1,720,982 research outputs found
Premio nazionale per la ricerca sull'ictus cerebrale "HIPPONION – ISA-AII"
No full textBackground: Futile recanalization (FR) is defined as poor 90 outcome or lack of neurological
improvement at 24 hours despite successful recanalization in AIS with LVO treated by mechanical
throbectomy (MT).
No-reflow phenomenon (NRP) could be a possible cause of FR but its evidence in AIS patients is
scarce.
Methods: We retrospectively analyzed 185 digital subtraction angiographies (DSA) of AIS patients
with anterior circulation LVO after endovascular treatment (EVT). In order to better define NRP,
we designed a score called modified capillary index score (mCIS). The score is obtained by
dividing middle cerebral artery territory in three segments. For each segment we gave 2 points if the
capillary blush was present without any delay, 1 if delayed and 0 if absent. The primary endpoint
2
was to use mCIS to identify NRP on post-interventional DSA and to test whether this marker may
predict FR and fENI. Secondary endpoint was to search a correlation between NRP, lesion volume
and hemorrhagic transformation. We used ROC curve to define mCIS≤3 as cut-off and marker of
NRP.
Results: NRP was present in 35.1% of patients. NRP predicted fENI at 24h (aOR 2.825, 95%CI
1.265–6.308, P=0.011) and at 7 days (aOR 2.191, 95%CI 1,008-4.762, P=0.048), but not 90-day
FR. Moreover, NRP predicted hemorrhagic transformation (aOR2.444, 95%CI 1.266–4.717,
P=0.008).
Conclusions: Modified capillary index score (mCIS) seems useful in identifying NRP in AIS
patients. In addition, mCIS was able to predict NRP that correlated with early clinical outcome and
hemorrhagic transformation of the ischemic lesion. An external validation of the score is warranted
Valutazione angiografica e ruolo di endotelina-1 ed ossido nitrico nel no-reflow phenomenon in pazienti con ictus ischemico acuto da occlusione dei grossi vasi trattati con successo con trombectomia meccanica
No full textBackground. Futile recanalization (FR), defined as a 90-day mRS 3-6 despite successful recanalization, account for 29% to 60% of large vessel occlusion (LVO) acute ischemic stroke (AIS) treated with mechanical thrombectomy (MT). Failure of early neurological improvement (fENI) describes patients successfully recanalized but not clinically improving at 24-hours or at 7-days.
No-reflow phenomenon (NRP) is a possible cause of FR and fENI, described in animal models and myocardial infarction as deficient microvascular reperfusion. Evidence of NRP in AIS patients is scarce.
Proposed determinants of NRP include vasoactive agents such as Endothelin-1 (ET-1) and Nitric oxide (NO), possibly involved in microvascular disfunction of NRP.
Aim of our research was to define NRP in AIS from LVO of the anterior circulation treated with MT with successful recanalization.
STUDY 1.
Methods. We retrospectively analyzed 185 post-interventional digital subtraction angiographies (DSA) of anterior circulation LVO AIS patients treated with MT. We created a score, called modified capillary index score (mCIS), dividing middle cerebral artery territory in three segments. For each segment we gave 2 points if the capillary blush was present without any delay, 1 if delayed and 0 if absent. We used ROC curve to define mCIS≤3 as cut-off and marker of NRP. The primary endpoint was to identify a marker of NRP on post interventional DSA and to test whether this marker may predict FR and fENI. Secondary endpoint was to search a correlation between NRP, lesion volume and hemorrhagic transformation.
Results. NRP was present in 35.1% of patients. NRP predicted fENI at 24h (aOR2.617, 95%CI1.192–5.745, p=0.016) and at 7 days (aOR4.601, 95%CI1.636–12.936, p=0.004), but not FR. Moreover, NRP predicted hemorrhagic transformation (aOR2.444, 95%CI 1.266–4.717, p=0.008).
Discussion. NRP is poorly investigated in AIS. We identified an angiographic score able to identify NRP in AIS patients. Our angiographic marker was able to predict early outcome and hemorrhagic transformation of the ischemic lesion.
STUDY 2.
Methods. We prospectively enrolled 61 patients with AIS from LVO of the anterior circulation, successfully treated with MT. Patients were divided in groups according to the presence of NRP, as defined in study1. Peripheral venous blood samples were taken to dose ET-1 and NO at admission, after 24 and 48 hours. When technically possible, intracranial arterial blood samples, before and after recanalization, were taken. Primary endpoint was to test the association between ET-1 and NO levels and NRP. Secondary endpoint was to explore the association between ET-1 and NO levels and clinical outcome.
Results. NRP Patients showed lower pre-MT intracranial levels of NO (9.60 μM ±2.80 vs 18.58 μM ±5.92, p=0.004) but the association was not confirmed at logistic regression (aOR0.561, 95%CI 0.297–1.061, p=0.075). Mean peripheral NO levels at 48 hours were 20.46 μM ±7.08 in the NRP group and 14.00 μM ± 8.06 in the no-NRP group (p=0.084). fENI at 24h was associated to lower serum NO levels at 24h (aOR1.19, 95%CI 1.014–1.213, p=0.023).
Discussion. Our study tried to explore the role of ET-1 and NO in NRP. The trend to lower pre-MT levels of NO, might be the consequence of a reduced activity of the endothelial isoform of nitric oxide synthase (NOS). The increased values of NO at 24h in NRP patients might be due to the activation of the neuronal NOS. NO rather than ET-1 seems to have a major role in NRP.
Conclusion. Reperfusion of main arteries in AIS from LVO is not always sufficient to ensure clinical improvement, a possible cause might be deficient microvascular reperfusion. We identified a marker of NRP in AIS patients, which could represent a useful tool to study this poorly recognized condition. Furthermore, we outlined a possible role of NO in NRP.
Our data may contribute to future research studying NRP pathophysiology and possibly treatment.Background. Futile recanalization (FR), defined as a 90-day mRS 3-6 despite successful recanalization, account for 29% to 60% of large vessel occlusion (LVO) acute ischemic stroke (AIS) treated with mechanical thrombectomy (MT). Failure of early neurological improvement (fENI) describes patients successfully recanalized but not clinically improving at 24-hours or at 7-days.
No-reflow phenomenon (NRP) is a possible cause of FR and fENI, described in animal models and myocardial infarction as deficient microvascular reperfusion. Evidence of NRP in AIS patients is scarce.
Proposed determinants of NRP include vasoactive agents such as Endothelin-1 (ET-1) and Nitric oxide (NO), possibly involved in microvascular disfunction of NRP.
Aim of our research was to define NRP in AIS from LVO of the anterior circulation treated with MT with successful recanalization.
STUDY 1.
Methods. We retrospectively analyzed 185 post-interventional digital subtraction angiographies (DSA) of anterior circulation LVO AIS patients treated with MT. We created a score, called modified capillary index score (mCIS), dividing middle cerebral artery territory in three segments. For each segment we gave 2 points if the capillary blush was present without any delay, 1 if delayed and 0 if absent. We used ROC curve to define mCIS≤3 as cut-off and marker of NRP. The primary endpoint was to identify a marker of NRP on post interventional DSA and to test whether this marker may predict FR and fENI. Secondary endpoint was to search a correlation between NRP, lesion volume and hemorrhagic transformation.
Results. NRP was present in 35.1% of patients. NRP predicted fENI at 24h (aOR2.617, 95%CI1.192–5.745, p=0.016) and at 7 days (aOR4.601, 95%CI1.636–12.936, p=0.004), but not FR. Moreover, NRP predicted hemorrhagic transformation (aOR2.444, 95%CI 1.266–4.717, p=0.008).
Discussion. NRP is poorly investigated in AIS. We identified an angiographic score able to identify NRP in AIS patients. Our angiographic marker was able to predict early outcome and hemorrhagic transformation of the ischemic lesion.
STUDY 2.
Methods. We prospectively enrolled 61 patients with AIS from LVO of the anterior circulation, successfully treated with MT. Patients were divided in groups according to the presence of NRP, as defined in study1. Peripheral venous blood samples were taken to dose ET-1 and NO at admission, after 24 and 48 hours. When technically possible, intracranial arterial blood samples, before and after recanalization, were taken. Primary endpoint was to test the association between ET-1 and NO levels and NRP. Secondary endpoint was to explore the association between ET-1 and NO levels and clinical outcome.
Results. NRP Patients showed lower pre-MT intracranial levels of NO (9.60 μM ±2.80 vs 18.58 μM ±5.92, p=0.004) but the association was not confirmed at logistic regression (aOR0.561, 95%CI 0.297–1.061, p=0.075). Mean peripheral NO levels at 48 hours were 20.46 μM ±7.08 in the NRP group and 14.00 μM ± 8.06 in the no-NRP group (p=0.084). fENI at 24h was associated to lower serum NO levels at 24h (aOR1.19, 95%CI 1.014–1.213, p=0.023).
Discussion. Our study tried to explore the role of ET-1 and NO in NRP. The trend to lower pre-MT levels of NO, might be the consequence of a reduced activity of the endothelial isoform of nitric oxide synthase (NOS). The increased values of NO at 24h in NRP patients might be due to the activation of the neuronal NOS. NO rather than ET-1 seems to have a major role in NRP.
Conclusion. Reperfusion of main arteries in AIS from LVO is not always sufficient to ensure clinical improvement, a possible cause might be deficient microvascular reperfusion. We identified a marker of NRP in AIS patients, which could represent a useful tool to study this poorly recognized condition. Furthermore, we outlined a possible role of NO in NRP.
Our data may contribute to future research studying NRP pathophysiology and possibly treatment
Emergenze e urgenze medico-chirurgiche. Sintomo diagnosi terapia
No full textChi esercita la propria attività in area di emergenza, sia ospedaliera sia territoriale, necessita di un continuo aggiornamento e di un supporto nelle scelte cliniche e organizzative. Oggi è sempre maggiore la richiesta di interventi non solo efficaci, ma anche appropriati ed efficienti; il tema dell'organizzazione, dei tempi, delle modalità e della sicurezza di erogazione delle cure, è quindi cruciale anche per i risvolti medico-legali e alla luce delle più recenti disposizioni normative. Il volume concilia l'autorevolezza della letteratura internazionale più recente - le ultime linee guida, le buone pratiche clinico-assistenziali e le raccomandazioni basate sulle evidenze scientifiche - con la praticità dei manuali professionali. Numerose procedure vengono infatti spiegante nel dettaglio tra cui i blocchi nervosi regionali, le tecniche di sutura e gli accessi venosi centrale e periferici. Grande spazio è dedicato alla gestione avanzata delle vie aeree, con la toracentesi, la rachicentesi e la pericardiocentesi. Tutti i medici che lavorano nell'area dell'emergenza e urgenza avranno in questo testo un riferimento per l'approccio diagnostico-terapeutico e la gestione clinica del paziente acuto
Interventistica cardiovascolare nella prevenzione e trattamento dello stroke
No full textLo stroke rappresenta globalmente una delle maggiori cause di morte e disabilità permanente. L’interventistica cardiovascolare ha contribuito notevolmente ai numerosi progressi ottenuti nella prevenzione e trattamento dello stroke. In questo volume, edito da Minerva Medica e curato dalla Società Italiana di Cardiologia Interventistica (SICI-GISE), gli autori hanno affrontato in dettaglio le numerose tematiche che coinvolgono i cardiologi nella gestione di quest’importante patologia. In particolare, l’opera si divide in cinque principali sezioni che comprendono: gli approcci farmacologici allo stroke, la chiusura del forame ovale pervio (PFO), la chiusura dell’auricola sinistra, l’angioplastica carotidea e la valutazione peri- e post-operatoria dei pazienti con patologia valvolare. Il volume è stato concepito avendo come destinataria l’intera comunità cardiologica, inclusi i cardiologi clinici e quelli interventisti
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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