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Dive into the research topics where Christopher Traenka is active.

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Featured researches published by Christopher Traenka.


Circulation | 2015

Recanalization therapies in acute ischemic stroke patients: impact of prior treatment with novel oral anticoagulants on bleeding complications and outcome

David J. Seiffge; Robbert-JanVan Hooff; Christian H. Nolte; Yannick Béjot; Guillaume Turc; Benno Ikenberg; Eivind Berge; Malte Persike; Nelly Dequatre-Ponchelle; Daniel Strbian; Waltraud Pfeilschifter; Andrea Zini; Arnstein Tveiten; Halvor Naess; Patrik Michel; Roman Sztajzel; Andreas R. Luft; Henrik Gensicke; Christopher Traenka; Lisa Hert; Jan F. Scheitz; Gian Marco De Marchis; Leo H. Bonati; Nils Peters; Andreas Charidimou; David J. Werring; Frederick Palm; Matthias Reinhard; Wolf-Dirk Niesen; Takehiko Nagao

Background— We explored the safety of intravenous thrombolysis (IVT) or intra-arterial treatment (IAT) in patients with ischemic stroke on non-vitamin K antagonist oral anticoagulants (NOACs, last intake <48 hours) in comparison with patients (1) taking vitamin K antagonists (VKAs) or (2) without previous anticoagulation (no-OAC). Methods and Results— This is a multicenter cohort pilot study. Primary outcome measures were (1) occurrence of intracranial hemorrhage (ICH) in 3 categories: any ICH (ICHany), symptomatic ICH according to the criteria of the European Cooperative Acute Stroke Study II (ECASS-II) (sICHECASS-II) and the National Institute of Neurological Disorders and Stroke (NINDS) thrombolysis trial (sICHNINDS); and (2) death (at 3 months). Cohorts were compared by using propensity score matching. Our NOAC cohort comprised 78 patients treated with IVT/IAT and the comparison groups of 441 VKA patients and 8938 no-OAC patients. The median time from last NOAC intake to IVT/IAT was 13 hours (interquartile range, 8–22 hours). In VKA patients, median pre-IVT/IAT international normalized ratio was 1.3 (interquartile range, 1.1–1.6). ICHany was observed in 18.4% NOAC patients versus 26.8% in VKA patients and 17.4% in no-OAC patients. sICHECASS-II and sICHNINDS occurred in 2.6%/3.9% NOAC patients, in comparison with 6.5%/9.3% of VKA patients and 5.0%/7.2% of no-OAC patients, respectively. At 3 months, 23.0% of NOAC patients in comparison with 26.9% of VKA patients and 13.9% of no-OAC patients had died. Propensity score matching revealed no statistically significant differences. Conclusions— IVT/IAT in selected patients with ischemic stroke under NOAC treatment has a safety profile similar to both IVT/IAT in patients on subtherapeutic VKA treatment or in those without previous anticoagulation. However, further prospective studies are needed, including the impact of specific coagulation tests.


Circulation | 2015

Recanalization Therapies in Acute Ischemic Stroke Patients: Impact of Prior Treatment with Novel Oral Anticoagulants on Bleeding Complications and Outcome - A Pilot Study

David J. Seiffge; Robbert-Jan Van Hooff; Christian H. Nolte; Yannick Béjot; Guillaume Turc; Benno Ikenberg; Eivind Berge; Malte Persike; Nelly Dequatre-Ponchelle; Daniel Strbian; Waltraud Pfeilschifter; Andrea Zini; Arnstein Tveiten; Halvor Naess; Patrik Michel; Roman Sztajzel; Andreas R. Luft; Henrik Gensicke; Christopher Traenka; Lisa Hert; Jan F. Scheitz; GianMarco De Marchis; Leo H. Bonati; Nils Peters; Andreas Charidimou; David J. Werring; Frederick Palm; Matthias Reinhard; Wolf-Dirk Niesen; Takehiko Nagao

Background— We explored the safety of intravenous thrombolysis (IVT) or intra-arterial treatment (IAT) in patients with ischemic stroke on non-vitamin K antagonist oral anticoagulants (NOACs, last intake <48 hours) in comparison with patients (1) taking vitamin K antagonists (VKAs) or (2) without previous anticoagulation (no-OAC). Methods and Results— This is a multicenter cohort pilot study. Primary outcome measures were (1) occurrence of intracranial hemorrhage (ICH) in 3 categories: any ICH (ICHany), symptomatic ICH according to the criteria of the European Cooperative Acute Stroke Study II (ECASS-II) (sICHECASS-II) and the National Institute of Neurological Disorders and Stroke (NINDS) thrombolysis trial (sICHNINDS); and (2) death (at 3 months). Cohorts were compared by using propensity score matching. Our NOAC cohort comprised 78 patients treated with IVT/IAT and the comparison groups of 441 VKA patients and 8938 no-OAC patients. The median time from last NOAC intake to IVT/IAT was 13 hours (interquartile range, 8–22 hours). In VKA patients, median pre-IVT/IAT international normalized ratio was 1.3 (interquartile range, 1.1–1.6). ICHany was observed in 18.4% NOAC patients versus 26.8% in VKA patients and 17.4% in no-OAC patients. sICHECASS-II and sICHNINDS occurred in 2.6%/3.9% NOAC patients, in comparison with 6.5%/9.3% of VKA patients and 5.0%/7.2% of no-OAC patients, respectively. At 3 months, 23.0% of NOAC patients in comparison with 26.9% of VKA patients and 13.9% of no-OAC patients had died. Propensity score matching revealed no statistically significant differences. Conclusions— IVT/IAT in selected patients with ischemic stroke under NOAC treatment has a safety profile similar to both IVT/IAT in patients on subtherapeutic VKA treatment or in those without previous anticoagulation. However, further prospective studies are needed, including the impact of specific coagulation tests.


Neurology | 2016

Early start of DOAC after ischemic stroke: Risk of intracranial hemorrhage and recurrent events

David J. Seiffge; Christopher Traenka; Alexandros Polymeris; Lisa Hert; Nils Peters; Philippe Lyrer; Stefan T. Engelter; Leo H. Bonati; Gian Marco De Marchis

Objective: In patients with recent acute ischemic stroke (AIS) and atrial fibrillation, we assessed the starting time of direct, non–vitamin K antagonist oral anticoagulants (DOACs) for secondary prevention, the rate of intracranial hemorrhage (ICH), and recurrent ischemic events during follow-up. Methods: We included consecutive patients with nonvalvular atrial fibrillation admitted to our hospital for AIS or TIA (index event) who received secondary prophylaxis with DOAC or vitamin K antagonists (VKAs). Follow-up was at least 3 months. In the primary analysis, we compared rates of ICH and recurrent ischemic events (AIS or TIA) between patients with early (≤7 days since event; DOACearly) and those with late (>7 days, DOAClate) start of DOAC. Results: Two hundred four patients were included (median age 79 years, 89% AIS) and total follow-up time was 78.25 patient-years. One hundred fifty-five patients received DOAC with a median delay of 5 days after the index event (interquartile range 3–11) and 49 received VKA. DOAC was started early in 100 patients (65%). We observed one ICH (1.3%/y) and 6 recurrent AIS (7.7%/y). The ICH occurred in a patient taking VKA. No significant difference in the rate of recurrent AIS between DOACearly (5.1%/y) and DOAClate (9.3%/y, p = 0.53) was observed. Conclusions: Even if DOACs are often started early after an index event, the risk of ICH appears to be low. Among all patients receiving anticoagulation, the rate of recurrent events was 6 times higher than the rate of ICH.


Journal of Neurology | 2015

Risk factors, aetiology and outcome of ischaemic stroke in young adults: the Swiss Young Stroke Study (SYSS).

Barbara Goeggel Simonetti; Marie-Luise Mono; Uyen Huynh-Do; Patrik Michel; Céline Odier; Roman Sztajzel; Philippe Lyrer; Stefan T. Engelter; Leo H. Bonati; Henrik Gensicke; Christopher Traenka; Barbara Tettenborn; Bruno Weder; Urs Fischer; Aekaterini Galimanis; Simon Jung; Rudolf Luedi; Gian Marco De Marchis; Anja Weck; Carlo Cereda; Ralf W. Baumgartner; Claudio L. Bassetti; Heinrich P. Mattle; Krassen Nedeltchev; Marcel Arnold

Barbara Goeggel Simonetti • Marie-Luise Mono • Uyen Huynh-Do • Patrik Michel • Celine Odier • Roman Sztajzel • Philippe Lyrer • Stefan T. Engelter • Leo Bonati • Henrik Gensicke • Christopher Traenka • Barbara Tettenborn • Bruno Weder • Urs Fischer • Aekaterini Galimanis • Simon Jung • Rudolf Luedi • Gian Marco De Marchis • Anja Weck • Carlo W. Cereda • Ralf Baumgartner • Claudio L. Bassetti • Heinrich P. Mattle • Krassen Nedeltchev • Marcel Arnold


Neurologic Clinics | 2015

Diagnosis and Treatment of Cervical Artery Dissection

Stefan T. Engelter; Christopher Traenka; Alexander von Hessling; Philippe Lyrer

Cervical artery dissection (CAD) is a major cause of stroke in the young. A mural hematoma is detected in most CAD patients. The intramural blood accumulation should not be considered a reason to withhold intravenous thrombolysis in patients with CAD-related stroke. Because intravenous-thrombolyzed CAD patients might not recover as well as other stroke patients, acute endovascular treatment is an alternative. Regarding the choice of antithrombotic agents, this article discusses the findings of 4 meta-analyses across observational data, the current status of 3 randomized controlled trials, and arguments and counterarguments favoring anticoagulants over antiplatelets. Furthermore, the role of stenting and surgery is addressed.


European Journal of Neurology | 2014

Intravenous thrombolysis in stroke patients receiving rivaroxaban.

David J. Seiffge; Christopher Traenka; Henrik Gensicke; D. A. Tsakiris; Leo H. Bonati; Nils Peters; P. A. Lyrer; S. T. Engelter

New oral anticoagulants (NOACs) including dabigatran and rivaroxaban are approved for prevention of stroke in patients with atrial fibrillation (AF) [1]. To date, existing NOAC treatment is considered a contraindication for intravenous thrombolysis (IVT) in the case of acute stroke [2]. Nevertheless, rational approaches for the use of IVT in patients taking dabigatran have been published [3]. IVT under dabigatran treatment has been reported [4–6] but no data are available on rivaroxaban. Based on theoretical considerations, recent recommendations suggest that IVT might be considered in the case of low plasma levels of rivaroxaban [7]. We report on such cases. Case A


Stroke | 2017

Sex Differences and Functional Outcome After Intravenous Thrombolysis

Fianne H. Spaander; Sanne M. Zinkstok; Irem M. Baharoglu; Henrik Gensicke; Alexandros Polymeris; Christopher Traenka; Christian Hametner; Peter A. Ringleb; Sami Curtze; Nicolas Martinez-Majander; Karoliina Aarnio; Christian H. Nolte; Jan F. Scheitz; Didier Leys; Anais Hochart; Visnja Padjen; Georg Kägi; Alessandro Pezzini; Patrik Michel; Olivier Bill; Andrea Zini; Stefan T. Engelter; Paul J. Nederkoorn

Background and Purpose— Women have a worse outcome after stroke compared with men, although in intravenous thrombolysis (IVT)–treated patients, women seem to benefit more. Besides sex differences, age has also a possible effect on functional outcome. The interaction of sex on the functional outcome in IVT-treated patients in relation to age remains complex. The purpose of this study was to compare outcome after IVT between women and men with regard to age in a large multicenter European cohort reflecting daily clinical practice of acute stroke care. Methods— Data were obtained from IVT registries of 12 European tertiary hospitals. The primary outcome was poor functional outcome, defined as a modified Rankin scale score of 3 to 6 at 3 months. We stratified outcome by age in decades. Safety measures were symptomatic intracranial hemorrhage and mortality at 3 months. Results— In this cohort, 9495 patients were treated with IVT, and 4170 (43.9%) were women with a mean age of 71.9 years. After adjustments for baseline differences, female sex remained associated with poor functional outcome (odds ratio, 1.15; 95% confidence interval, 1.02–1.31). There was no association between sex and functional outcome when data were stratified by age. Symptomatic intracranial hemorrhage rate was similar in both sexes (adjusted odds ratio, 0.93; 95% confidence interval, 0.73–1.19), whereas mortality was lower among women (adjusted odds ratio, 0.83; 95% confidence interval, 0.70–0.99). Conclusions— In this large cohort of IVT-treated patients, women more often had poor functional outcome compared with men. This difference was not dependent on age.


Journal of stroke | 2017

Intravenous Thrombolysis in Patients with Stroke Taking Rivaroxaban Using Drug Specific Plasma Levels: Experience with a Standard Operation Procedure in Clinical Practice

David J. Seiffge; Christopher Traenka; Alexandros Polymeris; Sebastian Thilemann; Benjamin Wagner; Lisa Hert; Mandy D. Müller; Henrik Gensicke; Nils Peters; Christian H. Nickel; Christoph Stippich; Raoul Sutter; Stephan Marsch; Urs Fisch; Raphael Guzman; Gian Marco De Marchis; Philippe Lyrer; Leo H. Bonati; Dimitrios Tsakiris; Stefan T. Engelter

Background and Purpose Standard operating procedures (SOP) incorporating plasma levels of rivaroxaban might be helpful in selecting patients with acute ischemic stroke taking rivaroxaban suitable for IVthrombolysis (IVT) or endovascular treatment (EVT). Methods This was a single-center explorative analysis using data from the Novel-Oral-Anticoagulants-in-Stroke-Patients-registry (clinicaltrials.gov:NCT02353585) including acute stroke patients taking rivaroxaban (September 2012 to November 2016). The SOP included recommendation, consideration, and avoidance of IVT if rivaroxaban plasma levels were <20 ng/mL, 20‒100 ng/mL, and >100 ng/mL, respectively, measured with a calibrated anti-factor Xa assay. Patients with intracranial artery occlusion were recommended IVT+EVT or EVT alone if plasma levels were ≤100 ng/mL or >100 ng/mL, respectively. We evaluated the frequency of IVT/EVT, door-to-needle-time (DNT), and symptomatic intracranial or major extracranial hemorrhage. Results Among 114 acute stroke patients taking rivaroxaban, 68 were otherwise eligible for IVT/EVT of whom 63 had plasma levels measured (median age 81 years, median baseline National Institutes of Health Stroke Scale 6). Median rivaroxaban plasma level was 96 ng/mL (inter quartile range [IQR] 18‒259 ng/mL) and time since last intake 11 hours (IQR 4.5‒18.5 hours). Twenty-two patients (35%) received IVT/EVT (IVT n=15, IVT+EVT n=3, EVT n=4) based on SOP. Median DNT was 37 (IQR 30‒60) minutes. None of the 31 patients with plasma levels >100 ng/mL received IVT. Among 14 patients with plasma levels ≤100 ng/mL, the main reason to withhold IVT was minor stroke (n=10). No symptomatic intracranial or major extracranial bleeding occurred after treatment. Conclusions Determination of rivaroxaban plasma levels enabled IVT or EVT in one-third of patients taking rivaroxaban who would otherwise be ineligible for acute treatment. The absence of major bleeding in our pilot series justifies future studies of this approach.


Current Genomics | 2017

Genetic Imbalance in Patients with Cervical Artery Dissection

Caspar Grond-Ginsbach; Bowang Chen; Michael Krawczak; Rastislav Pjontek; Philip Ginsbach; Yanxiang Jiang; Shérine Abboud; Marie-Luise Arnold; Anna Bersano; Tobias Brandt; Valeria Caso; Stéphanie Debette; Martin Dichgans; Andreas Geschwendtner; Giacomo Giacalone; Juan-Jose Martin; Antti J. Metso; Tiina M. Metso; Armin J. Grau; Manja Kloss; Christoph Lichy; Alessandro Pezzini; Christopher Traenka; Stefan Schreiber; Vincent Thijs; Emmanuel Touzé; Elisabetta Del Zotto; Turgut Tatlisumak; Didier Leys; Philippe Lyrer

Background: Genetic and environmental risk factors are assumed to contribute to the susceptibility to cervical artery dissection (CeAD). To explore the role of genetic imbalance in the etiology of CeAD, copy number variants (CNVs) were identified in high-density microarrays samples from the multicenter CADISP (Cervical Artery Dissection and Ischemic Stroke Patients) study and from control subjects from the CADISP study and the German PopGen biobank. Microarray data from 833 CeAD patients and 2040 control subjects (565 subjects with ischemic stroke due to causes different from CeAD and 1475 disease-free individuals) were analyzed. Rare genic CNVs were equally frequent in CeAD-patients (16.4%; n=137) and in control subjects (17.0%; n=346) but differed with respect to their genetic content. Compared to control subjects, CNVs from CeAD patients were enriched for genes associated with muscle organ development and cell differentiation, which suggests a possible association with arterial development. CNVs affecting cardiovascular system development were more common in CeAD patients than in control subjects (p=0.003; odds ratio (OR) =2.5; 95% confidence interval (95% CI) =1.4-4.5) and more common in patients with a familial history of CeAD than in those with sporadic CeAD (p=0.036; OR=11.2; 95% CI=1.2-107). Conclusion: The findings suggest that rare genetic imbalance affecting cardiovascular system development may contribute to the risk of CeAD. Validation of these findings in independent study populations is warranted.


Thrombosis and Haemostasis | 2015

ASTRAL-R score predicts non-recanalisation after intravenous thrombolysis in acute ischaemic stroke

Peter Vanacker; Mirjam Rachel Heldner; David J. Seiffge; Hubertus Mueller; Ashraf Eskandari; Christopher Traenka; George Ntaios; Pascal J. Mosimann; Roman Sztajzel; V. Mendes Pereira; Patrick Cras; S. T. Engelter; P. A. Lyrer; Urs Fischer; Dimitris Lambrou; Marcel Arnold; Patrik Michel

Intravenous thrombolysis (IVT) as treatment in acute ischaemic strokes may be insufficient to achieve recanalisation in certain patients. Predicting probability of non-recanalisation after IVT may have the potential to influence patient selection to more aggressive management strategies. We aimed at deriving and internally validating a predictive score for post-thrombolytic non-recanalisation, using clinical and radiological variables. In thrombolysis registries from four Swiss academic stroke centres (Lausanne, Bern, Basel and Geneva), patients were selected with large arterial occlusion on acute imaging and with repeated arterial assessment at 24 hours. Based on a logistic regression analysis, an integer-based score for each covariate of the fitted multivariate model was generated. Performance of integer-based predictive model was assessed by bootstrapping available data and cross validation (delete-d method). In 599 thrombolysed strokes, five variables were identified as independent predictors of absence of recanalisation: Acute glucose > 7 mmol/l (A), significant extracranial vessel STenosis (ST), decreased Range of visual fields (R), large Arterial occlusion (A) and decreased Level of consciousness (L). All variables were weighted 1, except for (L) which obtained 2 points based on β-coefficients on the logistic scale. ASTRAL-R scores 0, 3 and 6 corresponded to non-recanalisation probabilities of 18, 44 and 74 % respectively. Predictive ability showed AUC of 0.66 (95 %CI, 0.61-0.70) when using bootstrap and 0.66 (0.63-0.68) when using delete-d cross validation. In conclusion, the 5-item ASTRAL-R score moderately predicts non-recanalisation at 24 hours in thrombolysed ischaemic strokes. If its performance can be confirmed by external validation and its clinical usefulness can be proven, the score may influence patient selection for more aggressive revascularisation strategies in routine clinical practice.

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