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Matthew E. Eagles, Michael K. Tso and R. Loch Macdonald

OBJECTIVE

Fluctuations in patient serum sodium levels are common after aneurysmal subarachnoid hemorrhage (aSAH), but their effect on patient outcome is not well described in the literature. The goal of this work was to better characterize the relationship between fluctuations in serum sodium levels, outcome, and the development of delayed cerebral ischemia (DCI) after aSAH.

METHODS

The authors performed a post hoc analysis of data from the Clazosentan to Overcome Neurological Ischemia and Infarction Occurring After Subarachnoid Hemorrhage (CONSCIOUS-1) trial. Patients had their serum sodium values recorded daily for 14 days post-aSAH. Average and average absolute daily differences in sodium levels were calculated for each patient based on 3 reference points: admission sodium levels, a normal sodium level (defined as 140 mmol/L), and the previous day’s sodium level. These variables were also calculated for the classic “vasospasm window” (days 3–12) post-aSAH. A stepwise logistic regression model, locally weighted scatterplot smoothing curves, and receiver operator characteristic curve analysis were used to evaluate the relationship between alterations in serum sodium levels and clinical outcome or the development of DCI after aSAH. Poor outcome was defined as a modified Rankin Scale (mRS) score of > 2 at 3 months.

RESULTS

The average daily difference in sodium values from baseline (p < 0.001), average daily difference from a normal sodium level (p < 0.001), average absolute daily difference from a normal sodium level (p = 0.015), and average absolute daily difference from the previous day’s sodium level (p = 0.017) were significant predictors of poor outcome in a stepwise multivariate regression model. There was a trend toward significance for average absolute daily difference from admission sodium levels during the vasospasm window as an independent predictor of DCI (p = 0.052). There was no difference in the predictive capacity for DCI when sodium fluctuations from post-aSAH days 1–14 were compared with those from the classic vasospasm window (days 3–12).

CONCLUSIONS

Fluctuations in serum sodium levels may play a role in clinical outcome and the development of DCI after aSAH. The timing of these fluctuations appears to have no significant effect on the development of DCI.

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Aaron Hockley, Michael K. Tso, Mohammed A. Almekhlafi, Abhay K. Lodha, Robin Clegg, Jeremy Luntley, Muneer Eesa and John H. Wong

OBJECTIVE

Vein of Galen aneurysmal malformations (VGAMs) in infancy have a poor natural history if left untreated. Their high-flow nature can preclude safe and accurate therapeutic vessel occlusion and the risk of inadvertent pulmonary embolism is predominant. The authors describe the technique of rapid cardiac ventricular pacing for inducing transient hypotension to facilitate the controlled embolization of VGAMs.

METHODS

Initial transjugular venous access was obtained for placing temporary pacing leads for rapid cardiac ventricular pacing immediately prior to embolization. Definitive transarterial embolization procedures for the VGAMs were then performed in the same setting in which liquid embolic agents or coils were used.

RESULTS

Beginning in 2010, a total of five procedures were performed in three infants. Transvenous rapid cardiac ventricular pacing was successfully achieved to induce systemic transient flow arrest in all but two attempts, and facilitated partial embolization with n-butyl cyanoacrylate (n-BCA) and coils in all procedures. Ventricular fibrillation occurred twice in one patient and was successfully reversed with defibrillation on both occasions. One patient failed to improve and died from refractory heart failure. Two patients stabilized following staged embolization.

CONCLUSIONS

Rapid transvenous cardiac ventricular pacing can be considered to induce transient hypotension and facilitate controlled embolization in challenging high-flow VGAMs.

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Kunal Vakharia, Stephan A. Munich, Michael K. Tso, Muhammad Waqas and Elad I. Levy

Stent-assisted coiling offers a potential solution for coil embolization of broad-based aneurysms. Challenges associated with navigating a microcatheter beyond these aneurysms sometimes require looping the microcatheter within the aneurysm dome. Reducing microcatheter loops within domes can be difficult, and anchor techniques have been described, including balloon anchor, stent-retriever anchor, and stent anchor techniques. The authors present a patient requiring stent-assisted coiling of an anterior communicating artery aneurysm in whom a stent anchor technique was used to reduce a microcatheter loop within an aneurysm dome before coil embolization. Postembolization angiographic runs showed complete coil occlusion of the aneurysm with approximately 35% packing density.

The video can be found here: https://youtu.be/zHR1ZOArUro.

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Michael K. Tso, Myunghyun M. Lee, Chad G. Ball, William F. Morrish, Alim P. Mitha, Andrew W. Kirkpatrick and John H. Wong

OBJECTIVE

Blunt cerebrovascular injury (BCVI) occurs in approximately 1% of the blunt trauma population and may lead to stroke and death. Early vascular imaging in asymptomatic patients at high risk of having BCVI may lead to earlier diagnosis and possible stroke prevention. The objective of this study was to determine if the implementation of a formalized asymptomatic BCVI screening protocol with CT angiography (CTA) would lead to improved BCVI detection and stroke prevention.

METHODS

Patients with vascular imaging studies were identified from a prospective trauma registry at a single Level 1 trauma center between 2002 and 2008. Detection of BCVI and stroke rates were compared during the 3-year periods before and after implementation of a consensus-based asymptomatic BCVI screening protocol using CTA in 2005.

RESULTS

A total of 5480 patients with trauma were identified. The overall BCVI detection rate remained unchanged postprotocol compared with preprotocol (0.8% [24 of 3049 patients] vs 0.9% [23 of 2431 patients]; p = 0.53). However, postprotocol there was a trend toward a decreased risk of stroke secondary to BCVI on a trauma population basis (0.23% [7 of 3049 patients] vs 0.53% [13 of 2431 patients]; p = 0.06). Overall, 75% (35 of 47) of patients with BCVI were treated with antiplatelet agents, but no patient developed new or progressive intracranial hemorrhage despite 70% of these patients having concomitant traumatic brain injury.

CONCLUSIONS

The results of this study suggest that a CTA screening protocol for BCVI may be of clinical benefit with possible reduction in ischemic complications. The treatment of BCVI with antiplatelet agents appears to be safe.

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Aaron Hockley, Michael K. Tso, Mohammed A. Almekhlafi, Abhay K. Lodha, Robin Clegg, Jeremy Luntley, Muneer Eesa and John H. Wong

OBJECTIVE

Vein of Galen aneurysmal malformations (VGAMs) in infancy have a poor natural history if left untreated. Their high-flow nature can preclude safe and accurate therapeutic vessel occlusion and the risk of inadvertent pulmonary embolism is predominant. The authors describe the technique of rapid cardiac ventricular pacing for inducing transient hypotension to facilitate the controlled embolization of VGAMs.

METHODS

Initial transjugular venous access was obtained for placing temporary pacing leads for rapid cardiac ventricular pacing immediately prior to embolization. Definitive transarterial embolization procedures for the VGAMs were then performed in the same setting in which liquid embolic agents or coils were used.

RESULTS

Beginning in 2010, a total of five procedures were performed in three infants. Transvenous rapid cardiac ventricular pacing was successfully achieved to induce systemic transient flow arrest in all but two attempts, and facilitated partial embolization with n-butyl cyanoacrylate (n-BCA) and coils in all procedures. Ventricular fibrillation occurred twice in one patient and was successfully reversed with defibrillation on both occasions. One patient failed to improve and died from refractory heart failure. Two patients stabilized following staged embolization.

CONCLUSIONS

Rapid transvenous cardiac ventricular pacing can be considered to induce transient hypotension and facilitate controlled embolization in challenging high-flow VGAMs.

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Xiao Wu, David Durand, Vivek B. Kalra, Renu Liu and Ajay Malhotra