Alan Flores

Extending the time window for endovascular procedures according to collateral pial circulation.

Background and Purpose— Good collateral pial circulation (CPC) predicts a favorable outcome in patients undergoing intra-arterial procedures. We aimed to determine if CPC status may be used to decide about pursuing recanalization efforts. Methods— Pial collateral score (0–5) was determined on initial angiogram. We considered good CPC when pial collateral score <3, defined total time of ischemia (TTI) as onset-to-recanalization time, and clinical improvement >4-point decline in admission–discharge National Institutes of Health Stroke Scale. Results— We studied CPC in 61 patients (31 middle cerebral artery, 30 internal carotid artery). Good CPC patients (n=21 [34%]) had lower discharge National Institutes of Health Stroke Scale score (7 versus 21; P=0.02) and smaller infarcts (56 mL versus 238 mL; P<0.001). In poor CPC patients, a receiver operating characteristic curve defined a TTI cutoff point <300 minutes (sensitivity 67%, specificity 75%) that better predicted clinical improvement (TTI <300: 66.7% versus TTI >300: 25%; P=0.05). For good CPC patients, no temporal cutoff point could be defined. Although clinical improvement was similar for patients recanalizing within 300 minutes (poor CPC: 60% versus good CPC: 85.7%; P=0.35), the likelihood of clinical improvement was 3-fold higher after 300 minutes only in good CPC patients (23.1% versus 90.1%; P=0.01). Similarly, infarct volume was reduced 7-fold in good as compared with poor CPC patients only when TTI >300 minutes (TTI <300: poor CPC: 145 mL versus good CPC: 93 mL; P=0.56 and TTI >300: poor CPC: 217 mL versus good CPC: 33 mL; P<0.01). After adjusting for age and baseline National Institutes of Health Stroke Scale score, TTI <300 emerged as an independent predictor of clinical improvement in poor CPC patients (OR, 6.6; 95% CI, 1.01–44.3; P=0.05) but not in good CPC patients. In a logistic regression, good CPC independently predicted clinical improvement after adjusting for TTI, admission National Institutes of Health Stroke Scale score, and age (OR, 12.5; 95% CI, 1.6–74.8; P=0.016). Conclusions— Good CPC predicts better clinical response to intra-arterial treatment beyond 5 hours from onset. In patients with stroke receiving endovascular treatment, identification of good CPC may help physicians when considering pursuing recanalization efforts in late time windows.

Impact of blood pressure changes and course on hematoma growth in acute intracerebral hemorrhage

An association between high blood pressure (BP) in acute intracerebral hemorrhage (ICH) and hematoma growth (HG) has not been clearly demonstrated. Therefore, the impact of BP changes and course on HG and clinical outcome in patients with acute ICH was determined.

Difficult catheter access to the occluded vessel during endovascular treatment of acute ischemic stroke is associated with worse clinical outcome

Background and aim During endovascular procedures for acute ischemic stroke, catheter access to the occluded vessel may be technically difficult or impossible. The aim of this study was to access the impact of difficult catheter access to target the carotid artery on clinical outcome. Methods Anterior circulation stroke patients undergoing transfemoral endovascular procedures where studied. Patients were divided into four groups according to time from groin puncture to target carotid catheterization quartiles. Patients in quartile 4 (Q4) were considered difficult carotid access. We defined several outcome measures: recanalisation (final Thrombolysis in Cerebral Infarction score ≥2a), time from groin puncture to recanalisation and favorable long term outcome (modified Rankin Scale score <3 at 3 months). Results Of 130 patients studied, carotid catheterization was impossible in seven patients (5.1%). These patients had significantly lower rates of recanalization (14.3% vs 80.5%; p<0.01) and favorable outcome (0% vs 36%; p=0.038). Among patients with an accessible carotid artery(n=123), median time from groin puncture to carotid catheterization was 20 min (IQR 10). A negative correlation between time to carotid access and recanalization was observed (r=−0.31; p<0.01). Patients in Q4 (>30 min) had lower rates of recanalization (60.7% vs 82.4%; p=0.02) and a lower favorable outcome (13.6% vs 41.3%; p=0.04). A logistic regression adjusted by age showed that baseline National Institutes of Health Stroke Scale score (OR 0.8; 95% CI: 0.72 to 0.92 p<0.01) and having difficult access (OR 1.3; 95% CI 1.3 to 20.1 p=0.018) independently predicted worse long term outcome. Conclusions Difficult catheter access to target the carotid is common during acute endovascular treatment of stroke patients and is associated with a worse clinical outcome. If transfemoral access appears difficult, alternative access such as direct carotid puncture could be explored.

Endovascular treatment for M2 occlusions in the era of stentrievers: a descriptive multicenter experience

Background Patients with M2 middle cerebral artery (MCA) occlusions are not always considered for endovascular treatment. Objective To study outcomes in patients with M2 occlusion treated with endovascular procedures in the era of stentrievers. Methods We studied patients prospectively included in the SONIIA registry (years 2011–2012)—a mandatory, externally audited registry that monitors the quality of reperfusion therapies in Catalonia in routine practice. Good recanalization was defined as postprocedure Thrombolysis in Cerebral Infarction (TICI) score 2b–3; dramatic recovery as drop in National Institutes of Health Stroke Scale (NIHSS) score >10 points or NIHSS score <2 at 24–36 h; and good outcome as modified Rankin score (mRS) 0–2 at 3 months. A 24 h CT scan determined symptomatic intracranial hemorrhage (SICH) and infarct volume. Results Of 571 patients who received endovascular treatment, 65 (11.4%) presented an M2 occlusion on initial angiogram, preprocedure NIHSS 16 (IQR 6). Mean time from symptom onset to groin puncture was 289±195 min. According to interventionalist preferences 86.2% (n=56) were treated with stentrievers (n=7 in combination with intra-arterial tissue plasminogen activator (tPA), 4.6% (n=3) received intra-arterial tPA only, and 9.2% (n=6) diagnostic angiography only. Good recanalization (78.5%) was associated with dramatic improvement (48% vs 14.8%; p=0.02), smaller infarct volumes (8 vs 82 cc; p=0.01) and better outcome (mRS 0–2: 66.3% vs 30%; p=0.03). SICH (9%) was not associated with treatment modality or device used. After adjusting for age and preprocedure NIHSS, good recanalization emerged as an independent predictor of dramatic improvement (OR=5.9 (95% CI 1.2 to 29.2), p=0.03). Independent predictors of good outcome at 3 months were age ( OR=1.067 (95% CI 1.005 to 1132), p=0.03) and baseline NIHSS ( OR=1.162 (95% CI 1.041 to 1.297), p<0.01). Conclusions Endovascular treatment of M2 MCA occlusion with stentrievers seems safe. Induced recanalization may double the chances of achieving a favorable outcome, especially for patients with moderate or severe deficit.

Trevo versus solitaire a head-to-head comparison between two heavy weights of clot retrieval.

Recent reports have indicated that mechanical thrombectomy may have potential to treat acute ischemic stroke. However, few comparative studies of neurothrombectomy devices are reported. This study aims to compare the safety and effectiveness of two retrievable stent systems in acute ischemic stroke patients.

Trevo System: Single‐Center Experience with a Novel Mechanical Thrombectomy Device

Recent reports have indicated that mechanical thrombectomy may have the potential to treat acute ischemic stroke. This study aims to describe the safety and effectiveness of Trevo Retriever, using Stentriever technology, in revascularization of patients with acute ischemic stroke.

Age-adjusted infarct volume threshold for good outcome after endovascular treatment

Background and purpose Infarct volume and age are strong predictors of outcome in patients with stroke. We aimed to determine the impact of infarct volume on outcome according to age. Methods Consecutive patients with acute stroke with documented internal carotid artery/middle cerebral artery occlusion who underwent endovascular procedures were studied. Patients were categorized in three age groups: <70 years (G1), 70–79 years (G2), ≥80 years (G3). The Alberta Stroke Program Early CT score (ASPECTS) was graded on initial CT. Time of successful recanalization (Thrombolysis In Cerebral Infarct (TICI) ≥2b )and good outcome at 3 months (modified Rankin Scale score ≤2) were recorded. Infarct volume was measured on the 24 h control CT. Results A total of 214 patients were studied (G1: 68; G2: 74; G3: 72). For all patients the mean infarct volume was 94.7±127 mL; 35.6% had a good outcome. We observed larger infarct volumes in patients with a bad outcome in each age group (G1: 22 vs 182 mL, p<0.01/G2: 22 vs 164 mL, p<0.01/G3: 7.6 vs 132 mL, p<0.01). However, the target cut-off infarct volume that better predicted a good outcome decreased as age increased: G1: 49 mL (sensitivity 80%, specificity 92.6%); G2: 32.5 mL (sensitivity 80%, specificity 81%); G3: 15.2 mL (sensitivity 81.3%, specificity 86.7%). Overall, after adjusting for age, occlusion location, baseline NIH Stroke Scale score and infarct volume, the only predictor of a good outcome was achieving a final infarct volume less than the age-adjusted target (OR 5.5, 95% CI 1.6 to 18.8; p<0.01). The probability of achieving an infarct volume less than the age-adjusted target decreased according to baseline ASPECTS, time and degree of recanalization. Conclusions Age-adjusted infarct size might represent a powerful surrogate marker of stroke outcome and further refine the predictive accuracy of infarct volume on prognosis in patients with stroke undergoing endovascular treatment. This information may be used in the design of new trials to individualize selection criteria for different age groups.

VAP-1/SSAO Plasma Activity and Brain Expression in Human Hemorrhagic Stroke

Background: Vascular adhesion protein-1 (VAP-1) is a cell surface and circulating enzyme that belongs to the semicarbazide-sensitive amine oxidase (SSAO) family, which oxidatively deaminates primary amines and is implicated in leukocyte extravasation. Our aim was to investigate the alteration of soluble VAP-1/SSAO activity in plasma samples after acute intracerebral hemorrhage (ICH) and its presence in human ICH brain tissue. Methods: VAP-1/SSAO activity was determined in plasma of 66 ICH patients and 58 healthy controls. In addition, we assessed the expression of VAP-1/SSAO in postmortem brain tissue from hemorrhagic stroke patients by Western blot and immunohistochemistry. Results: We observed significantly higher levels of plasma VAP-1/SSAO activity in patients with ICH compared to matched elderly controls (p = 0.001). Plasma VAP-1/SSAO activity <2.7 pmol/min·mg and baseline ICH volume <17 ml were independent predictors of neurological improvement after 48 h (OR 6.8, 95% CI 1.14–41.67, p = 0.035, and OR 10.64, 95% CI 1.1–100, p = 0.041, respectively), after adjustment for baseline stroke severity. We also found that membrane-bound VAP-1/SSAO levels were lower in the perihematoma region than in the corresponding contralateral brain areas of patients deceased due to ICH (p = 0.024). Conclusions: Our data demonstrate that plasma VAP-1/SSAO activity is increased in ICH and predicts neurological outcome, suggesting a possible contribution of the soluble protein in secondary brain damage. Furthermore, anti-VAP-1/SSAO strategies might be a promising approach to prevent neurological worsening following ICH.

Impact of Time to Treatment on Tissue-Type Plasminogen Activator–Induced Recanalization in Acute Ischemic Stroke

Background and Purpose— Although tissue-type plasminogen activator (tPA) efficacy depends on time, it is unknown whether its effect on recanalization is time dependent. Information about likelihood of successful recanalization as a function of time to treatment may improve patient selection for advanced reperfusion strategies. We aimed to identify the impact of time to treatment on tPA-induced recanalization in patients with acute ischemic stroke. Methods— Consecutive patients with intracranial acute occlusion treated with intravenous tPA underwent transcranial Doppler examination before and 1 hour after tPA administration. Patients were categorized according to occlusion localization in proximal and distal occlusion. Sequential analysis of recanalization according to time to treatment was performed for every 30-minute cutoff point. Results— Overall (n=508), 54.3% had proximal and 45.7% had distal occlusion. Median time to treatment was 171.4±61.9 minutes, and 5.9% were treated >270 minutes. Recanalization occurred in 36.1% of patients. There was no linear association between time to treatment and time to recanalization, but sequential analysis showed that patients treated >270 minutes had a lower recanalization rate. Lower National Institutes of Health Stroke Scale score on admission (odds ratio [OR], 0.305; 95% confidence interval [CI], 0.1–0.933) and time to treatment ⩽270 minutes (OR, 0.995; 95% CI, 0.99–0.999) emerged as independent predictors of recanalization. In patients with proximal occlusion, 41.8% recanalized. Time to treatment >90 minutes was associated with lower recanalization rate. However, only younger age (OR, 0.975; 95% CI, 0.952–0.999) and lower baseline National Institutes of Health Stroke Scale score (OR, 0.921; 95% CI, 0.855–0.993) independently predicted recanalization. In distal occlusion patients, male sex was the only independent predictor of recanalization (OR, 0.416; 95% CI, 0.195–0.887). None recanalized >270 minutes. Conclusions— The effect of tPA on recanalization may decrease over time. Treatment >270 minutes predicted lack of recanalization, especially in distal occlusions.

Left Atria Strain Is a Surrogate Marker for Detection of Atrial Fibrillation in Cryptogenic Strokes

After complete diagnostic workup, a quarter of ischemic strokes are regarded as undetermined pathogenesis at discharge with a substantial rate of mortality in some cases.1 Paroxysmal atrial fibrillation (PAF) is the most frequent occult cause resulting in significant morbidity and costs when is under diagnosed.2 Recent studies have shown that extending the cardiac monitoring duration with subcutaneous implantable monitors and selecting patients for prolonged monitoring significantly increased the PAF detection in ischemic strokes.3 The left atria volume (LAv) has been used to assess the left atrial function. Nevertheless, the left atria dimension is predictive of stroke but become nonsignificant after adjustment for the older age.4 The left atria function can be also obtained by the analysis of the left atria walls deformation, also called strain of the left atria. The speckle tracking is an echocardiographic technique that uses standard B-mode images for the analysis of the acoustic backscatter generated by the ultrasound beam. The changes between speckles are assumed to represent the strain.5 The published intraobserver and interobserver variability of left atria strain (LAS) is 7.8%, and 8.9%, respectively.6 The LAS profile has been previously described in patients with PAF and in correlation with CHADS2 score (hypertension >140/90 mm Hg, age ≥75, diabetes, prior stroke),7 but it has never been studied in cryptogenic ischemic strokes. We aimed to describe the left atria functionality assessed by LAS parameter in cryptogenic strokes to improve the detection of occult PAF. With the purpose to obtain the best LAS cutoff point to differentiate patients with and without PAF, we planned the comparison as a case–control study. Accordingly, the selection of patients without PAF (non-PAF group) was made considering consecutive patients with cryptogenic stroke after complete workup evaluation with no PAF episodes in 3-year cardiac monitoring with Holter …