the echocardiographic parameters of MVO. No significant correlation was identified between CWP on one side and DDT (P = 0.30) and CFR (P = 0.39) on the other, irrespective of total ischemic time and extracted thrombus length. No difference in 5 years of follow-up left ventricular remodeling was detected in patients with DDT<900 msec as compared to those with DDT≥900 msec. The medium increase in left ventricular end-systolic volume in patients with low CWP was 24.78%, while it reached 127.27% (P = 0.03) in patients with CWP>38 mm Hg. CONCLUSIONS: Coronary wedge pressure did not correlate with the surrogate parameters for MVO, but it was a predictor of left ventricular remodeling. None of the echocardiographic MVO parameters was associated with adverse remodeling at 5 years of follow-up.

Takotsubo cardiomyopathy in a man with no trigger and multiple cardioembolic complications-A rare constellation.

Takotsubo Cardiomyopathy (TC) is an uncommon, transient, reversible cardiomyopathy, with a classic pattern of wall-motion abnormalities, usually seen in women after an emotional stressor. Despite its increased recognition, there remain gaps in the exact mechanisms, predisposing factors, and predictors of recovery; this is particularly true for males where the condition occurs far less frequently than in females. TC typically resolves within weeks, and the prognosis is favorable compared to acute coronary syndromes. Nonetheless, about 1% of cases may be complicated by left ventricular (LV) thrombus and embolism. Herein we describe an atypical case of a man with no obvious trigger, who developed TC with left ventricular thrombus and multiple embolic complications, but subsequently showed complete and full resolution. Multimodality imaging including echocardiography, cardiac CT and cardiac MRI was instrumental in this diagnostic dilemma, as well as useful in guiding treatment options and informing prognosis.

Randomized trial of primary PCI with or without routine manual thrombectomy.

BACKGROUND: During primary percutaneous coronary intervention (PCI), manual thrombectomy may reduce distal embolization and thus improve microvascular perfusion. Small trials have suggested that thrombectomy improves surrogate and clinical outcomes, but a larger trial has reported conflicting results. METHODS: We randomly assigned 10,732 patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI to a strategy of routine upfront manual thrombectomy versus PCI alone. The primary outcome was a composite of death from cardiovascular causes, recurrent myocardial infarction, cardiogenic shock, or New York Heart Association (NYHA) class IV heart failure within 180 days. The key safety outcome was stroke within 30 days. RESULTS: The primary outcome occurred in 347 of 5033 patients (6.9%) in the thrombectomy group versus 351 of 5030 patients (7.0%) in the PCI-alone group (hazard ratio in the thrombectomy group, 0.99; 95% confidence interval [CI], 0.85 to 1.15; P=0.86). The rates of cardiovascular death (3.1% with thrombectomy vs. 3.5% with PCI alone; hazard ratio, 0.90; 95% CI, 0.73 to 1.12; P=0.34) and the primary outcome plus stent thrombosis or target-vessel revascularization (9.9% vs. 9.8%; hazard ratio, 1.00; 95% CI, 0.89 to 1.14; P=0.95) were also similar. Stroke within 30 days occurred in 33 patients (0.7%) in the thrombectomy group versus 16 patients (0.3%) in the PCI-alone group (hazard ratio, 2.06; 95% CI, 1.13 to 3.75; P=0.02). CONCLUSIONS: In patients with STEMI who were undergoing primary PCI, routine manual thrombectomy, as compared with PCI alone, did not reduce the risk of cardiovascular death, recurrent myocardial infarction, cardiogenic shock, or NYHA class IV heart failure within 180 days but was associated with an increased rate of stroke within 30 days. (Funded by Medtronic and the Canadian Institutes of Health Research; TOTAL ClinicalTrials.gov number, NCT01149044.).