Recanalization of a chronic occlusion flow-diverter device in a patient with a paraclinoid giant aneurysm recurrence. Clinical observation.

Paraclinoid internal carotid artery (ICA) aneurysms are associated with a high mortality rate, which gradually increases without intervention. Surgical clipping or coiling of large aneurysms with inadequate neck and adductor artery expansion will not guarantee a successful outcome. Carotid surgical trapping or endovascular occlusion of the adductor artery can help to isolate the aneurysm from circulation, but it comes at the expense of sacrificing a major blood vessel responsible for significant cerebral perfusion. Currently, a technique has been developed to redirect blood flow and stimulate gradual thrombosis in the aneurysm cavity to reduce pressure on its walls. However, in cases of recurrent aneurysm and stent thrombosis in these patients, it is necessary to consider destructive surgery. The 65-year-old patient, who had a history of migraine, was diagnosed with a large aneurysm. He was initially treated with the Pipeline Flex stent from Medtronic, but after 5 months, he experienced 2 transient ischemic attacks. Subsequent CT scans revealed no signs of brain damage, but a brain CTA revealed the recurrence of an internal carotid artery paraclinoid aneurysm with the occlusion of the pipeline device and contrast flowing parallel to the aneurysm wall. This case is an example of successful recanalization of an occluded flow diverter device in a patient with recurrent internal carotid aneurysm.

Treating Chronic Iliac Vein Stent Occlusion in an Office-Based Lab Setting.

Iliac vein stenting is performed when sufficient venous patency is not achieved via angioplasty or lysis. Iliac vein stenting is known to be effective; however, occlusion of the stent occurs occasionally. There is a lack of effective treatment options for those with failed prior venous stents, and traditional methods may involve the removal of the stent and surgical reconstruction. We present a patient with a right leg post-thrombotic syndrome and narcotic abuse after occlusion of a previously placed right common iliac/external iliac vein stent 25 years prior. After transfer to an office-based lab (OBL), femoral vein access was achieved. Then, a second stent was deployed adjacent to the previously chronically thrombosed stent. Imaging confirmed adequate deployment of the new stent and venous flow. Treatment resulted in a significant decrease in patient pain and cessation of narcotics. We demonstrate successful recanalization of a right iliac vein thrombosis via parallel deployment of a stent adjacent to a chronically thrombosed stent.

Imaging of Deep Venous Pathology.

Imaging plays an important role in the identification and assessment of clinically suspected venous pathology. The purpose of this article is to review the spectrum of image-based diagnostic tools used in the investigation of suspected deep vein disease, both obstructive (deep vein thrombosis and post-thrombotic vein changes) as well as insufficiency (e.g., compression syndromes and pelvic venous insufficiency). Additionally, specific imaging modalities are used for the treatment and during clinical follow-up. The use of duplex ultrasound, magnetic resonance venography, computed tomography venography and intravascular ultrasound as well as conventional venography will be discussed in this pictorial review.

Diagnostic accuracy of 3-item stroke scale for detection of cerebral large vessel occlusion: A systematic review and meta-analysis.

BACKGROUND: Prompt identification of large vessel occlusion (LVO) in acute ischemic stroke (AIS) is crucial for expedited endovascular therapy (EVT) and improved patient outcomes. Prehospital stroke scales, such as the 3-Item Stroke Scale (3I-SS), could be beneficial in detecting LVO in suspected patients. This meta-analysis evaluates the diagnostic accuracy of 3I-SS for LVO detection in AIS. METHODS: A systematic search was conducted in Medline, Embase, Scopus, and Web of Science databases until February 2024 with no time and language restrictions. Prehospital and in-hospital studies reporting diagnostic accuracy were included. Review articles, studies without reported 3I-SS cut-offs, and studies lacking the required data were excluded. Pooled effect sizes, including area under the curve (AUC), sensitivity, specificity, diagnostic odds ratio (DOR), positive and negative likelihood ratios (PLR and NLR) with 95% confidence intervals (CI) were calculated. RESULTS: Twenty-two studies were included in the present meta-analysis. A 3I-SS score of 2 or higher demonstrated sensitivity of 76% (95% CI: 52%-90%) and specificity of 74% (95% CI: 57%-86%) as the optimal cut-off, with an AUC of 0.81 (95% CI: 0.78-0.84). DOR, PLR, and NLR, were 9 (95% CI: 5-15), 2.9 (95% CI: 2.0-4.3) and 0.32 (95% CI: 0.17-0.61), respectively. Sensitivity analysis confirmed the analyses' robustness in suspected to stroke patients, anterior circulation LVO, assessment by paramedics, and pre-hospital settings. Meta-regression analyses pinpointed LVO definition (anterior circulation, posterior circulation) and patient setting (suspected stroke, confirmed stroke) as potential sources of heterogeneity. CONCLUSION: 3I-SS demonstrates good diagnostic accuracy in identifying LVO stroke and may be valuable in the prompt identification of patients for direct transfer to comprehensive stroke centers.

An Institutional Perspective on the Number of Stent Retriever Pass and Rate of Recanalization in Mechanical Thrombectomy for Acute Ischemic Stroke: When to Stop?

Background and purpose: Mechanical thrombectomy is the standard treatment modality for flow restoration in acute ischemic stroke. In cases of persistent occlusion, the optimal number of retrieval attempts before considering procedure termination is currently undetermined and is a topic for research. Therefore in this study, we studied the impact of the number of stent retrieval maneuvers on the recanalization of vessels. Methods: In this retrospective single-center observational study we included 52 patients with large vessel occlusion who underwent stent retriever mechanical thrombectomy. Successful recanalization rate was defined as modified TICI (Thrombolysis in Cerebral Infarction) 2b or 3. Result: The overall successful recanalization rate was 44.24%. The recanalization rate per stent retrieval attempt was the highest in 1st attempt (28.84%) and no recanalization was observed with the 3rd, 5th, and 6th attempts (p<0.001). At most 6 retrieval attempts were used. Conclusions: After two retrieval attempts, 91% of the patients were successfully recanalized and other after the 5th attempt could not result in recanalization.

Mechanical Thrombectomy in Medium Vessels Occlusion (MeVOs): An Institutional Experience with M2 Divisions of Middle Cerebral Artery.

Background: Mechanical thrombectomy has been established as a safe, standard and effective treatment option for occlusions of the proximal segment of the middle cerebral artery (MCA), as demonstrated in numerous studies. However, performing thrombectomy in the M2 divisions of MCA presents inherent challenges. In this institutional experience, we aim to delineate the recanalisation rates achieved through mechanical thrombectomy in cases involving the M2 segment of the MCA. Methods: We conducted a retrospective analysis of patients who underwent thrombectomy due to M2 MCA occlusions in the period from January 2018 to December 2021. Various factors affecting recanalisation rates were assessed. Results: A total of 15 patients with M2 segment occlusions of the middle cerebral artery were included in the study, comprising 11 in the superior division and 4 in the inferior division. The successful recanalisation rate was 72.33%, with notably higher success observed in cases of inferior division occlusion. The primary outcome of our study was the mTICI recanalisation status, categorised as successful recanalisation (mTICI = 2b or mTICI = 3) and unsuccessful recanalisation (mTICI = 1 or mTICI = 2a) and mRS at 6 months. None of the predictors assessed reached statistical significance. Conclusions: Mechanical thrombectomy demonstrates favourable efficacy and recanalisation rates in cases of M2 MCA division occlusion. Notably, inferior division occlusions exhibit a higher likelihood of successful recanalisation.

Selective Angiographic Evaluation in Patients with Simple-Type Pulmonary Arteriovenous Malformations Treated with Vascular Plug.

PURPOSE: To evaluate the angiographic recanalization rate of patients who underwent embolization juxta-proximal to the sac with AMPLATZER Vascular Plug type IV (AVP IV) for a simple pulmonary arteriovenous malformation (PAVM). MATERIAL AND METHODS: Ten patients (7 females and 3 males; median age, 47 years [range 28-83 years]) with 19 simple-type PAVMs who underwent embolization using an AVP IV between May 2015 and November 2021 were included in this retrospective study. The median feeding artery diameter on computed tomography was 4.0 mm (range 3-5.9 mm), and the median ratio of AVP IV size to feeding artery diameter on computed tomography was 1.5 (range 1.3-2.1). Technical success was defined by AVP IV placement at the junction between the pulmonary artery and the sac, or the pulmonary artery within 1 cm from the junction and beyond the last normal branch. The primary endpoint was the PAVM recanalization rate in selective or segmental pulmonary angiography performed 1 year post-embolization. RESULTS: The technical success rate of embolization juxta-proximal to the sac for simple-type PAVMs was 100%. None of the 19 lesions showed recanalization in pulmonary angiography performed 1 year after embolization. One patient experienced hemoptysis and pneumonia. CONCLUSION: Embolization of simple-type PAVMs' feeding vessel using AVP IV is safe and effective, with a high technical success rate and no recanalization on pulmonary angiography performed at 1 year post-embolization.

Predictors of futile recanalization after endovascular treatment of acute ischemic stroke.

OBJECTIVE: Endovascular therapy (EVT) is the most successful treatment for patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) in the anterior circulation. However, futile recanalization (FR) seriously affects the prognosis of these patients. The aim of this study was to investigate predictors of FR after EVT in patients with AIS. METHOD: Patients diagnosed with AIS due to anterior circulation LVO and receiving EVT between June 2020 and October 2022 were prospectively enrolled. FR after EVT was defined as a poor 90-day prognosis (modified Rankin Scale [mRS] score ≥ 3) despite achieving successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] classification of 2b-3). All included patients were categorized into control group (mRS score < 3) and FR group (mRS score ≥ 3). Demographic characteristics, comorbidities (hypertension, diabetes, atrial fibrillation, smoking, etc.), stroke-specific data (NIHSS score, ASPECT score and site of occlusion), procedure data (treatment type [direct thrombectomy vs. bridging thrombectomy], degree of vascular recanalization [mTICI], procedure duration time and onset-recanalization time), laboratory indicators (lymphocytes count, neutrophils count, monocytes count, C-reactive protein, neutrophil-to-lymphocyte ratio [NLR], monocyte-to-high-density lipoprotein ratio [MHR], lymphocyte-to-monocyte ratio [LMR], lymphocyte-to-C-reactive protein ratio [LCR], lymphocyte-to-high-density lipoprotein ratio[LHR], total cholesterol and triglycerides.) were compared between the two groups. Multivariate logistic regression analysis was performed to explore independent predictors of FR after EVT. RESULTS: A total of 196 patients were included in this study, among which 57 patients were included in the control group and 139 patients were included in the FR group. Age, proportion of patients with hypertension and diabetes mellitus, median NIHSS score, CRP level, procedure duration time, neutrophil count and NLR were higher in the FR group than in the control group. Lymphocyte count, LMR, and LCR were lower in the FR group than in the control group. There were no significant differences in platelet count, monocytes count, total cholesterol, triglycerides, HDL, LDL, gender, smoking, atrial fibrillation, percentage of occluded sites, onset-recanalization time, ASPECT score and type of treatment between the two groups. Multivariate logistic regression analysis demonstrated that NLR was independently associated with FR after EVT (OR = 1.37, 95%CI = 1.005-1.86, P = 0.046). CONCLUSION: This study demonstrated that high NLR was associated with a risk of FR in patients with AIS due to anterior circulation LVO. These findings may help clinicians determine which patients with AIS are at higher risk of FR after EVT. Our study can provide a theoretical basis for interventions in the aforementioned population.

Systemic Central Venous Rehabilitation in Congenital Heart Disease.

Chronic venous obstructions resulting from indwelling lines, surgery and instrumentation, and congenital anomalies are increasingly common in patients with congenital heart disease (CHD) and other chronic illnesses. Venous obstruction results in threatened long-term vascular access and congestive symptoms. Endovascular therapies are safe and can be effective at rehabilitating obstructed and even occluded veins. The risk of recurrent obstruction is high, however. Post-rehabilitation monitoring and anticoagulation therapy are important, and reinterventions are common. Here, the authors describe techniques to address a variety of venous obstruction lesions that may be encountered in CHD patients and provide illustrative cases.

Elevation of cardiac enzymes and B-type natriuretic peptides following venous recanalization and stenting in chronic venous obstruction.

BACKGROUND: B-type natriuretic peptides (BNP) and cardiac enzymes are both recognized biomarkers of heart health. Many studies have reported that using these indicators can assess cardiac condition and predict prognosis of patients undergoing surgery. Currently little is known on the effect of increased cardiac input after venous recanalization on cardiac physiology in patients with chronic venous obstruction (CVO). OBJECTIVES: The aim of this study was to explore the effect of iliocaval recanalization and stenting on cardiac biomarkers in patients with CVO. METHODS: This was a prospective study involving 60 patients in a single unit. Blood tests were collected 1 day before and 1 day after venous intervention. Three groups as group 1: patients with iliofemoral post-thrombotic syndrome (PTS) but without involvement of inferior vena cava (IVC) (n = 33); group 2: patients with iliofemoral PTS and involvement of IVC (n = 19) and group 3: patients with non-thrombotic vein lesion (NIVL) (n = 8) were compared based on cardiac biomarker levels. RESULTS: Median concentration of post-operative BNP (259.60 pg/mL) was greater than preoperative levels (49.80 pg/mL) [interquartile range (IQR), 147.15/414.68 versus 29.85/82.88; p < 0.001]. The levels of CK-MB [preop: 3 U/l (IQR, 1.40/11.00) versus postop: 14 U/l (IQR, 12/17), p < 0.001] and troponin T [preop: 3.00 pg/mL (IQR, 3.00/5.25) versus postop: level of 6 pg/mL (IQR, 3.00/9.50), p < 0.001]. Post-procedure increases in cardiac enzymes showed significant differences in BNP (p = 0.023) and troponin T (p = 0.007) across the three groups, while CK-MB levels were not significantly different (p > 0.05). Intergroup comparisons of postoperative BNP: group 1 versus group 2 (p = 0.013), group 2 versus group 3 (p = 0.029), group 1 versus group 3 (p = 0.834); and postoperative troponin T: group 1 versus group 2 (p = 0.018), group 2 versus group 3 (p = 0.002), group 1 versus group 3 (p = 0.282). According to multiple linear regression analysis, length of stenting and level of preoperative BNP were independent determinants of postoperative BNP levels (p < 0.05), and preoperative troponin T affected postoperative troponin T independently (p < 0.05). CONCLUSIONS: Troponin T, CK-MB and BNP seem to increase after venous recanalization and stent implantation, the elevation being more prominent for longer lesions.

Single Tract Aortic Revascularization Technique in the Treatment of Aortoiliac Occlusive Disease.

Endovascular treatment is an acceptable option for patients with aortoiliac occlusive disease. However, bilateral passage of guidewires through the aortoiliac occlusion can be a challenging step in achieving successful revascularization. The aim of this article is to present a novel strategy for successfully passing bilateral guidewires through long aortoiliac occlusive lesions. After one guidewire is passed through the aortic and iliac lesions via one side of the femoral artery, the other guidewire is passed using the up-and-over technique and pulled out from the ipsilateral side of the body. This contralateral guidewire is then inserted into the ipsilateral angiographic catheter along with the ipsilateral guidewire. Subsequently, the angiographic catheter is removed in a manner similar to a peel-away sheath. Eventually, bilateral guidewires can be passed through the lesion via a single aortic tract.

Predictive value of thrombus enhancement sign for stroke subtype and recanalization in acute basilar-artery occlusion.

BACKGROUND: Thrombus enhancement sign (TES) is associated with cardioembolic stroke and first-pass angiographic failure in anterior ischemic stroke. However, the relationship between TES and stroke subtype and recanalization status after endovascular treatment (EVT) in basilar artery occlusion (BAO) remains unknown. METHODS: This retrospective study included consecutive patients with acute BAO who underwent EVT between January 2020 and September 2023. Each patient underwent baseline non-contrast computed tomography (CT) and CT angiography. Two independent readers assessed the presence of TES. Stroke types were classified according to the Trial of ORG 10172 for Acute Stroke Treatment. Successful recanalization was defined as a modified Thrombolysis in Cerebral Infarction score of 2b-3 after EVT. Clinical and interventional parameters, along with histopathological thrombi examination results, were compared between the TES-positive and TES-negative groups. The associations between TES and stroke subtype and recanalization status were analyzed using univariate and multivariate analyses. RESULTS: A total of 151 patients were included in the analysis, among whom 116 (77%) exhibited TES. TES showed a significant correlation with cardioembolic and cryptogenic strokes (odds ratio [OR]: 8.56; 95% confidence interval: 3.49-22.4; p < 0.001), whereas the TES-positive thrombi were characterized by a higher fibrin/platelet proportion (p = 0.002) and lower erythrocyte proportion (p = 0.044). The TES-positive group demonstrated favorable outcomes compared to the TES-negative group, including a shorter procedure time (p < 0.001), lower number of thrombectomy attempts (p = 0.010), higher incidence of first pass success (p = 0.022), and lower rate of requiring rescue angioplasty and/or stenting (p < 0.001). In multivariate analysis, TES remained independently associated with successful recanalization (OR: 9.63; 95% CI: 2.33, 47.7; p = 0.003) after adjusting for baseline confounders. CONCLUSIONS: Visualization of TES serves as a reliable and easily accessible marker for identifying cardioembolic and cryptogenic strokes and predicting recanalization success in thrombectomy for basilar artery occlusion.

Introducing the Futile Recanalization Prediction Score (FRPS): A Novel Approach to Predict and Mitigate Ineffective Recanalization after Endovascular Treatment of Acute Ischemic Stroke.

Objective: This study aims to develop and validate the Futile Recanalization Prediction Score (FRPS), a novel tool designed to predict the severity risk of FR and aid in pre- and post-EVT risk assessments. Methods: The FRPS was developed using a rigorous process involving the selection of predictor variables based on clinical relevance and potential impact. Initial equations were derived from previous meta-analyses and refined using various statistical techniques. We employed machine learning algorithms, specifically random forest regression, to capture nonlinear relationships and enhance model performance. Cross-validation with five folds was used to assess generalizability and model fit. Results: The final FRPS model included variables such as age, sex, atrial fibrillation (AF), hypertension (HTN), diabetes mellitus (DM), hyperlipidemia, cognitive impairment, pre-stroke modified Rankin Scale (mRS), systolic blood pressure (SBP), onset-to-puncture time, sICH, and NIHSS score. The random forest model achieved a mean R-squared value of approximately 0.992. Severity ranges for FRPS scores were defined as mild (FRPS < 66), moderate (FRPS 66-80), and severe (FRPS > 80). Conclusions: The FRPS provides valuable insights for treatment planning and patient management by predicting the severity risk of FR. This tool may improve the identification of candidates most likely to benefit from EVT and enhance prognostic accuracy post-EVT. Further clinical validation in diverse settings is warranted to assess its effectiveness and reliability.

Innominate vein occlusion by the fabric of covered stent during transcatheter closure of sinus venosus defects - Causes, management, and outcome.

Transcatheter sinus venosus defect (SVD) closure with covered stents is emerging as an alternative to surgery. An adequate anchor zone in the superior vena cava is mandatory for the stability of the covered stent to prevent caudal embolization. There is a potential risk of innominate vein occlusion by the fabric of the covered stent in patients with a very short superior caval vein. Three among a total of 105 patients who underwent SVD closure at our institution developed innominate vein occlusion. Predisposing anatomical factors, identification and management of occluded innominate vein, and follow-up outcomes are discussed.

Reperfusion Injury-Postendovascular Recanalization in Chronic Mesenteric Ischemia: A Rare Clinical Case Scenario.

Regardless of the number of vessels involved endovascular recanalization of mesenteric vessels is the treatment of choice for chronic mesenteric ischemia. Reperfusion injury post-endovascular recanalization in chronic mesenteric ischemia is a rare clinical scenario as it is mostly encountered in cases of acute mesenteric ischemia. Here in, we describe a case with characteristic clinical and imaging findings of reperfusion syndrome, post-endovascular recanalization of chronically occluded superior mesenteric artery and severely stenosed celiac trunk in a patient with chronic mesenteric ischemia.

Efficacy of Superselective Intra-arterial Recanalization of Embolized Arteries Resulting from Facial Hyaluronic Acid Injection.

BACKGROUND: Arterial embolism is a rare complication caused by hyaluronic acid (HA) injection. However, it is one of the most serious complications. Once it happens, the complication would have a great and long-term impact on patients. Intra-arterial recanalization has been reported for recovering the visual acuity in patients with visual loss caused by hyaluronic acid. There is little report about the benefits of superselective intra-arterial recanalization therapy for skin wounds caused by hyaluronic acid vascular embolization. METHODS: Eight patients who had received the superselective intra-arterial recanalization therapy were retrospectively reviewed. Hyaluronidase was injected into the facial artery by superselective intra-arterial recanalization therapy, followed by symptomatic treatment. The facial artery recanalization was successfully performed and no interventional procedure-related adverse events happened. RESULTS: Arterial embolization accompanies by the interruption or reduction of blood supply, followed by ochrodermia, pain, numbness, swelling, yellowish white secreta and even necrosis on skin wound area. Early detection of skin blood supply disorders and early recovery of blood supply are very critical to treat facial artery embolization caused by HA. After superselective intra-arterial recanalization therapy, the blood supply to facial skin was restored and skin wounds recovered in all patients. Only 1 patient was left with small and superficial scars. CONCLUSION: Superselective intra-arterial recanalization therapy is an effective and safe method that can alleviate skin wounds caused by HA vascular embolization. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Factors predicting recanalization following stent-assisted coil embolization of unruptured intracranial aneurysms with long-term follow-up.

Objective: Stents have been widely used for coil embolization for intracranial aneurysms. Few studies have analyzed the risk factors of recanalization through long-term follow-up observation of only stent-assisted coiling. We analyzed the risk factors for recanalization through long-term observations. Methods: A total number of 399 unruptured aneurysms treated by stent-assisted coil embolization between 2003 and 2016 in a single institution were analyzed for determining the factors associated with recanalization including the patient characteristics, aneurysms, and procedural variables. All patients underwent angiographic follow-up with digital subtraction angiography or magnetic resonance angiography at 24 months or more following the procedure. Results: Recanalization occurred in 8%. The mean time for the recanalization was 21.1 ± 14.0 months (range, 5-51 months). The receiver operating characteristic curve analysis indicated areas under the curve for a maximum aneurysm size of 0.773 (cut-off, 6.415 mm). Multivariate analysis revealed that the maximum aneurysm size and parent artery curvature at which the aneurysm developed were significantly associated with recanalization. In parent artery curvature, the bifurcation group (OR, 9.02; 95% CI, 2.53-32.13; p = 0.001) and the convex group (OR, 3.68; 95% CI, 1.17-11.50; p = 0.025) were independent predictors of recanalization compared with the straight group. Conclusion: The maximum aneurysm size and parent artery curvature are risk factors associated with recanalization in stent-assisted coil embolization.

Endovascular Recanalization and Carotid Stenting: The New Approach to Restore Cerebral Perfusion during Aortic Dissection.

A type A aortic dissection (TAAD) is a dangerous condition requiring emergency surgery. Due to the similarity of the symptoms of cerebral malperfusion in TAAD and the signs of ischemic stroke, a differential diagnosis of these diseases is not always available. Patients with TAAD after cerebral malperfusion can have a neurological deficit. Thrombolysis is performed in this case. It can worsen the patient's condition and increase the risk of mortality and disability. The aim of the study is to evaluate the new approach to restoring cerebral perfusion during aortic dissection. This approach includes endovascular recanalization and carotid stenting. METHODS: Two clinical cases of TAAD complicated by cerebral malperfusion are described. The first patient is 73 years old and was admitted as planned to perform transcatheter aortic valve implantation (TAVI) for grade III aortic stenosis. The patient underwent transcatheter aortic valve implantation (TAVI) on the second day after admission. The second patient is 60 years old and was hospitalized by an ambulance with strong hypertension and ischemia. The surgical correction of aortic dissection was postponed until the neurological status assessment in both patients. RESULTS: The surgery to correct the aorta dissection was deemed inappropriate. The carotid arteries have been reanalyzed, and cerebral perfusion has been restored in a short time in both patients. CONCLUSION: Acute bilateral internal carotid occlusion is a potentially fatal TAAD outcome. Emergency endovascular recanalization and carotid stenting may be considered one of the few ways to restore cerebral perfusion.

Efficacy and safety of intravenous tenecteplase compared to alteplase before mechanical thrombectomy in acute ischemic stroke: a meta-analysis.

BACKGROUND: The benefits and risks of tenecteplase (TNK) versus alteplase (ALT) have recently been assessed in acute ischemic stroke (AIS) patients undergoing mechanical thrombectomy (MT) with diverse results. Due to its high fibrin specificity and lack of excitotoxicity, TNK may have a higher efficacy and safety profile. This study aimed to evaluate the benefits and risks of TNK compared to ALT in AIS patients prior to thrombectomy. METHODS: We systematically searched four key databases, PubMed, Embase, Web of Science and Cochrane Library until January 27, 2024 for clinical studies evaluating the effects of TNK versus ALT in patients with large vessel occlusion undergoing MT. A random-effect meta-analysis was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Ten studies involving 3722 patients receiving TNK (1266 patients) or ALT (2456 patients) were included (age: 69.05 ± 14.95 years; 55.64% male). Compared to ALT-treated patients, TNK-treated patients demonstrated significantly higher rates of early recanalization (odds ratio 2.02, 95%-confidence interval 1.20-3.38, p = 0.008) without increased risk of symptomatic intracerebral hemorrhage (1.06, 0.64-1.76, p = 0.82) or intracerebral hemorrhage (1.21, 0.66-2.25, p = 0.54). TNK-treated patients showed similar rates of functional independence at 90 days (1.13, 0.87-1.46, p = 0.37) as ALT-treated patients, but lower rates of mortality within 90 days (0.65, 0.44-0.96, p = 0.03). CONCLUSION: TNK is superior to ALT in achieving early recanalization and is associated with lower mortality within 90 days in AIS patients undergoing MT. Compared with ALT, TNK does not significantly alter functional independence at 90 days, symptomatic intracerebral hemorrhage or intracerebral hemorrhage.