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result(s) for
"Obach, Víctor"
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Elevated glucose is associated with hemorrhagic transformation after mechanical thrombectomy in acute ischemic stroke patients with severe pretreatment hypoperfusion
2020
Several pretreatment variables such as elevated glucose and hypoperfusion severity are related to brain hemorrhage after endovascular treatment of acute stroke. We evaluated whether elevated glucose and severe hypoperfusion have synergistic effects in the promotion of parenchymal hemorrhage (PH) after mechanical thrombectomy (MT). We included 258 patients MT-treated who had a pretreatment computed tomography perfusion (CTP) and a post-treatment follow-up MRI. Severe hypoperfusion was defined as regions with cerebral blood volume (CBV) values < 2.5% of normal brain [very-low CBV (VLCBV)-regions]. Median baseline glucose levels were 119 (IQR = 105–141) mg/dL. Thirty-nine (15%) patients had pretreatment VLCBV-regions, and 42 (16%) developed a PH after MT. In adjusted models, pretreatment glucose levels interacted significantly with VLCBV on the prediction of PH (p-interaction = 0.011). In patients with VLCBV-regions, higher glucose was significantly associated with PH (adjusted-OR = 3.15; 95% CI = 1.08–9.19,
p
= 0.036), whereas this association was not significant in patients without VLCBV-regions. CBV values measured at pretreatment CTP in coregistered regions that developed PH or infarct at follow-up were not correlated with pretreatment glucose levels, thus suggesting the existence of alternative deleterious mechanisms other than direct glucose-driven hemodynamic impairments. Overall, these results suggest that both severe hypoperfusion and glucose levels should be considered in the evaluation of adjunctive neuroprotective strategies.
Journal Article
Monocyte Subtypes Predict Clinical Course and Prognosis in Human Stroke
by
Gómez-Choco, Manuel
,
Obach, Víctor
,
Amaro, Sergio
in
Aged
,
Biological and medical sciences
,
Blood Platelets - cytology
2009
The number of circulating monocytes increases after stroke. In this study, we assessed the time course and phenotype of monocyte subsets and their relationship with the clinical course and outcome in 46 consecutive stroke patients and 13 age-matched controls. The proportion of the most abundant ‘classical’ CD14highCD16 monocytes did not change after stroke, whereas that of CD14highCD16+ monocytes increased and CD14dimCD16+ monocytes decreased. CD14highCD16 + monocytes had the highest expression of TLR2, HLA-DR and the angiogenic marker, Tie-2; CD14dimCD16+ monocytes had the highest expression of costimulatory CD86 and adhesion molecule CD49d. Platelet-monocyte interactions were highest in CD14highCD16 monocytes and lowest in CD14dimCD16+ monocytes. In adjusted models, 1/CD14highCD16 monocytes were associated with poor outcome (OR: 1.38), higher mortality (OR: 1.40) and early clinical worsening (OR: 1.29); 2/CD14highCD16+ monocytes were inversely related to mortality (OR: 0.32); and 3/CD14dimCD16+ monocytes were inversely related to poor outcome (OR: 0.74) and infarction size (r= 0.45; P = 0.02). These results illustrate that the predominant monocyte subtype conveys harmful effects after stroke, which include stronger interaction with platelets. Alternatively, rarer subpopulations of monocytes are beneficial with a phenotype that could promote tissue repair and angiogenesis. Therefore, monitoring of monocyte subtypes may emerge as a useful tool at the bedside for stroke patients.
Journal Article
The Outcome of Patients with Mild Stroke Improves after Treatment with Systemic Thrombolysis
by
Obach, Víctor
,
Amaro, Sergio
,
Ariño, Helena
in
Administration, Intravenous
,
Aged
,
Aged, 80 and over
2013
In up to one third of patients with mild stroke suitable to receive systemic thrombolysis the treatment is not administered because the treating physicians estimate a good spontaneous recovery. However, it is not settled whether the fate of these patients is equivalent to those who are thrombolysed.
We analyzed 203 consecutive patients (134 men and 69 women, mean age 69±14 years) without premorbid disability and a NIHSS score ≤5 at admission [median 3 (IQR 2-4)]. Intravenous thrombolysis was administered within 4.5 hours from stroke onset (n = 119), or it was withheld (n = 84) whenever the treating physician predicted a spontaneous recovery. The baseline risk factors, clinical course, infarction volume, bleeding complications, and functional outcome at 3 months were analyzed and declared to a Web-based registry which was accessible to the local Health Authorities.
Expectedly, not thrombolysed patients had the mildest strokes at admission [median 2 (IQR 1-3.75)]. At day 2 to 5, the infarct volume on DWI-MRI was similar in both groups. There were no symptomatic cerebral bleedings in the study. An ordinal regression model adjusted for baseline stroke severity showed that thrombolysis was associated with a greater proportion of patients who shifted down on the modified Rankin Scale score at 3 months (OR 2.66; 95% CI 1.49-4.74, p = 0.001).
Intravenous thrombolysis seems to be safe in patients with mild stroke and may be associated with improved outcome compared with untreated patients. These results support the evaluation of the efficacy of intravenous thrombolysis in mild stroke patients in randomized clinical trials.
Journal Article
Risks and Benefits of Early Antithrombotic Therapy after Thrombolytic Treatment in Patients with Acute Stroke
2013
Current guidelines recommend withholding antithrombotic therapy (ATT) for at least 24 h in patients with acute ischemic stroke treated with thrombolytic therapy. Herein, we report a retrospective analysis of a single-centre experience on the safety and efficacy of antithrombotic therapy (ATT) started before or after 24 h of intravenous thrombolysis in a cohort of acute ischemic stroke patients.
A total of 139 patients (Rapid ATT group) received antithrombotic therapy before 24 h of thrombolysis, and 33 patients (Standard ATT group) after 24 h. The brain parenchyma and vessel status were assessed using simple CT scan on admission, multimodal CT scan at the end of thrombolysis, and angio-CT/MRI scan at day 3. Functional outcome was scored using the modified Rankin Scale (mRS) at day 90.
The two ATT groups had similar demographics, stroke subtypes, baseline NIHSS, thrombolytic strategies, vessel-patency rates at the end of thrombolysis, and incidence of bleeding complications at follow up. At day 3, the Rapid ATT group had a non-significant improved vessel-patency rate than the Standard ATT group. At day 90, a greater proportion of patients in the rapid ATT group had shifted down the mRS, and had improved in the NIHSS score.
ATT initiated before 24 h of intravenous thrombolytic therapy in acute stroke patients disclosed no safety concerns compared with a conventional antithrombotic therapy delay of 24 h and showed better functional outcome at follow up. The value of early initiation of ATT after thrombolysis deserves further assessment in randomized controlled trials.
Journal Article
The Basilar Artery International Cooperation Study (BASICS): study protocol for a randomised controlled trial
2013
Background
Despite recent advances in acute stroke treatment, basilar artery occlusion (BAO) is associated with a death or disability rate of close to 70%. Randomised trials have shown the safety and efficacy of intravenous thrombolysis (IVT) given within 4.5 h and have shown promising results of intra-arterial thrombolysis given within 6 h of symptom onset of acute ischaemic stroke, but these results do not directly apply to patients with an acute BAO because only few, if any, of these patients were included in randomised acute stroke trials.
Recently the results of the Basilar Artery International Cooperation Study (BASICS), a prospective registry of patients with acute symptomatic BAO challenged the often-held assumption that intra-arterial treatment (IAT) is superior to IVT. Our observations in the BASICS registry underscore that we continue to lack a proven treatment modality for patients with an acute BAO and that current clinical practice varies widely.
Design
BASICS is a randomised controlled, multicentre, open label, phase III intervention trial with blinded outcome assessment, investigating the efficacy and safety of additional IAT after IVT in patients with BAO. The trial targets to include 750 patients, aged 18 to 85 years, with CT angiography or MR angiography confirmed BAO treated with IVT. Patients will be randomised between additional IAT followed by optimal medical care versus optimal medical care alone. IVT has to be initiated within 4.5 h from estimated time of BAO and IAT within 6 h. The primary outcome parameter will be favourable outcome at day 90 defined as a modified Rankin Scale score of 0–3.
Discussion
The BASICS registry was observational and has all the limitations of a non-randomised study. As the IAT approach becomes increasingly available and frequently utilised an adequately powered randomised controlled phase III trial investigating the added value of this therapy in patients with an acute symptomatic BAO is needed (clinicaltrials.gov: NCT01717755).
Journal Article
Clinical improvement within 24 hours from mechanical thrombectomy as a predictor of long-term functional outcome in a multicenter population-based cohort of patients with ischemic stroke
by
Amaro, Sergio
,
Roquer, Jaume
,
Serena, Joaquín
in
Aged
,
Aged, 80 and over
,
Brain Ischemia - diagnosis
2021
BackgroundSingle-center studies have suggested that the early clinical course after mechanical thrombectomy (MT) in patients with ischemic stroke is a clinical predictor of long-term outcome.ObjectiveTo analyze the prognostic value of clinical improvement within 24 hours in a population-based multicenter cohort.MethodsFrom a total of 3792 patients with acute ischemic stroke in Catalonia (CICAT registry), 1951 patients were treated with MT. The National Institutes of Health Stroke Scale (NIHSS) score within 24 hours, and follow-up was available in 1666 patients. Percentage variation in the NIHSS score was calculated in relation to a baseline assessment. Good outcome was defined as a modified Rankin Scale score ≤2 at 90 days. Predictive values of clinical improvement and adjusted OR to predict good outcomes were assessed in the whole cohort and the subgroup of patients with posterior circulation stroke (n=166).ResultsGood outcome was achieved in 656/1666 patients (39%) overall. Percentage improvements both at the end of MT and at 24 hours predicted good outcome, with higher predictive capacity at 24 hours (C-statistic, 0.85 vs 0.73, p<0.001). Positive and negative predictive values were 70% and 74% for the >30% cut-off point at the end of MT, and 69% and 84% for the >50% cut-off point at 24 hours, respectively. The adjusted OR for good outcome was 5.8 (95% CI 4.2 to 8.1) and 12.9 (95% CI 9.7 to 17.1), respectively. In patients with posterior circulation stroke, the predictive value of the improvement at 24 hours was similar (C-statistic 0.90).ConclusionClinical improvement of patients within 24 hours of MT is a reliable and robust predictor of long-term prognosis, including patients with posterior circulation occlusions.
Journal Article
Course of matrix metalloproteinase-9 isoforms after the administration of uric acid in patients with acute stroke
by
Obach, Víctor
,
Gómez-Choco, Manuel
,
Amaro, Sergio
in
Aged
,
Antioxidants
,
Antioxidants - administration & dosage
2009
Oxidative stress as well as expression and activity of matrix metalloproteinase 9 (MMP-9) are rapidly enhanced after cerebral ischemia. The magnitude of these effects is related to stroke outcome. In human stroke, the extent of oxidative stress correlates well with increased MMP-9 expression. The aim of this study was to evaluate whether treatment with the antioxidant molecule uric acid (UA) decreased the levels of MMP-9 in stroke patients treated with rtPA. The patients were part of a pilot, double-blind, randomized, vehiclecontrolled study of patients with acute stroke treated with rtPA (< 3 h) and randomized to receive an intravenous infusion of UA (n = 16) or vehicle (n = 8). Total matrix metalloproteinase (tMMP)-9 and active (aMMP-9) levels were measured in serum at baseline (< 3 h), at the end of study treatment infusion (< 5.5 h), and at 48 hours. Total MMP-9 and aMMP-9 increased very early after stroke onset in patients allocated vehicle after rtPA therapy. Lower increments of aMMP-9 were associated with better outcome at 3 months. UA treatment was associated with reduced levels of aMMP-9 at T1 (p < 0.02) in multivariate models adjusted for age, NIHSS score, and baseline aMMP-9 levels. The decline of aMMP-9 attained after UA administration supports further clinical assessment of UA therapy in patients with acute stroke.
Journal Article
Complete reperfusion is required for maximal benefits of mechanical thrombectomy in stroke patients
2017
A mTICI 2b or a mTICI 3 score are currently considered success following mechanical thrombectomy (MT) in acute stroke but is undetermined whether the two scores translate equivalent outcomes. We present a single-center, retrospective cohort of patients with anterior circulation stroke treated with MT and achieving a final mTICI score 2b or 3. A multimodal CT at baseline and a multimodal MRI at 24 hours assessed the growth of the infarct, and the modified Rankin Scale (mRS) assessed functional outcome at 90 days. The primary outcome was the shift analysis of the mRS at day 90 in ordinal regression adjusted for covariates (age, sex, pretreatment NIHSS score, target occlusion, infarct core, pretreatment alteplase), and the collateral score. Infarct growth was explored in a similarly adjusted multiple linear regression model. MT was started within a median of 285 minutes of symptom onset; 51 (41%) patients achieved a mTICI 2b, and 74 (59%), a mTICI 3. mTICI 3 resulted in better mRS score transitions than mTICI 2b (odds ratio 2.018 [95% CI 1.033–3.945], p = 0. 040), and reduced infarct growth (p = 0.002). We conclude that in patients with acute stroke receiving MT, success should be redefined as achieving a mTICI 3 score.
Journal Article
Large APP locus duplication in a sporadic case of cerebral haemorrhage
by
Obach, Víctor
,
Gelpi, Ellen
,
Amaro, Sergio
in
Alzheimer Disease - genetics
,
Amyloid beta-Protein Precursor - genetics
,
Asymptotic methods
2014
We report a 54-year-old man who was admitted to the hospital because of acute neurological symptoms due to a cerebral haemorrhage. Postmortem brain examination revealed a lobar haemorrhage and advanced AD neuropathologic changes associated with severe cerebral amyloid angiopathy. Genetic study evidenced the presence of a large
APP
locus duplication (APPdup) in the patient and a
PSEN1
p.E318G polymorphism in him and his older asymptomatic sibling. The APPdup spanned 14.5 Mb and blocks of segmental duplications were detected in the breakpoints. We propose the replication-based mechanism of Fork Stalling Template Switching (FoSTeS) to explain this APPdup rearrangement.
Journal Article
Frequency and Predictors of Symptomatic Intracerebral Hemorrhage in Patients with Ischemic Stroke Treated with Recombinant Tissue Plasminogen Activator outside Clinical Trials
by
Roquer, Jaume
,
Castellanos, Mar
,
Martí-Vilalta, Josep-Lluis
in
Aged
,
Cerebral Hemorrhage - chemically induced
,
Cerebral Hemorrhage - diagnostic imaging
2007
Background: To determine the frequency and predictors of symptomatic intracerebral hemorrhage (SICH) in patients treated with recombinant tissue plasminogen activator (rt-PA). Methods: We reviewed the databases of 7 tertiary hospitals that treated ischemic stroke patients with intravenous rt-PA. We recorded demographic data, vascular risk factors, time between onset and treatment, dose, the NIHSS score, body temperature, blood pressure, platelet count, blood glucose, antiplatelet treatment, and CT data. We also registered the study protocol used for treatment and deviations from the accepted protocol. A control CT was performed on all patients. SICH was diagnosed if a parenchymal hematoma was detected within the 36 h after rt-PA and was associated with an increase of ≧4 in the NIHSS score. Bivariate analyses were performed followed by a logistic regression analysis. Results: A total of 347 patients were studied, whose mean age was 68 ± 10.9 years; 56% were men. Thirty-two patients (9.2%) exhibited a parenchymal hematoma, and 8 patients (2.3%) suffered a SICH. Patients with SICH had a higher frequency of previous transient ischemic attack (p = 0.04), early signs of ischemia (p = 0.003), hyperdense arterial sign (p = 0.008), and deviations (p = 0.002). Early signs of ischemia (OR 8.5, 95% CI 1.6–45.4, p = 0.01) and deviation from the protocol (OR 11.1, 95% CI 2.4–50, p = 0.002) were independent predictors of SICH. Conclusions: SICH is infrequent in patients with ischemic stroke treated with rt-PA outside of a clinical trial. Its frequency increases in the presence of early signs of ischemia on the noncontrast CT scan and deviations from the recommended protocol.
Journal Article