Flow Arrest Research Articles

Abstract WP111: The Role of Intravenous Tissue Plasminogen Activator in Acute Ischemic Stroke With Large Vessel Occlusion

Introduction: Current guidelines recommend administration of intravenous tissue plasminogen activator (IVT) for all eligible patients with acute ischemic stroke (AIS) with large vessel occlusion (LVO). Recent observational data question the safety and efficacy of IVT in AIS patients with LVO undergoing mechanical thrombectomy (MT). Methods: Retrospective analysis using prospectively collected database on all AIS patients with LVO treated at our institution over 3 consecutive years. Stroke outcomes and adverse events were compared between patients who underwent IVT+MT versus MT only. Stroke outcomes were adjusted for known comorbidities, last know well time and core volume on pretreatment imaging. Results: 158 AIS patients with LVO were treated. 69 patients had treatment strategy of IVT+MT, 89 patients MT only. 7 (10%) patients treated with IVT had successful reperfusion before MT. IVT+MT, compared with MT alone, was associated with reduced 90day mortality (22.4% vs 40.8%, p:0.03) and reduced 90day severe disability or death (mRS 4-6: 48% vs 67%, p:0.03). Door-to-puncture time (DTP) was longer with IVT. IVT was not associated with increased intracranial hemorrhage but was associated with increased access site hematomas (16.9% vs 5.7%, p:0.03). Both groups showed similar proportion of patients ≥TICI2c (IVT+MT: 48% vs MT: 47%), however IVT+MT patients had greater proportion of TICI2c than TICI3. (IVT+MT TICI2c:30.4% vs MT TICI2c:17%) Conclusions: IVT before MT in AIS with LVO, results in reperfusion prior to thrombectomy in 10% of patients, and is associated with reduced mortality and severe disability at 90days. However, IVT+MT is associated with more access site hematomas and increased TICI 2C vs TICI 3 reperfusion, suggesting increased distal embolization due to thrombus fragmentation. The use of balloon guide for proximal flow arrest and aspiration during thrombectomy should be considered.

Development of an in vitro model of calcified cerebral emboli in acute ischemic stroke for mechanical thrombectomy evaluation

​BackgroundCalcified cerebral emboli (CCEs) are a rare cause of acute ischemic stroke (AIS) and are frequently associated with poor outcomes. The presence of dense calcified material enables reliable identification of...

Embolization of a Complex Facial Arteriovenous Malformation, Balloon-Assisted Flow Arrest, and Controlled n-BCA Injection with Dextrose Push Technique: 2-Dimensional Operative Video.

N-butyl cyanoacrylate glue (n-BCA, Cerenovus, Irvine, California) is commonly used to treat arteriovenous malformation (AVM). Even though Onyx (ethylene vinyl alcohol, Medtronic, Dublin, Ireland) presents more controlled injection, n-BCA is colorless, thus preferable for treatment of superficial facial malformations. N-BCA injection into AVM can result in premature distal migration or early precipitation and reflux into the feeder vessels. Here we describe a trans-arterial balloon assisted technique embolization of a complex facial AVM with n-BCA. A 22-yr-old female with chronic oral/gum bleeding presented with a complex facial AVM. She underwent selective transarterial n-BCA balloon assisted treatment with dextrose push. Informed written consent was obtained. A Scepter dual lumen balloon (MicroVention, Aliso Viejo, California) and a Prowler microcatheter (Cerenovus) were introduced via a 6-French Envoy guide catheter (Cerenovus) selectively into the AVM feeder. The balloon was positioned 3 cm proximal to the Prowler microcatheter tip and fully inflated to create flow arrest. Diluted 25% concentration of n-BCA in Ethiodol Oil was injected through the Prowler microcatheter. The distal migration of the n-BCA was modulated with simultaneous injection of Dextrose 5% in water via the Scepter balloon. This resulted in a controlled glue injection without early distal glue migration (because of the flow arrest) nor early proximal glue precipitation or reflux (because of the dextrose infusion), obtaining complete cure of the complex facial AVM. Glue embolization with flow arrest and dextrose push allows well controlled injection, and it represents a valid option also for high flow vascular lesions.

Commentary: Embolization of a Complex Facial Arteriovenous Malformation, Balloon-Assisted Flow Arrest, and Controlled n-BCA Injection With Dextrose Push Technique: 2-Dimensional Operative Video.

Commentary: Embolization of a Complex Facial Arteriovenous Malformation, Balloon-Assisted Flow Arrest, and Controlled n-BCA Injection With Dextrose Push Technique: 2-Dimensional Operative Video.

Management of patients with isolated acute cervical carotid artery occlusion and normal neurological exam: Technical note and case series

ObjectivesLimited data exists on the management and outcome of patients with isolated acute cervical internal carotid artery (cICA) occlusion presenting with normal neurologic exam after experiencing a period of neurological deficits. These patients are at risk for progressive neurologic deterioration but have not yet progressed to stroke. Current management is no intervention due to intervention risk of embolization. We aim to determine the optimal management of patients with isolated acute cICA occlusion presenting with a normal neurological exam after experiencing neurological deficits. Patients and methodsData was collected on 3 patients with acute cICA occlusion that presented with a normal neurological exam to our institution. Patient 1 was treated according to standard protocol, while patients 2 and 3 were treated according to the management discussed. Associations between perfusion imaging studies and clinical outcome were analyzed to determine stroke risk. A revascularization technique to minimize risk of distal embolization is described. ResultsA total of 3 consecutive patients with acute cICA occlusion were successfully revascularized. Patients 2 and 3 (66.67%) were neurologically intact post-operatively, while patient 1 (33.33%) had residual hemiparesis. It seems that MTT ≥ 200% or Tmax > 6 s is the optimal penumbra threshold predicting infarction and neurologic deterioration. There were no embolic complications as a result of endovascular therapy (EVT). ConclusionCerebral perfusion imaging of patients presenting with normal neurological exam after experiencing neurological deficits is warranted to help identify patients at risk for stroke due to collateral failure. These patients should be monitored in the ICU for neurologic deterioration and given the option of intervention if mismatch is noted on CT perfusion imaging. Perfusion studies identifying penumbra and delayed MTT ≥ 200% or Tmax > 6 s are indicators for possible collateral failure. In patients undergoing intervention, we suggest a technique using proximal flow arrest to minimize risk of shower emboli. Further studies are needed to verify our findings.

Role of Balloon Guide Catheter in Modern Endovascular Thrombectomy.

Proximal flow control achieved with a balloon guide catheter (BGC) during endovascular treatment of acute ischemic stroke is reviewed in this article. In clinical practice, BGCs offer a multi-faceted approach for clot retrieval by creating proximal flow arrest, reducing embolic burden, and shortening procedure time. Evaluation of frontline thrombectomy procedures with BGCs revealed advantages of combined use over the conventional guide catheter (CGC), notably in the significant reduction of distal emboli to both the affected and previously unaffected territories. Recently, new measures of early and complete reperfusion at first thrombectomy pass have been identified as independent predictors of improved outcomes, which were consistently demonstrated with use of BGC as a safe and effective option to minimize number of passes during intervention. Prior randomized controlled trials reported the positive correlation between BGC-treated patients and a lower risk of mortality as well as shortened procedure time. While BGC use is more common in stent retriever-mediated mechanical thrombectomy, preliminary data has shown the potential benefit of device application during contact aspiration thrombectomy to achieve successful recanalization. However, the question of which major endovascular strategy reigns superior as a frontline remains to be answered. Along with clinical case assessments, BGC performance during in-vitro simulation was analyzed to further understand mechanisms for optimization of thrombectomy technique.

Safety and Efficacy of Flow Reversal in Acute and Elective Carotid Angioplasty and Stenting Using the Mo.Ma Device with Short-Term Follow-Up

Objective: To determine the safety and efficacy of flow reversal following proximal flow arrest as an embolic protection strategy for carotid angioplasty and stenting (CAS) with short-term follow-up. Method: We performed a retrospective review of our CAS database for patients who underwent stent-supported carotid revascularization in the setting of acute/subacute stroke or TIA. We reviewed clinical and radiographic data during a 36-month period. Primary outcome was clinical evidence of ipsilateral stroke in the first 30 days. Secondary outcomes include clinical outcomes and sonographic and/or angiographic follow-up over 6 months, 6-month functional scale, and all-cause mortality. Results: Fifty-five patients underwent CAS using flow reversal: 26 females and 29 males with a mean age of 69.7 years. Median time to treatment from index event was 3 days. 11% underwent stenting as part of hyperacute stroke therapy. Average luminal stenosis was 86%. The 9-Fr Mo.Ma device was used in combination with Penumbra aspiration in all cases. There were no ipsilateral strokes. Incidence of any ischemic event was 3.64%, but only 1 (1.82%) patient had a postoperative stroke. Clinical follow-up was available for 94.5%, while lesion follow-up was available for 73% of patients. Three patients had evidence of restenosis, but none were symptomatic. Luminal restenosis was ≤30% in all three. Median pre- and post-NIHSS were 1 and 1, respectively. Conclusion: Flow reversal using the Mo.Ma device is a safe and effective strategy in preventing distal embolization during carotid artery revascularization.

Flow Arrest in the Plasma Membrane

The arrangement of receptors in the plasma membrane strongly affects the ability of a cell to sense its environment both in terms of sensitivity and in terms of spatial resolution. The spatial and temporal arrangement of the receptors is affected in turn by the mechanical properties and the structure of the cell membrane. Here, we focus on characterizing the flow of the membrane in response to the motion of a protein embedded in it. We do so by measuring the correlated diffusion of extracellularly tagged transmembrane neurotrophin receptors TrkB and p75 on transfected neuronal cells. In accord with previous reports, we find that the motion of single receptors exhibits transient confinement to submicron domains. We confirm predictions based on hydrodynamics of fluid membranes, finding long-range correlations in the motion of the receptors in the plasma membrane. However, we discover that these correlations do not persist for long ranges, as predicted, but decay exponentially, with a typical decay length on the scale of the average confining domain size.

Efficacy of Combining Proximal Balloon Guiding Catheter and Distal Access Catheter in Thrombectomy with Stent Retriever for Anterior Circulation Ischemic Stroke.

ObjectiveWe evaluated efficacy of combining proximal balloon guiding catheter (antegrade flow arrest) and distal access catheter (aspiration at the site of occlusion) in thrombectomy for anterior circulation ischemic stroke. MethodsWe retrospectively analyzed 116 patients who underwent mechanical thrombectomy with stent retriever. The patients were divided by the techniques adopted, the combined technique (proximal balloon guiding catheter and large bore distal access catheter) group (n=57, 49.1%) and the conventional (guiding catheter with stent retriever) technique group (n=59, 50.9%). We evaluated baseline characteristics (epidemiologic data, clinical and imaging characteristics) and procedure details (the number of retrieval attempts, procedure time), as well as angiographic (thrombolysis in cerebral infarction (TICI) score, distal thrombus migration) and clinical outcome (National Institutes of Health Stroke Scale at discharge, modified Rankin Scale [mRS] at 3 months) of them. ResultsThe number of retrieval attempts was lower (p=0.002) and the first-pass successful reperfusion rate was higher (56.1% vs. 28.8%; p=0.003) in the combined technique group. And the rate of final result of TICI score 3 was higher (68.4% vs. 28.8%; p<0.01) and distal thrombus migration rate was also lower (15.8% vs. 40.7%; p=0.021) in the combined technique group. Early strong neurologic improvement (improvement of National Institutes of Health Stroke Scale ≥11 or National Institutes of Health Stroke Scale ≤1 at discharge) rate (57.9% vs. 36.2%; p=0.02) and favorable clinical outcome (mRS at 3 months ≤2) rate (59.6% vs. 33.9%; p=0.005) were also better in the combined technique group. ConclusionThe combined technique needs lesser attempts, decreases distal migration, increases TICI 3 reperfusion and achieves better clinical outcomes.

Evaluation of the Intracranial Flow Alteration during Manual Syringe and Continuous Pump Aspiration

GoalsWhile mechanical thrombectomy (MT) has been shown to be effective in the treatment of acute large vessel occlusions, adjunctive measures, such as balloon guide catheters (BGC) and aspiration techniques, are utilized heterogeneously. Clarifying the effects of aspiration applied to the anterior cerebral circulation with proximal flow arrest can shed light on embolic protection during MT. Materials and MethodsManual and pump aspiration were applied through a BGC in a synthetic cerebrovascular model with a 60 ml syringe and a Penumbra pump, respectively. Flow direction was observed during the procedure with fluorescent particles and ultraviolet light. Flow rates were monitored at the simulated internal carotid artery and middle cerebral artery (MCA). FindingsBoth aspiration methods produced retrograde flow in all the modeled cerebrovascular segments. In the syringe aspiration methods, an interval phase occurred during the experimental trial in which suction forces paused and MCA flow became anterograde through posterior communication artery collateral circulation. ConclusionFlow patterns vary with different methods of aspiration. With proximal flow arrest, continuous aspiration methods induce constant retrograde flow in all vessels, whereas manual aspiration demonstrates various flow changes, including periods of anterograde flow during the procedure, which may be less effective at distal re-embolization prevention.

Real-time Monitoring of Cerebral Blood Flow and Cerebral Oxygenation During Rapid Ventricular Pacing in Neurovascular Surgery: A Pilot Study

Rapid ventricular pacing (RVP) can be used to produce short periods of flow arrest during dissection or rupture of a cerebral aneurysm but carries the risk of inducing cerebral ischemia. This study evaluates the intraoperative effect of RVP on local cerebral blood flow (CBF) and cerebral oxygenation during neurovascular surgery. Five patients undergoing elective cerebrovascular surgery were included in a single-center prospective study. RVP was applied in pacing periods of 40 seconds with 30% and 100% FiO2. Regional cerebral oxygenation was monitored using a Foresight near-infrared spectroscopy sensor. A Clark-type electrode and a thermal diffusion microprobe located in the white matter were used to monitor brain tissue pO2 and CBF, respectively. CBF response to RVP closely followed the blood pressure pattern and resulted in a low-flow state. Unlike CBF, brain tissue pO2 and regional cerebral oxygenation showed a delayed response to RVP, decreasing beyond the pacing period and slowly recovering after RVP cessation. We found a correlation between brain tissue pO2 and regional cerebral oxygenation. Increasing the inspired oxygen concentration had a positive impact on absolute regional cerebral oxygenation and brain tissue pO2 values, but the pattern resulting from applying RVP remained unaltered. RVP reduces CBF and cerebral oxygenation. Brain tissue pO2 and regional cerebral oxygenation are correlated but unlike CBF respond to RVP in a delayed manner. Further research is required to evaluate the impact of longer RVP bursts on brain oxygenation.

ANCD thrombectomy device: in vitro evaluation

IntroductionEndovascular treatment of stroke, although highly effective, may fail to reach complete recanalization in around 20% of cases. The Advanced Thrombectomy System (ANCD) is a novel stroke thrombectomy device designed...

Neuroform Atlas stent in treatment of iatrogenic dissections of extracranial internal carotid and vertebral arteries: a single-centre experience.

To present our experience in the treatment of iatrogenic dissections of extracranial internal carotid and vertebral arteries with the Neuroform Atlas stent. Between January 2017 and February 2018 we treated iatrogenic dissections of three internal carotid arteries and three vertebral arteries. These iatrogenic dissections occurred during the endovascular treatment of ruptured and unruptured intracranial aneurysms. The indication for stenting was haemodynamically significant, flow-limiting dissection with threatening flow arrest. In all six cases, the dissections were treated by placement of Neuroform Atlas stents in the dissected segments of internal carotid or vertebral arteries. Deployment of the stent was followed by the usual dual antiplatelet regimen. Single or multiple Neuroform Atlas stents were deployed without any technical difficulties, and blood flow was restored immediately after placement of the stents in all six cases. Midterm follow-up (6-8 months) showed complete reconstruction of the shape and lumen of all treated arteries, with negligible intimal hyperplasia. Our results indicate that a favourable outcome can be achieved by treating iatrogenic dissections of extracranial internal carotid and vertebral arteries with the Neuroform Atlas stent.

Adenosine-Assisted Management of Intracranial Aneurysm

AbstractCerebral aneurysms can be complex and variable in size, position, and morphology, resulting in difficult surgical exposure and secure clip placement. They have a high mortality rate when ruptured, and though endovascular techniques have emerged to tackle this, surgical clip ligation remains the preferred modality for some aneurysms. Various techniques that help the surgeon dissect the aneurysmal dome and apply the clip are temporary clip ligation of proximal vessels, deep hypothermic circulatory arrest, and balloon suction decompression. All of them require significant logistics and result in increased morbidity and mortality. Adenosine is a suitable alternative for inducing a temporary flow arrest, causing a short period of controlled hypotension. Its rapid onset and offset property along with low incidence of adverse events makes it an ideal agent in this regard. We present here a review on its use, contraindications, safety profile, and future applications.

Vertebral Artery Patency and Thrombectomy in Basilar Artery Occlusions.

Background and Purpose- Factors influencing recanalization success in basilar artery occlusions are largely unknown. Preliminary evidence has suggested that flow arrest in the vertebral artery contralateral to the catheter bearing vertebral artery may facilitate recanalization. The aim of this analysis was to assess the impact of anatomic variations and flow conditions on recanalization success in basilar artery occlusion treated with mechanical thrombectomy. Methods- Consecutive basilar artery occlusions treated with second-generation thrombectomy devices at a single-center were retrospectively analyzed. Baseline patients' characteristics, occlusion length, collateral circulation, underlying stenosis, incomplete occlusions, and patency of the vertebral arteries were analyzed with regards to recanalization success. Aplastic or hypoplastic vertebral artery contralateral to the catheter position was defined as contralateral low flow condition. Logistic regression analysis was used to examine the association between anatomic variations and flow conditions in relation to complete recanalization and the modified Rankin Scale score while controlling for several potentially confounding variables. Clinical impact was evaluated using the modified Rankin Scale score of ≤3. Results- One hundred fifteen patients were included (mean age 71.5±12.8, m:f=2:1, median National Institutes of Health Stroke Scale =15, interquartile range =10-22). Complete recanalization was more often observed in patients with contralateral low flow conditions (80.6% versus 50.0%), which remained an independent predictor of complete recanalization in multivariable analysis (adjusted odds ratio, 5.81; 95% CI, 1.97-17.19). Patients with complete posterior recanalization had lower in-hospital mortality (16.4% versus 41.7%) and more often achieved modified Rankin Scale score of ≤3 (49.4% versus 8.3%), even after adjusting for potential confounders (adjusted odds ratio, 15.93; 95% CI, 1.42-179.00). Conclusions- Contralateral low flow condition (vertebral artery aplasia or hypoplasia) seems to be an independent factor for fewer distal emboli and complete recanalization in basilar artery occlusion patients treated by modern endovascular devices. Complete recanalization reflecting the absence of peri-interventional clot fragmentation brings clear clinical benefit. Further studies are warranted to evaluate the need for contralateral flow modulation or ipsilateral balloon guide catheter during posterior circulation thrombectomy in patients with bilaterally patent vertebral arteries.

Direct Cervical Carotid Stenting and Angioplasty of Right Internal Carotid Artery and Brachiocephalic Artery Ostial Stenoses With Flow Reversal: 2-Dimensional Operative Video.

We present a case of tandem stenosis of the great vessels (cervical internal carotid artery [ICA] and brachiocephalic trunk ostium [BTO]) treated with stenting and balloon angioplasty of both lesions under flow arrest. A 70-yr-old woman with a history of hypertension, hyperlipidemia, coronary artery disease, and previous strokes presented with recurrent transient ischemic attacks of the left upper and lower extremities over the last 6 mo. She underwent right cervical endarterectomy (CEA) 16 yr prior. Neurological examination was unremarkable. Carotid Doppler ultrasonography revealed severely increased velocities of the right ICA. Cervical magnetic resonance angiography demonstrated 80% right ICA stenosis and 50% BTO stenosis. Digital subtraction cerebral angiography showed 80% right ICA stenosis and 70% BTO stenosis. The patient was not a candidate for standard carotid artery stenting because the BTO precluded endovascular access or for CEA because of the previous CEA; therefore, direct carotid access and flow reversal was an alternative. Under general anesthesia and systemic heparinization, the patient underwent right carotid artery surgical exposure. Under flow reversal using the Enroute System (Silk Road Medical, Sunnyvale, California), anterograde right ICA stenting angioplasty and retrograde BTO stenting and angioplasty were performed. Successful revascularization of the right ICA and BTO was obtained. No procedure-related complications occurred. The patient was discharged home 2 d postprocedure, neurologically intact. Direct carotid access with flow reversal is a safe and effective therapeutic alternative for patients with ICA (or common carotid artery) stenosis who cannot undergo CEA or when endovascular access from the aortic arch is not possible. Patient consent was obtained prior to performing the procedure. Institutional board approval is not required for the report of a single case.

Microsurgical Resection of Ruptured Large Left Temporo-Occipital Arteriovenous Malformation: 3-Dimensional Operative Video.

A 59-yr-old man presented with intraventricular hemorrhage and was found to have a large temporo-occipital arteriovenous malformation (AVM), Spetzler-Martin grade 4. The preoperative intra-arterial digital subtraction angiography (IADSA) showed the AVM was 4×4 cm2, had superficial and deep venous drainage, and was fed by multiple branches of the posterior cerebral artery and middle cerebral artery. Preoperative embolization was done in 4 stages. He underwent a left temporo-occipital craniotomy, mastoidectomy, and retrosigmoid craniotomy with a posterior temporal approach. Intraoperatively, there was a large draining vein draining into the sigmoid sinus in the location of the vein of Labbe, and multiple other feeding arteries and draining veins, including periventricular vessels. Circumferential dissection of the AVM was done from posteriorly, superiorly, anteriorly, and then inferiorly. The technique of temporary clipping and cauterizing the perforating arteries, and then sectioning them after flow arrest is shown in the video. Large arterial feeders were cauterized and divided. Three permanent aneurysm clips were left to control bleeding from the vessels of the trigone of the lateral ventricle. After the large draining vein into the sigmoid sinus was occluded, the AVM was completely removed. The patient had acute nonfluent aphasia postoperatively but improved after speech therapy. The postoperative IADSA demonstrated total resection. At 3-mo follow-up, he had recovered completely (mRS0). This 3-D video shows the technical nuances of microsurgical resection of a complex large AVM. Informed consent was obtained from the patient prior to the surgery that included videotaping of the procedure and its distribution for educational purposes. All relevant patient identifiers have also been removed from the video and accompanying radiology slides.

Spinal Cord Infarction in the Region of the Posterior Spinal Artery After Embolization for Vertebral Artery Dissection.

Endovascular surgery for vertebral artery dissections (VADs) carries the risk of spinal cord infarction (SCI). Although SCI in the region of the anterior spinal artery (ASA) has been reported, SCI in the region of the posterior spinal artery (PSA) is rare. To investigate PSA infarction after endovascular surgery for VAD. Infarction in the region of the PSA after endovascular surgery for VADs carried out in consecutive 21 cases was investigated. The variables of aneurysmal location, status, intra-aneurysmal thrombosis, antithrombotic therapy, and endovascular procedure were investigated in relation to the occurrence of spinal cord or brain stem infarction. Thirteen cases were unruptured aneurysms, and 8, ruptured aneurysms. The endovascular surgical method was internal trapping in 10 cases, stent-assisted coil embolization in 8 cases, and proximal occlusion (PO) in 3 cases. Periprocedural symptomatic infarction was detected in 4 of the 21 cases (19%): 3 SCIs and 1 lower medulla infarction, after 1 stent-assisted coil embolization and 3 PO. All 3 symptomatic SCIs were PSA infarction. On univariate analysis, the variables of posterior inferior cerebellar artery-involved-type, PO, and intraprocedural proximal flow arrest were significantly correlated with occurrence of PSA infarction. PSA infarction after endovascular surgery for VAD seems not to be a rare potential complication. Insufficiency of collateral blood flow and artery-to-artery embolism due to intraprocedural flow stagnation of the VA seem to be the possible mechanisms of PSA infarction in addition to previously reported mechanisms such as direct obliteration by the embolic materials and extended thrombosis of the VA stump.

Further Development of Combined Techniques Using Stent Retrievers, Aspiration Catheters and BGC : The PROTECTPLUS Technique.

First pass complete (mTICI3) reperfusion must be regarded as the ultimate goal in mechanical thrombectomy (MT) in patients suffering from an emergent large vessel occlusion (ELVO). With this in mind atechnical modification of the previously published PROTECT (PRoximal balloon Occlusion TogEther with direCt Thrombus aspiration during stent retriever thrombectomy) approach, the PROTECTPLUS technique was evaluated. Under proximal flow arrest using aballoon guide catheter (BGC), astent retriever was only partially inserted into alarge-bore aspiration catheter. This construction was subsequently retracted as aunit into the BGC with aspiration both at the aspiration catheter and at the BGC. Acase-control study was performed comparing the PROTECT technique with the PROTECTPLUS technique with respect to the technical and procedural parameters. Patients n = 165 (101 PROTECT, 64PROTECTPLUS) with ELVO of either the terminus of the internal carotid artery or the proximal middle cerebral artery were included. Using the PROTECTPLUS resulted in ahigher rate of first pass complete reperfusions (59.4% vs. 27.7%, p < 0.001) as compared with PROTECT. The PROTECTPLUS also led to shorter procedure times (21 min vs. 37 min, p = 0.001) and higher rates of overall complete reperfusion (73.5% vs. 49.5%, p = 0.014) compared to PROTECT. The PROTECTPLUS technique is apromising technical modification to further optimize endovascular stroke treatment.

The Influence of Short-Term Occlusion on Dynamics of Arterial Circulation in Calf Muscles

Research background and hypothesis. KAATSU training is a method based on workout in a local hypoxic environment. For the justifi cation of its a detailed vascular response to circulatory disturbances is required.Research aim. The aim of this study was to investigate the peculiarities of reactive hyperaemia depending on the duration of occlusion and preliminary fi lling with blood of the occluded limb.Research methods. Arterial blood-fl ow intensity was measured by vein-occlusion plethysmography after 1, 2, and 3 minutes of occlusions. When the occlusion cuff was quickly infl ated with air above 250 mmHg, the amount of blood in vessels was close to the conditions of physiological norm. While the leg was lifted above the heart level for 30 seconds, the amount of blood in the calf decreased. A slow blowing the air into the cuff created a situation when the amount of blood in vessels had increased before the blood-fl ow was arrested. Research results. The peak blood-fl ow in the reactive hyperaemia phase depends on the duration of the occlusion and on the degree of fi lling with blood of segment under occlusion. The peak blood-fl ow readings were registered after occlusions conducted when the amount of blood in the limb had decreased before the occlusion and the lowest blood-fl ow readings was registered after occlusion done with the increased fi lling of vessels. Discussion and conclusions. The initial fi lling of vessels with blood or the degree of tension of endothelial cells of vascular wall is the most signifi cant infl uence on blood fl ow activation after short-term occlusions.Keywords: blood flow arrest, reactive hyperaemia, occlusion plethysmography.