Acute symptomatic seizures and epilepsy after mechanical thrombectomy. A prospective long-term follow-up study

INTRODUCTION

New treatments for acute ischaemic stroke, such as mechanical thrombectomy, can achieve reperfusion of large ischaemic tissue. Some studies have suggested that reperfusion therapies can increase the risk of suffering acute symptomatic seizure (ASS) and poststroke epilepsy (PSE). The aim of the study was to determine the incidence of ASS and PSE in patients undergoing thrombectomy, and related factors.

PATIENTS AND METHODS

This was a retrospective single-centre study including patients with ischaemic stroke and NIHSS> 8 treated with thrombectomy with a follow-up ≥5 years. We evaluated several epidemiological, radiological, clinical and electroencephalographic variables.

RESULTS

Of the 344 included patients, 21 (6.1%) presented ASS, 53 (15.40%) died in the acute phase, and 13 (4.46%) died during the first year. The degree of reperfusion (p 0.029), advanced age (p 0.035), and haemorrhagic transformation (p 0.038) increased the risk of suffering ASS, with degree of reperfusion being an independent factor, OR 2.02 (1.21-4.64). The incidence of PSE was 4.12% in the first year, 3.72% in the second, and 1.61% in the fifth. The accumulated incidence at 5 years was 8.93%. Related risk factor for suffering PSE was ASS (p < 0.001), yielding an OR value of 2.00 (1.28-3.145).

CONCLUSIONS

Thrombectomy doesn´t increase the risk of ASS. A higher percentage of reperfusion, advanced age, and haemorrhagic transformation are associated with an increased risk of ASS. ASS is a risk factor for suffering PSE. In terms of mortality, having suffered ASS and/or PSE does not increase acute or long-term mortality.

Outcomes After Direct Thrombectomy or Combined Intravenous and Endovascular Treatment Are Not Different

Background and Purpose—

Whether intravenous thrombolysis adds a further benefit when given before endovascular thrombectomy (EVT) is unknown. Furthermore, intravenous thrombolysis delays time to groin puncture, mainly among drip and ship patients.

Methods—

Using region-wide registry data, we selected cases that received direct EVT or combined intravenous thrombolysis+EVT for anterior circulation strokes between January 2011 and October 2015. Treatment effect was estimated by stratification on a propensity score. The average odds ratios for the association of treatment with good outcome and death at 3 months and symptomatic bleedings at 24 hours were calculated with the Mantel–Haenszel test statistic.

Results—

We included 599 direct EVT patients and 567 patients with combined treatment. Stratification through propensity score achieved balance of baseline characteristics across treatment groups. There was no association between treatment modality and good outcome (odds ratio, 0.97; 95% confidence interval, 0.74–1.27), death (odds ratio, 1.07; 95% confidence interval, 0.74–1.54), or symptomatic bleedings (odds ratio, 0.56; 95% confidence interval, 0.25–1.27).

Conclusions—

This observational study suggests that outcomes after direct EVT or combined intravenous thrombolysis+EVT are not different. If confirmed by a randomized controlled trial, it may have a significant impact on organization of stroke systems of care.

Access to Endovascular Treatment in Remote Areas

Background and Purpose—

Since demonstration of the benefit of endovascular treatment (EVT) in acute ischemic stroke patients with proximal arterial occlusion, stroke care systems need to be reorganized to deliver EVT in a timely and equitable way. We analyzed differences in the access to EVT by geographical areas in Catalonia, a territory with a highly decentralized stroke model.

Methods—

We studied 965 patients treated with EVT from a prospective multicenter population-based registry of stroke patients treated with reperfusion therapies in Catalonia, Spain (SONIIA). Three different areas were defined: (A) health areas primarily covered by Comprehensive Stroke Centers, (B) areas primarily covered by local stroke centers located less than hour away from a Comprehensive Stroke Center, and (C) areas primarily covered by local stroke centers located more than hour away from a Comprehensive Stroke Center. We compared the number of EVT×100 000 inhabitants/year and time from stroke onset to groin puncture between groups.

Results—

Baseline characteristics were similar between groups. Throughout the study period, there were significant differences in the population rates of EVT across geographical areas. EVT rates by 100 000 in 2015 were 10.5 in A area, 3.7 in B, and 2.7 in C. Time from symptom onset to groin puncture was 82 minutes longer in group B (312 minutes [245–435]) and 120 minutes longer in group C (350 minutes [284–408]) compared with group A (230 minutes [160–407]; P <0.001).

Conclusions—

Accessibility to EVT from remote areas is hampered by lower rate and longer time to treatment compared with areas covered directly by Comprehensive Stroke Centers.

Ischaemic stroke in patients treated with oral anticoagulants

INTRODUCTION

Cardioembolic stroke is associated with poorer outcomes. Prevention is based on oral anticoagulant (OAC) therapy. Haemorrhage is the main complication of OACs, which are sometimes ineffective.

PATIENTS AND METHODS

We retrospectively reviewed 1014 consecutive patients who suffered an ischaemic stroke between 2011 and 2013, analysing those who were receiving OAC treatment at stroke onset (107 patients in total) with special attention to aetiology, outcomes, and INR value in the acute phase.

RESULTS

The mean age (SD) was 71.9 (10) years. Patients had been treated with OACs for 5.9 (5.5) years; 98.1% of them were being treated for heart disease. INR was <2 in 77 patients (72%), and 30 patients (28%) had an INR≥2. Nine patients (8.4%) had INR values within the therapeutic range. According to TOAST classification criteria, 88.8% of strokes were cardioembolic and 1.9% were atherothrombotic. Anticoagulation therapy was discontinued in 48 patients (44.9%) due to haemorrhagic transformation (24 patients), extensive infarction (23), or endarterectomy (1). Therapy was resumed in 24 patients (50%) after a mean lapse of 36 days. This was not possible in the remaining patients because of death or severe sequelae. New OACs (NOACs) were prescribed to 9 patients (18.7% of all potential candidates). At 3 months, patients with INR>1.7 in the acute phase exhibited better outcomes than patients with INR≤1.7 (mRS 0-2 in 62% vs 30.8%; death in 10% vs 38.4%; P=.0004).

CONCLUSIONS

Some patients taking OACs suffer ischaemic strokes that are usually cardioembolic, especially if INR is below the therapeutic range. OACs can be resumed without complications, and NOACs are still underused. Despite cases in which treatment is ineffective, outcomes are better when INR is above 1.7 at stroke onset.

[Cerebellar infarction: prognosis and complications of vascular territories]

INTRODUCTION

Cerebellar infarction (CI) is uncommon, but may result in severe complications. The aim of our study was to determine the characteristics of patients with CI, as well as their outcomes as regards the territories affected.

PATIENTS AND METHODS

Data were collected from 124 patients admitted to our department during a five-year period, with a radiological diagnosis of CI, and with or without involvement of other brain territories.

RESULTS

The mean age in our series was 65.2 years, with most being male (68.5%). The posterior inferior cerebellar artery (PICA) was the most commonly affected territory at 49.2%, followed by superior cerebellar artery (SCA) at 17.7%, and anterior inferior cerebellar artery (AICA) at 10.5%. There was simultaneous supratentorial involvement in 13.7%, and two or three cerebellar arteries involved in 8.9%. The main aetiology in PICA was atherothrombosis (P=.02). On the other hand, cardio-embolism was the main origin in cases with more than one affected territory (P=.04). No particular aetiology could be found in SCA and AICA. There was haemorrhagic transformation in 29 patients (23.4%), particularly in the PICA and when other territories were involved. There was hydrocephalus in 15 patients (12.1%, 12 of them PICA; P=.02) in 2.9 ± 1.5 days from stroke onset. At discharge, the degree of disability was worse if more than one arterial territory was involved (Rankin ≥ 3, 64% versus 31-36%; P=.05). Four (3.2%) patients died.

CONCLUSIONS

CI is very heterogeneous. Nevertheless, it is noteworthy that PICA infarction is the most frequent type and its aetiology is usually atherothrombotic. Moreover, it is the territory most frequently associated with severe complications, which take place during the first week of the stroke.

AFLPMax: a user-friendly application for computing the optimal number of amplified fragment length polymorphism markers needed in phylogenetic reconstruction

Amplified fragment length polymorphisms (AFLPs) are widely used for phylogenetic inference especially in non-model species. Frequently, trees obtained with other nuclear or mitochondrial markers or with morphological information need additional resolution, increased branch support, or independent data sources (i.e. unlinked loci). In such cases, the use of AFLPs is a quick and cheap option. Computer simulation has shown that dominant AFLP markers lead to less accurate tree topologies than bi-allelic codominant markers such as SNPs, but this difference becomes negligible for shallow trees when using AFLP data sets that include a sufficiently large number of characters. Thus, determining how many AFLP characters are required to recover a given phylogeny is a key issue regarding the appropriateness of AFLPs for phylogenetic reconstruction. Here, we present a user-friendly, java-based graphical interface, AFLPMax, which executes an automatic pipeline of different programs providing the user with the optimal number of AFLP characters needed to recover a given phylogeny with high accuracy and support. Executables for Windows, linux and MacOS X operating systems, source code and user manual are available from: http://webs.uvigo.es/acraaj/AFLPMax.htm.

The relative contribution of band number to phylogenetic accuracy in AFLP data sets

We examined the effect of increasing the number of sampled amplified fragment length polymorphism (AFLP) bands to reconstruct an accurate and well-supported AFLP-based phylogeny. In silico AFLP was performed using simulated DNA sequences evolving along balanced and unbalanced model trees with recent, uniform and ancient radiations and average branch lengths (from the most internal node to the tip) ranging from 0.02 to 0.05 substitutions per site. Trees were estimated by minimum evolution (ME) and maximum parsimony (MP) methods from both DNA sequences and virtual AFLP fingerprints. The comparison of the true tree with the estimated AFLP trees suggests that moderate numbers of AFLP bands are necessary to recover the correct topology with high bootstrap support values (i.e. >70%). Fewer numbers of bands are necessary for shorter tree lengths and for balanced than for unbalanced tree topologies. However, branch length estimation was rather unreliable and did not improve substantially after a certain number of bands were sampled. These results hold for different levels of genome coverage and number of taxa analysed. In silico AFLP using bacterial genomic DNA sequences recovered a well-supported tree topology that mirrored an empirical phylogeny based on a set of 31 orthologous gene sequences when as few as 263 AFLP bands were scored. These results suggest that AFLPs may be an efficient alternative to traditional DNA sequencing for accurate topology reconstruction of shallow trees when not very short ancestral branches exist.

Acute administration of grape seed proanthocyanidin extract modulates energetic metabolism in skeletal muscle and BAT mitochondria

Proanthocyanidin consumption might reduce the risk of developing several pathologies, such as inflammation, oxidative stress and cardiovascular diseases. The beneficial effects of proanthocyanidins are attributed to their antioxidant properties, although they also can modulate gene expression at the transcriptional level. Little is known about the effect of proanthocyanidins on mitochondrial function and energy metabolism. In this context, the objective of this study was to determine the effect of an acute administration of grape seed proanthocyanidin extract (GSPE) on mitochondrial function and energy metabolism. To examine this effect, male Wistar rats fasted for fourteen hours, and then they were orally administered lard oil containing GSPE or were administered lard oil only. Liver, muscle and brown adipose tissue (BAT) were used to study enzymatic activity and gene expression of proteins related to energetic metabolism. Moreover, the gastrocnemius muscle and BAT mitochondria were used to perform high-resolution respirometry. The results showed that, after 5 h, the GSPE administration significantly lowers plasma triglycerides, free fatty acids, glycerol and urea concentrations. In skeletal muscle, GSPE lowers FATP1 mRNA levels and increases mitochondrial oxygen consumption, using pyruvate as the substrate, suggesting a promotion of glycosidic metabolism. Furthermore, GSPE increased the genetic expression of key genes in energy metabolism such as peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (PGC1α), and modulated the enzyme activity of proteins, which are involved in the citric acid cycle and electron transport chain (ETC) in BAT. In conclusion, GSPE affects mainly the skeletal muscle and BAT mitochondria, increasing their oxidative capacity rapidly after acute supplementation.

Semi-quantitative differences in gene transcription profiles between sexes of a marine snail by a new variant of cDNA-AFLP analysis

A variant of the cDNA-AFLP method coupled to an automated sequencer was used to quantify transcripts differentially expressed between sexes of the marine snail Littorina saxatilis. First, we conducted a validation study of the technique using known concentrations of a commercial marker. Second, we analysed six replicates of males and females from a population showing no apparent sexual dimorphism. The results confirm that the method can be properly used within the range of DNA concentrations utilized. In addition, we detected a small percentage of spots (1.8%) differentially expressed between sexes, as expected from a low to moderately sexual dimorphic species.

Interspecies transfer of female mitochondrial DNA is coupled with role-reversals and departure from neutrality in the mussel Mytilus trossulus

Mussels of the genus Mytilus have distinct and highly diverged male and female mitochondrial DNA (mtDNA) genomes with separate routes of inheritance. Previous studies of European populations of Mytilus trossulus demonstrated that 33% of males are heteroplasmic for a second mtDNA genome of increased length and that hybridization with Mytilus edulis does not block mtDNA introgression, in contrast to reports for American populations. Here, we demonstrate that the female mtDNA type of M. edulis has replaced the resident female mtDNA type of European M. trossulus. This is supported by COIII sequence data indicating that the female mtDNA of European M. trossulus is very similar to that of M. edulis and that in phylogenetic trees, the mtDNAs of these two species cluster together but separately from American M. trossulus sequences, the latter not being disturbed by introgressive hybridization. We also provide evidence that the mtDNA genome of increased length found in heteroplasmic males of European M. trossulus derives from a recent partition of an introgressed M. edulis female type into the male route of transmission. Neutrality tests reveal that European populations of M. trossulus display an excess of replacement polymorphism within the female mtDNA type with respect to conspecific American populations, as well as a significant excess of rare variants, of a similar magnitude to those previously reported for the invading European M. edulis mtDNA. Results are consistent with a nearly neutral model of molecular evolution and suggest that selection acting on European M. trossulus mtDNA is largely independent of the nuclear genetic background.

Nonneutral evolution and differential mutation rate of gender-associated mitochondrial DNA lineages in the marine mussel Mytilus

Mussels have two types of mitochondrial DNA (mtDNA). The M type is transmitted paternally, and the F type is transmitted maternally. To test hypotheses of the molecular evolution of both mtDNA genomes, 50 nucleotide sequences were obtained for 396 bp of the COIII gene of European populations of Mytilus edulis and the Atlantic and Mediterranean forms of M. galloprovincialis. Analysis based on the proportion of synonymous and nonsynonymous substitutions indicate that mtDNA is evolving in a non-neutral and complex fashion. Previous studies on American mussels demonstrated that the F genome experiences a higher purifying selection and that the M genome evolves faster. Here we show that these patterns also hold in European populations. However, in contrast to American populations, where an excess of replacement substitution between F and M lineages has been reported, a significant excess of replacement polymorphism within mtDNA lineages is observed in European populations of M. galloprovincialis. European populations also show an excess of replacement polymorphism within the F but not within the M genome with respect to American M. trossulus, as well as a consistent pattern of excess of rare variants in both F and M genomes. These results are consistent with a nearly neutral model of molecular evolution and a recent relaxation of selective constraints on European mtDNA. Levels of diversity are significantly higher for the M than F genome, and the M genome also accumulates synonymous and nonsynonymous substitutions at a higher rate, in contrast with earlier reports where no difference for the synonymous rate was observed. It is suggested that a subtle balance between relaxed selection and a higher mutation rate explains the faster evolutionary rate of the M lineage.

Sex-biased heteroplasmy and mitochondrial DNA inheritance in the mussel Mytilus galloprovincialis Lmk

An exceptional mode of mtDNA inheritance involving separate maternal and paternal transmission routes has been reported recently in the mussel Mytilus edulis. This mode of inheritance provides an explanation for the high levels of heteroplasmy for two highly diverged genomes observed in males of this species. Here we provide evidence for a similar pattern of heteroplasmy in Atlantic and Mediterranean forms of the related mussel M. galloprovincialis. The results support the hypothesis that this mode of mtDNA inheritance has an ancient origin. In addition, the detection of some heteroplasmic females suggests preferential, rather than exclusive, transmission within male and female lines of descent. We also present evidence that the two highly diverged genomes display a parallel split between the Atlantic and Mediterranean forms, consistent with neutral evolution.