Alex Brehm

Dr. Alex Brehm

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2022 in Stroke
Verified
Journal Article
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SYShadi Yaghi
Shadi Yaghi
LSLiqi Shu
Liqi Shu
EBEkaterina Bakradze
Ekaterina Bakradze
SOSetareh Salehi Omran
Setareh Salehi Omran
JGJames Anthony Giles
James Anthony Giles
KFKaren Furie
Karen Furie
Background: A small randomized controlled trial suggested that dabigatran may be as effective as warfarin in the treatment of cerebral venous thrombosis (CVT). We aimed to compare direct oral anticoagulants (DOACs) to warfarin in a real-world CVT cohort. Methods: This multicenter international retrospective study (United States, Europe, New Zealand) included consecutive patients with CVT treated with oral anticoagulation from January 2015 to December 2020. We abstracted demographics and CVT risk factors, hypercoagulable labs, baseline imaging data, and clinical and radiological outcomes from medical records. We used adjusted inverse probability of treatment weighted Cox-regression models to compare recurrent cerebral or systemic venous thrombosis, death, and major hemorrhage in patients treated with warfarin versus DOACs. We performed adjusted inverse probability of treatment weighted logistic regression to compare recanalization rates on follow-up imaging across the 2 treatments groups. Results: Among 1025 CVT patients across 27 centers, 845 patients met our inclusion criteria. Mean age was 44.8 years, 64.7% were women; 33.0% received DOAC only, 51.8% received warfarin only, and 15.1% received both treatments at different times. During a median follow-up of 345 (interquartile range, 140–720) days, there were 5.68 recurrent venous thrombosis, 3.77 major hemorrhages, and 1.84 deaths per 100 patient-years. Among 525 patients who met recanalization analysis inclusion criteria, 36.6% had complete, 48.2% had partial, and 15.2% had no recanalization. When compared with warfarin, DOAC treatment was associated with similar risk of recurrent venous thrombosis (aHR, 0.94 [95% CI, 0.51–1.73]; P =0.84), death (aHR, 0.78 [95% CI, 0.22–2.76]; P =0.70), and rate of partial/complete recanalization (aOR, 0.92 [95% CI, 0.48–1.73]; P =0.79), but a lower risk of major hemorrhage (aHR, 0.35 [95% CI, 0.15–0.82]; P =0.02). Conclusions: In patients with CVT, treatment with DOACs was associated with similar clinical and radiographic outcomes and favorable safety profile when compared with warfarin treatment. Our findings need confirmation by large prospective or randomized studies.

8 June 2021 in Neurology
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Journal Article
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RNRaul G. Nogueira
Raul G. Nogueira
MQMuhammad M. Qureshi
Muhammad M. Qureshi
MAMohamad Abdalkader
Mohamad Abdalkader
SMSheila Ouriques Martins
Sheila Ouriques Martins
HYHiroshi Yamagami
Hiroshi Yamagami
ORon behalf of the SVIN COVID-19 Global Stroke Registry
on behalf of the SVIN COVID-19 Global Stroke Registry
Objective To measure the global impact of COVID-19 pandemic on volumes of IV thrombolysis (IVT), IVT transfers, and stroke hospitalizations over 4 months at the height of the pandemic (March 1 to June 30, 2020) compared with 2 control 4-month periods. Methods We conducted a cross-sectional, observational, retrospective study across 6 continents, 70 countries, and 457 stroke centers. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases. Results There were 91,373 stroke admissions in the 4 months immediately before compared to 80,894 admissions during the pandemic months, representing an 11.5% (95% confidence interval [CI] −11.7 to −11.3, p < 0.0001) decline. There were 13,334 IVT therapies in the 4 months preceding compared to 11,570 procedures during the pandemic, representing a 13.2% (95% CI −13.8 to −12.7, p < 0.0001) drop. Interfacility IVT transfers decreased from 1,337 to 1,178, or an 11.9% decrease (95% CI −13.7 to −10.3, p = 0.001). Recovery of stroke hospitalization volume (9.5%, 95% CI 9.2–9.8, p < 0.0001) was noted over the 2 later (May, June) vs the 2 earlier (March, April) pandemic months. There was a 1.48% stroke rate across 119,967 COVID-19 hospitalizations. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was noted in 3.3% (1,722/52,026) of all stroke admissions. Conclusions The COVID-19 pandemic was associated with a global decline in the volume of stroke hospitalizations, IVT, and interfacility IVT transfers. Primary stroke centers and centers with higher COVID-19 inpatient volumes experienced steeper declines. Recovery of stroke hospitalization was noted in the later pandemic months.

1 March 2022 in Radiology: Artificial Intelligence
Verified
Journal Article
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MSMuhannad Seyam
Muhannad Seyam
TWThomas Weikert
Thomas Weikert
ASAlexander Sauter
Alexander Sauter
ABAlex Brehm
Alex Brehm
MPMarios-Nikos Psychogios
Marios-Nikos Psychogios
KBKristine A. Blackham
Kristine A. Blackham
“Just Accepted” papers have undergone full peer review and have been accepted for publication in Radiology: Artificial Intelligence. This article will undergo copyediting, layout, and proof review ...

11 December 2019 in Journal of Clinical Medicine
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Journal Article
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Marios-Nikos PsychogiosMarios-Nikos Psychogios
Marios-Nikos Psychogios
IMIlko Maier
Ilko Maier
ITIoannis Tsogkas
Ioannis Tsogkas
AHAmélie Carolina Hesse
Amélie Carolina Hesse
ABAlex Brehm
Alex Brehm
JLJan Liman
Jan Liman
Background and purpose: Rapid thrombectomy for acute ischemic stroke caused by large vessel occlusion leads to improved outcome. Optimizing intrahospital management might diminish treatment delays. To examine if one-stop management reduces intrahospital treatment delays and improves functional outcome of acute stroke patients with large vessel occlusion. Methods: We performed a single center, observational study from June 2016 to November 2018. Imaging was acquired with the latest generation angiography suite at a comprehensive stroke center. Two-hundred-thirty consecutive adults with suspected acute stroke presenting within 6 h after symptom onset with a moderate to severe National Institutes of Health Stroke Scale (≥10 in 2016; ≥7 since January 2017) were directly transported to the angiography suite by bypassing multidetector CT. Noncontrast flat-detector CT and biphasic flat-detector CT angiography were acquired with an angiography system. In case of a large vessel occlusion patients remained in the angiography suite, received intravenous rtPA therapy and underwent thrombectomy. As primary endpoints, door-to-reperfusion times and functional outcome at 90 days were recorded and compared in a case-control analysis with matched prior patients receiving standard management. Results: A total of 230 patients (123 women, median age of 78 years (Interquartile Range (IQR) 69–84)) were included. Median symptom-to-door time was 130 min (IQR 70–195). Large vessel occlusion was diagnosed in 166/230 (72%) patients; 64/230 (28%) had conditions not suitable for thrombectomy. Median door-to-reperfusion time for M1 occlusions was 64 min (IQR 56–87). Compared to 43 case-matched patients triaged with multidetector CT, median door-to-reperfusion time was reduced from 102 (IQR 85–117) to 68 min (IQR 53–89; p < 0.001). Rate of good functional outcome was significantly better in the one-stop management group (p = 0.029). Safety parameters (mortality, sICH, any hemorrhage) did not differ significantly between groups. Conclusions: One-stop management for stroke triage reduces intrahospital time delays in our specific hospital setting.

16 July 2023 in Journal of NeuroInterventional Surgery
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Journal Article
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VSVictor Schulze-Zachau
Victor Schulze-Zachau
ABAlex Brehm
Alex Brehm
NNNikolaos Ntoulias
Nikolaos Ntoulias
NKNadja Krug
Nadja Krug
ITIoannis Tsogkas
Ioannis Tsogkas
MPMarios-Nikos Psychogios
Marios-Nikos Psychogios
Background: Vessel perforation during thrombectomy is a severe complication and is hypothesized to be more frequent during medium vessel occlusion (MeVO) thrombectomy. The aim of this study was to compare the incidence and outcome of patients with perforation during MeVO and large vessel occlusion (LVO) thrombectomy and to report on the procedural steps that led to perforation.Methods: In this multicenter retrospective cohort study, data of consecutive patients with vessel perforation during thrombectomy between January 1, 2015 and September 30, 2022 were collected. The primary outcomes were independent functional outcome (ie, modified Rankin Scale 0–2) and all-cause mortality at 90 days. Binomial test, chi-squared test andt-test for unpaired samples were used for statistical analysis.Results: During 25 769 thrombectomies (5124 MeVO, 20 645 LVO) in 25 stroke centers, perforation occurred in 335 patients (1.3%; mean age 72 years, 62% female). Perforation occurred more often in MeVO thrombectomy (2.4%) than in LVO thrombectomy (1.0%,p<0.001). More MeVO than LVO patients with perforation achieved functional independence at 3 months (25.7% vs 10.9%,p=0.001). All-cause mortality did not differ between groups (overall 51.6%). Navigation beyond the occlusion and retraction of stent retriever/aspiration catheter were the two most common procedural steps that led to perforation.Conclusions: In our cohort, perforation was approximately twice as frequent in MeVO than in LVO thrombectomy. Efforts to optimize the procedure may focus on navigation beyond the occlusion site and retraction of stent retriever/aspiration catheter. Further research is necessary in order to identify thrombectomy candidates at high risk of intraprocedural perforation and to provide data on the effectiveness of endovascular countermeasures.

15 April 2019 in BMC Neurology
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Journal Article
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ABAlex Brehm
Alex Brehm
VMVolker Maus
Volker Maus
ITIoannis Tsogkas
Ioannis Tsogkas
RCRuben Colla
Ruben Colla
AHAmélie Carolina Hesse
Amélie Carolina Hesse
Marios-Nikos PsychogiosMarios-Nikos Psychogios
Marios-Nikos Psychogios
Embolectomy is the standard of care in acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). Aim of this study was to compare two techniques: A Direct Aspiration First Pass Technique (ADAPT) and Stent-retriever Assisted Vacuum-locked Extraction (SAVE) stratified by the occluded vessel. One hundred seventy-one patients (71 male) treated between January 2014 and September 2017 with AIS due to LVO of the anterior circulation (55 carotid T, 94 M1, 22 M2) were included. Treatment techniques were divided into two categories: ADAPT and SAVE. Primary endpoints were successful reperfusion (mTICI ≥2b), near-perfect reperfusion (mTICI ≥2c) and groin puncture to reperfusion time. Secondary endpoints were the number of device-passes, first-pass reperfusion, the frequency of emboli to new territory (ENT), clinical outcome at 90 days, and the frequency of symptomatic intracranial hemorrhage (sICH). Analysis was performed on an intention to treat basis. Overall, SAVE resulted in significant higher rates of successful reperfusion (mTICI≥2b) compared to ADAPT (93.5% vs 75.0%; p = 0.006). After stratification for the occluded vessel only the carotid T remained significant with higher rates of near-perfect reperfusion (mTICI≥2c) (55.2% vs 15.4%; p = 0.025), while for successful reperfusion a trend remained (93.1% vs 65.4%; p = 0.10). Groin to reperfusion times were not significantly different. Secondary analysis revealed higher rates of first-pass successful reperfusion (59.6% vs 33.3%; p = 0.019), higher rates of first-pass near-perfect reperfusion in the carotid T (35.4% vs 16.7%; p = 0.038) and a lower number of device-passes overall (median 1 IQR 1–2 vs 2 IQR 2–3; p < 0.001) and in the carotid T (median 2 IQR 1.3 vs 3 IQR 2–5; p < 0.001) for SAVE. Clinical outcome and safety parameters were comparable between groups. Embolectomy using SAVE appears superior to ADAPT, especially for carotid T occlusions with regard to reperfusion success.