Acute Thrombus Research Articles

Lower extremity deep vein thrombosis: an ultrasound revisit regarding its diagnostic value

Aim: To determine the diagnostic value of ultrasound in lower extremity deep vein thrombosis (LEDVT). Methods: Data of 20 patients diagnosed with LEDVT and underwent endovascular treatment at Hue University of Medicine and Pharmacy hospital from 01/2021 - 08/2022 were analyzed. Ultrasound findings were documented and correlated with venography. All patients were initialized with anticoagulation upon the diagnosis of LEDVT. Endovascular treatment included diagnostic venography, inferior vena cava filter insertion, intraclot thrombolysis, manual thromboaspiration with or without venoplasty and stenting. Results: The mean age was 58.63 ± 16.9 (range, 17 - 85 age). The major risk factors were trauma, surgery, and a history of DVT. LEDVT was found prominently in the left leg and at the femoropopliteal level. Ultrasound had a sensitivity of 93.6%, a specificity of 97.6%, a positive predictive value of 98.6%, a negative predictive value of 89.1% and accuracy of 95% in the diagnosis of LEDVT. The sensitivity and specificity of ultrasound in differentiating between chronic and acute thrombus were 96.5% and 92%. Ultrasound had low sensitivity in evaluating collaterals and venous outflow obstruction (May-Thurner syndrome). Conclusion: Ultrasound has a high diagnostic value and remains the first line imaging modality in the investigation of LEDVT. Key words: deep vein thrombosis; ultrasound; venography; thromboaspiration; May-Thurner syndrome

Scary Acute Left Main Coronary Artery Thrombus as an Initial Presentation of a Hereditary Thrombophilia: When to Go Out of Routine?

Patients with either hereditary or acquired thrombophilia can present with arterial and venous thrombotic complications. However, it is unclear to whom the thrombophilia panel should be assessed, particularly in patients presenting with a common cardiovascular risk factor and acute coronary thrombus. Herein, we presented the management of an active smoker female patient who presented to our emergency room with inferior acute ST-segment elevation myocardial infarction, and hereditary thrombophilia has been diagnosed due to the presence of substantial left main coronary artery thrombus.

Single-Center Experience in Managing Right Liver Grafts From Trifurcation or Independent Right Posterior Portal Vein in Adult Living Donor Liver Transplantation

The right liver graft has sometimes been from the trifurcation portal vein (TPV) or independent right posterior portal vein (IRPPV). Managing these PV anatomies to increase the recipient's survival rate remains challenging. Many published techniques could overcome this problem, such as simple unification venoplasty (SUV), autologous portal Y-graft interposition, conjoined unification venoplasty (CUV) with a baseball-like conduit, and SUV plus circumferential fence-like vein extension. This study reviewed our strategy for managing the right liver grafts from TPV or IRPPV in adult living donor liver transplantation (aLDLT). We enrolled the study population who underwent aLDLT using the grafts with TPV or IRPPV at our institute from October 2004 to October 2022. We analyzed the reconstruction methods for these grafts and postoperative PV complications in donors and recipients. During the study period, of 528 aLDLT recipients, we identified 26 donors with TPV (n=10) or IRPPV (n=16). Eight grafts from TPV had a single PV orifice. The other 18 grafts had dual right PVs that underwent initial PV management, including SUV (n=13), recipient's right and left portal veins to graft's dual PVs (n=2), Y-graft interposition (n=1), CUV (n=1) and SUV with fence-like vein extension (n=1). One SUV graft changed to fence venoplasty due to significant tension for PV anastomosis. The acute right posterior PV thrombus and anterior PV stenosis happened in 2 cases with Y-graft interposition and native PVs direct anastomosis. One donor with TPV had portal vein thrombosis and needed thrombectomy with vein patch repair. The graft from TPV should be carefully planned. A single PV orifice may be feasible but not always possible. An SUV could cover most IRPPVs, but if the distance between the right anterior and posterior PVs is a problem, CUV would be an alternative method. In addition, SUVs with fence venoplasty could relieve PV anastomosis tension.

Six-Month Deep Vein Thrombosis Outcomes by Chronicity: Analysis of the Real-World ClotTriever Outcomes Registry

PurposeTo analyze the first 250 patients from the prospective, multicenter, industry-sponsored ClotTriever Outcomes (CLOUT) registry, assessing the safety and effectiveness of mechanical thrombectomy for acute, subacute, and chronic deep vein thrombosis (DVT). Materials and MethodsReal-world patients with lower extremity DVT were treated with the ClotTriever System (Inari Medical, Irvine, California). Adjuvant venoplasty, stent placement, or both were performed at the physician’s discretion. Thrombus chronicity was determined by visual inspection of removed thrombus, categorizing patients into acute, subacute, and chronic subgroups. Serious adverse events (SAEs) were assessed through 30 days. Clinical and quality-of-life (QoL) outcomes are reported through 6 months. ResultsThrombus chronicity was designated for 244 of the 250 patients (acute, 32.8%; subacute, 34.8%; chronic, 32.4%) encompassing 254 treated limbs. Complete or near-complete (≥75%) thrombus removal was achieved in 90.8%, 81.9%, and 83.8% of the limbs with acute, subacute, and chronic thrombus, respectively. No fibrinolytics were administered, and 243 (99.6%) procedures were single sessions. One (0.4%) patient in the subacute group experienced a device-related SAE, a fatal pulmonary embolism. On comparing baseline and 6-month data, improvements were demonstrated in median Villalta scores (acute, from 10 to 1; subacute, from 9 to 1; chronic, from 10 to 3; for all, P < .0001) and mean EuroQol group 5-dimension (EQ-5D) self-report questionnaire scores (acute, 0.58 to 0.89; subacute, 0.65 to 0.87; chronic, 0.58 to 0.88; for all, P < .0001). There were no significant differences in outcomes across the subgroups. ConclusionsMechanical thrombectomy using the ClotTriever System with adjunctive venoplasty and stent placement is safe and similarly effective for acute, subacute, and chronic DVT.

Spatial Proteomics Analysis of Soft and Stiff Regions in Human Acute Arterial Thrombus.

The soft regions of a thrombus tend to be more susceptible to r-tPA (recombinant tissue-type plasminogen activator)-mediated thrombolysis and are more easily removed by mechanical thrombectomy than the stiff counterpart. This study aimed to understand the molecular pathological differences between the soft and stiff regions of human arterial thrombus. We developed a spatial proteomic workflow combining proteomics with laser-captured microdissection to analyze human arterial thrombi with Masson trichrome staining to identify stiff and soft regions from 2 independent cohorts of patients with acute myocardial or cerebral infarction. Dysregulated proteins in a C57BL6/J male mouse model of arterial thrombosis were identified by pathway enrichment and pairwise analyses from the common gene ontology enrichment and dysregulated proteins between carotid and coronary arterial thrombi, and validated by immunohistochemistry. Spatial proteomics of the coronary arterial thrombi collected from 7 patients with myocardial infarct revealed 7 common dysregulated proteins in 2 cohorts of patients, and upregulation of TGF-β1 (transforming growth factor β1) was the most prominent fibrosis-related protein. Inhibition of TGF-β1 resulted in delayed arterial thrombosis and accelerated blood flow restoration in mouse model. We further expanded the spatial proteomic workflow to the carotid artery thrombi collected from 11 patients with cerebral infarction. Pairwise proteomic analysis of stiff and soft regions between carotid and coronary arterial thrombi further revealed 5 common gene ontology clusters including features of platelet activation, and a common dysregulated protein COL1A1 (collagen type 1 alpha 1) that was reported to be influenced by TGF-β1. We also verified the expression in human and mice carotid arterial thrombi. This study demonstrates the spatially distinct composition of proteins in the stiff and soft regions of human arterial thrombi, and suggests that TGF-β1 is a key therapeutic target for promoting arterial thrombolysis.

Endovascular Repair of Iatrogenic Inferior Vena Cava and Iliac Vein Injury: A Case Series and Review of the Literature.

Iatrogenic injury to the large abdominopelvic veins can he highly morbid, and open surgical repair is technically challenging. Endovascular repair with covered stenting across the injured segment offers an alternative to open surgical management. We present a series of patients with operative injury to the inferior vena cava (IVC) and iliac veins who were treated utilizing an endovascular approach and review the available literature on this technique. A PubMed keyword and MeSH term search was performed, and titles were reviewed for relevance by the first author. Studies related to endovascular repair of iatrogenic injury to the IVC and iliac veins were then read in detail for possible inclusion in the review. Those deemed appropriate were further analyzed for interventional approach, stent type and size, technical success, post-procedural pharmacologic management, complications and surveillance strategy. The initial search resulted in 6221 publications. A total of 17 met criteria for inclusion, all of which were case reports or series. Twenty-six patients were described as suffering iatrogenic injury to the IVC or iliac veins, treated with various types and sizes of stents. All cases achieved technical success with hemorrhage control. Procedural complications occurred in 15.4% of cases, including 3 cases of acute thrombus formation and 1 case of stenosis caudal to the initial stent edge requiring additional stenting. Two additional patients experienced stent occlusion in the surveillance period. Endovascular repair of iatrogenic injury to the IVC and iliac veins can be an effective management option. However, due to limited data regarding this approach, many technical questions remain, including ideal size and type of stent graft, necessity and duration of post-procedural anticoagulant or antiplatelet therapy and appropriate surveillance. Additionally, long term outcomes in this population have not yet been described.

Abstract Number ‐ 34: Basal ganglia infarct volume and risk of hemorrhagic transformation after endovascular thrombectomy

Introduction As more large vessel occlusion stroke patients are treated with endovascular thrombectomy (EVT), understanding the pathophysiology of reperfusion injury and the risks of hemorrhagic transformation (HT) are increasingly important. Pre‐EVT infarct topography may have implications for acute interventional treatments such as stenting, and post thrombectomy care such as antithrombotic choice. We sought to quantify region‐specific volumes of infarcted tissue on pre‐EVT MRI, understand their importance for HT, and identify associations with clinical and imaging characteristics. Methods Patients with pre‐EVT MRI were identified retrospectively from a prospectively maintained database. Each patient’s diffusion weighted sequence underwent manual infarct delineation and was registered to a standard space for overlay with cortical, subcortical, and white matter atlases. Structure‐specific lesion volumes were determined. HT was defined as PH1 or PH2 hemorrhage by ECASS criteria. Variables with p&lt; 0.10 in univariate analyses were included in multivariable models. Logistic regression was performed for associations with hemorrhagic transformation and linear regressions for infarct volumes. Results 165 participants [median age 69 years (interquartile range, IQR 56–79), 56% women] were identified. Risk factors included hypertension (70%), diabetes (20%), atrial fibrillation (34%), and prior stroke/TIA (13%). 52% were treated with intravenous alteplase; 70% achieved TICI 2b‐3 reperfusion. HT occurred in 8%. Pre‐EVT infarct volumes [median (IQR)] were 22 cc (12‐43 cc) for total, 11 cc (6‐19 cc) for white matter, 5 cc (1‐19 cc) for cortex, and 3 cc (1‐6 cc) for basal ganglia. Pre‐EVT infarcts [median (IQR)] were made up of 48% (38‐60%) white matter, 23% (6‐47%) cortex, and 15% (4‐28%) basal ganglia. Paramagnetic sequences showed 3% had petechial hemorrhage and 40% had susceptibility vessel sign. Basal ganglia infarct volume was independently associated with HT (OR = 1.342, 95%CI = 1.002,1.797) in a model including white matter infarct volume, cortex infarct volume, smoking, and puncture‐recanalization time. Basal ganglia infarct volume was linked to susceptibility vessel sign (Beta = 0.233, p = 0.006) and NIHSS (Beta = 0.220, p = 0.012), when controlling for total infarct volume. Conclusions In this cohort, greater basal ganglia infarct volume was associated with a higher risk of hemorrhagic transformation, even when accounting for infarct volume in other regions. Susceptibility vessel sign was associated with basal ganglia infarct volume, which may be related to acute middle cerebral artery thrombus occlusion of perforators. These findings require further study in larger cohorts.

Abstract Number ‐ 170: Trends for Endovascular Mechanical Thrombectomy versus Intravenous Tissue Plasminogen Activator for Vertebrobasilar Stroke Treatment

Introduction Acute vertebrobasilar artery occlusion (VBAO) represents approximately 20% of patients presenting with acute ischemic stroke. The occlusion is caused by an embolus or underlying atherosclerotic disease plaque rupture forming an acute thrombus. Without treatment, VBAO’s mortality nears 80–90%, thus, effective and timely treatment strategies become paramount in managing the patients. Herein, we analyzed the age difference and outcomes in patients that underwent either Endovascular Mechanical Thrombectomy (MT) or intravenous (IV) tissue plasminogen activator (tPA). Methods National Inpatient Sample (NIS) was queried from years 2016 to 2018 using ICD‐10 diagnosis and procedure codes for occlusion or thrombosis of vertebral artery or basilar artery (I63.21, I63.22, I63.01, and I63.02), IV tPA (3E03317), and MT (03CG3ZZ, 03CG3Z6, 03CG3Z7, 03CG4Z6, 03CG4ZZ). Chi‐square test and was used for statistical analysis. Results From 2016 to 2018, there were 37,310 patients admitted with vertebrobasilar stroke. Out of these, IV tPA was administered in 2,530 (6.8%) admissions, whereas MT was done in 2,330 (6.2%) admissions. IV tPA was used significantly more than MT in age groups 65–84 and &gt; = 85 years. MT was used significantly more than IV tPA in age groups 18–44 and 45–64 (Figure 1). There was no significant difference in their use between men and women. In large hospitals, MT was more common than IV tPA (8.1% vs 7%, p &lt; 0.0001), and in small hospitals, IV tPA usage was significantly higher (3.8% vs 2%, p &lt; 0.0001). All‐cause mortality rate was significantly higher in MT than IV tPA admissions (16.8% vs 8.1%, p &lt; 0.0001). There was no significant difference in mean length of stay (LOS) between the two modalities (Figure 1). Conclusions We saw a trend of higher rate of mechcnical thrombectomy in younger age group (18‐64 years) than older, however, no sex difference was noted. All‐cause mortality rate was higher in the mechanical thrombectomy group than intravenous tissue plasminogen activator group. In addition, there was no difference in length of hospital stay.

3D-printed model of simulation for acute thrombus removal in peripheral arteries.

Surgical training and evaluation of medical devices require simulation models. The aim of this study was to assess a 3D-printed model as a training model for peripheral endovascular procedures, including thromboaspiration in acute limb ischemia (ALI). The 3D-simulation model was modeled from an aorta and lower limbs CT scan by segmentation of the arterial light. The 3D simulator was printed in multimaterial with photo-polymerizable resins (Polyjet). The simulator consisted of interchangeable cartridges intended to reproduce the lower limb vasculature. The simulator was connected to a pump to obtain a pulsative flow. A gelled product was positioned in a cartridge just above a stenosis in order to simulate an ALI by in-situ thrombosis. Vascular interventionalists should perform a thrombo-aspiration (Indigo®, Penumbra Inc., Alameda, CA, USA) by crossover in an experimental hybrid room (Discovery®, General Electric, Boston, MA, USA). The analysis of the results was based on the feedback of vascular interventionalists using a Likert Psychometric Scale. A total of 6 vascular surgeons performed two training sessions in real-life conditions. Access to the target lesion was achieved by cross-over or antegrade approach with an 8 F - 45 cm introducer. An angiogram was used to localize the thrombus. Due to the flow, a part of the thrombus was migrating from femoropopliteal segment to below the knee level. Thromboaspiration was realized by Indigo (Penumbra Inc.) CAT-8 and -6 with separators. The average score out of 5 was 4.5 (±0.55) regarding anatomical reproducibility, 4.3 (±0.82) for navigation, and 4.5 (±0.84) for aspiration. The didactical evaluation showed a score of 4.3 (±0.52) for improving technical skills. The improvement of the confidence score in the simulator was +1.2 (±1.72). The 3D-simulation model for peripheral endovascular procedures provides a realistic training for thromboaspiration. This model could mimic different types of peripheral arterial pathologies and participate to the vascular interventionalists training.

Angiopoietin 2 and hsCRP are associated with pulmonary hemodynamics and long-term mortality respectively in CTEPH-Results from a prospective discovery and validation biomarker study.

Chronic thromboembolic pulmonary hypertension (CTEPH) is an underdiagnosed disease of uncertain etiology. Altered endothelial homeostasis, defective angiogenesis and inflammation are implicated. Angiopoietin 2 (Ang2) impairs acute thrombus resolution and is associated with vasculopathy in idiopathic pulmonary arterial hypertension. We assessed circulating proteins associated with these processes in serum from patients with CTEPH (n=71) before and after pulmonary endarterectomy (PEA), chronic thromboembolic pulmonary disease without pulmonary hypertension (CTEPD, n=9) and healthy controls (n=20) using Luminex multiplex arrays. Comparisons between groups were made using multivariable rank regression models. Ang2 and high-sensitivity C-reactive protein (hsCRP) were measured in a larger validation dataset (CTEPH=277, CTEPD=26). Cox proportional hazards models were used to identify markers predictive of survival. In CTEPH patients, Ang2, interleukin (IL) 8, tumor necrosis factor α, and hsCRP were elevated compared to controls, while vascular endothelial growth factor (VEGF) c was lower (p < 0.05). Ang2 fell post-PEA (p < 0.05) and was associated with both pre- and post-PEA pulmonary hemodynamic variables and functional assessments (p < 0.05). In the validation dataset, Ang2 was significantly higher in CTEPH compared to CTEPD. Pre-operative hsCRP was an independent predictor of mortality. We hypothesize that CTEPH patients have significant distal micro-vasculopathy and consequently high circulating Ang2. Patients with CTEPD without pulmonary hypertension have no discernible distal micro-vasculopathy and therefore have low circulating Ang2. This suggests Ang2 may be critical to CTEPH disease pathogenesis (impaired thrombus organization and disease severity).

Efficacy of thrombus aspiration in cardiogenic shock complicating acute myocardial infarction and high thrombus burden

Introduction and objectivesCurrent guidelines do not recommend routine thrombus aspiration in acute myocardial infarction (AMI) because no benefits were observed in previous randomized trials. However, there are limited data in cardiogenic shock (CS) complicating AMI. MethodsWe included 575 patients with AMI complicated by CS. The participants were stratified into the TA and no-TA groups based on use of TA. The primary outcome was a composite of 6-month all-cause death or heart failure rehospitalization. The efficacy of TA was additionally assessed based on thrombus burden (grade I-IV vs V). ResultsNo significant difference was found in in-hospital death (28.9% vs 33.5%; P=.28), or 6-month death, or heart failure rehospitalization (32.4% vs 39.4%; HRadj: 0.80; 95%CI, 0.59-1.09; P=.16) between the TA and no-TA groups. However, in 368 patients with a higher thrombus burden (grade V), the TA group had a significantly lower risk of 6-month all-cause death or heart failure rehospitalization than the no-TA group (33.4% vs 46.3%; HRadj: 0.59; 95%CI, 0.41-0.85; P=.004), with significant interaction between thrombus burden and use of TA for primary outcome (adjusted Pint=.03). ConclusionsRoutine use of TA did not reduce short- and mid-term adverse clinical outcomes in patients with AMI complicated by CS. However, in select patients with a high thrombus burden, the use of TA might be associated with improved clinical outcomes. The study was registered at ClinicalTrials.gov (Identifier: NCT02985008).

Intracardiac Thrombi as a New Variant Cardiovascular Injury in a Previously Healthy COVID-19 Child: Case Report and Follow Up

However, with the onset of the second COVID-19 pandemic wave, single cases of acute thrombotic complications in previously healthy children began to appear. Here we describe the patient with COVID-19 time related acute intracardiac thrombus in a previously healthy 6 year old girl. The treatment according to the national pediatric protocol, included low-molecular weight heparin infusion, high-dose aspirin, methylprednisolone, and intravenous immunoglobulin was lead to dissolving without cardiac surgery. A follow up after 12 months from discharge demonstrated: physical exam, ECG, echocardiography are all normal. Our case presentation shows, that all health care providers must be informed about the full range of complications and even a mild onset of COVID-19 in children.

Abstract 15381: Phlegmasia Cerulea Dolens and Concurrent Gastrointestinal Bleeding: A Dangerous Combination With Challenging Management

Introduction: Phlegmasia cerulea dolens (PCD) is a rare and life-threatening complication related to extensive deep venous thrombosis (DVT) resulting in acute limb ischemia. Treatment options include anticoagulation, thrombolysis and thrombectomy. Case: A 31-year-old female with a history of ulcerative colitis (UC) on chronic steroids presented with acute dyspnea and tachycardia. She was hemodynamically stable. The initial workup included a lower extremity (LE) Doppler ultrasound (US) which showed an acute occlusive thrombus involving the left posterior tibial and popliteal veins, and a computerized tomography angiography (CTA) of her chest which showed bilateral pulmonary emboli. She was placed on heparin drip for 48 hours but due to an episode of acute gastrointestinal (GI) bleeding due to severe UC, anticoagulation was discontinued after an inferior vena cava filter placement and she was discharged from the hospital. After 1 month, she presented with severe diarrhea, hypotension and tachycardia. A chest CTA showed reduced clot burden compared to prior. On hospital day 2, the patient experienced acute onset of severe left LE pain, bluish skin discoloration and rapidly progressing edema. A repeat US showed progression of DVT to the left common femoral vein. The findings were consistent acute limb ischemia in the setting of PCD. She was managed with emergent thrombectomy, with significant amount of thrombus retrieved. Gastroenterology was consulted and GI bleeding did not recur. Discussion: Due to its rarity, there are limited data available to guide PCD management in the setting of elevated bleeding risk such as severe UC. However, after a risk-benefit assessment, we determined that this young patient should be treated with anticoagulation and undergo emergent thrombectomy, which resulted in significant improvement of her symptoms. We highlight the importance of multidisciplinary approach, early diagnosis and prompt treatment in these complex patients.

Abstract 10433: Inhibition of Plasminogen Activator Inhibitor Type 1 in Experimental Venous Thrombosis

Introduction: Conventional treatment of deep vein thrombosis is suboptimal, requiring continuous improvement in knowledge about the disease and a search for new therapeutic approaches. Hypothesis: Blood flow affects the composition of an acute venous thrombus (VT). Aim 1: Compare VT composition under flow and stasis conditions. Aim 2: Evaluate the antithrombotic properties of the novel PAI-1 inhibitor MDI-2268 in-vivo. Methods: C57BL/6 mice, 10-12w, 20-25g were used in electrolytic (EIM) and ligation (LM) models of venous thrombosis. Aim 1: The thrombus weight (TW) and the microstructure of an acute VT (Day 2) in the EIM (n=5) and the LM (n=5) were compared. Expression of PAI-1, tPA, and uPA in the vein wall and plasma levels of D-dimer were investigated. Aim 2: Five EIM groups (n=5) were studied: MDI-2268 1.5 mg/kg (Group 1), MDI-2268 3 mg/kg (Group 2), enoxaparin 7.3 mg/kg (Group 3), MDI-2268 3 mg/kg plus enoxaparin 1.8 mg/kg (Group 4), and DMSO controls (Group 5). TW and bleeding time (BT) on Day 2 were measured. Results: Aim 1: VT within the EIM was smaller compared to the LM (6.2.5±3.6 vs. 26.2±3.6, P&lt;0.05). VT formed within the EIM had a significantly higher amount of plasminogen. The level of D-dimer was 23.4±12.5 and 4.5±1.3 ng/mL/mg in the EIM and LM, respectively (p&lt;0.05). Aim 2: TW was 6.9±3.3 (p&gt;.05), 5.5±1.6 (p=.035), 3.8±1.3 (p=.005), and 4.8±2.4 mg (p=.035) for groups 1,2,3, and 4; compared to 12.7±5.7 mg in the controls. BT was not affected by the MDI-2268. Conclusions: Blood flow pattern significantly affects VT composition. Non-occlusive thrombus has a higher potential to be targeted by the fibrinolytic system due to a higher plasminogen content. MDI-2268 demonstrates strong antithrombotic properties in-vivo and may be associated with a lower risk of bleeding compared to enoxaparin. This data may contribute to a better understanding of the disease process, different outcomes after venous thrombosis, and new therapeutic targets.

Misclassification rate of the angiographically identified culprit lesion in NSTEMI

Abstract Background Correct identification of the culprit lesion in NSTEMI is essential, in particular for patients in whom a culprit-only strategy is attractive (e.g., elderly and frail patients). However, when identifying the culprit lesion in NSTEMI, angiography can be ambiguous and correct culprit identification can therefore be challenging when based on angiography, ECG- and echocardiographic changes alone (standard-of-care). In fact, this challenge remains unresolved and is a continuous limitation in guidelines and in the few clinical trials investigating the revascularization strategy in NSTEMI. Purpose We aimed to investigate the agreement between angiography and cardiac magnetic resonance (CMR) and optical coherence tomography (OCT) in identifying the culprit lesion in non-ST segment elevation myocardial infarction (NSTEMI). Methods In two centres we prospectively enrolled 104 patients. CMR was performed prior to angiography. Operators, blinded to CMR, identified a culprit lesion based on angiography and standard-of-care. OCT was subsequently performed on operator-suspected culprit lesions and stenoses ≥50% diameter. CMR and OCT were reviewed blinded to angiographic culprit identification. Myocardial oedema on CMR was considered the reference standard for a culprit. In the absence of oedema, OCT was used. In case of multiple suspected OCT-lesions, hierarchical criteria for culprit identification were used: acute thrombus &amp;gt; plaque rupture with a cavity &amp;gt; organising thrombus &amp;gt; dissection &amp;gt; calcific nodule. Results The majority of included patients were male (75%) at a mean 63 years of age. Obstructive disease was observed in 85 (82%) patients, of which 53 (51%) had multivessel disease. On a patient-level, angiography identified a culprit lesion in 90 (87%) patients, of which CMR/OCT only identified a culprit in 74 (82%) patients. This constituted a moderate overall positive predictive value of angiography, which was found inferior to CMR/OCT in identifying the culprit lesion. On a lesion-level, CMR/OCT identified a different culprit lesion than angiography in 12 (16%) patients. Of these, only one patient did not receive revascularization of the true culprit lesion. Moreover, in the 14 patients without an angiographic culprit, CMR/OCT identified a culprit in 7 (50%) patients. Thus, angiography including standard-of-care falsely identified the culprit lesion in overall 35 (34%) patients: 7 false negatives, 16 false positive at patient-level, and 12 misclassified angiographic culprits on lesion-level (Figure 1). Specifically, OCT identified 13% misclassified culprit lesions in proximal segments, and provided an added diagnostic value. Conclusions Angiography misclassified the culprit lesion in one in three patients with NSTEMI with respect to both presence and location. OCT complemented angiography in ambiguous cases which underscores the value of OCT in aiding treatment and diagnosis in NSTEMI. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Research Grant at Rigshospitalet, Copenhagen University Hospital, DenmarkNovo Nordisk Foundation, Denmark

Great Safety and Efficacy of a New Drug-eluting-stent manufactured in a developing country at minimal cost: the VSTENT at 3 years follow-up

Abstract Background In the care patients with coronary artery disease, a new drug-eluting stent, the VSTENT, covered with sirolimus was designed and manufactured in a developing country at minimal cost. Beside the clinical concern, from an engineering perspective, the questions were: Was this stent flexible? What was its radial strength? Did this stent brace itself against the wall with a strong strut network? What was the cell size and design? Methods From 6.2019 to 8.2020, 150 patients from 5 hospitals underwent PCI with a new VSTENT in 212 lesions. At the index PCI (D1), a subgroup of 61 patients (40%) was preselected to undergo additional imaging procedures including intravascular ultrasound (IVUS=41) or optical coherence tomography (OCT=20). All patients were followed-up clinically every month for one year. At 6 months (D180) they underwent digital subtraction angiography (DSA=143) or a second IVUS or OCT for the intravascular subgroup. The rate of invasive imaging follow-up was 95% for DSA, 92% for IVUS and 95% for OCT. The rate of major adverse cardiovascular events (MACE: mortality, in-stent restenosis (ISR), Target lesion revascularization (TLR) and data on radial strength, longitudinal flexibility, expansion and coverage were calculated. Results In all patients, the technical success was 100% (successful balloon inflation, complete stent expansion, uneventful balloon removal). The VSTENTs were deployed in arteries of all sizes: small with diameter (D) = 2.5mm in 11.3%, D= 2.75mm in 24.1%, and in large arteries D= or &amp;gt;3mm in 66.6% of patients. The stent length varied from 15–38mm with 80% &amp;gt;20mm. 92% had good apposition as evidenced by OCT or IVUS. There was no acute in-stent thrombus, no loss of side branch and no perforation. There was one cardiac arrest with successful resuscitation. The bench and angiographic data on radial strength, longitudinal flexibility, expansion and coverage were excellent In Figure 1, The VSTENT design has open cells in the middle and closed cell at both distal segments. This design of mixed closed and open cell increases the radial strength at both ends while preventing the diametric difference (dog-boning effect) In Figure 2, after deployment of a VSTENT, the size of the open cell design in the middle of the stent is approximately 3.40 mm2 while the size of the distal closed cells design is 1.7 mm2. At 6 months, the rate of angiographic ISR inside the stent and within the 5 mm from the two ends was 3.5%. The rate of late lumen loss was 0.8mm in the in-stent segment and 0.07mm within 5mm of the two ends. The composite MACE was 4.7% with 1 mortality (0.7%) and 4 TLRs. At 36 months follow-up, only one TLR was reported. Conclusions At 3 years follow-up, the rate of angiographic ISR and TLR of the VSTENT was low. The data on radial strength, longitudinal flexibility, expansion and coverage were excellent. The VSTENT could be an affordable choice for interventional cardiology service in developing countries. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): United Healthcare

Decreased device related thrombus and enhanced neo-endocardial tissue maturation with a new generation left atrial appendage closure (LAAC) device. An anticoagulation and antiplatelet free canin study

Abstract Introduction Device related thrombus (DRT) has been reported in up to 7% of patients post LAAC even while on anticoagulation. Clinical predictors of DRT are poorly understood and may be related to patient, procedural and device factors. A next generation WATCHMAN LAAC device (NG) is identical in shape and geometry to the current WATCHMAN FLX device (CW) but has a device coating designed to make it hemocompatible and less thrombogenic. Objective To evaluate the incidence and burden of WM surface thrombus formation as detected longitudinally by TEE and at necropsy in a canine model implanted with the NG device. Methods The study included 12 canine (6 implanted with CW and 6 implanted with NG) that underwent serial TEE follow up at 14, 28 and 45 days to evaluate surface thrombus on WM face. This was a challenged canine model designed to induce thrombus with no anticoagulation or antiplatelet use throughout the study. D-dimer levels were measured at 7 days and 45 days and compared to baseline measurements. Results All devices were successfully implanted. TEE follow up at 14 days showed noticeably reduced thrombus burden on the NG device compared to CW (fig.1) with even further diminution by 28 days in the NG (6/6) as compared to only in 1/6 in the CW group (fig.2). After 45 days in-life, the post-fixation trim en-face images show a smooth, glistening neoendocardial covering (absence of acute thrombus material) in all (6/6) NG compared to only 2/6 in the CW (fig.3). The CW had 3/6 devices with exuberant, bulging calcified thrombus mass one of which was considered to be a mobile DRT. D Dimer levels at 7 and 45 days were significantly lower relative to baseline in the NG compared to CW. Conclusion The NG device compared to the CW device was associated with markedly less thrombus formation at 14 days and no thrombus formation at 28 days post implant on no anticoagulant and no antiplatelet therapy along with a more mature uniform tissue coverage at 45 days. The WATCHMAN FLX Pro device coating is a promising step to reduce DRT even without the use of anticoagulation and antiplatelets and merits further investigation in human studies. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Boston Scientific

Percutaneous Left Atrial Appendage Closure With a Novel LAA Occluder for Stroke Prevention in Atrial Fibrillation.

More than 90% of thromboses originate from the left atrial appendage (LAA) in patients with nonvalvular atrial fibrillation (NVAF). This study was designed to investigate the safety and efficacy of LAA closure with the Leftear device (Pulse Scientific) in NVAF patients. A prospective, multicenter, registry-based study was conducted in 200 NVAF patients with CHA2DS2-VASc (congestive heart failure, hypertension, age, diabetes, previous stroke/transient ischemic attack, vascular disease, female sex) scores≥2. The primary safety endpoint was defined as any serious adverse events. Efficacy was assessed by a primary composite endpoint of hemorrhagic or ischemic stroke, systemic embolism, and cardiac or unexplained death at 1 year of follow-up. The device was implanted in 196 patients, with 1-stop LAA closure combined with atrial fibrillation ablation implemented in 133 patients. The immediate success rate was 100%. There were serious adverse events in 9 patients (4.5%; 95%CI: 1.6%-7.4%), which mainly occurred in 1-stop LAA closure. All pericardial tamponades occurred in 6patientswith 1-stop LAA closure. No patient experienced a major bleeding event or acute device-related thrombus. During the 12-month follow-up period, the risk of the primary composite endpoint was 1.6% (95%CI: 0.3%-4.5%), and statistical noninferiority was achieved (the upper bound of 95%CI: 4.5%< the prespecified maximum annual incidence of 8.0%). Ischemic stroke occurred in 1 patient, 3 patients had incomplete LAA sealing, and no delayed device-related thrombus was found. LAA closure with the novel disc-like occluder shows high procedural success, satisfactory safety, andencouraging efficacy for stroke prevention in patients with NVAF. Compared with 1-stop LAA closure, single LAAclosure may be more tolerable. (A multicenter, single-arm clinical trial to evaluate the efficacy and safety of left atrial appendage system for left atrial appendage occlusion in patients with non-valvular atrial fibrillation; ChiCTR1900023035).

Plasma D-dimer levels are correlated with disease severity among hypertensive patients: A comparative cross-sectional study.

It has been reported that inappropriate acute thrombus formation is the pathophysiological substrate underlying increased risk and severity of target organ damage in hypertension (HTN). However, the relationship between severity of HTN and D-dimer has not been well characterized. The study was aimed to assess plasma D-dimer level and its correlation with disease severity among hypertensives. A comparative cross-sectional study was conducted at Wuhan Asia Heart Hospital among 100 participants (60 hypertensives and 40 controls). The correlation between variables were determined using correlation coefficients, regression analysis, and also using different parametric and nonparametric tests. We observed higher D-dimer levels among hypertensives compared to the healthy controls (P < .001). The D-dimer levels were found to be increased significantly with the severity of HTN (P < .001). D-dimer was found to have a diagnostic power of 86.9% in differentiating complicated from uncomplicated HTN at 0.83 mg/L cutoff value. This study suggests that D-dimer level was higher among hypertensives than control groups and it was also increasing significantly with the severity of HTN. This suggests that hypercoagulability of fibrin plays a role in the occurrence of thromboembolic complications of hypertensive patients.

Age and composition of the thrombus retrieved by mechanical thrombectomy from patients with acute ischemic stroke are associated with revascularization and clinical outcomes

IntroductionUnderstanding the composition of stroke thrombi retrieved by mechanical thrombectomy is essential to clarify the pathogenesis of stroke. However, it is difficult to evaluate thrombus composition precisely and objectively. Immunohistochemical staining was used to evaluate thrombus composition and age. Materials and methodsConsecutive thrombi (n = 108) retrieved from patients who underwent mechanical thrombectomy for acute large-vessel ischemic stroke were retrospectively analyzed. Lytic features of granulocytes and CD163 were estimated as indicators of the age of the cardioembolic (CE) thrombus. ResultsThe stroke subtypes were as follows: CE, 74 cases; large artery atherosclerosis, 11; undetermined etiology, 12; and other determined etiology, 11. There were no statistical differences in thrombi composition according to stroke subtypes. The fibrin area was positively correlated with the red blood cell (RBC) and platelet areas. The following analysis was performed using CE only. Regarding age, the thrombus was judged as fresh in 30.0 % and older in 70.0 % based on the lytic features. The RBC areas of older thrombi were smaller than those of fresh thrombi. The puncture-to-reperfusion time of older thrombi was longer than that of fresh thrombi. Platelet-rich thrombi were associated with a greater number of maneuvers, a smaller prevalence of TICI 3, and unfavorable functional outcomes compared to platelet-poor thrombi. The number of CD163 positive cells in thrombi with anticoagulants was higher than in those without anticoagulants. ConclusionThrombus composition correlated with revascularization and clinical outcomes. The composition of an acute ischemic thrombus may reflect the pathophysiology of stroke and influence treatment efficacy.