Fresh Thrombus Research Articles

Localization of Hemostasis Elements in Aspirated Coronary Thrombi at Different Stages of Evolution.

The structure of aspirated coronary thrombus in ST-segment elevation myocardial infarction (STEMI) is still being studied. Our aims were to characterize coronary thrombi of different ages, focusing on the appearance of activated protein C (APC/PC) and its relation to the elements of neutrophil extracellular traps (NETs), and the factors closely related to fibrin as factor XIII (FXIII) and α2 plasmin inhibitor (α2-PI). The thrombi of n = 24 male patients with atherosclerotic coronary plaque rupture related to native coronary artery occlusion were selected for histopathology analysis. Thrombus age was distinguished as fresh, lytic, and organized, and then analyzed by immunofluorescent staining and confocal microscopy. FXIII was present at a high level and showed a high degree of co-localization with fibrin in all stages of thrombus evolution. The amount of α2-PI was low in the fresh thrombi, which increased significantly to the lytic phase. It was evenly distributed and consistently associated with fibrin. APC/PC appeared in the fresh thrombus and remained constant during its evolution. The presence of NET marker and CD66b was most dominant in the lytic phase. APC/PC co-localization with the elements of NET formation shows its role in NET degradation. These observations suggest the importance of searching for further targeted therapeutic strategies in STEMI patients.

Rupture of the ascending aorta 6 months after TAVI procedure caused by TAVI prosthesis

BackgroundTranscatheter aortic valve implantation (TAVI) is indicated for elderly patients who often have severe comorbidities and high operative risk. Despite many advantages, it carries the potential for both early and late complications. The literature reports mainly periprocedural problems. This case report describes a rare instance of ascending aortic rupture as a late complication following TAVI.Case presentationAn 81-year-old male with severe aortic stenosis (AS) was a non-surgical patient due to a high operative risk (EuroSCORE II 14.08%) and comorbidities, including cardiovascular problems, chronic obstructive pulmonary disease, myelodysplastic syndrome. During the TAVI procedure Medtronic CoreValve™ Evolut™ R-26 was implanted via the right femoral artery. Postoperative period elapsed without complications and the patient was discharged home. Six months later, the patient was re-admitted to the hospital on an emergency basis and transferred directly to the operating room due to ascending aortic rupture (EuroSCORE II 53.20%, GERAADA score 64.9%). Computed tomography angiography (CTA) showed aortic rupture with a multiple fresh blood reservoirs and thrombus around the ascending aorta originating from the spot where the nitinol frame of the TAVI valve was attached to the native aorta. Supracoronary excision of the ascending aorta with implantation of a vascular graft (Intergard Woven Graft 34 mm) was performed, preserving the earlier implanted TAVI valve. On the 9th day after surgery the patient’s general condition deteriorated, he suffered from circulatory and respiratory insufficiency. Furthermore, a gastrointestinal bleeding with the need for gastro-, and colonoscopy and multiple blood transfusions occurred. Patient developed urosepsis and acute renal failure with the need for hemodiafiltration. Despite intensive treatment, further deterioration of the medical condition of the patient. and finally the multiple organ failure was observed. Patient died on the 50th postoperative day.ConclusionsTAVI is a safe method of treating severe AS, especially recommended for non-surgical candidates. Rupture of the ascending aorta is a rare but serious complication of TAVI that usually occur during or shortly after the procedure. This case report highlights the importance of post-procedural monitoring for such TAVI complications, even in the late period following TAVI, and if such complications occur, taking the risk to perform a life-saving operation.

Predominance of M2 macrophages in organized thrombi in chronic thromboembolic pulmonary hypertension patients.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a debilitating disease characterized by thrombotic occlusion of pulmonary arteries and vasculopathy, leading to increased pulmonary vascular resistance and progressive right-sided heart failure. Thrombotic lesions in CTEPH contain CD68+ macrophages, and increasing evidence supports their role in disease pathogenesis. Macrophages are classically divided into pro-inflammatory M1 macrophages and anti-inflammatory M2 macrophages, which are involved in wound healing and tissue repair. Currently, the phenotype of macrophages and their localization within thrombotic lesions of CTEPH are largely unknown. In our study, we subclassified thrombotic lesions of CTEPH patients into developing fresh thrombi (FT) and organized thrombi (OT), based on the degree of fibrosis and remodeling. We used multiplex immunofluorescence histology to identify immune cell infiltrates in thrombotic lesions of CPTEH patients. Utilizing software-assisted cell detection and quantification, increased proportions of macrophages were observed in immune cell infiltrates of OT lesions, compared with FT. Strikingly, the proportions with a CD206+INOS- M2 phenotype were significantly higher in OT than in FT, which mainly contained unpolarized macrophages. Taken together, we observed a shift from unpolarized macrophages in FT toward an expanded population of M2 macrophages in OT, indicating a dynamic role of macrophages during CTEPH pathogenesis.

Strategy to optimize PeriproCeduraL AnticOagulation in structural transseptal interventions: Design and rationale of the STOP CLOT trial

Both transcatheter edge-to-edge repair (TEER) of mitral regurgitation or left atrial appendage closure (LAAC) require periprocedural anticoagulation with unfractionated heparin (UFH) that is administered either before or immediately after transseptal puncture (TSP). The optimal timing of UFH administration (before or after TSP) is unknown. The Strategy To Optimize PeriproCeduraL AnticOagulation in Structural Transseptal Interventions trial (STOP CLOT Trial) was designed to determine if early anticoagulation is effective in reducing ischemic complications without increasing the risk of periprocedural bleeding.The STOP CLOT trial is a multicenter, prospective, double-blind, placebo-controlled, randomized trial. A total of 410 patients scheduled for TEER or LAAC will be randomized 1:1 either early UFH administration (iv. bolus of 100Units/kg UFH or placebo, given after obtaining femoral vein access and at least 5 minutes prior to the start of the TSP) or late UFH administration (iv. bolus of 100Units/kg UFH or placebo given immediately after TSP). Prespecified preliminary statistical analysis will be performed after complete follow-up of the first 196 randomized subjects. To ensure blinding, a study nurse responsible for randomization and UFH/placebo preparation is not involved in the care of the patients enrolled into the study. The primary study endpoint is a composite of (1) major adverse cardiac and cerebrovascular events (death, stroke, TIA, myocardial infarction, or peripheral embolization) within 30 days post-procedure, (2) intraprocedural fresh thrombus formation in the right or left atrium as assessed with periprocedural transesophageal echocardiography, or (3) occurrence of new ischemic lesions (diameter ≥4 mm) on brain magnetic resonance imaging performed 2-5 days after the procedure. The safety endpoint is the occurrence of moderate or severe bleeding complications during the index hospitalization. Protocols of periprocedural anticoagulation administration during structural interventions have never been tested in a randomized clinical trial. The Stop Clot trial may help reach consensus on the optimal timing of initiation of periprocedural anticoagulation.

Abstract TMP87: Thrombus Age in Ischemic Stroke With Atrial Fibrillation

Background and purpose: Because the biochemical composition of thrombus changes after formation over time, thrombus maturation in the left atrium may affect clot compositions in ischemic stroke with atrial fibrillation (AF). We aimed to investigate the association of the age of retrieved thrombi with clinical features and outcomes after MT for ischemic stroke with AF. Methods: We retrospectively reviewed consecutive patients with ischemic stroke with known AF or AF diagnosed after stroke onset who underwent MT and whose retrieved thrombi were pathologically analyzed. Thrombi were classified as fresh (<1 day) and older (1-5 days) based on the areas (≤20 % or >20 %) of lytic features of granulocytes in the section. Components of thrombi were quantified using immunostaining. Outcomes included first pass effect (FPE, extended Thrombolysis in Cerebral Infarction [eTICI] 2c/3 after first pass) and favorable outcome (3-month modified Rankin Scale score of 0 to 2 or equal to premorbid mRS score). Results: Of 168 patients, 62 patients (37%) had older thrombi. The presence of older thrombi was independently associated with the higher CHADS 2 score (adjusted OR [aOR], 1.46; 95% confidence interval [CI], 1.07-1.99). Older thrombi had the higher proportion of fibrin, platelets, von Willebrand factor, and neutrophil extracellular traps than fresh thrombi. FPE was less frequently achieved in patients with older thrombi than those with fresh thrombi (21% versus 43%; aOR, 0.36; 95% CI, 0.17-0.77). Favorable outcomes were fewer in patients with older thrombi than those with fresh thrombi (40% versus 73%; aOR, 0.37; 95% CI, 0.16-0.85). Conclusions: In patients with ischemic stroke with AF, older thrombi was associated with cardiovascular risk factors and included abundant amounts of components associated with the thrombectomy resistance. Patients with older thrombi had poorer functional outcomes presumably due to concomitant risk factors and worse revascularization outcomes.

Histological Features of In-Stent Restenosis after Iliac Vein Thrombus Removal and Stent Placement in a Goat Model

PurposeTo establish an animal model for in-stent restenosis (ISR) after postthrombotic iliac vein stent placement and characterize histopathological changes in tissue within the stented vein. Materials and MethodsIliac vein thrombosis was induced using balloon occlusion and thrombin injection in 8 male Boer goats. Mechanical thrombectomy and iliac vein stent placement were performed 3 days after thrombosis induction. Restenosis was evaluated by venography and optical coherence tomography (OCT) at 1 and 8 weeks after stent placement, and stent specimens were taken for pathological examination after the animals were euthanized. ResultsThrombosis induction was successful in all 8 goats, with >80% iliac vein occlusion. After thrombus removal, OCT revealed considerable venous intimal thickening and a small number of mural thrombi. Neointimal hyperplasia with thrombus formation was observed in all goats 1 week after stent implantation; the degree of ISR was 15%–33%. At 8 weeks, the degree of ISR was 21%–32% in 3 goats, and stent occlusion was observed in 1 goat. At 1 week, the neointima predominantly consisted of fresh thrombi. At 8 weeks, proliferplastic fibrotic tissue and smooth muscle cells (SMCs) were predominant, and the stent surfaces were endothelialized in 2 of 3 goats and partially endothelialized in 1 goat. ConclusionsIn the goat model, postthrombotic neointimal hyperplasia in the venous stent may result from time-dependent thrombus formation and organization, accompanied by migration and proliferation of SMCs, causing ISR. These results provide a basis to further explore the mechanism of venous ISR and promote the development of venous stents that reduce neointimal hyperplasia.

Adhesion of vessel wall to stentriever during combined technique for mechanical thrombectomy in acute ischemic stroke: A histomorphological study.

Detection of vessel wall tissue in thrombus material in patients with ischemic stroke is judged as vascular injury. So far, several studies investigated components of the free clots after mechanical thrombectomy. The aim of this retrospective study was to investigate the involvement and role of the stentriever in vessel wall injury by analysis of the composition of adherent tissue to the stentriever during combined aspiration thrombectomy with stentriever. Stentriever with adherent tissue and free clots in aspiration samples from patients undergoing mechanical thrombectomy (aspiration plus stentriever) were separately assessed for the occurrence of parts of vascular tissue together with clinical and interventional data as well as clinical outcome data. Specimens were analyzed histomorphologically and immunohistochemically. Findings, focused on parts of vessel wall were reported together with clinical data. Specimens from 21 identified patients were available. Parts of the vessel wall were detected in 7 out 21 (33%) samples. All specimens revealed fresh thrombus material without signs of organization or atheromatous tissue. In 90% of patients mTICI was greater than 2b without signs of secondary vessel injury. No vascular tissue was found in free clots of the aspiration samples. The examination of adherent tissue to the stentriever instead of the examination of free clots may affect the number of detected parts of vessel wall. Further studies in combination with vessel wall imaging may elucidate the origin of remnants of vessel wall.

Acute lower extremity arterial thrombosis associated with nephrotic syndrome in adults: case series and literature review

BackgroundNephrotic syndrome (NS) is a condition associated with hypercoagulability. Thromboembolic events are a well-recognized complication of NS. Venous thrombosis is well known, while arterial thrombosis, which is more severe, occurs less frequently and is mainly reported in children in the literature. The aim of this study was to understand these rare adult cases of NS associated with acute lower extremity arterial thrombosis and draw attention to them to prevent misdiagnosis and delayed treatment.MethodsFrom January 2011 and October 2022, we conducted a retrospective study of patients with NS and arterial thrombosis. Their clinical manifestations, imaging characteristics, treatments and outcomes were analyzed and compared, and a literature review was performed.ResultsNine adults with NS and acute lower limb arterial thrombosis were described. In seven of these patients, six had fresh thrombi that preceded the NS diagnosis, while one had a history of NS for 14 years and previously underwent an emergency thrombectomy. Three of the seven patients eventually underwent above-knee amputations, and the other four underwent arterial revascularization with satisfactory recovery of lower-extremity perfusion. In addition to the seven patients mentioned above, the other two received successful anticoagulant treatment, as the thrombosis was present only in the popliteal artery.ConclusionAcute lower extremity arterial thrombosis is a rare but serious and potentially lethal complication in patients with NS, and early recognition and appropriate management are crucial for good patient outcomes.

Ischemic stroke in a young adult with a known epileptogenic arteriovenous malformation: illustrative case.

Brain arteriovenous malformations (AVMs) usually manifest as hemorrhages or seizures. They rarely present with ischemic symptoms, especially in young patients. We present a case of an epileptogenic AVM that led to cerebral infarction due to paradoxical embolic occlusion of the middle cerebral artery (MCA) involving the main feeder of the lesion. A 35-year-old male had been suffering from AVM-associated epilepsy for 10 years and was scheduled for surgery. He suddenly developed right-sided hemiconvulsions followed by hemiparalysis and impaired consciousness. Computed tomography revealed no intracerebral hemorrhage, and symptoms were initially thought to indicate epilepsy and Todd's palsy. Because of his prolonged symptoms, he underwent magnetic resonance imaging, which revealed a large cerebral infarction due to occlusion of the MCA involving the main feeder of the AVM. The patient underwent AVM resection, and the partially thrombosed nidus was completely removed. Histopathological investigation revealed a fresh thrombus in totally occluded nonarteriosclerotic feeders. He had no atrial fibrillation; however, subsequent transesophageal echocardiography revealed a patent foramen ovale, suggesting a paradoxical embolism. This case serves as a reminder that AVMs can present with considerable variability. Acute cerebral infarction should be considered a possible mechanism of seizures, even in patients with epileptogenic AVM.

Venous Screening Activities at the Site of Hokkaido East Iburi Earthquake: Report from the Result of Venous Screening in Preventive Awareness Activities.

After previous earthquakes, high prevalence of cardiovascular diseases including venous thromboembolism (VTE) has been reported. We performed venous screening at the site of Hokkaido East Iburi Earthquake which happened at 6th September 2018. VTE screening using ultrasound sonography was performed for total 7 days at Atsuma town, Mukawa town and Abira town (total 9 shelters). Deep vein thrombosis (DVT) was found in 19 of 195 evacuees (9.7%), including 8 fresh thrombus cases (4.1%). On multivariable analysis of evacuees and shelter environment factors, systolic blood pressure, use of cardboard bed and toilet environment were significant predictor of DVT. Introduction and setting-up of cardboard beds were found as an important shelter environment factor. (This is secondary publication from Jpn J Phlebol 2021; 32(1): 5-10.).

A targeted activatable NIR-II nanoprobe for positive visualization of anastomotic thrombosis and sensitive identification of fresh fibrinolytic thrombus

Anastomotic thrombosis prevalently causes anastomosis failure, accompanied with ischemia and necrosis, the early diagnosis of which is restricted by inherent shortcomings of traditional imaging techniques in clinic and lack of appropriate prodromal biomarkers for thrombosis initiation. Herein, a fresh thrombus-specific molecular event, protein disulfide isomerase (PDI) is innovatively chosen as the activating factor, and a thrombosis targeting and PDI-responsive turn-on near infrared II (NIR-II) fluorescence nanoprobe is firstly developed. The supramolecular complex-based nanoprobe IR806-PDA@BSA-CREKA is fabricated by assembling NIR-II emitting cyanine derivative IR806-PDA with bovine serum albumin (BSA), which could ameliorate the stability and pharmacokinetics of the nanoprobe, addressing the contradiction in the balance of brightness and biocompatibility. The NIR-II-off nanoprobe exhibits robust turn-on NIR-II fluorescence upon PDI-specific activation, in vitro and in vivo. Of note, the constructed nanoprobe demonstrates superior photophysical stability, efficient fibrin targeting peptide-derived thrombosis binding and a maximum signal-to-background ratio (SBR) of 9.30 for anastomotic thrombosis in NIR-II fluorescent imaging. In conclusion, the exploited strategy enables positive visualized diagnosis for anastomotic thrombosis and dynamic monitoring for thrombolysis of fresh fibrinolytic thrombus, potentially contributes a novel strategy for guiding the therapeutic selection between thrombolysis and thrombectomy for thrombosis treatment in clinic.

A novel coronary artery healing pattern suggesting the axial progression of coronary plaques.

A 54-year-old man, current smoker, without previous cardiovascular history was admitted for an inferior transient ST-segment elevation myocardial infarction. An emergent coronary angiogram revealed an unstable, non-obstructive, thrombus-rich plaque in the mid segment of the right coronary artery (RCA) (Panel A). Optical coherence tomography (OCT) imaging disclosed a healthy vessel wall in the proximal RCA, along with a long, heterogenous plaque at the culprit lesion, where three distinct phenotypes were clearly recognized (Panels a-d, circle denotes wire artifact). First, the very proximal segment of the plaque showed a layered morphology with multiple high and low signal-rich strata, suggestive of an old healing process (Panels a and b, arrowheads). In the middle part of the plaque, a superficial, laden, organized circumferential thrombus was observed, probably reflecting an early healing stage (Panel c, asterisks). Finally, the most distal part of the lesion showed a plaque rupture with a large, ‘red’ fibrin-rich, fresh protruding thrombus (Panel d, star). Percutaneous coronary intervention with a new-generation stent obtained excellent results.

Acidente vascular cerebral isquêmico secundário a Carotid Web: Relato de Caso

Background: The carotid web is a rare type of myofibrous dysplasia which is receiving increased attention for being a risk factor of ischemic stroke. It is a rare carotid artery disease, and its incidence is about 0,62%. The carotid web presents as a membrane located inside the arterial lumen, protruding from the posterior wall of the carotid sinus or the starting portion of the internal carotid artery. In some cases, thrombus can be seen on the carotid web. This occurs due to blood stasis and platelet activation, resulting in thrombosis which can embolize intracranially. Case presentation: 40 years-old female presents with transient left paresthesia and paresis, lasting 60 minutes. Weeks after, she presented a stronger and transient event, associated with dysarthria and rhyme deviation. Magnetic resonance investigation showed ischemic stroke in the middle cerebral artery area and thrombus in the right internal carotid artery, and angiography evidenced the presence of a probable atherosclerotic plaque in the right carotid sinus, attached to a fresh thrombus. She started anticoagulation therapy. In control exam, the arterial area in the right carotid sinus was identified without the presence of thrombus, allowing a better characterization of a membrane attached to the posterior wall of the internal carotid artery, coming up with features compatible with carotid web. Due to the recurrence of neurological deficits, besides being transitory, it was opted for endovascular treatment, aiming to avoid the evolution of a transient neurological deficit to a permanent one. She was submitted to angioplasty and maintained on double antiagregation due to stent and, until the moment, did not present any new neurovascular events. Conclusion: The relevancy of this report is due to carotid web being an under-recognized cause of cryptogenic stroke that should always be suspected when there is recurrent infarction in the territory of one internal carotid artery.

Cardiac rupture during acute myocardial infarction : Autopsy study (2004–2020)

IntroductionCardiac rupture is a rare but critical complication of myocardial infarction with an incidence of 1 to 3% of cases. We aimed in this autopsy study to analyze the anatomical, epidemiological, cardiac, and coronary profiles of cardiac rupture in the Monastir region. MethodsWe conducted a descriptive study with retrospective data collection of all cases of myocardial infarction complicated by a cardiac rupture over seventeen years (2004–2020). ResultsThirty-one cases were included in this study. The mean age of the cases was 67 years with a male predominance. Sixteen cases (57%) had cardiovascular risk factors. The most common symptomatology reported before death was acute chest pain in 57% of cases. Fourteen cases (45%) corresponded to the definition of sudden cardiac death. At autopsy, the heart had a mean weight of 452.78 grams. A large hemopericardium was associated in 90% of cases. Myocardial rupture involved the posterior wall of the left ventricle in 50% of cases. The myocardial rupture occurred at a site of acute myocardial infarction in 86% of cases and on a myocardial scar in 14% of cases. The coronary study showed double or triple vessel atherosclerotic coronary artery disease in 57% of cases with fresh thrombi at the infarct-related coronary in 11% of cases. ConclusionsOur analysis found that cardiac rupture mostly involved elderly subjects with underlying cardiovascular risk factors. Our findings sustain that age is a determining prognostic factor after acute coronary syndrome with the need for further education and awareness-raising efforts to speed up access to care for these patients.

Staged endovascular recanalization for symptomatic atherosclerotic non-acutely occluded internal carotid artery

Symptomatic "non-acutely" occluded internal carotid artery (NAOICA) results in stroke, cognitive impairment, and hemicerebral atrophy through cerebral hypoperfusion and artery-to-artery embolism. Atherosclerosis is the main cause of NAOICA. Conventional one-stage endovascular recanalization showed effectiveness but was plagued by many challenges. This retrospective analysis reports the technical feasibility and outcomes of the staged endovascular recanalization in patients with NAOICA. Eight consecutive patients with atherosclerotic NAOICA and ipsilateral ischemic stroke within 3 months between January 2019 and March 2022 were retrospectively reviewed. The patients (all males, with a mean age of 64.6 years) underwent staged endovascular recanalization 13 to 56 days after documented occlusion by imaging techniques (mean 28.8 days); the mean follow-up period was 20 months (range: 6-28). The approach of the staged intervention was as follows. In the first stage, the occluded ICA was successfully recanalized using the simple small balloon dilation technique. In the second stage, angioplasty with a stent implant was performed with >50% residual stenosis in the initial segment or ≥70% residual stenosis in the C2-C5 segment. The technical success rate, the incidence of clinical adverse events (any stroke, death, cerebral hyperperfusion), and long-term in-stent stenosis (ISR) and reocclusion rates were evaluated. Technical success was achieved in seven patients, with early reocclusion occurring in one patient after the first-stage intervention. There were no adverse events observed within 30 days (0%), and long-term reocclusion and long-term ISR rates were both 14% (1/7). However, all patients developed iatrogenic arterial dissections during the first stage, indicating the challenge of reaching the true lumen through the occlusion site without damaging the intima. Based on the National Heart, Lung and Blood Institute (NHLBI) classification, there were two type A, four type B, three type C, and two type D dissections. The mean time interval between the two stages was 46.1 days (21-152 days). All type A and B dissections resolved spontaneously after ≥3 weeks of dual antiplatelet therapy, whereas most type C and all type D dissections did not heal spontaneously before the second stage. Also, one type C dissection led to reocclusion. This observation suggested that occlusions without flow limit and persistent vessel staining or extravasation could be clinically observed, while severe dissections (characterized as type C or greater) required prompt stenting rather than conservative treatment. Performing high-resolution MRI preoperatively to exclude fresh thrombus in the occluded vessel segment is indispensable in selecting appropriate candidates for endovascular recanalization. This could avoid downstream embolism during the interventional procedure. This retrospective study found that staged endovascular recanalization for symptomatic atherosclerotic NAOICA may be feasible with an acceptable technical success rate and a low complication rate in the selected candidates.

Prosthetic heart valve thrombosis - a headache for the heart team: A case report

Introduction. Prosthetic valve thrombosis is usually a subacute or chronic condition, although it may also present with a fresh thrombus. It occurs in two forms: obstructive and non-obstructive thrombosis. Case Report. We present a case of a female patient who underwent mitral valve replacement with mechanical prosthesis due to severe mitral stenosis. The postoperative course was uneventful and the patient was discharged on vitamin K antagonist therapy with international normalized ratio target 3.0. Five months later, the patient was admitted with severe shortness of breath and signs of acute heart failure. International normalized ratio at that moment was 2.3. Transthoracic echocardiography indicated severely raised gradient across the prosthetic valve and mechanical valve malfunction was suspected. Cinefluoroscopy showed that one of the prosthetic valve leaflets was completely immobile. Transesophageal echocardiography definitely confirmed thrombosis of the prosthetic valve with large multiple thrombi that completely fixed one leaflet in closed position, and partially limited the motion amplitude of the other leaflet. There were thrombi floating between the left ventricle and left atrium. Thrombectomy of the prosthetic valve was performed, which was sufficient for the complete restoration of the mechanical valve function. The vitamin K antagonist dosage was carefully up-titrated in order to reach and maintain the target international normalized ratio of 3.0. Conclusion. Prosthetic valve thrombosis is a serious and life-threatening condition that requires urgent management. Coordination and cooperation of the whole heart team is necessary for optimal choice of treatment, which primarily includes surgery or fibrinolysis.

Abstract 15294: Right Atrial Thrombus Extraction Through Angiovac - A Challenge Based on Chronicity

Case Presentation: 23-year-old woman with right ovarian dysgerminoma, treated with debulking surgery and bleomycin, etoposide, and platinum, found to have a right atrial (RA) mass on post-chemotherapy surveillance CT and referred to the cardiology clinic. Her vitals were stable, lungs were clear to auscultation, RRR without murmurs, no JVD or LE edema. On labs, hgb:11g/dL and LDH:283 units/L(135 to 214 units/L). A transthoracic echocardiogram (TTE) and a cardiac MRI revealed a mass of RA at the junction of inferior vena cava (IVC) entry into RA, measuring 3x1.3 cm in the 2-chamber view and 2.4x1.8 cm in the 4-chamber view (Fig A,B) with prolapse into the right ventricle (RV) in diastole. Based on cardiac MRI’s short and long inversion time imaging characteristics, thrombus was the most likely diagnosis (Fig C). Shared decision-making with the patient included options: 1) open heart surgery for removal; 2) interventional aspiration thrombectomy; or 3) conservative treatment with anticoagulation (AC). After six weeks of AC with enoxaparin, TTE revealed a RA thrombus of the same size as previously (2.8x1.2 cm). Given the lack of improvement, she agreed to an invasive procedure to remove the mass using an AngioVac aspiration system (AngioDynamics, Latham, NY). The AngioVac cannula maneuvered in the RA under fluoroscopic and TEE guidance to capture the RA mass. However, the mass broke into two pieces, one piece still attached to the RA and the other piece lodged in the AngioVac cannula (Fig D,E). She remained hemodynamically stable after the procedure. The pathology of the RA mass revealed an organized thrombus (Fig F). She had no complaints on follow-up in the clinic and continued on AC for 6 months. Discussion: Percutaneous aspiration thrombectomy using the AngioVac system has become a novel option for removing commonly encountered intravascular material, such as fresh thrombi or emboli in the RA, RV, SVA, IVC, and the iliofemoral vein, but may be complicated in old thrombi.

Abstract 13016: Tumor or Thrombus?: Intracardiac Thrombus Masquerading as a Tumor

Introduction: Intracardiac masses comprise thrombi, vegetations, and tumors. Multimodality imaging modalities are often relied upon for a definitive diagnosis. We present a case of a left ventricular (LV) thrombus with characteristic of on contrast echocardiography that thrombus based on cardiac MRI. The mass resolved with anticoagulation. Case: A 56-year-old male with non-ischemic cardiomyopathy was admitted for management of decompensated heart failure. Transthoracic echocardiography (TTE) showed reduced left ventricular ejection fraction of 20 to 25% with diffuse hypokinesis. There was a newly detected large intracardiac mass seen in the left ventricle (figures 1-3) that enhanced with echocardiographic contrast (figure 2). Delay enhancement imaging on cardiac MRI, however, revealed a hypodense mass suggestive of a thrombus (figure 3). The patient started anticoagulation. An echocardiogram performed a month later revealed complete resolution of mass, confirming the thrombotic nature of mass (figure). Discussion: Contrast enhancement echocardiography is very helpful for characterization of intra-cardiac masses. Tumors usually enhance with contrast while thrombi are generally dark. Our case is unusual, the cardiac mass hyper-enhanced with echocardiographic contrast but had thrombus-like characteristics on cardiac MRI. The mass was proven to be a thrombus over time since it resolved with anticoagulation. Echocardiographic contrast usually fails to penetrate hard, chronic thrombi. However loosely structured, fresh thrombi may allow some passage of contrast. This has been demonstrated in carefully conducted in-vitro studies showing that imaging characteristics of newly formed thrombus is often bright with echocardiographic contrast. This underscores the importance of multi-modality imaging to diagnose the nature of a cardiac mass.

Abstract 10017: Which Thrombi at the Apex of the Left Ventricle Were More Prone for Embolization and Stroke?

Introduction: Patients with apical thrombus due to anterior wall ST segment Elevation Myocardial Infarction (AWMI) or dilated cardiomyopathy (DilCM) have high risk of emboli, including stroke. Hypothesis: Which factor of a thrombus at the apex of the left ventricle makes it vulnerable for or resistant to embolization? Is it its loose (or well organized) tissue formation as a fresh (or old) thrombus so it disintegrates quickly (or stays resistant) and becomes vulnerable for (or less prone to) embolization? Methods: Patients with AWMI or DilCM with apical thrombus by echo were consecutively enrolled. Patients with atrial fibrillation were excluded. The data to be collected included: (1) Time of discovery of apical thrombi by echo to time of stroke (2) result of treatment (thrombolysis with long term vit K antagonists vs novel oral anticoagulants (NOACs) and (3) pattern of recovery. Results: From 2010-2021, there were 32 patients identified with apical thrombus. 12 patients due to AWMI and 20 patients due to Dil CM. 3 AWMI patients developed stroke (25%) within a mean of 7.5 days after discovery while only 2 patients with Dil CM had stroke (10%) 21 days after discovery (p<0.05). At the time of stroke, all apical thrombi of AWMI patients were small, of round shape, protruding out and of heterogenous consistency (mixed black and white intensity on echo). The patients responded well to thrombolysis and recovered near completely. While for patients with Dil CM, all apical thrombi were moderately large, of flat surface incorporating into the contour of the apex, non-protruding and of homogenous consistency. When these patients had stroke, the size of stroke was large and more resistant to thrombolysis. Their recovery was slow with a lot of deficits. Conclusions: For apical thrombi from AWMI, the thrombi were fresh so they disintegrated quickly and could cause more stroke however because of their smaller size and loose consistency, the recovery was more complete. The apical thrombi from Dil CM were more organized so they dissolved more slowly, caused less stroke however they were more resistant to thrombolysis. Their recovery was more limited. Larger database needs to confirm the above findings and their clinical implications.

High incidence of pulmonary artery thrombosis after balloon pulmonary angioplasty in CTEPH patients receiving direct oral anticoagulants

Abstract Background Chronic thromboembolic pulmonary hypertension (CTEPH) requires life-long anticoagulant therapy, whereas limited data exist on the safety and efficacy of direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) along with balloon pulmonary angioplasty (BPA). Objectives To evaluate outcomes and complications in CTEPH following BPA for individuals receiving DOACs or VKAs. Methods Consecutive CTEPH patients underwent BPA from September 2014 to August 2021 were included in a retrospective analysis. Complications during BPA, post-BPA hemodynamics and bleeding events were obtained from patient's medical records. Our routine follow-up “selective” pulmonary angiography, to evaluate all segmental pulmonary arteries one by one at six months and every year after final BPA session, was performed to elucidate the incidence of in-situ fresh floating thrombus. Results Of total 250 individuals, 104 were treated with DOACs and 146 with VKAs following BPA. Mean observation period was 905 (SD ± 660) days. Total 1278 BPA sessions were performed among the period in which 409 sessions were treated with DOACs and 869 sessions with VKAs. Significant improvements in hemodynamics and functional status were observed in both groups following BPA. There was no significant difference of hemoptysis during BPA between DOACs and VKAs (7.1% vs 10.1%, P=0.131). Major bleeding events during observation period were equivalent in those treated with DOACs and VKAs. No significant re-elevation of pulmonary artery pressure was observed in both groups after BPA. Follow-up selective pulmonary angiography identified in-situ fresh floating thrombus in pulmonary artery in 22 cases of total 769 follow-up sessions. The occurrence of fresh thrombus was significantly higher in those receiving DOACs than VKAs in therapeutic range of PT-INR >1.8 (3.9% vs 1.2%, P=0.023) whereas no significant difference between DOACs and overall VKAs (3.9% vs 2.4%, P=0.177) Conclusions Post-BPA hemodynamic outcomes and bleeding events appear unaffected by choice of anticoagulant. However, the incidence of in-situ pulmonary thrombosis detected by selective pulmonary angiography was significantly higher in those receiving DOACs than VKAs in therapeutic range, suggesting inadequate anticoagulation under current dose of DOACs. Our study provides a rationale for further examination to evaluate the efficacy of DOACs in CTEPH. Funding Acknowledgement Type of funding sources: None.