Person: Olavarría, Verónica V.
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Olavarría
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Verónica V.
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Publication Diffusion-weighted imaging as predictor of acute ischemic stroke etiology(2022) brunser, alejandro; Mansilla, Eloy; NAVIA, VICTOR; Mazzon, Enrico; Rojo, Alexis; Cavada, Gabriel; Olavarría, Verónica V.; Munoz Venturelli, Paula; Lavados, PabloBackground: Topographic patterns may correlate with causes of ischemic stroke. Objective: To investigate the association between diffusion weighted imaging (DWI) and Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. Methods: We included 1019 ischemic stroke patients. DWI were classified as: i) negative; ii) DWI single lesion (cortico-subcortical, cortical, subcortical ≥20 mm, or subcortical <20 mm); iii) scattered lesions in one territory (small scattered lesions or confluent with additional lesions); and iv) multiple lesions (multiple unilateral anterior circulation [MAC], multiple posterior circulation [MPC], multiple bilateral anterior circulation [MBAC], and multiple anterior and posterior circulations [MAP]). Results: There was a relationship between DWI patterns and TOAST classification (p<0.001). Large artery atherosclerosis was associated with small, scattered lesions in one vascular territory (Odds Ratio [OR] 4.22, 95% confidence interval [95%CI] 2.61–6.8), MPC (OR 3.52; 95%CI 1.54–8.03), and subcortical lesions <20 mm (OR 3.47; 95%CI 1.76–6.85). Cardioembolic strokes correlated with MAP (OR 4.3; 95%CI 1.64–11.2), cortico-subcortical lesions (OR 3.24; 95%CI 1.9–5.5) and negative DWI (OR 2.46; 95%CI 1.1–5.49). Cryptogenic strokes correlated with negative DWI (OR 4.1; 95%CI 1,84–8.69), cortical strokes (OR 3.3; 95%CI 1.25–8.8), MAP (OR 3.33; 95%CI 1.25–8.81) and subcortical lesion ≥20 mm (OR 2.44; 95%CI 1,04–5.73). Lacunar strokes correlated with subcortical lesions diameter <20 mm (OR 42.9; 95%CI 22.7–81.1) and negative DWI (OR 8.87; 95%CI 4.03–19.5). Finally, MBAC (OR 9.25; 95%CI 1.12–76.2), MAP (OR 5.54; 95%CI 1.94–15.1), and MPC (OR 3.61; 95%CI 1.5–8.7) correlated with stroke of other etiologies. Conclusions: A relationship exists between DWI and stroke subtypePublication Who is in the emergency room matters when we talk about door-to-needle time: a single-center experience(2023) brunser, alejandro; Nuñez, Juan Cristobal; Mansilla, Eloy; Cavada, Gabriel; Olavarría, Verónica V.; Munoz Venturelli, Paula; Lavados, PabloBackground: The efficacy of intravenous thrombolysis (IVT) is time-dependent. Objective: To compare the door-to-needle (DTN) time of stroke neurologists (SNs) versus non-stroke neurologists (NSNs) and emergency room physicians (EPs). Additionally, we aimed to determine elements associated with DTN ≤ 20 minutes. Methods: Prospective study of patients with IVT treated at Clínica Alemana between June 2016 and September 2021. Results: A total of 301 patients underwent treatment for IVT. The mean DTN time was 43.3 ± 23.6 minutes. One hundred seventy-three (57.4%) patients were evaluated by SNs, 122 (40.5%) by NSNs, and 6 (2.1%) by EPs. The mean DTN times were 40.8 ± 23, 46 ± 24.7, and 58 ± 22.5 minutes, respectively. Door-to-needle time ≤ 20 minutes occurred more frequently when patients were treated by SNs compared to NSNs and EPs: 15%, 4%, and 0%, respectively (odds ratio [OR]: 4.3, 95% confidence interval [95%CI]: 1.66-11.5, p = 0.004). In univariate analysis DTN time ≤ 20 minutes was associated with treatment by a SN (p = 0.002), coronavirus disease 2019 pandemic period (p = 0.21), time to emergency room (ER) (p = 0.21), presence of diabetes (p = 0.142), hypercholesterolemia (p = 0.007), atrial fibrillation (p < 0.09), score on the National Institutes of Health Stroke Scale (NIHSS) (p = 0.001), lower systolic (p = 0.143) and diastolic (p = 0.21) blood pressures, the Alberta Stroke Program Early CT Score (ASPECTS; p = 0.09), vessel occlusion (p = 0.05), use of tenecteplase (p = 0.18), thrombectomy (p = 0.13), and years of experience of the physician (p < 0.001). After multivariate analysis, being treated by a SN (OR: 3.95; 95%CI: 1.44-10.8; p = 0.007), NIHSS (OR: 1.07; 95%CI: 1.02-1.12; p < 0.002) and lower systolic blood pressure (OR: 0.98; 95%CI: 0.96-0.99; p < 0.003) remained significant. Conclusion: Treatment by a SN resulted in a higher probability of treating the patient in a DTN time within 20 minutes.Publication Effects of intensive blood pressure lowering on cerebral ischaemia in thrombolysed patients: insights from the ENCHANTED trial(2023) Chen, Chen; Ouyang, Menglu; Ong, Sheila; Zhang, Luyun; Zhang, Guobin; Delcourt, Candice; Mair, Grant; Liu, Leibo; Billot, Laurent; Li, Qiang; Chen, Xiaoying; Parsons, Mark; Broderick, Joseph; Demchuk, Andrew; Bath, Philip; Donnan, Geoffrey; Levi, Christopher; Chalmers, John; Lindley, Richard; Martins, Sheila; Pontes-Neto, Octavio; Munoz Venturelli, Paula; Olavarría, Verónica V.; Lavados, Pablo; Robinson, Thompson; Wardlaw, Joanna; Li, Gang; Wang, Xia; Song, Lili; Anderson, CraigBackground: Intensive blood pressure lowering may adversely affect evolving cerebral ischaemia. We aimed to determine whether intensive blood pressure lowering altered the size of cerebral infarction in the 2196 patients who participated in the Enhanced Control of Hypertension and Thrombolysis Stroke Study, an international randomised controlled trial of intensive (systolic target 130-140 mm Hg within 1 h; maintained for 72 h) or guideline-recommended (systolic target <180 mm Hg) blood pressure management in patients with hypertension (systolic blood pressure >150 mm Hg) after thrombolysis treatment for acute ischaemic stroke between March 3, 2012 and April 30, 2018. Methods: All available brain imaging were analysed centrally by expert readers. Log-linear regression was used to determine the effects of intensive blood pressure lowering on the size of cerebral infarction, with adjustment for potential confounders. The primary analysis pertained to follow-up computerised tomography (CT) scans done between 24 and 36 h. Sensitivity analysis were undertaken in patients with only a follow-up magnetic resonance imaging (MRI) and either MRI or CT at 24-36 h, and in patients with any brain imaging done at any time during follow-up. This trial is registered with ClinicalTrials.gov, number NCT01422616. Findings: There were 1477 (67.3%) patients (mean age 67.7 [12.1] y; male 60%, Asian 65%) with available follow-up brain imaging for analysis, including 635 patients with a CT done at 24-36 h. Mean achieved systolic blood pressures over 1-24 h were 141 mm Hg and 149 mm Hg in the intensive group and guideline group, respectively. There was no effect of intensive blood pressure lowering on the median size (ml) of cerebral infarction on follow-up CT at 24-36 h (0.3 [IQR 0.0-16.6] in the intensive group and 0.9 [0.0-12.5] in the guideline group; log Δmean -0.17, 95% CI -0.78 to 0.43). The results were consistent in sensitivity and subgroup analyses. Interpretation: Intensive blood pressure lowering treatment to a systolic target <140 mm Hg within several hours after the onset of symptoms may not increase the size of cerebral infarction in patients who receive thrombolysis treatment for acute ischaemic stroke of mild to moderate neurological severity. Funding: National Health and Medical Research Council of Australia; UK Stroke Association; UK Dementia Research Institute; Ministry of Health and the National Council for Scientific and Technological Development of Brazil; Ministry for Health, Welfare, and Family Affairs of South Korea; Takeda.Publication Who is in the emergency room matters when we talk about door-to-needle time: a single-center experience [Quien está en el servicio de emergencia importa al hablar de tiempo puerta-aguja: experiencia de un centro clínico](2023) brunser, alejandro; Nuñez; Juan; Mansilla, Eloy; Cavada, Gabriel; Olavarría, Verónica V.; Munoz Venturelli, Paula; Lavados, PabloBackground: The efficacy of intravenous thrombolysis (IVT) is time-dependent. Objective: To compare the door-to-needle (DTN) time of stroke neurologists (SNs) versus non-stroke neurologists (NSNs) and emergency room physicians (EPs). Additionally, we aimed to determine elements associated with DTN ≤ 20 minutes. Methods: Prospective study of patients with IVT treated at Clínica Alemana between June 2016 and September 2021. Results: A total of 301 patients underwent treatment for IVT. The mean DTN time was 43.3 ± 23.6 minutes. One hundred seventy-three (57.4%) patients were evaluated by SNs, 122 (40.5%) by NSNs, and 6 (2.1%) by EPs. The mean DTN times were 40.8 ± 23, 46 ± 24.7, and 58 ± 22.5 minutes, respectively. Door-to-needle time ≤ 20 minutes occurred more frequently when patients were treated by SNs compared to NSNs and EPs: 15%, 4%, and 0%, respectively (odds ratio [OR]: 4.3, 95% confidence interval [95%CI]: 1.66–11.5, p = 0.004). In univariate analysis DTN time ≤ 20 minutes was associated with treatment by a SN ( p = 0.002), coronavirus disease 2019 pandemic period ( p = 0.21), time to emergency room (ER) ( p = 0.21), presence of diabetes ( p = 0.142), hypercholesterolemia ( p = 0.007), atrial fibrillation ( p < 0.09), score on the National Institutes of Health Stroke Scale (NIHSS) ( p = 0.001), lower systolic ( p = 0.143) and diastolic ( p = 0.21) blood pressures, the Alberta Stroke Program Early CT Score (ASPECTS; p = 0.09), vessel occlusion ( p = 0.05), use of tenecteplase ( p = 0.18), thrombectomy ( p = 0.13), and years of experience of the physician ( p < 0.001). After multivariate analysis, being treated by a SN (OR: 3.95; 95%CI: 1.44–10.8; p = 0.007), NIHSS (OR: 1.07; 95%CI: 1.02–1.12; p < 0.002) and lower systolic blood pressure (OR: 0.98; 95%CI: 0.96–0.99; p < 0.003) remained significant. Conclusion: Treatment by a SN resulted in a higher probability of treating the patient in a DTN time within 20 minutes.Publication Correlation between dual-phase CTA-SI ASPECTS and automated CT perfusion imaging in patients with acute ischemic stroke beyond the 6-hour window(2023) Gallardo, Andrés; Lavados, Pablo; Cox, Pablo; Barra, Camila de la; Cavada, Gabriel; Olavarría, Verónica V.Background/Objective: There is controversy regarding the need to use advanced imaging to select candidates for thrombectomy in late window acute ischemic stroke (AIS). Hypoattenuation on CT angiography source images (CTA-SI) in arterial phase has been shown to be more sensitive than Alberta Stroke Program Early CT Score (ASPECTS) of brain parenchyma to determine tissue at risk of ischemia. Our hypothesis is that the addition of a second acquisition at 35-50 seconds could complement the assessment of hypoperfused tissue that fails to receive flow through pial vessels. Methods: Patients with large vessel occlusion and 6-24 hours from symptom onset, admitted between August 2019 and July 2023, were evaluated with dual-phase CT angiography (CTA) and CT-Perfusion. A vascular neurologist estimated CTA-SI ASPECTS in both phases at the time of data entry into the RECCA registry. In contrast, the post-processing of CT-Perfusion images was performed in an automated way through RAPID© software. The association between automated CT-perfusion values and dual-phase CTA-SI ASPECTS was assessed through a correlation coefficient. Results: Pearson’s coefficient demonstrated a high correlation between ischemic core volume and delayed phase CTA (CTA-DP) ASPECTS with an inverse association of −0.93 and between Tmax ≥ 6 sec volume and arterial phase CTA (CTA-AP) ASPECTS with a value of −0.88. Conclusions: CTA-derived source images (CTA-SI) in two phases may be useful in the selection of patients with AIS presenting beyond the 6-hour window.