Effectiveness of the preventive administration of vasoactive amines in counterbalancing significant patient blood pressure drops following nimodipine administration during mechanical thrombectomy procedures

BACKGROUND

Focal vasospasm (FV) of the occluded vessel can occur during the endovascular treatment of acute ischemic stroke (AIS). Nimodipine is commonly used to treat vasospasm and can play a role in distinguishing it from artery narrowing due to iatrogenic dissection or residual clot. However, nimodipine administration can result in arterial hypotension and subsequent enlargement of the ischemic core.

OBJECTIVE

To assess the efficacy of preventive and continuous vasoactive amine infusion to counterbalance nimodipine-induced hypotension.

METHODS

We reviewed data from a prospective registry of patients treated for AIS between January 2019 and January 2022 who were administered nimodipine. All patients were equipped with an arterial cannula for invasive blood pressure measurement and given vasoactive amines preemptively before general anesthesia and throughout the procedure. Data obtained from invasive monitoring of mean arterial blood pressure (MABP) in a time-lapse of 25 min before and after nimodipine administration were analyzed.

RESULTS

MABP significantly decreased after nimodipine administration but remained within the recommended range (81.79 ± 0.49 mmHg). Nimodipine was effective in reducing FV caused by stent retriever passage in 76.3% of cases. Furthermore, it proved valuable in diagnosing iatrogenic dissection (9.2%), residual clot (10.5%), or intracranial stenosis (4%).

CONCLUSIONS

Infusion of vasoactive amines effectively counteracted the intraarterial nimodipine effect, thus avoiding frank arterial hypotension during endovascular treatment. Nimodipine has been useful in differentiating the diagnosis of FV resulting from mechanical thrombectomy and other potential causes, such as iatrogenic dissection or residual clot.

Adhesion of vessel wall to stentriever during combined technique for mechanical thrombectomy in acute ischemic stroke: A histomorphological study

PURPOSE

Detection of vessel wall tissue in thrombus material in patients with ischemic stroke is judged as vascular injury. So far, several studies investigated components of the free clots after mechanical thrombectomy. The aim of this retrospective study was to investigate the involvement and role of the stentriever in vessel wall injury by analysis of the composition of adherent tissue to the stentriever during combined aspiration thrombectomy with stentriever.

METHODS

Stentriever with adherent tissue and free clots in aspiration samples from patients undergoing mechanical thrombectomy (aspiration plus stentriever) were separately assessed for the occurrence of parts of vascular tissue together with clinical and interventional data as well as clinical outcome data. Specimens were analyzed histomorphologically and immunohistochemically. Findings, focused on parts of vessel wall were reported together with clinical data.

RESULTS

Specimens from 21 identified patients were available. Parts of the vessel wall were detected in 7 out 21 (33%) samples. All specimens revealed fresh thrombus material without signs of organization or atheromatous tissue. In 90% of patients mTICI was greater than 2b without signs of secondary vessel injury. No vascular tissue was found in free clots of the aspiration samples.

CONCLUSION

The examination of adherent tissue to the stentriever instead of the examination of free clots may affect the number of detected parts of vessel wall. Further studies in combination with vessel wall imaging may elucidate the origin of remnants of vessel wall.

Branch-site occlusion sign predicts the embolic origin of acute ischemic stroke: a meta-analysis

Objective

The study aimed to investigate whether branch-site occlusion (BSO) sign could predict the etiology of acute intracranial large artery occlusion (ILVO) and the stentriever (SR) response.

Methods

We systematically reviewed studies that evaluated the predictive role of BSO for the etiology of ILVO-AIS or EVT outcome between 1 January 2000 and 31 August 2022 from PubMed, Embase, and Web of Science.

Results

The sensitivity and specificity of BSO sign predicting etiology of ILVO-AIS were 0.87 (95% CI 0.81-0.91) and 0.64 (95% CI 0.33-0.87), respectively. The sensitivity and specificity of BSO sign predicting stentriever response were 0.84 (95% CI 0.63-0.94) and 0.61 (95% CI 0.18-0.92), respectively.

Conclusion

The BSO sign could be a valid and precise imaging marker to predict embolism caused ILVO-AIS and recanalization success by SR without rescue therapy.

Endovascular treatment strategies for simultaneous bilateral anterior circulation occlusions in acute ischemic stroke: A single-center experience and systematic review of the literature

BACKGROUND

Bilateral and simultaneous occlusion of the anterior circulation is a rare event in patients with acute ischemic stroke. Although endovascular treatment is feasible and safe, the endovascular strategy to be used remains a subject of debate.

OBJECTIVE

To assess the different endovascular strategies proposed for the treatment of a bilateral, simultaneous anterior circulation occlusion following acute ischemic stroke.

METHODS

We present a retrospective study of the clinical and radiological records of all patients with a bilateral, simultaneous anterior circulation occlusion treated at our center between January 2019 and December 2022. Following the PRISMA guidelines, we also conducted a systematic review of the literature.

RESULTS

Two patients with a bilateral and simultaneous middle cerebral artery occlusion were treated at our center during the study period. A TICI score ≥2b was obtained in 4 out of 4 occlusions. Modified Rankin Scale (mRS) at 90 days was 0 and 4, respectively. The literature review retrieved reports on 22 patients. The most frequent bilateral occlusion sites were internal carotid artery-middle cerebral artery. The clinical presentation was severe in most patients. A combined thrombectomy technique proved to have the highest number of first-pass recanalization. A TICI ≥2b was obtained in 95% of patients and an mRS ≤2 was found in 31.8% of patients.

CONCLUSIONS

In patients with bilateral and simultaneous occlusion of the anterior circulation, endovascular treatment using a combined technique appears to be rapid and effective. The clinical evolution of this patient population strongly depends on the severity of the onset symptoms.

In Vitro Comparison of Several Thrombus Removal Tools

BACKGROUND

Although the routine use of thrombus aspiration is not recommended, the thrombectomy technique still might be considered for a selected population of patients. Therefore, the assessment of the effectiveness of commercially available thrombectomy devices is still clinically relevant.

AIM

Here, we present an in vitro comparison of several different types of catheters that can be used for thrombus aspiration or removal.

METHODS

Through the removal of 6 h and 24 h human blood clots in an in vitro model, four catheters were compared: the Launcher, Pronto V4, Vasco+ and the stent-retriever Catchview. The aspiration efficacy was expressed as a percentage of the initial thrombus weight. The effectiveness of the patient's aspiration was dependent on the time of thrombus formation and was significantly higher for a thrombus formed over 24 h (58.5 ± 26.5%) than for one formed over 6 h (48.0 ± 22.5%; p < 0.001). In the presented in vitro model, Pronto V4 and Launcher showed the highest efficiency.

CONCLUSIONS

Large-bore aspiration catheters were found to be more effective than narrow-bore catheters or stent-retrievers in an in vitro model of thrombus removal. The thrombus aspiration efficacy increases with longer thrombus formation times.

Nomogram to Predict the Number of Thrombectomy Device Passes for Acute Ischemic Stroke with Endovascular Thrombectomy

Purpose

This study aimed to determine the risk factors associated with the number of thrombectomy device passes and establish a nomogram for predicting the number of device pass attempts in patients with successful endovascular thrombectomy (EVT).

Methods

We enrolled patients from a signal comprehensive stroke center (CSC) who underwent EVT because of large vessel occlusion stroke. Multivariate logistic regression analysis was used to develop the best-fit nomogram for predicting the number of thrombectomy device passes. The discrimination and calibration of the nomogram were estimated using the area under the receiver operating characteristic curve (AUC-ROC) and a calibration plot with a bootstrap of 1000 resamples. A decision curve analysis (DCA) was used to measure the availability and effect of this predictive tool.

Results

In total, 130 patients (mean age 64.9 ± 11.1 years; 83 males) were included in the final analysis. Age (odds ratio [OR], 1.085; 95% confidence interval [CI], 1.005-1.172; p = 0.036), baseline Alberta Stroke Program Early computed tomography (ASPECTS) score (OR, 0.237; 95% CI, 0.115-0.486; p < 0.001), and homocysteine level (OR, 1.090; 95% CI, 1.028-1.155; p = 0.004) were independent predictors of device pass number and were thus incorporated into the nomogram. The AUC-ROC determined the discrimination ability of the nomogram, which was 0.921 (95% CI, 0.860-0.980), which indicated good predictive power. Moreover, the calibration plot revealed good predictive accuracy of the nomogram. The DCA demonstrated that when the threshold probabilities of the cohort ranged between 5.0% and 98.0%, the use of the nomogram to predict a device pass number > 3 provided greater net benefit than did "treat all" or "treat none" strategies.

Conclusion

The nomogram comprised age, baseline ASPECTS score, and homocysteine level, can predict a device pass number >3 in acute ischemic stroke (AIS) patients who are undergoing EVT.

Comparison of the Solitaire and Trevo Stents for Endovascular Treatment of Acute Ischemic Stroke: A Single.Center Experience

Aims

Limited studies have compared the effectiveness of Solitaire and Trevo stentrievers for endovascular thrombectomy to achieve recanalization and improve functional outcomes of patients with acute ischemic stroke. Therefore, we compared the safety and efficacy of the two stents during endovascular thrombectomy for patients with acute ischemic stroke.

Materials and Methods

This study included 130 patients who underwent endovascular thrombectomy using either the Trevo (n = 51) or the Solitaire (n = 79) stent for anterior circulation acute ischemic stroke. Recanalization was classified using thrombolysis in cerebral infarction (TICI) grading. Efficacy and safety of the devices during endovascular thrombectomy were analyzed by evaluating the rate of good recanalization after the first pass, clot retrieval rate, final recanalization grade, use of rescue treatment, recanalization time, and hemorrhagic and thromboembolic complications.

Results

Overall, good recanalization (TICI grades 2b and 3) was achieved (Solitaire: n = 57, 72.2%; Trevo: n = 46, 90.2%) (P = 0.01). The rate of good recanalization after the first pass and clot retrieval rate were similar between groups; however, the use of rescue treatment was more frequent in the Solitaire group. Recanalization time was shorter in the Trevo group. The good clinical outcome rate was higher in the Trevo group but not statistically significantly. The rates of symptomatic hemorrhage and thromboembolism were not significantly different between groups.

Conclusion

The Trevo stent achieved more successful recanalization with less need for rescue treatment and less time for recanalization than the Solitaire stent. There was no statistically significant difference in the clinical outcomes.

Mechanical Thrombectomy in Stroke. Experience from Switching from Stent Retriever Only to Stent Retriever Combined with Aspiration Catheter

Endovascular treatment is a rapidly evolving technique; therefore, there is a constant need to evaluate this method and its modifications. This paper discusses a single-center experience and the results of switching from the stent retriever only (SO) mechanical thrombectomy (MT) to the combined approach (CA), with a stent retriever and aspiration catheters.

METHODS

The study involved a retrospective analysis of 70 patients undergoing MT with the use of either SO or CA. The primary endpoint was the frequency of perfect reperfusion defined as grade 3 of the modified Thrombolysis in Cerebral Infarction scale (mTICI) after the first pass. The secondary endpoints were the procedure success, defined as mTICI grades 2b-3; time of the procedure; clinical outcome, measured by 90 days' modified Rankin Scale (mRS) score; Δ NIHSS, defined as the difference between National Institutes of Health Stroke Scale (NIHSS) score at patients' admission and discharge; and the total number of device passes.

RESULTS

Out of the 70 patients included, 33 were treated with SO and 37 with CA. In both groups, a total number of 42 patients received intravenous recombined tissue plasminogen activator (iv-rTPA: 20 patients (60.6%) in the SO group and 22 patients (59.5%) in the CA group (p = 1.000). There was a significant difference between the groups regarding first-pass success rate, with 46% in the CA group and 18% in the SO group, (OR 3.83, 95% CI 1.28 to 11.44, p = 0.016). Complete procedure success tended to be more frequent in the CA group than in the SO group-94.6% vs. 84.8% (OR 3.13, 95% CI 0.56 to 17.34, p = 0.193)-and CA tended to require a lower number of passes than SO (mean 1.76 vs. 2.09 passes per procedure, p = 0.114), yet these differences did not reach statistical significance. Mean duration of the procedure was significantly shorter in the CA group than in the SO group (49 min vs. 64 min, p = 0.017). There was a significant difference in clinical outcomes, with higher Δ NIHSS (9.3 in the CA group vs. 6.7 in the SO group, p = 0.025) after the procedure and 90-day mRS (median 2 in the CA group vs. 4 in the SO group, p = 0.031).

CONCLUSIONS

Combining stent retrievers with aspiration catheters may offer a beneficial effect on angiographic results and clinical outcomes in stroke patients undergoing endovascular treatment.

Mechanical Thrombectomy: Emerging Technologies and Techniques

BACKGROUND

The treatment of acute ischemic stroke due to large vessel occlusion (LVO) has revolutionized in the last decade. We sought to compile the most relevant literature published about the evolution in treating this disabling and fatal disease.

METHODS

A literature review of recent studies describing early treatment options like intravenous tissue plasminogen activator to the latest mechanical thrombectomy (MT) techniques was performed. We described in a chronological order the evolution of LVO treatment.

RESULTS

Recanalization rates with newer techniques and MT devices approach a 90% of effectiveness. Timely interventions have also resulted in better clinical outcomes with approximately 50% of patient achieving functional independence at 90 days. At least 14 new third generation thrombectomy devices are currently being evaluated in in vitro and clinical studies.

CONCLUSIONS

The treatment of LVO with MT is feasible and safe. MT is standard of care in treating acute ischemic stroke due to LVO.

Evolution of endovascular stroke therapies and devices

Acute ischemic stroke is caused by occlusion of a cerebral artery, resulting in loss of brain tissue and neurologic deficits. However, a portion of the ischemic brain can be salvaged if blood flow is restored within an appropriate time frame. The past year has seen the publication of five positive randomized controlled trials demonstrating substantial benefit of mechanical thrombectomy in select patients with large vessel cerebrovascular occlusion. This progress is related to several factors, but most importantly, dramatic improvements in speed and rates of recanalization with the latest generation devices. In this article, we review the evolution of endovascular acute ischemic stroke therapies and key design features of the most widely used devices.