Effectiveness of mechanical recanalization for intraluminal occlusion of totally implantable venous access ports

Purpose: To evaluate if the mechanical injection of saline is effective in restoring patency of a totally implantable venous access port (TIVAP) with an intraluminal occlusion. Materials and methods: From January 2017 to June 2019, 64 cases of dysfunction of a TIVAP were referred to interventional radiology. Among these, 16 cases showed normal function of the TIVAP, 19 cases the showed the appearance of a fibroblastic sheath, and 29 cases showed intraluminal occlusion. Mechanical recanalization was performed for intraluminal occlusion of the TIVAP with an indeflator and a 20G non-coring needle. Linograms were performed in all recanalized cases. The success or failure of recanalization and the pressure of the indeflator were recorded. Linograms were evaluated for breakage or migration of catheters. Medical records were retrospectively reviewed. Results: Among the 29 intraluminal occlusion cases, 24 cases (82.7%) were recanalized by mechanical recanalization via an indeflator. The pressure of the indeflator ranged from 29 to 220 psi (median: 118 psi). Linograms revealed breakage of the catheter of the TIVAP in two failed cases. The median interval from implantation to dysfunction was 405 days (range: 43–1723 days). The median interval from last use to dysfunction was 8 days (mean: 15.4 days; range: 1–119 days). The median re-occlusion free period after successful mechanical recanalization was 100.5 days (range: 6–859 days). Conclusion: In the absence of an available thrombolytic agent, mechanical injection of saline was a tolerable alternative method for restoring occluded catheters and sustaining the function of catheters. Because breakage of the catheter can occur during mechanical recanalization of a TIVAP, a linogram should follow the procedure.

Case of successful hybrid revascularization and limb salvage in patient with CLI after multiply ABF thrombosis and absence of outflow arteries

Patients with CLI often present multilevel disease. They underwent multiply revascularization procedures aiming to save thelimb. The main obstacle is absence or poor outflow arteries. Inability to restore bloodflow usuallyleads to ischemia progression and consequent amputation. We describe two cases of successful treatment of patient with CLI after multiply ABF thrombosis and absence of outflow arteries.The first 63 years old patient developed the third case of ABF thrombosis as a result of profunda and superficial femoral arteries chronic occlusion. We performed mechanical recanalization and angioplasty of anterior tibial, popliteal, subintimal recanalization and angioplasty of superficial femoral arteries. After that the ABFleg was sutured to subintimal space of femoral artery. The next case was another 63 years old patient with total chronic occlusion of iliac, femoral, popliteal and tibioperoneal trunk. We performed mechanical recanalization and angioplasty of anterior tibial, popliteal, subintimal recanalization and angioplasty of superficial femoral arteries. And then extra anatomy femoro-femoral autovenous bypass, distal anastomosis was performed by using subintimal artery space also. Thelong term period was 27 months for the first case and 20 months - for the second one. All bypasses were patient.Therefore this described above approach of hybrid open and endovascular surgery could give additional chance forlowlimb revascularization in this so-called hopeless group with criticallimb ischemia.

Endovascular stroke treatment using balloon guide catheters may reduce penumbral tissue damage and improve long-term outcome

Objectives During mechanical recanalization of large vessel occlusions (LVO), the use of proximal flow arrest with balloon guide catheters (BGC) was shown to be associated with better angiographic and even clinical outcome. The aim of the study was to analyze the impact of BGC use on microstructural alterations in the salvaged penumbra. Methods All patients who underwent mechanical recanalization of LVO of the anterior circulation were reviewed within a prospective stroke registry of a single comprehensive stroke center. Fifty-two patients received an admission CT perfusion together with post-interventional diffusion tensor imaging. Technical details such as BGC usage were correlated with microstructural integrity changes of the salvaged gray matter through the mean diffusivity (MD) index. Moderation analysis was performed to test the interaction of BGC on the correlation between angiographic and clinical outcomes. Results For all patients with complete reperfusion, microstructural integrity changes with lowered MD index were found within the salvaged penumbra for cases of non-BGC usage (mean − 0.02) compared to cases with BGC usage (0.01, p = 0.04). The importance of complete reperfusion for good clinical outcome is predominantly based on patients treated with BGC (effect 2.78, p = 0.01 vs. for non-BGC: 0.3, p = 0.71). Conclusions The lowered MD index early after mechanical recanalization without BGC usage can be interpreted as microstructural ischemic damage of the salvaged penumbra. It was shown that achieving complete reperfusion in a setting of BGC usage with proximal flow arrest minimizes penumbral damage and improves long-term outcomes. Key Points • Microstructural ischemic damage can be reduced by using proximal flow arrest during endovascular treatment with balloon guide catheter. • Complete reperfusion in a setting of balloon guide catheter minimizes penumbral damage and improves long-term outcome.

Thrombus Histology of Basilar Artery Occlusions

Background For patients with acute vessel occlusions of the anterior circulation histopathology of retrieved cerebral thrombi has been reported to be associated to stroke etiology. Due to the relatively small incidence of posterior circulation stroke, exclusive histopathologic analyses are missing for this subgroup. The aim of the study was to investigate thrombus histology for patients with basilar artery occlusions and uncover differences to anterior circulation clots with respect to underlying etiology. Methods A total of 59 basilar thrombi were collected during intracranial mechanical recanalization and quantitatively analyzed in terms of their relative fractions of the main constituents, e.g. fibrin/platelets (F/P), red (RBC) and white blood cells (WBC). Data were compared to histopathological analyses of 122 thrombi of the anterior circulation with respect to underlying pathogenesis. Results The composition of basilar thrombi differed significantly to thrombi of the anterior circulation with an overall higher RBC amount (median fraction in % (interquartile range):0.48 (0.37–0.69) vs. 0.37 (0.28–0.50), p < 0.001) and lower F/P count (0.45 (0.21–0.58) vs. 0.57 (0.44–0.66), p < 0.001). Basilar thrombi composition did not differ between the different etiological stroke subgroups. Conclusion The results depict a differing thrombus composition of basilar thrombi in comparison to anterior circulation clots with an overall higher amount of RBC. This may reflect different pathophysiologic processes between anterior and posterior circulation thrombogenesis, e.g. a larger proportion of appositional thrombus growth in the posterior circulation.

Mechanical recanalization for acute bilateral cerebral artery occlusion – literature overview with a case

BackgroundAcute bilateral internal carotid artery (ICA) and/or middle cerebral artery (MCA) occlusion is extremely rare and associated with poor clinical outcomes. There are only a few reports in the literature about mechanical thrombectomy being performed for acute bilateral occlusions. The treatment strategies and prognoses (clinical outcomes) are therefore unclear.MethodsA systematic review of the literature was performed through several electronic databases with the following search terms: acute bilateral stroke, mechanical recanalization and thrombectomy.ResultsIn the literature, we identified five reports of six patients with bilateral ICA and/or MCA occlusion treated with mechanical recanalization. Additionally, we report our experience with a subsequent contralateral large brain artery occlusion during intravenous thrombolytic therapy, where the outcome after mechanical thrombectomy was not dependent on the time from stroke onset but rather on the capacity of collateral circulation exclusively.ConclusionsAcute bilateral cerebral (ICA and/or MCA) occlusion leads to sudden severe neurological deficits (comas) with unpredicted prognoses, even when mechanical recanalization is available. As the collateral capacity seems to be more important than the absolute time to flow restoration in determining the outcomes, simultaneous thrombectomy by itself probably does not lead to improved functional outcomes.

Diffusion-weighted Imaging Reversibility In Stroke After Successful Mechanical Recanalization. Case report

Increased use of Diffusion-weighted imaging (DWI) in acute stroke has led to observations of early diffusion normalization in lesions thatinitially show diffusion slowing. The “renormalization” of DWI may be spontaneous or the result of thrombolytic therapy, thus, acuteslowing of diffusion is not necessarily an indicator of irreversible tissue damage. The perfusion-diffusion mismatch concept is attractiveas it assumes that DWI lesion size reflects the infarct core whilst the mismatch area reflects the penumbra. However, this concept maybe an oversimplification. This paper shows a case with Diffusion Lesion Reversal after successful neuroendovascular treatment andexcellent clinical outcome, and discuss the imaging characteristics associated with this phenomenon.

Preventing vessel perforations in endovascular thrombectomy: feasibility and safety of passing the clot with a microcatheter without microwire: the wireless microcatheter technique

BackgroundTo place a stent retriever for thrombectomy in acute ischemic stroke, the clot has to be passed first. A microwire is usually used for this maneuver. As an alternative, a wireless microcatheter can be used to pass the clot.ObjectiveTo analyze the feasibility and complication rates of passing the clot using either a microwire or a wireless microcatheter.MethodsA retrospective non-randomized analysis of 110 consecutive patients with acute ischemic stroke in the anterior circulation was performed, in whom video recordings of mechanical thrombectomies were available. In total, 203 attempts at mechanical recanalization were performed.ResultsSuccessful recanalization (TICI 2b–3) was achieved in 97.3% of patients. In 71.8% of attempts the clot was successfully passed using a wireless microcatheter only. When a microwire was used initially, clot passage was successful in 95.3% of attempts. Complication rates for angiographically detectable subarachnoid hemorrhage were 6.1% when a microwire was used to pass the clot compared with 0% when a wireless microcatheter was used (p<0.001). Complication rates for angiographically occult circumscribed subarachnoid contrast extravasation observed on post-interventional CT scans were 18.2% when a microwire was used to pass the clot and 4.5% when a wireless microcatheter was used (p<0.001).ConclusionsIn most cases of mechanical recanalization the clot can be passed with a wireless microcatheter instead of a microwire. In our study this method significantly reduced the risk for vessel perforation and subarachnoid hemorrhage. We therefore recommend the use of this technique whenever possible.