Thrombus Removal Research Articles

Coronary artery aneurysm presenting as ST-elevation myocardial infarction in a man with coronavirus disease 2019: a case report

BackgroundPatients with underlying cardiovascular risk factors have worse clinical outcomes when they have coronavirus disease. In addition, a reduced workload of cardiovascular emergencies has been reported during the coronavirus pandemic due to patients’ reluctance to attend hospitals for fear of contracting the disease. Regional health service reorganization, separating hospitals into coronavirus and non-coronavirus can mitigate this effect. However, the effectiveness of this approach on outcomes and patient satisfaction is unknown.Case presentationA 35-year-old Pakistani man with acute ST myocardial infarction was found to have thrombosis of the right coronary artery aneurysm and concomitant coronavirus disease. He had percutaneous coronary angiography and thrombus removal, and was transferred to a coronavirus hospital for the management of the infection. Due to the large size of the aneurysm, he was considered for surgical intervention. Following discharge from the coronavirus hospital and a period of stay at the isolation center, he failed to keep his cardiology follow-up appointment.ConclusionThis case illustrates an unusual cause of myocardial infarction in a patient with coronavirus infection whose care may have been adversely affected by the healthcare system restructuring.

Time Trends of Ventricular Reconstruction and Outcomes among Patients with Left Ventricular Thrombus and Aneurysms.

Background: Clinical guidelines recommend surgical intervention when left ventricular thrombus (LVT) is complicated with left ventricular aneurysm (LVA). Objectives: This study aimed to review the changes in the treatment of LVT combined with LVA over the past 12 years at our center and to compare the efficacy of medical therapy and surgical treatment on patient outcomes. Methods: Between January 2009 and June 2021, 723 patients with LVT combined with LVA were enrolled, of whom 205 received surgical ventricular reconstruction (SVR) therapy and 518 received medical therapy. The following clinical outcomes were gathered via observation: all-cause death, cardiovascular death, and major adverse cardiovascular and cerebrovascular events (MACCEs; defined as the composite of cardiovascular death, ischemic stroke, and acute myocardial infarction). The median follow-up time was 1403 [707, 2402] days. Results: The proportion of SVR dropped yearly in this group of patients, from a peak of 64.5% in 2010 to 7.5% in 2021 (p for trend < 0.001). Meanwhile, the proportion of anticoagulant use increased quickly, from 8.0% in 2016 to 67.9% in 2021 (p for trend < 0.001). The incidence rates of all-cause mortality, cardiovascular death, and MACCEs were 12.9% (n = 93), 10.5% (n = 76), and 14.7% (n = 106), respectively. In the multivariable analysis, there were no significant differences in all-cause death (HR of 0.60, 95% CI of 0.32−1.13, p = 0.11), cardiovascular death (HR of 0.79, 95% CI of 0.41−1.50, p = 0.5), and MACCEs (HR of 0.82, 95% CI of 0.49−1.38, p = 0.5) between the two groups. The competing risk regression performed in the propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) analyses was in line with the unmatched analysis. Conclusions: The rate of SVR dropped significantly among patients with both LVT and LVA, while there was an improvement in oral anticoagulant utilization. SVR with thrombus removal did not improve all-cause mortality and cardiovascular outcomes in patients with LVT and LVA. Ventricular aneurysm with thrombus may not be an indication for surgery.

Evolution of deep vein thrombosis treatment from leeches to mechanical thrombectomy.

Deep vein thrombosis (DVT) is one of the most common diseases in developed countries with significant socioeconomic consequences. The severity of DVT lies in the potential for life-threatening pulmonary embolism and the development of chronic venous insufficiency, referred to as post-thrombotic syndrome. Virchow contributed to the understanding of the pathophysiological events that lead to thrombosis by describing three basic risk mechanisms. The first therapeutic attempts in the 17th century included venepuncture and the application of leeches. The first anticoagulant drug was heparin, which entered clinical practice after 1935. Subsequent commercialization of oral vitamin K antagonists (warfarin) and the advent of low molecular weight heparin along with compression therapy allowed the expansion of outpatient treatment of DVT. Recently, new oral anticoagulants have been introduced, leading to improved safety due to lower risk of bleeding complications and simplification of the treatment process. The next step in the development of therapeutic options are invasive methods of early thrombus removal, which significantly shorten the process and aim to reduce the occurrence of late complications. These methods include local catheter-directed thrombolysis using tissue plasminogen activator, mechanical thrombectomy and their combination called pharmaco-mechanical thrombectomy. The latter is currently used in patients with acute ilio-femoral DVT.

Risk factors for stent occlusion after catheter-directed thrombolysis and iliac vein stenting in the treatment of May-Thurner syndrome with iliofemoral deep vein thrombosis: a retrospective cohort study.

This study aimed to identify the risk factors for stent occlusion in patients with iliofemoral deep vein thrombosis (DVT) secondary to May-Thurner syndrome (MTS) who underwent catheter-directed thrombolysis (CDT) and iliac vein stenting. A retrospective analysis was performed on 44 patients who underwent CDT and iliac vein stenting for MTS with iliofemoral DVT between October 2001 and March 2018. MTS was diagnosed based on extrinsic compression of the left common iliac vein (CIV) by the overlying right common iliac artery (CIA) on computed tomography (CT). Clinical records of the study population were reviewed to collect baseline data, procedural characteristics, and outcomes. Final venograms showing diffuse and irregular wall thickening in the iliofemoral vein were considered to indicate a chronic post-thrombotic lesion. The stent position was categorized as follows: confluence coverage without touching the contralateral inferior vena cava (IVC) wall, IVC extension contacting the contralateral IVC wall, or distal to the iliocaval junction. Stent patency was assessed using duplex ultrasonography. Risk factors for stent occlusion were assessed using univariate and multivariate Cox proportional hazard models. The median duplex ultrasound follow-up period was 25 months (range, 1-196 months). The overall cumulative patency rate at 12 months was 70.0%. In the univariate Cox regression, factors significantly associated with stent occlusion included symptom duration >2 weeks before CDT, partial thrombolysis (50-99% of thrombus removal), chronic post-thrombotic lesions, and stent position. Multivariate Cox regression showed that chronic post-thrombotic lesions [hazard ratio (HR) =7.15; 95% confidence interval (CI): 1.32-38.81; P=0.023] and a stent distal to the iliocaval junction (HR =5.59; 95% CI: 1.46-21.38; P=0.012) were significantly associated with stent occlusion. Chronic post-thrombotic lesion and a stent distal to the iliocaval junction were important risk factors for stent occlusion in patients who underwent CDT and iliac vein stenting.

Acute interventions-dialysis shunt recanalization

An arteriovenous fistula is vital for patients who need regular hemodialysis. Continuous patency and sufficient functionality determine quality of life and associated morbidity and mortality of patients. Following successful hemodialysis shunt creation, intimal hyperplasia and consecutive thrombosis or complete occlusion may cause different types of shunt dysfunctionality or even critical failure. Immediate shunt recanalization and revision by using an endovascular-first approach is crucial for long-term survival of hemodialysis fistula. There are several mechanisms available for catheter-based thrombus removal to unmask the typically underlying shunt stenosis. Primary technical recanalization success rates are very similar for clot cleaning. Treatment of intimal hyperplasia is preferably addressed by using drug-coated balloon angioplasty to allow for increased shunt patency compared to plain old balloon angioplasty. Stents and stent grafts are only used for resistant or repeated short-term recurrence of severe stenosis. Finally, surgical revision has a classical role in case of repeated failure of endovascular measures.

The Importance of Early Thrombus Removal

Historically, anticoagulation has been the primary treatment for acute lower extremity deep venous thrombosis (DVT) with or without thrombolysis. Despite large amounts of clinical research data supporting an ‘open vein hypothesis’, which favours early thrombus removal, clinicians have been hesitant to take this option due to a historically high risk of major bleeding and a few notable studies that failed to show any meaningful benefit. The ATTRACT trial failed to show the benefit of using pharmacomechanical catheter-directed thrombolysis (PCDT) for iliofemoral and femoropopliteal DVT but did result in more bleeding. However, the CaVent study before it revealed a significant reduction in post-thrombotic syndrome (PTS) for patients with iliofemoral and femoral DVT after long-term follow-up past 24 months that grew over time. Since these trials, there have been significant advancements in magnetic resonance and CT venography, intravascular ultrasound (IVUS), venous stenting and thrombectomy catheters meaning there is little to no need for adjunct thrombolytics. Results from ongoing research such as CLEAR-DVT reflect the advances in modern technology.

Abstract 14358: A Rare Case of Refractory Ventricular Arrhythmias Caused by Subacute Aortic Root Thrombosis Following Left Ventricular Assist Device

Introduction: Aortic Root thrombus (ART) is relatively uncommon complication following left ventricular assist device (LVAD) therapy with significant morbidity and mortality. Case: A 51-year-old male with coronary artery disease with CABG (LIMA to LAD and sequential SVG) presented with acute cardiogenic shock. EKG showed right bundle branch block with diffuse T wave inversions. Coronary angiogram showed severe three vessel disease with occlusion of all vein grafts except LIMA-LAD. Patient subsequently underwent LVAD with HM3 implant placement as a destination therapy. He was started on warfarin with heparin drip as a bridge. Post op course was complicated by recurrent VF storm. Patient was started on amiodarone and lidocaine. A transthoracic echocardiogram showed LVAD inflow cannula in place and aortic valve was noted to be closed with every beat. HM3 speed was decreased to 5500 rpm. Patient continued to have recurrent episodes of VF, refractory to cardioversion and anti-arrhythmic agents. CT angiogram showed aortic root filling defect consistent with thrombosis extending from the leaflets towards the Sino tubular junction, along the left coronary cusp leaflets. Patient eventually required VT ablation for refractory ventricular arrhythmia. Patient underwent median sternotomy for surgical removal of aortic root thrombus which showed parts of the thrombus intimately connected to the aortic root wall including the left main and right coronary ostia. Post op patient was continued on systematic anticoagulation with noted clinical improvement. Conclusion: ART after LVAD placement is a rare complication and can be associated with myocardial infarction and thromboembolic events. It can compromise coronary perfusion and result in ischemic ventricular arrhythmias as seen in our case. Management includes surgical removal of the pump or orthoptic heart transplantation. VT ablation should be considered if no ischemic culprit identified

Evolution of open aneurysmorrhaphy for management of sac expansion after endovascular repair of abdominal aortic aneurysms

ObjectiveWe evaluated the perioperative and mid-term clinical outcomes of open aneurysmorrhaphy (OA) for the treatment of sac expansion after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms. MethodsOA involves sac exposure without dissection of the proximal or distal neck, sacotomy and ligation of back-bleeding vessels, preservation of the prior stent graft, and tight closure of the sac around the stent graft. We performed a retrospective review of all patients who had undergone OA for nonruptured sac expansion after standard EVAR at our institution between January 2015 and June 2021. The primary end points were 30-day mortality and aneurysm-related death. The secondary end points were postoperative complications, overall survival, freedom from reintervention, and sac regrowth rate. ResultsA total of 28 patients had undergone OA. Their mean age was 76.9 ± 6.7 years. The median sac diameter at OA was 79 mm (interquartile range [IQR], 76-92 mm). The median duration from the index EVAR to OA was 82 months (IQR, 72-104 months). Preoperative computed tomography angiography confirmed a type II endoleak (EL) in 20 patients, 1 of whom had had a coexisting type Ia EL; a type IIIb EL was identified in 1 patient. Concomitant endovascular procedures had been performed in six patients to treat a type I or III EL or reinforce the proximal and distal seals. The OA technique has been modified since 2017, with the addition of more aggressive dissection of the sac and complete removal of the mural thrombus to further decrease the sac diameter. Postoperative complications occurred in two patients and included abdominal lymphorrhea and failed hemostasis of the common femoral artery requiring surgical repair in one patient each. The 30-day mortality was 0%. During the median follow-up of 36 months (IQR, 14-51 months), the overall survival was 92.7% and 86.9% at 12 and 36 months, respectively, without any aneurysm-related death. In the late (2017-2021) treatment group, the median sac diameter immediately after OA was smaller than that in the early (2015-2016) treatment group (early group: median, 50 mm; IQR, 39-57 mm; vs later group: median, 41 mm; IQR, 32-47 mm; P = .083). Furthermore, in the late group, the sac regrowth rate was lower (early group: median, 0.36 mm/mo; IQR, 0.23-0.83 mm/mo; vs late group: median, 0 mm/mo; IQR, 0-0.11 mm/mo; P = .0075) and the freedom from reintervention rate was higher (late group: 94.7% at both 12 and 36 months, respectively; early group: 71.4% and 53.6% at 12 and 36 months, respectively; log-rank P = .070). ConclusionsOur results have shown that OA for the management of post-EVAR sac expansion is feasible with acceptable mid-term outcomes. Aggressive dissection and tight plication of the sac might be imperative for better mid-term outcomes after OA.

Unexpected find of native aortic leaflet thrombus during surgical myocardial revascularization.

A 47-year-old woman was referred from a regional hospital for surgical myocardial revascularization after non-ST-elevation myocardial infarction. Medical history reported dyslipidaemia, hypothyroidism, endometriosis surgery, and a family history of thromboembolism. Coronary angiogram and transthoracic echocardiography (TTE) performed 13 days earlier showed two-vessel coronary disease with severe stenosis of the left anterior descending (LAD), diagonal and marginal arteries, and preserved left-ventricular ejection fraction (LVEF = 55%) without significant valve disease. Intraoperative transoesophageal echocardiography (iTEE) showed a large mass attached to the aortic non-coronary leaflet and sinus of Valsalva (Panel A, white star), with reduced leaflet motion but no valvular hemodynamic dysfunction (Panel A). The mass was closely attached to and moving with the leaflet, but clear cleavage planes with the leaflet and the aortic root were observable (Panel A, white triangles). An organized thrombus secondary to an initial lesion by the catheter during coronary angiogram was suspected, and confirmed by the macroscopic and histological examination (Panel B). The thrombus was completely removed, and myocardial revascularization by sequential left internal thoracic graft to the diagonal and LAD as well as radial Y-graft to the marginal artery was performed. Post-bypass iTEE examination showed complete thrombus removal and normal motion of the leaflet (Panel C). On the basis of familial history of thrombus, our consultant haematologist recommended oral anticoagulation therapy with warfarin until results of blood coagulation disorder tests are obtained. The patient was discharged 6 days after surgery without significant post-operative complication.

Thrombectomy using aspiration catheter- An effective first line approach for resistant thrombi in patient of acute myocardial infarction

Acute myocardial infarction is caused by the rupture or erosion of an atherosclerotic plaque, initiating intra-luminal thrombosis resulting in partial or complete occlusion of a coronary artery. Primary percutaneous coronary intervention (PCI) is the preferred treatment and is effective in opening the infarct-related artery. These results can be further improved with thrombus aspiration which reduces stent thrombosis and improves myocardial blush. In acute presentation, there is a high load of thrombus in the infarct-related artery and stent placement in such a case increases the chances of the thrombus shifting both proximally and distally in the microvasculature. In such patient, deferred stenting along with the attempt of thrombus aspiration has the potential for complete thrombus removal with improvement in TIMI flow which eliminates the need of stenting. Here, we present an interesting case report pertaining to the feasibility of multiple thrombus aspiration attempts (&amp;#62;25) as first approach in young patient (Male/32 years/no co-morbidities) with late presentation of STEMI and a large resistant thrombus load on an angiogram. We also re-assessed the need of stenting after 5 days of thrombus aspiration attempt along with continued anticoagulation from the first contact with patient.

In vivo evaluation of histopathologic findings of vascular damage after mechanical thrombectomy with the Tromba device in a canine model of cerebral infarction.

A novel stent retriever device for in vivo mechanical thrombectomy for acute cerebral infarction has been developed. In this study, we compared the thrombus removal capacity, potential complications, and extent of vessel wall damage of this novel device with those of the Solitaire FR device by performing a histopathologic analysis using an autopsied canine model. Through this experimental evaluation, we aimed to assess the safety and efficacy of the newly developed thrombus removal device for cerebral infarction. Blood clots (autologous thrombus) were injected into 12 canines. Mechanical thrombectomy was performed in six canines using the newly developed Tromba thrombectomy device (experimental group) and in the other six canines using the Solitaire FR thrombectomy device (control group). Angiographic and histopathologic evaluations were performed 1 month after the blood vessels underwent mechanical thrombectomy. In the experimental group, the reperfusion patency was classified as "no narrowing" in five cases and "moderate narrowing (25%-50% stenosis)" in one case. In the control group, the reperfusion patency was classified as "no narrowing" in four cases, "moderate narrowing (25%-50% stenosis)" in one case, and "slight narrowing (less than 25% stenosis)" in one case. In the experimental group, intimal proliferation was observed in only two cases, endothelial loss was observed in two cases, and device-induced medial injury was observed in one case. In the control group, intimal proliferation was observed in two cases, endothelial loss was observed in one case, and thrombosis (fibrin/platelet) was observed in one case. The Tromba thrombectomy device showed no significant difference to the conventional Solitaire device in angiographic and histopathologic evaluations after thrombus removal. The stability and efficiency of the newly developed Tromba device are considered to be high and comparable to those of Solitaire.

Impact of a blood return system on mechanical thrombectomy-associated blood loss and hemodynamic outcomes in a pulmonary embolism registry

Abstract Background Mechanical thrombectomy can treat pulmonary embolism (PE) while eliminating the bleeding risks associated with thrombolytic-based therapies. In longer and more complex procedures, however, blood loss from aspiration-based mechanical thrombectomy can potentially limit thrombus removal. Purpose Assess a blood return system's ability to reduce mechanical thrombectomy procedure blood loss and characterize hemodynamic outcomes post-procedure. Methods This retrospective analysis of a prospective, multicentre, real-world registry enrolling intermediate- and high-risk PE patients treated with mechanical thrombectomy compared all patients enrolled prior to the availability of a blood return system with all patients whose treatment included use of a blood return system. Linear regression was used to model the blood return system's effect on estimated blood loss. The model was adjusted for patient characteristics and disease factors that may have been different between the treatment groups or related to blood loss. Results Complete case analysis was used to identify 319 patients prior to the availability of a blood return system (no blood return), and 50 patients who were treated using a blood return system through January 2022 (blood return). As shown in Table 1, the only significant differences in the summary statistics for the blood return group were 160 ml decreased estimated blood loss (292.5 to 132.5 ml; p&amp;lt;0.01) and a 13.1 minute increase in thrombectomy time (47.9 to 61.0 minutes; p&amp;lt;0.01). Linear regression modeling revealed that use of a blood return system was associated with a 200 ml (69%) reduction (p&amp;lt;0.01) in blood loss for the average patient and thrombectomy time (Figure 1A). Importantly, the addition of an interaction term between thrombectomy time and blood return showed blood loss reduction increased with thrombectomy time (Figure 1B). Post-procedure mean pulmonary arterial pressure decreased by 7.0 mmHg (33.0 to 26.0 mmHg) in the blood return group and 7.9 mmHg (32.1 to 24.2 mmHg) in the no blood return group. In patients with depressed baseline cardiac index (CI) &amp;lt;2, CI improved by 0.3 L/min/m2 (1.8 to 2.1 L/min/m2) in the blood return group and 0.4 L/min/m2 (1.6 to 2.0 L/min/m2) in the no blood return group, demonstrating normalization of depressed CI in both groups. No hemodynamic outcomes differed significantly between groups (p&amp;gt;0.05). Conclusions Treatment with aspiration mechanical thrombectomy in combination with a blood return system achieved equivalent hemodynamic outcomes compared with mechanical thrombectomy alone, while reducing 69% of procedure blood loss. The fact that blood return patients had equivalent hemodynamic improvements suggests these improvements are related to thrombus removal rather than aspiration-related blood loss. The association identified between blood loss and thrombectomy time indicates that thrombus removal is not limited by blood loss when a blood return system is used. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Inari Medical

Initial experience with a continuous mechanical aspiration system for thrombus removal before percutaneous coronary intervention.

Here we investigate the safety and efficacy of a continuous mechanical aspiration system when used before percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS). Historically, trials of routine manual aspiration thrombectomy in ACS patients have reported mixed results. This may be due to the technical limitations of manual aspiration, which suffers from decreasing vacuum power as aspiration is performed. This is a retrospective case series of all patients treated with continuous mechanical aspiration (Indigo CAT RX Aspiration System; Penumbra Inc.) before PCI between August 2017 and July 2020 at five centers in the United States. Data regarding angiographic assessments, procedure, and safety were examined. Seventy-two patients (mean age 60 ± 12.5 years, 34.7% female) with ST Elevation Myocardial Infarction (STEMI) (80.6%) or Non-ST Elevation Myocardial Infarction (NSTEMI) (19.4%) were included. Target vessels were the right coronary (43.1%), left anterior descending (33.3%), and left circumflex (23.6%). Preprocedure, 94.4% had a high thrombus burden (thrombolysis in myocardial infarction [TIMI] thrombus grade ≥ 3). Median aspiration time was 35 s and median access-to-reperfusion time was 10 min. After CAT RX alone, 86.1% had complete perfusion (TIMI flow grade 3). After the procedure, 94.4% had TIMI thrombus grade <3% and 97.2% had TIMI flow grade 3. There were no cases of ischemic stroke. Cardiovascular mortality at 30 days was 1.4%. In our initial experience, aspirating thrombus from ACS patients using the Indigo CAT RX Aspiration System before PCI was safe and effective for reducing thrombus burden and restoring flow.

WHERE ARE YOU GOING: EMERGENCY MANAGEMENT OF A THROMBUS-IN-TRANSIT WITH PERCUTANEOUS MECHANICAL THROMBECTOMY AT A COMMUNITY HOSPITAL

WHERE ARE YOU GOING: EMERGENCY MANAGEMENT OF A THROMBUS-IN-TRANSIT WITH PERCUTANEOUS MECHANICAL THROMBECTOMY AT A COMMUNITY HOSPITAL

INTRACEREBRAL HEMORRHAGE POSTPHARMACOMECHANICAL CATHETER-DIRECTED THROMBOLYSIS: CAN WE PREVENT IT?

INTRACEREBRAL HEMORRHAGE POSTPHARMACOMECHANICAL CATHETER-DIRECTED THROMBOLYSIS: CAN WE PREVENT IT?

Endovascular Management of Acute Iliofemoral Deep Vein Thrombosis: Who Benefits?

Endovascular therapy (ET) for acute lower extremity deep vein thrombosis (DVT) to mitigate downstream postthrombotic syndrome (PTS) has garnered considerable attention, reflected by the significant growth in clinical interest and proliferation of venous-specific thrombectomy devices. Numerous single-arm or retrospective studies examining the role of DVT thrombolysis/thrombectomy have been published. However, the landmark Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) trial is the largest and most rigorous investigation to date on whether ET, particularly pharmacomechanical catheter-directed thrombectomy/thrombolysis (PCDT), resulted in the prevention of PTS (1).

Machine learning-based prediction of the post-thrombotic syndrome: Model development and validation study.

BackgroundPrevention is highly involved in reducing the incidence of post-thrombotic syndrome (PTS). We aimed to develop accurate models with machine learning (ML) algorithms to predict whether PTS would occur within 24 months.Materials and methodsThe clinical data used for model building were obtained from the Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis study and the external validation cohort was acquired from the Sun Yat-sen Memorial Hospital in China. The main outcome was defined as the occurrence of PTS events (Villalta score ≥5). Twenty-three clinical variables were included, and four ML algorithms were applied to build the models. For discrimination and calibration, F scores were used to evaluate the prediction ability of the models. The external validation cohort was divided into ten groups based on the risk estimate deciles to identify the hazard threshold.ResultsIn total, 555 patients with deep vein thrombosis (DVT) were included to build models using ML algorithms, and the models were further validated in a Chinese cohort comprising 117 patients. When predicting PTS within 2 years after acute DVT, logistic regression based on gradient descent and L1 regularization got the highest area under the curve (AUC) of 0.83 (95% CI:0.76–0.89) in external validation. When considering model performance in both the derivation and external validation cohorts, the eXtreme gradient boosting and gradient boosting decision tree models had similar results and presented better stability and generalization. The external validation cohort was divided into low, intermediate, and high-risk groups with the prediction probability of 0.3 and 0.4 as critical points.ConclusionMachine learning models built for PTS had accurate prediction ability and stable generalization, which can further facilitate clinical decision-making, with potentially important implications for selecting patients who will benefit from endovascular surgery.

Direct carotid artery puncture for acute ischemic stroke: Local experience and systematic review.

To establish surgical access during endovascular treatment of ischemic stroke, femoral artery puncture is most commonly performed followed by a small number of radial artery access procedures. However, there are few reports of carotid artery puncture. We report the case of an 87-year-old woman who was admitted to hospital with hemiplegia of the left limb and loss of consciousness for 40 min, accompanied by urinary incontinence. After complicated transfemoral and transradial attempts, the patient underwent emergency direct carotid artery puncture (DCAP) for the treatment of acute ischemic stroke. We reviewed the literature on this topic over a 7-year period (September 2014 to April 2022), including 202 patients with acute ischemic stroke who underwent emergency DCAP and endovascular surgery. The average age of these patients was 80.5 years. The left DCAP accounted for 52.5% (106/202) of the cases. Local anesthesia was utilized in 33.9% (64/189) of the cases. Angio-Seal was utilized for closure in 53.7% (79/147) of the patients. About half (105/199) of the patients recovered or improved their limb function after DCAP. Postoperative complications were mainly neck hematoma and one of these patients died due to a fatal neck hematoma. We describe the detailed procedure of the rare case of an emergency DCAP performed at our institution. DCAP provides an alternative treatment method in cases where thrombus removal access cannot be established through traditional methods.

Path planning and optimization for micro-robot in a vessel-mimic environment

Manipulating micro-robots in blood vessels is an essential technology for medical researchers in applications such as drug delivery and thrombus removal. The usage of micro-robots in medicine can help overcome the limitations of many conventional clinical methods. In this study, we aimed to make the micro-robot more intelligent while moving through blood vessels. First, the skeleton of an image of the blood vessels is extracted, which is further used for path planning. Then, the skeleton-extraction-based A* algorithm was used for determining a best route for the movement of the microrobot at a safe distance from the vascular wall. Finally, the gradient descent algorithm was utilized to smooth the planned path. Simulations were conducted to verify the effectiveness of the proposed algorithms. The proposed methods would improve the efficiency for the further manipulation of the micro-robot in the blood vessel environment.

Study on the mechanism of thrombus ablation in vitro by burst-mode femtosecond laser.

The burst-mode femtosecond laser has the potential to be a novel thrombus removal technique. This paper proposed to investigate the mechanism of thrombus ablation in vitro by burst-mode femtosecond laser. A simulation model of the interaction between femtosecond laser and thrombus was established. An in vitro thrombus model was prepared. Combined with the high-speed galvanometer and femtosecond laser, the ablation experiments in vitro were performed. The experimental results showed that the ablative threshold was 0.27 times and the efficiency was about 1.4 times of burst-mode femtosecond laser as those of traditional mode femtosecond laser. These phenomena were related to the residual temperature and free electrons on the thrombus surface, which confirmed the simulating results and had relationship with incubation effects. The high ablative efficiency and safety of burst-mode femtosecond laser for thrombus ablation were verified, which may help to achieve the femtosecond pulse output through flexible fiber easily and stably. The burst-mode femtosecond laser represents an important technological advancement of the method in terms of endovascular treatment with femtosecond laser.