Acute embolic stroke with large-vessel occlusion: does contact aspiration thrombectomy show superiority?

AIM

To compare the efficacy between contact aspiration thrombectomy and stent retriever thrombectomy in the treatment of acute embolic stroke patients with large vessel occlusion.

MATERIALS AND METHODS

Between January 2019 and June 2020, data from consecutive acute ischaemic stroke patients who underwent either endovascular contact aspiration or stent retriever thrombectomy were analysed at one institution. The primary outcome was the full 90-day modified Rankin Scale (mRS) score. Ordinal logistic regression analysis was used to assess the association between thrombectomy approach and functional outcomes.

RESULTS

A total of 156 patients were analysed. Among them, 57 (36.5%) patients underwent primary aspiration thrombectomy, while 99 (63.5%) patients underwent primary stent retriever thrombectomy. The median procedure time was significantly shorter in patients treated with aspiration (37 versus 56 minutes; p<0.001). Compared with those of patients who underwent stent retriever thrombectomy, successful recanalisation rates and favourable functional outcome rates were higher in patients who underwent the aspiration approach (94.7% versus 77.8%, p=0.006; 49.1% versus 27.3%, p=0.006, respectively). Ordinal logistic regression analysis showed that aspiration thrombectomy was independently associated with a good functional outcome (adjusted common odds ratio, 0.30, 95% confidence interval: 0.16-0.60, p<0.001).

CONCLUSION

Among the specific patients with large vessel occlusion in acute embolic stroke, the use of aspiration thrombectomy compared with stent retriever thrombectomy resulted in a greater likelihood of favourable neurological outcomes; however, because of study limitations, these findings should be interpreted as preliminary and require further study to confirm these results.

Non-negligible clinical relevance of haemorrhagic transformation after endovascular thrombectomy with successful reperfusion in acute ischaemic stroke

AIM

To explore the association between haemorrhagic transformation (HT) subtypes and functional outcome in acute ischaemic stroke (AIS) patients with successful recanalization treated by endovascular thrombectomy (EVT).

MATERIALS AND METHODS

Consecutive patients with AIS due to large-vessel occlusion in the anterior circulation, who were treated between January 2015 and June 2019 and achieved successful EVT, were enrolled in this retrospective study. HT was categorized according to the Heidelberg Bleeding Classification. Functional outcome was evaluated using the 90-day modified Rankin Scale (mRS) after stroke onset. Ordinal logistic regression analysis was performed to determine the association of HT subtypes with functional outcomes.

RESULTS

A total of 243 patients were included for further analysis. Among them, 121 (49.8%) had HT. Ten (4.1%) patients were classified as haemorrhagic infarction (HI) subtype 1, 61 (25.1%) as HI subtype 2, 17 (7.0%) as parenchymal haematoma (PH) subtype 1, and 33 (13.6%) as PH subtype 2. Ordinal logistic regression analysis suggested that HI subtype 2 (adjusted common OR 0.357, 95% CI: 0.192-0.667), PH1 (adjusted common OR 0.254, 95% CI: 0.093-0.696) and PH subtype 2 (adjusted common OR 0.017, 95% CI: 0.006-0.051) were significantly associated with poor functional outcomes.

CONCLUSION

The present study shows that HI subtype 2, PH subtype 1, and PH subtype 2 are independently associated with poor clinical outcomes in AIS patients with successful recanalization after EVT.

Risk factors contributing to early and late recurrence of haemoptysis after bronchial artery embolisation

OBJECTIVE

To identify the risk factors for early and late relapse of haemoptysis after bronchial artery embolisation (BAE).

DESIGN

We performed a retrospective study of 255 patients with haemoptysis who underwent BAE from January 2009 to June 2016 at the First Affiliated Hospital of Nanjing Medical University, Nanjing, China. Using a Cox regression model, risk factors contributing to early (within the first month) and late (>1 month) recurrence were analysed. We censored recurrence-free patients at 1 month and patients without rebleeding after 1 month.

RESULTS

The cumulative recurrence rate at 1, 6, 12, 24 and 48 months was respectively 14.9%, 16.9%, 20.6%, 31.0% and 39.9%, with a median follow-up of 574 days. Early relapse occurred in 38 of 255 patients, while late recurrence was found in 45 of the remaining 217 patients. The risk factors related to early recurrence were lung destruction on computed tomography of the chest and involvement of non-bronchial systemic arteries. The risk factors associated with late recurrence were tuberculosis sequelae, the presence of shunts and the use of gelfoam as an embolisation material.

CONCLUSIONS

The variables related to incomplete embolisation were the risk factors for early rebleeding. The variables associated with same-vessel recanalisation and formation of a new collateral circulation influenced late recurrence.

Embolisation for life-threatening haemoptysis complicated by systemic artery-pulmonary circulation shunts

SETTING

Tertiary referral centre.

OBJECTIVE

To retrospectively observe the characteristics of bronchial angiograms in the setting of systemic artery-pulmonary circulation shunts (SPS), and to evaluate the safety and effectiveness of bronchial artery embolisation (BAE) for these patients with life-threatening haemoptysis.

DESIGN

The records of life-threatening haemoptysis patients with SPS who presented to a tertiary referral centre from January 2009 to March 2014 were reviewed.

RESULTS

SPS consisted of bronchial artery-pulmonary artery shunt (AAS) in 30 cases, bronchial artery-pulmonary vein shunt (AVS) in 4 cases, non-bronchial systemic artery-pulmonary circulation shunt (n-BPS) in 7 cases and more than one type of SPS in 4 cases (AAS and AVS in 3 cases, three types of SPS in 1 case). BAE using polyvinyl alcohol (PVA) was successful in 97.8% (44/45) of the patients. Cumulative rates of freedom from recurrence at 1 month, 1 year and 2 years were respectively 97.8%, 93.2% and 85.4%. No major procedure-related complications occurred. No significant differences were found in recurrence rates or cumulative haemoptysis control rates among patients with different types of SPS complications (P = 0.55 and 0.46, respectively).

CONCLUSION

BAE with PVA was safe and effective for life-threatening haemoptysis complicated by SPS.

Use of FLAIR imaging to identify onset time of cerebral ischemia in a canine model

BACKGROUND AND PURPOSE

Stroke is a leading cause of death and disability, and many studies have focused on the evolution of FLAIR imaging in the acute and chronic time window. The purpose of this study was to evaluate the potential efficacy of FLAIR-related techniques in identifying the onset time of cerebral ischemia in a canine embolic stroke model.

MATERIALS AND METHODS

An embolic ischemic model was generated through the use of an autologous clot in 20 beagle dogs. Both FLAIR and DWI were performed at 3 hours, 4 hours, 5 hours, 6 hours, and 24 hours after embolization, respectively. Visual "DWI-FLAIR mismatch" was defined as hyperintense signal detected on DWI but not on FLAIR. The relative signal intensity of FLAIR-positive lesions and the degree of DWI-FLAIR mismatch was calculated as relative FLAIR = relative signal intensity of FLAIR positive lesions, mismatch degree = (100-VFLAIR/VDWI) × 100%.

RESULTS

The ischemic model was successfully established in all animals. FLAIR-positive lesions were seen in 3, 11, 16, 19, and 20 beagle dogs at 5 time points after embolization, respectively. There was significant correlation between the relative FLAIR, degree of DWI-FLAIR mismatch, and the onset time (relative FLAIR: r = +0.42; 95% CI, 0.20-0.60; mismatch degree: r = -0.85; 95% CI, 0.89-0.78). Receiver operating characteristic curves showed that the degree of DWI-FLAIR mismatch could identify the hyperacute ischemic lesions with a sensitivity range from 1.00-0.76; visual DWI-FLAIR mismatch sensitivity ranged from 0.85-0.39, whereas specificity was 0.83-0.95 versus 0.85-1.00.

CONCLUSIONS

The relative FLAIR and DWI-FLAIR mismatch values were useful in predicting the onset time in our canine embolic stroke model. The degree of DWI-FLAIR mismatch proposed in our study could be a good indicator with high sensitivity for identifying the hyperacute ischemic stroke.