Contact aspiration and stent retriever versus stent retriever alone following mechanical thrombectomy for patients of acute ischemic stroke: A recanalization success analysis

OBJECTIVE

Second-generation catheters used in mechanical thrombectomy have different advantages and disadvantages. The objective of this study was to evaluate the effectiveness and safety of the combination of contact aspiration and stent retriever technique on the rate of reperfusion after mechanical thrombectomy for large vessel occlusion.

METHODS

Patients who underwent contact aspiration alone (CAA cohort, n = 150), stent retriever alone (SRA cohort, n = 129), or combined contact aspiration and stent retriever (CSR cohort, n = 122) techniques following mechanical thrombectomy were included in the analysis. A balloon guide catheter was used for all thrombectomies. Digital subtraction angiography was used to identify thrombolysis in cerebral infarction.

RESULTS

The number of patients with thrombolysis in cerebral infarction score of ≥ 2c (near complete or complete antegrade reperfusion) was significantly higher in the CSR cohort than those in the CAA cohort (101 [83%] vs. 90 [60%], p < 0.0001) and those of SRA cohort (101 [83%] vs. 77 [59%], p = 0.0001). Arterial perforation was higher in patients in the CSR cohort than in those in the CAA (p < 0.0001) and SRA (p = 0.015) cohorts. Intracerebral hemorrhage was lower in patients in the CSR cohort than in those in the CAA (p = 0.0001) and SRA (p = 0.0353) cohorts. All-cause mortality at 1 year was fewer in the CSR cohort than in the CAA cohort (p = 0.018).

CONCLUSIONS

The combination of thrombo aspiration by large bore aspiration catheter and stent retriever is the most effective technique but has some related risks.

LEVEL OF EVIDENCE

IV.

TECHNICAL EFFICACY STAGE

1.

2b Or 2c-3? A meta-analysis of first pass thrombolysis in cerebral infarction 2b vs multiple pass thrombolysis in cerebral infarction 2c-3 following mechanical thrombectomy for stroke

BACKGROUND

Procedural success following mechanical thrombectomy for acute ischemic stroke is assessed using the thrombolysis in cerebral infarction scale. We conducted a systematic review and meta-analysis to determine whether outcomes differed between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3.

METHODS

We conducted a systematic review of the literature using PubMed, Embase, Scopus, and Web of Science. We included original studies in which outcomes were stratified based on first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. The primary outcome of interest was the rate of modified Rankin Scale 0-2. Secondary outcomes of interest were rates of modified Rankin Scale 0-1, symptomatic intracranial hemorrhage, and mortality. We calculated odds ratios and corresponding 95% confidence intervals.

RESULTS

Four studies with 1554 patients were included in the quantitative analysis. Rate of modified Rankin Scale 0-2 (odds ratio = 0.91, 95% confidence interval = 0.70-1.18; P-value = 0.49), modified Rankin Scale 0-1 (odds ratio = 1.21, 95% confidence interval = 0.86-1.71; P-value = 0.27), symptomatic intracranial hemorrhage (odds ratio = 1.36, 95% confidence interval = 0.47-3.98; P-value = 0.57), and mortality (odds ratio = 0.91, 95% confidence interval = 0.67-1.25; P-value = 0.56) did not differ between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. There was no heterogeneity among included studies for modified Rankin Scale 0-2, modified Rankin Scale 0-1, or mortality; however, there was moderate heterogeneity among studies for symptomatic intracranial hemorrhage (I2 = 53%, P-value = 0.12).

CONCLUSIONS

Clinical and safety outcomes did not differ between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. Future prospective studies and clinical trials should determine whether first pass thrombolysis in cerebral infarction 2b is a viable endpoint to thrombolysis in cerebral infarction 2c-3.

Use of patient specific 3D printed neurovascular phantoms to simulate mechanical thrombectomy

BACKGROUND

The ability of the patient specific 3D printed neurovascular phantoms to accurately replicate the anatomy and hemodynamics of the chronic neurovascular diseases has been demonstrated by many studies. Acute occurrences, however, may still require further development and investigation and therefore we studied acute ischemic stroke (AIS). The efficacy of endovascular procedures such as mechanical thrombectomy (MT) for the treatment of large vessel occlusion (LVO), can be improved by testing the performance of thrombectomy devices and techniques using patient specific 3D printed neurovascular models.

METHODS

3D printed phantoms were connected to a flow loop with physiologically relevant flow conditions, including input flow rate and fluid temperature. A simulated blood clot was introduced into the model and placed in the proximal Middle Cerebral Artery (MCA) region. Clot location, composition, length, and arterial angulation were varied and MTs were simulated using stent retrievers. Device placement relative to the clot and the outcome of the thrombectomy were recorded for each situation. Digital subtraction angiograms (DSA) were captured before and after LVO simulation. Recanalization outcome was evaluated using DSA as either 'no recanalization' or 'recanalization'. Forty-two 3DP neurovascular phantom benchtop experiments were performed.

RESULTS

Clot angulation within the MCA region had the most significant impact on the MT outcome, with a p-value of 0.016. Other factors such as clot location, clot composition, and clot length correlated weakly with the MT outcome.

CONCLUSIONS

This project allowed us to gain knowledge of how such characteristics influence thrombectomy success and can be used in making clinical decisions when planning the procedure and selecting specific thrombectomy tools and approaches.

Mechanical Thrombectomy in Embolic Cardiac Myxoma: Case Report and Literature Review

Myxomas are the most common cardiac tumors and present clinically with cardiac manifestations, systemic constitutional symptoms, and embolic events. Posterior circulation involvement occurs in approximately 20 percent of cerebral ischemic events.The endovascular technique is an established life-saving therapy for eligible patients upto 24 hours from symptom onset. However, the role of endovascular management in embolic atrial myxoma remains unknown with no international consensus guidelines for the management of stroke in such patient population. Here, we present a case report of an embolic posterior circulation stroke in a young female treated with mechanical thrombectomy at 23 hours from symptom onset. To the best of our knowledge, this is the first thrombectomy case in posterior circulation with embolism from myxoma. Further workup confirmed an atrial myxoma which was resected. We also review the previous cases with mechanical thrombectomy done in such cases.

Diminishing returns with successive device passes in mechanical thrombectomy for stroke

BACKGROUND

Multiple device passes are associated with complications and poor functional outcomes following mechanical thrombectomy (MT) for emergent large vessel occlusion (ELVO).

OBJECTIVE

To characterize the relationship between number of device passes, complications, angiographic outcomes, and clinical outcomes in MT for ELVO.

METHODS

This is a single-center, retrospective cohort study. Individual device passes for MT were evaluated for any change in Thrombolysis in Cerebral Infarction (TICI) score, successful revascularization (TICI 2b or 3), and complications. Outcomes were compared among groups requiring multiple passes with various cut-off points. Risk factors for unfavorable clinical outcome [90 day modified Rankin Scale > 2] were assessed using multivariate analysis.

RESULTS

Successful revascularization was achieved in 75% of 163 patients and 36% required only one device pass. After the second pass, the likelihood of angiographic improvement significantly decreased (p < 0.001). Using multiple cut-off points, higher post-procedural NIHSS scores, mortality rates, and unfavorable 90-day outcomes were associated with a greater number of passes. Multivariate analysis revealed ICA thrombus (comparison: M2, OR: 25, 95% CI 2-275, p = 0.01) and failed revascularization (OR: 68, 95% CI 3.12-1489, p = 0.01) as the only significant predictors of unfavorable clinical outcome. Nonetheless, the likelihood of favorable clinical outcome was higher in patients with an ICA occlusion who were revascularized in < 2 vs. ≥ 2 (44 vs 4%, p = 0.01) or < 3 vs. ≥ 3 (32 vs. 0%, p = 0.02) passes.

CONCLUSION

The likelihood of angiographic improvement in patients with ELVO significantly decreases after the second pass. A greater number of passes is associated with worsened clinical outcomes.