Persistent and Recurrent Device-Related Thrombus After Left Atrial Appendage Closure: Incidence, Predictors, and Outcomes.

BACKGROUND: Scarce data exist on the evolution of device-related thrombus (DRT) after left atrial appendage closure (LAAC). OBJECTIVES: This study sought to assess the incidence, predictors, and clinical impact of persistent and recurrent DRT in LAAC recipients. METHODS: Data were obtained from an international multicenter registry including 237 patients diagnosed with DRT after LAAC. Of these, 214 patients with a subsequent imaging examination after the initial diagnosis of DRT were included. Unfavorable evolution of DRT was defined as either persisting or recurrent DRT. RESULTS: DRT resolved in 153 (71.5%) cases and persisted in 61 (28.5%) cases. Larger DRT size (OR per 1-mm increase: 1.08; 95% CI: 1.02-1.15; P = 0.009) and female (OR: 2.44; 95% CI: 1.12-5.26; P = 0.02) were independently associated with persistent DRT. After DRT resolution, 82 (53.6%) of 153 patients had repeated device imaging, with 14 (17.1%) cases diagnosed with recurrent DRT. Overall, 75 (35.0%) patients had unfavorable evolution of DRT, and the sole predictor was average thrombus size at initial diagnosis (OR per 1-mm increase: 1.09; 95% CI: 1.03-1.16; P = 0.003), with an optimal cutoff size of 7 mm (OR: 2.51; 95% CI: 1.39-4.52; P = 0.002). Unfavorable evolution of DRT was associated with a higher rate of thromboembolic events compared with resolved DRT (26.7% vs 15.1%; HR: 2.13; 95% CI: 1.15-3.94; P = 0.02). CONCLUSIONS: About one-third of DRT events had an unfavorable evolution (either persisting or recurring), with a larger initial thrombus size (particularly >7 mm) portending an increased risk. Unfavorable evolution of DRT was associated with a 2-fold higher risk of thromboembolic events compared with resolved DRT.

Antemortem diagnosis of external iliac arterial thromboembolism in a calf using contrast-enhanced computed tomography: a case report.

A 28-day-old Holstein calf with astasia (i.e., right hind limb flaccid paralysis) was referred to Large Animal Veterinary Educational Center. Thoracic radiographs showed an alveolar pattern and air bronchograms indicating pneumonia, whereas skeletal radiography showed muscle atrophy of the right hind limb but no abnormalities in the coxofemoral and stifle joints. Contrast-enhanced computed tomography revealed the pulmonary abscess in the right cranial pulmonary lobe and a thrombus (5 × 5 × 20 mm) in the right external iliac artery distal to the bifurcation of the abdominal aorta. These findings were confirmed via pathological examination. Streptococcus bovis/equinus complex colonies were isolated from the thrombus and pulmonary abscess. Thus, the pulmonary abscess was considered the infectious source of the thromboembolism in the right external iliac artery. Arterial thromboembolism should be included in the differential diagnoses in calves with astasia but without radiographic skeletal abnormalities.

[Right Brachial Artery Thromboembolism After Left Upper Lobectomy].

A 71-year-old man underwent a computed tomography( CT) scan to check for prostate cancer metastasis. It revealed a lung tumor in the left upper lobe, and he was referred to our division. Under clinical diagnosis of primary lung cancer, left upper lobectomy was performed. Dense adhesion due to the history of tuberculosis was observed. On the first postoperative day, he complained of sudden numbness in his right arm during rehabilitation. The emergent contrast-enhanced CT revealed the right brachial arterial thromboembolism. We performed an embolectomy, and further analysis of the postoperative enhanced CT revealed a longer left upper pulmonary vein stump than usual. We thought it to be the cause of the thrombus formation and started anticoagulation therapy. The postoperative course was uneventful, without recurrence of thromboembolism.

Invasive Pulmonary Angiogram Performance and Interpretation in the Diagnosis of Pulmonary Thromboembolic Disease.

Invasive or selective pulmonary angiography has historically been used as the gold standard diagnostic test for the evaluation of a wide array of pulmonary arterial conditions, most commonly pulmonary thromboembolic diseases. With the emergence of various noninvasive imaging modalities, the role of invasive pulmonary angiography is shifting to the assistance of advanced pharmacomechanical therapies for such conditions. Components of invasive pulmonary angiography methodology include optimal patient positioning, vascular access, catheter selections, angiographic positioning, contrast settings, and recognition of angiographic patterns of common thromboembolic and nonthromboembolic conditions. We review the pulmonary vascular anatomy, step-by-step performance, and interpretation of invasive pulmonary angiography.

Impact of size ratio on thromboembolic events based on diffusion-weighted imaging after coil embolization for unruptured basilar apex aneurysm.

PURPOSE: Coil embolization is one of the main endovascular treatment for basilar apex aneurysms (BAAs), and thromboembolic events are important complications of coil embolization. Even in small aneurysms, there is a risk of rupture, and aggressive treatment should be considered for unruptured BAAs. Using diffusion-weighted imaging (DWI), the study aimed to investigate thromboembolic events after coil embolization for unruptured BAAs by focusing on the absolute aneurysm size and relative aneurysm size (size ratio [SR]). METHODS: To evaluate the predictors of thromboembolic events, patients were divided into those with and without hyperintensity on DWI after coil embolization. Patient and radiographic characteristics were compared between the two groups. SR was defined as the maximum aneurysm diameter divided by the average parent artery diameter. RESULTS: Fifty-six unruptured BAAs in 56 patients were investigated. The mean aneurysm size and SR were 7.61 ± 2.18 mm and 2.74 ± 1.45, respectively. Postprocedural hyperintensity on DWI was detected in 17 patients (30.4%). SR was significantly larger in the group with hyperintensity on DWI (3.75 ± 1.97 vs. 2.3 ± 0.82, P < 0.01) in the univariate analysis. Multivariate analysis revealed that SR> 3.0 was a significant predictor of thromboembolic events after coil embolization for unruptured BAAs (odds ratio: 12.15; 95% confidence interval: 2.95-49.98; P < 0.01). CONCLUSIONS: This study showed that SR is a predictor of thromboembolic events after coil embolization for unruptured BAAs. Therefore, if even in small BAAs, if the BAAs dome height is large compared to the diameter of the posterior cerebral artery (e.g., there is a large SR), preoperative evaluation of the use of antiplatelet therapy is important, particularly to prevent thromboembolic events.

The Combination of Vacuum-Assisted Thromboaspiration and Covered Stent Graft for Acute Limb Ischemia due to Thromboembolic Complications of Popliteal Aneurysm.

BACKGROUND: We present a standardized protocol of endovascular revascularization for patients with acute limb ischemia due to popliteal artery aneurysm (PAA) thromboembolic complication, based on the combination of vacuum-assisted thromboaspiration to improve tibiopedal outflow and covered stent graft to exclude the PAA. METHODS: All patients with a diagnosis of PAA complicated by thromboembolic events undergoing total endovascular rescue were prospectively enrolled in a dedicated database from November 2018 to November 2021. To assess vessel patency, the TIPI (Thromboaspiration In Peripheral Ischemia) classification was used. The primary end point was the primary technical success (at least one tibial vessel with a TIPI flow of 2 or 3). The 30-day overall mortality and amputation rates were considered as secondary end points. Patients' overall survival, limb salvage, freedom from reocclusion and reinterventions were reported as secondary late outcomes using Kaplan-Meier method. RESULTS: Seventeen male patients were enrolled with a mean age of 75.7 ± 9 years. Rutherford grading score was IIa in 52.9% (9/17) and IIb in 47.1% (8/17). PAA mean diameter was 37.4 ± 11.2 mm. All patients had tibial arteries involvement, and in 9 cases (52.9%) there was also the occlusion of the PAA. Mechanical thrombectomy with Indigo/Penumbra thromboaspiration system was used in all patients. PAAs were excluded using one or more VIABAHN covered endografts (range 1-3 pieces). Technical success was achieved in 94.1%. Fasciotomy was performed in 1 case (5.9%). Mortality and amputation rates at 30-day follow-up were respectively 0% and 5.9%. Survival rates at 6, 12, and 24 months were respectively 94.1%, 86.3%, and 67.9%. Secondary patency was achieved in all cases (100%). Freedom from reintervention was 80.4%, 65.8%, and 54.8% at 6-, 12-, and 24-month follow-up. Limb salvage was 88.2% at 6-, 12-, and 24-month follow-up, respectively. CONCLUSIONS: Although preliminary, our experience of total endovascular rescue for complicated PAA with thromboembolic events highlighted promising rates of limb salvage at 30 days after intervention. The total endovascular approach seems able to maximize tibiopedal outflow offering an interesting strategy in limb salvage.

Ultrasonographic findings of feline aortic thromboembolism.

OBJECTIVES: The aim of the study was to describe the ultrasonographic characteristics of feline aortic thromboembolism (ATE) and determine potential associations between ultrasonographic findings and prognosis. METHODS: Data were retrospectively collected from the medical records (2013-2021) of cats that were diagnosed ultrasonographically with ATE based on the presence of a thromboembolus (TE) in the distal aorta beginning after the departure of the renal arteries. RESULTS: Twenty-nine cats were included in this study. The most frequent location for an ATE was at the aortic trifurcation. The median length of TEs was 9 mm (range 3.5-42.9). TEs appeared homogeneous and isoechoic to surrounding tissues in all cases. No correlation was found between the appearance of the TE and the duration of clinical signs. The obstruction of blood flow in the distal aorta at the aortic trifurcation was complete in 66% of cases and incomplete in 34% of cases. The survival rate was significantly lower when the obstruction was complete (11%, 95% confidence interval [CI] 2-34) compared with incomplete (70%, 95% CI 35-92). The arterial wall characteristics were as follows: smooth and thin (62%), and hyperechoic (38%). CONCLUSIONS AND RELEVANCE: Increased vascular obstruction of TEs was associated with a lower survival rate.

Association of left ventricular abnormalities with incident cerebrovascular events and sources of thromboembolism in patients with chronic Chagas cardiomyopathy.

BACKGROUND: Although Chagas cardiomyopathy is related to thromboembolic stroke, data on risk factors for cerebrovascular events in Chagas disease is limited. Thus, we assessed the relationship between left ventricular (LV) impairment and cerebrovascular events and sources of thromboembolism in patients with Chagas cardiomyopathy. METHODS: This retrospective cohort included patients with chronic Chagas cardiomyopathy who underwent cardiovascular magnetic resonance (CMR). CMR was performed with a 1.5 T scanner to provide LV volumes, mass, ejection fraction (LVEF), and myocardial fibrosis. The primary outcome was a composite of incident ischemic cerebrovascular events (stroke or transient ischemic attack-TIA) and potential thromboembolic sources (atrial fibrillation (AF), atrial flutter, or intracavitary thrombus) during the follow-up. RESULTS: A total of 113 patients were included. Median age was 56 years (IQR: 45-67), and 58 (51%) were women. The median LVEF was 53% (IQR: 41-62). LV aneurysms and LV fibrosis were present in 38 (34%) and 76 (67%) individuals, respectively. The median follow-up time was 6.9 years, with 29 events: 11 cerebrovascular events, 16 had AF or atrial flutter, and two had LV apical thrombosis. In the multivariable model, only lower LVEF remained significantly associated with the outcomes (HR: 0.96, 95% CI: 0.93-0.99). Patients with reduced LVEF lower than 40% had a much higher risk of cerebrovascular events and thromboembolic sources (HR: 3.16 95% CI: 1.38-7.25) than those with normal LVEF. The combined incidence rate of the combined events in chronic Chagas cardiomyopathy patients with reduced LVEF was 13.9 new cases per 100 persons-year. CONCLUSIONS: LV systolic dysfunction is an independent predictor of adverse cerebrovascular events and potential sources of thromboembolism in patients with chronic Chagas cardiomyopathy.

Thromboembolic Events Detected by Diffusion-Weighted Magnetic Resonance Imaging after Flow Diverter Treatment: The Impact of Procedure Time.

BACKGROUND: Periprocedural thromboembolism is a serious complication of endovascular treatment for intracranial aneurysms. In addition to symptomatic ischemia, asymptomatic postprocedural diffusion-weighted image-positive lesions (DPLs) are considered important. However, few studies have reported significant risk factors associated with DPLs and symptomatic ischemic stroke after flow diverter (FD) treatment. This study aimed to investigate the frequency and risk factors associated with DPLs after FD treatment. METHODS: Between November 2015 and December 2021, 84 patients harboring 85 untreated, unruptured intracranial aneurysms treated with FD were enrolled. RESULTS: DPLs after FD treatment were confirmed in 74 patients (87.1%), among whom 69 (93.2%) were clinically asymptomatic. In the univariate analyses, age >55 years (P = 0.040), smoking (P = 0.023), preprocedural P2Y12 reaction unit value of >185 (P = 0.030), larger dome size of >9.3 mm (P = 0.013), and prolonged procedure time >80 minutes (P < 0.001) were significantly associated with postprocedural DPLs. In the multiple logistic regression model, only prolonged procedure time >80 minutes (odds ratio, 10.72; 95% confidence interval, 1.346-233.899; P = 0.023) was statistically significant. The mediator effect showed that the association between procedure time and the occurrence of DPLs was not significantly modified by any other factors, although only adjunctive coiling showed a tendency (P-value for interaction = 0.070). CONCLUSIONS: Prolonged procedure time >80 minutes was the only identifiable factor related to postprocedural DPLs. Adjunctive coiling tended to mediate the effects of a prolonged procedure time on the occurrence of DPLs after FD treatment.

Usefulness of maximum intensity projection images of non-enhanced CT for detection of hyperdense middle cerebral artery sign in acute thromboembolic ischemic stroke.

PURPOSE: To compare the sensitivity of the hyperdense middle cerebral artery (MCA) sign between maximum intensity projection (MIP) and conventional averaged images in patients with acute focal neurological deficits with acute thromboembolic MCA occlusion (MCA occlusion group) and patients with acute focal neurological deficits without MCA occlusion (control group). MATERIALS AND METHODS: Initial computed tomography (CT) scans on admission were reconstructed with 5 mm thickness at every 3 mm interval for averaged and MIP images from 1 mm thickness non-contrast axial source images. Images were obtained from 30 cases each in the MCA occlusion and control groups. The CT values in the region of interests (ROIs) on the affected and unaffected sides of the MCA were compared. To compare CT values among subjects, the CT values were normalized by obtaining a ratio on the affected and unaffected sides, and the normalized CT values were analyzed using the receiver operating characteristic (ROC) curve. RESULTS: The hyperdense MCA sign was visually detected on MIP images in 90% cases and on 5 mm averaged images in only 57% cases in the MCA occlusion group. Based on the ROC analysis of the normalized ratio on the affected and unaffected sides, area under the curve of MIP image and averaged image was 0.941 and 0.655, respectively. On MIP images, the optimal threshold of the ratio on the affected and unaffected sides was 1.152 (sensitivity: 90.0%, and specificity: 93.3%). CONCLUSION: The hyperdense MCA sign sensitivity on 5 mm MIP images was significantly higher than that on conventional 5 mm averaged CT images. This could be useful for the early initiation of proper therapy for patients with acute focal neurological deficits.

Edoxaban Versus Dual Antiplatelet Therapy for Leaflet Thrombosis and Cerebral Thromboembolism After TAVR: The ADAPT-TAVR Randomized Clinical Trial.

BACKGROUND: It is unknown whether the direct oral anticoagulant edoxaban can reduce leaflet thrombosis and the accompanying cerebral thromboembolic risk after transcatheter aortic valve replacement. In addition, the causal relationship of subclinical leaflet thrombosis with cerebral thromboembolism and neurological or neurocognitive dysfunction remains unclear. METHODS: We conducted a multicenter, open-label randomized trial comparing edoxaban with dual antiplatelet therapy (aspirin plus clopidogrel) in patients who had undergone successful transcatheter aortic valve replacement and did not have an indication for anticoagulation. The primary end point was an incidence of leaflet thrombosis on 4-dimensional computed tomography at 6 months. Key secondary end points were the number and volume of new cerebral lesions on brain magnetic resonance imaging and the serial changes of neurological and neurocognitive function between 6 months and immediately after transcatheter aortic valve replacement. RESULTS: A total of 229 patients were included in the final intention-to-treat population. There was a trend toward a lower incidence of leaflet thrombosis in the edoxaban group compared with the dual antiplatelet therapy group (9.8% versus 18.4%; absolute difference, -8.5% [95% CI, -17.8% to 0.8%]; P=0.076). The percentage of patients with new cerebral lesions on brain magnetic resonance imaging (edoxaban versus dual antiplatelet therapy, 25.0% versus 20.2%; difference, 4.8%; 95% CI, -6.4% to 16.0%) and median total new lesion number and volume were not different between the 2 groups. In addition, the percentages of patients with worsening of neurological and neurocognitive function were not different between the groups. The incidence of any or major bleeding events was not different between the 2 groups. We found no significant association between the presence or extent of leaflet thrombosis with new cerebral lesions and a change of neurological or neurocognitive function. CONCLUSIONS: In patients without an indication for long-term anticoagulation after successful transcatheter aortic valve replacement, the incidence of leaflet thrombosis was numerically lower with edoxaban than with dual antiplatelet therapy, but this was not statistically significant. The effects on new cerebral thromboembolism and neurological or neurocognitive function were also not different between the 2 groups. Because the study was underpowered, the results should be considered hypothesis generating, highlighting the need for further research. REGISTRATION: URL: https://www. CLINICALTRIALS: gov. Unique identifier: NCT03284827.

A Clot-Homing Near-Infrared Probe for In Vivo Imaging of Murine Thromboembolic Models.

Direct thrombus imaging contributes to early detection of thrombosis, and animal models with clinical relevance are vital in the development of new thrombolytics. Here, a facile clot-homing strategy is developed based on the finding that blood clot is negatively charged. Positively charged pentalysine moiety is coupled with phthalocyanine-based fluorophore , and its applications in murine thromboembolic models are described. The probe efficiently stains the cryosection of intracranial thrombi retrieved from patients with cardioembolic stroke. In vitro, the fibrin-rich clot is labeled by the probe at sub-nanomolar concentration. The probe-labeled clot is formed into microparticles (1-5 µm) and intravenously injected into mice for pulmonary embolism modeling. In vivo imaging demonstrates fast accumulation and retention of fluorescent clot microparticles in pulmonary vessels. Recombinant tissue-type plasminogen activator (rtPA) administration greatly reduces near-infrared signal in the lungs in a time-dependent manner. This probe is also tested in a stroke model. Middle cerebral artery is occluded by autologous thrombi formed under electric stimulation. In vivo imaging shows that the probe efficiently homes to thrombus at early stage. Hence, this probe has great potential in real-time imaging of thromboembolism in clinically relevant models, promoting bench-to-bedside translation. This clot-homing principle can be used in other applications.

Effect of Antiplatelet Preparation Before Endovascular Thrombectomy for Cerebral Infarction on Procedural Thromboembolism.

AIM: To compare an antiplatelet-preparation group with a no-preparation group to evaluate the effect of the antiplatelet preparation on procedural thromboembolism during endovascular thrombectomy (EVT) with diffusion-weighted imaging (DWI), retrospectively. MATERIAL AND METHODS: From January 2017 to April 2020, EVT was performed in 60 patients with cerebral infarction. Patients were categorized into the antiplatelet-preparation group (n=25) or the no-preparation group (n=35). Procedural thromboembolism was defined as new DWI-positive lesions in other areas of the occluded artery after EVT. RESULTS: The antiplatelet-preparation and no-preparation groups did not differ in the rate of procedural thromboembolism occurrence (6/25 [24.0%] vs. 6/35 [17.1%]; p=0.532). Procedural thromboembolism was associated with age (74.4 ± 6.95 years vs. 65.7 ± 12.9 years; p=0.028), atherosclerotic occlusion (66.7% vs. 29.2%; p=0.022), and procedural time (97.4 ± 45.7 min vs. 60.1 ± 28.8 min; p=0.001). Multivariable logistic regression analysis showed that factors affecting procedural thromboembolism during EVT for cerebral infarction were old age (odds ratio [OR], 1.133; 95% confidence interval [CI], 1.009-1.273; p=0.035), atherosclerotic occlusion (OR, 7.434; 95% CI, 1.272-43.431; p=0.026), and longer procedural time (OR, 1.023; 95% CI, 1.001 - 1.046; p=0.006). CONCLUSION: The antiplatelet preparation had no significant protective effect on procedural thromboembolism during EVT for cerebral infarction. Old age, atherosclerotic occlusion, and longer procedural time were independent risk factors for procedural thromboembolism during EVT for cerebral infarction.

Presentation, Diagnosis and Management of Innominate Artery Thromboembolism.

PURPOSE: Acute thromboembolic disease of the innominate artery (IA) poses a unique set of therapeutic challenges, owing to its contribution to both the cerebral and upper extremity circulation, and risks of distal embolization via the carotid and subclavian arteries, respectively. Herein, we present a 74-year-old female who presents with acute IA thrombus treated successfully with right axillary and common carotid exposure and aspiration catheter-directed mechanical thrombectomy (CDT). Furthermore, an emerging use of CDT and its application in acute thromboembolism are outlined. CASE REPORT: A 74-year-old female with history of right lung transplant for pulmonary fibrosis with severe pulmonary hypertension, and stage IIIA left lung adenocarcinoma status post left lower lobectomy undergoing adjuvant chemotherapy presented with acute IA thrombus and right-sided stroke. She was treated successfully with right axillary and common carotid exposure and aspiration CDT. Computed tomography angiography performed 1 month postoperatively confirmed patent IA with no evidence of residual or recurrent thrombus. CONCLUSION: There are currently no standard guidelines on the management of acute IA thromboembolism, with mostly individual cases reported in the literature describing this rare entity. Nevertheless, this unique clinical entity mandates expeditious diagnostic and therapeutic approaches in order to avoid permanent neurologic deficits from distal embolization. Our case demonstrates that aspiration CDT may be an effective treatment modality for patients with acute IA thrombus.

Percutaneous Aspiration Thrombectomy for Arterial Thromboembolic Occlusion Following Percutaneous Transluminal Angioplasty: Technical Success Rates and Clinical Outcomes.

PURPOSE: We aimed to analyze the technical success rate of manual percutaneous aspiration thrombectomy (PAT) in patients with peripheral arterial thromboembolism as a complication of infrainguinal percutaneous transluminal angioplasty (PTA) and we sought to evaluate the 30-day postintervention clinical outcome. MATERIALS AND METHODS: We retrospectively identified 29 patients (men/women, 18/11; mean age, 74 years) who underwent infrainguinal PAT to treat thromboembolic complications of infrainguinal PTA. Primary and secondary technical successes were defined as residual stenosis of < 50 % of the vessel diameter after PAT alone and PAT with additional PTA, respectively. Clinical outcome parameters (e. g., amputation, need for further intervention) were evaluated during the first 30 days after intervention. RESULTS: The primary and secondary technical success rates were 58.6 % (17/29) and 79.3 % (23/29), respectively. Clinical outcome data were available for 93.1 % (27/29) of patients. No further intervention was required within 30 days in 81.5 % (22/27) of patients. Four patients underwent minor amputations owing to preexisting ulcerations (Rutherford Category 5), and no patients underwent major amputations (Rutherford Category 6). Revascularization of the previously treated vessel segment with PTA was necessary on the first postintervention day in one patient. CONCLUSION: Manual PAT, with PTA if needed, has a good technical success rate and satisfactory early clinical outcome in patients with iatrogenic thromboembolic complications after infrainguinal PTA. KEY POINTS: · Manual PAT is a possible first-choice treatment of infrainguinal PTA-induced acute thromboembolism.. · Performing additional PTA increases the success rate of manual PAT.. · Unlike catheter-directed intraarterial lysis, manual PAT carries no risk of bleeding.. CITATION FORMAT: · Schicho A, Bäumler W, Verloh N et al. Percutaneous Aspiration Thrombectomy for Arterial Thromboembolic Occlusion Following Percutaneous Transluminal Angioplasty: Technical Success Rates and Clinical Outcomes. Fortschr Röntgenstr 2022; 194: 291 - 295.

Balloon-Assisted Endovascular Thrombectomy for Tibial Thromboembolism.

We present a novel approach to endovascular thrombectomy using the Penumbra Indigo® Aspiration System with balloon assistance for a thromboembolic occlusion to the tibioperoneal trunk and tibial arteries causing acute limb ischemia. This technique allows for effective suction thrombectomy of distal vessels into a shorter, large-diameter aspiration catheter, thereby overcoming the limitations of the longer but smaller aspiration catheters.