The efficacy and safety of high-dose statins in acute phase of ischemic stroke and transient ischemic attack: a systematic review

Novel Therapeutic Approaches to Prevent Atherothrombotic Ischemic Stroke in Patients with Carotid Atherosclerosis

Atherothrombotic stroke represents approximately 20% of all ischemic strokes. It is caused by large-artery atherosclerosis, mostly in the internal carotid artery, and it is associated with a high risk of early recurrence. After an ischemic stroke, tissue plasminogen activator is used in clinical practice, although it is not possible in all patients. In severe clinical situations, such as high carotid stenosis (≥70%), revascularization by carotid endarterectomy or by stent placement is carried out to avoid recurrences. In stroke prevention, the pharmacological recommendations are based on antithrombotic, lipid-lowering, and antihypertensive therapy. Inflammation is a promising target in stroke prevention, particularly in ischemic strokes associated with atherosclerosis. However, the use of anti-inflammatory strategies has been scarcely studied. No clinical trials are clearly successful and most preclinical studies are focused on protection after a stroke. The present review describes novel therapies addressed to counteract inflammation in the prevention of the first-ever or recurrent stroke. The putative clinical use of broad-spectrum and specific anti-inflammatory drugs, such as monoclonal antibodies and microRNAs (miRNAs) as regulators of atherosclerosis, will be outlined. Further studies are necessary to ascertain which patients may benefit from anti-inflammatory agents and how.

Pathophysiology and Optimal Treatment of Intracranial Branch Atheromatous Disease

Intracranial branch atheromatous disease (BAD) is a pathological condition characterized by the occlusion of a relatively large perforating branch (700-800 µm) near the orifice of a parent artery due to atherosclerotic plaque-based thrombus (microatheroma). BAD is refractory to treatment and follows a course of progressive exacerbation, especially motor paralysis. Uniform treatment for common atherothrombotic cerebral infarction or lacunar infarction does not prevent the progressive exacerbation of BAD, and consequently affects functional prognosis. To date, various combinations of treatments have been investigated and proposed to attenuate the worsening symptoms of BAD. However, no therapy with established efficacy is yet available for BAD. Since it is the most difficult condition to treat in the area of cerebral infarction, the establishment of optimal treatment methods for BAD is keenly awaited. This review presents an overview of the acute treatments available for BAD and discusses the prospects for optimal treatment.

Relationship between the stroke mechanism of symptomatic middle cerebral artery atherosclerotic diseases and culprit plaques based on high-resolution vessel wall imaging

Purpose

For patients with symptomatic middle cerebral artery (MCA) atherosclerotic stenosis, identifying the potential stroke mechanisms may contribute to secondary prevention. The purpose of the study is to explore the relationship between stroke mechanisms and the characteristics of culprit plaques in patients with atherosclerotic ischemic stroke in the M1 segment of the middle cerebral artery (MCA) based on high-resolution vessel wall imaging (HR-VWI).

Methods

We recruited 61 patients with acute ischemic stroke due to MCA atherosclerotic stenosis from Shenzhen Bao'an District People's Hospital. According to prespecified criteria based on infarct topography and magnetic resonance angiography, possible stroke mechanisms were divided into parent artery atherosclerosis occluding penetrating artery (P), artery-to-artery embolism (A), hypoperfusion (H), and mixed mechanisms (M). The correlation between the characteristics of MCA M1 culprit plaque and different stroke mechanisms was analyzed using HR-VWI. The indicators included plaque surface irregularity, T1 hyperintensity, location, plaque burden (PB), remodeling index (RI), enhancement rate, and stenosis rate.

Results

Parental artery atherosclerosis occluding penetrating artery was the most common mechanism (37.7%). The proposed criteria showed substantial to excellent interrater reproducibility (κ, 0.728; 0.593–0.863). Compared with the P group, the surface irregularity, T1 hyperintensity, and obvious enhancement of the culprit plaque in the A group were more common (p < 0.0125). Compared with the other stroke mechanisms, positive remodeling of culprit plaques was more common (p < 0.0125), the RI was greater (p < 0.05), and the PB was the smallest (p < 0.05) in the P group. The enhancement ratio (ER) was smaller in the P group (p < 0.05). Compared with the A group, T1 hyperintensity of the culprit plaque was more common in the H group (p < 0.0125), and the stenosis rate was greater (p < 0.05). After adjustment for clinical demographic factors in the binary logistic regression analysis, the enhancement level (odds ratio [OR] 0.213, 95% CI (0.05–0.91), p = 0.037) and PB of culprit plaque (OR 0, 95% CI (0–0.477), p = 0.034) were negatively associated with P groups.

Conclusion

The culprit plaque characteristics of patients with symptomatic MCA atherosclerotic in different stroke mechanisms may be evaluated using HR-VWI. The plaque characteristics of different stroke mechanisms may have clinical value for the selection of treatment strategies and prevention of stroke recurrence.

Clinical trial registration

Identifier: ChiCTR1900028533.

Comparative Efficacy of Different Repetitive Transcranial Magnetic Stimulation Protocols for Stroke: A Network Meta-Analysis

Background

Although repetitive transcranial magnetic stimulation (rTMS) has been proven to be effective in the upper limb motor function and activities of daily living (ADL), the therapeutic effects of different stimulation protocols have not been effectively compared. To fill this gap, this study carried out the comparison of the upper limb motor function and ADL performance of patients with stroke through a network meta-analysis.

Methods

Randomized controlled trials (RCTs) on the rTMS therapy for stroke were searched from various databases, including PubMed, web of science, Embase, Cochrane Library, ProQuest, Wanfang database, the China National Knowledge Infrastructure (CNKI), and VIP information (www.cqvip.com). The retrieval period was from the establishment of the database to January 2021. Meanwhile, five independent researchers were responsible for the study selection, data extraction, and quality evaluation. The outcome measures included Upper Extremity Fugl-Meyer Assessment (UE-FMA), Wolf Motor Function Test (WMFT), Modified Barthel Index (MBI), the National Institute of Health stroke scale (NIHSS), and adverse reactions. The Gemtc 0.14.3 software based on the Bayesian model framework was used for network meta-analysis, and funnel plots and network diagram plots were conducted using Stata14.0 software.

Results

Ninety-five studies and 5,016 patients were included ultimately. The intervention measures included were as follows: placebo, intermittent theta-burst stimulation (ITBS), continuous theta-burst stimulation (CTBS),1 Hz rTMS,3–5 Hz rTMS, and ≥10 Hz rTMS. The results of the network meta-analysis show that different rTMS protocols were superior to placebo in terms of UE-FMA, NIHSS, and MBI outcomes. In the probability ranking results, ≥10 Hz rTMS ranked first in UE-FMA, WMFT, and MBI. For the NIHSS outcome, the ITBS ranked first and 1 Hz rTMS ranked the second. The subgroup analyses of UE-FMA showed that ≥10 Hz rTMS was the best stimulation protocol for mild stroke, severe stroke, and the convalescent phase, as well as ITBS was for acute and subacute phases. In addition, it was reported in 13 included studies that only a few patients suffered from adverse reactions, such as headache, nausea, and emesis.

Conclusion

Overall, ≥10 Hz rTMS may be the best stimulation protocol for improving the upper limb motor function and ADL performance in patients with stroke. Considering the impact of stroke severity and phase on the upper limb motor function, ≥10 Hz rTMS may be the preferred stimulation protocol for mild stroke, severe stroke, and for the convalescent phase, and ITBS for acute and subacute phases.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier [CRD42020212253].

Statin and dual antiplatelet therapy for the prevention of early neurological deterioration and recurrent stroke in branch atheromatous disease: a protocol for a prospective single-arm study using a historical control for comparison

INTRODUCTION

Branch atheromatous disease (BAD) contributes to small-vessel occlusion in cases of occlusion or stenosis of large calibre penetrating arteries, and it is associated with a higher possibility of early neurological deterioration (END) and recurrent stroke in acute ischaemic stroke. As the pathology of BAD is due to atherosclerosis, we postulate that early intensive medical treatment with dual antiplatelet therapy (DAPT) and high-intensity statins may prevent END and recurrent stroke in acute small subcortical infarction caused by BAD.

METHODS AND ANALYSIS

In this prospective, single-centre, open-label, non-randomised, single-arm study using a historical control, we will compare early DAPT and high-intensity statin treatment with a historical control group of patients with BAD who were treated with single antiplatelet therapy without high-intensity statin treatment. Patients will be eligible for enrolment if they are admitted for acute ischaemic stroke within 24 hours, have a National Institutes of Health Stroke Scale (NIHSS) score of 1-8 and are diagnosed with BAD by MRI. Patients will take aspirin, clopidogrel and high-intensity statins (atorvastatin or rosuvastatin) within 24 hours of stroke onset, followed by aspirin or clopidogrel alone from day 22. The primary endpoint is the percentage of patients who develop END within 7 days of stroke onset (defined as an increase in the NIHSS score ≥2 points) and recurrent stroke within 30 days. The total sample sizes will be 138 for the intervention group and 277 for the control group. A historical control group will be drawn from previous prospective observation studies.

ETHICS AND DISSEMINATION

The protocol of this study has been approved by the Institutional Review Board of Chang Gung Memorial Hospital (202001386A3). All participants will have to sign and date an informed consent form. The findings arising from this study will be disseminated in peer-reviewed journals and academic conferences.

TRIAL REGISTRATION NUMBER

NCT04824911.

Statin use and mortality in atrial fibrillation: A systematic review and meta-analysis of 100,287 patients

Statins are effective for reducing cardiovascular disease in patients at risk or with cardiovascular disease. The benefit of statin therapy on adverse cardiovascular outcomes in patients with non-valvular atrial fibrillation (AF) is not clear. We performed a systematic review and meta-analysis of studies retrieved from MEDLINE via PubMed and Cochrane (CENTRAL) database of studies investigating the efficacy of statins in AF patients. The principal endpoint was all-cause mortality. Other endpoints were cardiovascular mortality, ischemic stroke, composite endpoints and any bleeding. We included 14 studies (2 post-hoc analysis of randomized clinical trials, 8 prospective and 4 retrospective) with 100,287 AF patients, of whom 23,228 were on statins. The pooled hazard ratio (HR) for all-cause mortality was 0.59 (95 % Confidence Interval [CI] 0.54-0.65). This association was consistent by aging, sex and prevalent cardiovascular or cerebrovascular disease. and the beneficial effect was evident already after 12 months of therapy. The absolute risk reduction for all-cause mortality in patients treated with statins was 10 % (95 % CI 9-10). The pooled HR for statins against cardiovascular mortality was 0.75 (95 % CI 0.58-0.96). No association was found with other secondary endpoints. Regarding bleeding events, the pooled HR for statin use was 0.60 (95 % CI 0.48-0.76). Our meta-analysis shows that in AF patients, statin therapy was associated with a reduction in all-cause and cardiovascular mortality are reduced by 41 % and 25 %, respectively. Randomized clinical trials in AF patients are necessary, as well as clarity on AF-specific LDL cholesterol targets.

Premorbid Use of Statin and Outcome of Acute Ischemic Stroke After Intravenous Thrombolysis: A Meta-Analysis

Background: The association between the premorbid use of statin and the early outcomes of acute ischemic stroke (AIS) after intravenous thrombolysis (IVT) remains uncertain. We performed a meta-analysis of observational studies to evaluate the influence of the premorbid use of statin on functional outcome and symptomatic intracranial hemorrhage (SIH) in AIS after IVT. Methods: Relevant studies were identified by search of PubMed, Embase, and Cochrane's Library databases. Only studies with multivariate analyses were included. A random-effect model, incorporating inter-study heterogeneity, was used to pool the results. Results: Twenty observational studies with 20,752 AIS patients who were treated with IVT were included. The pooled results showed that the premorbid use of statin was not associated with improved 3-month favorable functional outcome [odds ratio (OR): 1.05, 95% confidence interval (CI): 0.87-1.26, p = 0.60, I ² = 52%), 3-month functional independence (OR: 1.13, 95% CI: 0.96-1.33, p = 0.15, I ² = 52%), or 3-month mortality (OR: 1.12, 95% CI: 0.94-1.34, p = 0.20, I ² = 20%). Moreover, the premorbid use of statin was associated with an increased risk of SIH in AIS after IVT (OR: 1.48, 95% CI: 1.12-1.95, p = 0.006, I ² = 60%). Subgroup analyses according to study design, adjustment of baseline low-density lipoprotein cholesterol, and definitions of SIH showed consistent results (p-values for subgroup difference all >0.05). Conclusions: The premorbid use of statin is not associated with improved functional outcomes or mortality but is associated with a higher risk of SIH in AIS patients after IVT.

Cholesterol reducer and thrombolytic therapy in acute ischemic stroke patients

BACKGROUND

Specific clinical risk factors may contribute to improving or worsening neurological functions in acute ischemic stroke (AIS) patients pre-treated with a combined cholesterol reducer and recombinant tissue plasminogen activator (rtPA) therapy. In this study, clinical risk factors associated with good or poor presenting neurological symptoms in ischemic stroke patients with prior cholesterol reducer use, specifically a statin and rtPA therapy was investigated.

METHODS

Retrospective data for baseline clinical and demographic data for patients with AIS taking cholesterol reducers prior to rtPA treatment from January 2010 to June 2016 in a regional stroke center was analyzed. Improving (NIHSS score ≤ 7) or worsening (NIHSS score > 7) of neurologic functions were the determined measures of treatment outcome. Multivariate logistic regression models identified demographic and clinical factors associated with worsening or improving neurologic functions.

RESULTS

Adjusted multivariate analysis showed that in an AIS population with a combined rtPA and cholesterol reducer medication history, increasing age (OR = 1.032, 95% CI, 1.015-1.048, P < 0.001) and atrial fibrillation (OR = 1.859, 95% CI, 1.098-3.149, P = 0.021) demonstrated a likely association with worsening neurologic functions, while direct admission (OR = 0.411, 95% CI, 0.246-0.686, P = 0.001) and being Caucasian (OR = 0.496, 95% CI, 0.297-0.827, P = 0.007) showed an association with improving or progressing neurologic functions.

CONCLUSION

A prior cholesterol reducer, namely a statin, plus rtPA combination may be associated with worsening neurological function for elderly AIS patients with atrial fibrillation, while Caucasians directly admitted to a neurology unit are more likely to show an association with progress or improvements in neurologic functions. While combining statin with rtPA treatment may facilitate worsening neurologic functions in elderly AIS patients with atrial fibrillation, they should not be denied of this therapy. The decision to combine statin and rtPA for AIS patients with atrial fibrillation can be done after clinical stabilization following appropriate clinical management.

Statin Therapy in Ischemic Stroke Models: A Meta-Analysis

Statins, drugs known for lipid lowering capabilities and reduction of cardiovascular disease, have demonstrated neuroprotective effects following ischemic stroke in retrospective clinical and animal studies. However, dosing (methods, time, type of statin, and quantity) varies across studies, limiting the clinical applicability of these findings. Furthermore, a comprehensive review of statins in edema and blood-brain barrier (BBB) breakdown is needed to provide insight on diverse, less explored neuroprotective effects. In the present study, we conduct a meta-analysis of publications evaluating statin administration in animal models of ischemic stroke. We review statins' most effective dosing regimen in four outcomes-infarct, edema, BBB breakdown, and functional outcome-to characterize several parameters of benefit associated with statin administration. A search term was constructed to identify experimental murine studies exploring statin use after transient middle cerebral artery occlusion (tMCAO) in PubMed, Web of Science, and Embase. Extracted data included statin type, dose, time and method of administration, and the four predetermined outcomes (functional outcome, edema, BBB breakdown, and infarction). A meta-analysis and stratified meta-regression were conducted using the standardized mean difference (SMD) method for continuous measurements. Included publications were assessed for bias using SYRCLE's RoB tool for animal studies. A total of 24 studies were included. Statin administration significantly reduced infarct volume (p < 0.0001), edema volume (p < 0.002), and neurological deficit (p < 0.0001). Simvastatin and pravastatin were most effective in reducing infarct volume when compared with atorvastatin (p = 0.0475, p = 0.0004) and rosuvastatin (p = 0.0036, p < 0.0001). Pravastatin outperformed all others in functional outcome. Subcutaneous (SC) injection was most effective in all outcomes. Statin therapy reduced BBB breakdown according to our systematic review. Mean study quality was 4.6/10. While statin therapy evidently improves neurological outcome following ischemic stroke, this analysis adds to our understanding of dosing and statins' effects on edema and BBB breakdown. These findings will aid the design of future studies investigating statin use and have larger implications for the clinical care of ischemic stroke patients.

Does statin increase the risk of intracerebral hemorrhage in stroke survivors? A meta-analysis and trial sequential analysis

BACKGROUND

It remains debatable whether statin increases the risk of intracerebral hemorrhage (ICH) in poststroke patients.

METHODS

We systematically searched PubMed, EMBASE, and CENTRAL for randomized controlled trials. Trial sequential analysis (TSA) was conducted to assess the reliability and conclusiveness of the available evidence in the meta-analysis. To evaluate the overall effectiveness, the net composite endpoints were derived by totaling ischemic stroke, hemorrhagic stroke, transient ischemic attack (TIA), myocardial infarction, and cardiovascular mortality.

RESULTS

A total of 17 trials with 11,576 subjects with previous ischemic stroke, TIA, or ICH were included, in which statin therapy increased the risk of hemorrhagic stroke (risk ratio [RR], 1.42; 95% confidence interval [CI], 1.07-1.87), but reduced the risk of ischemic stroke (RR, 0.85; 95% CI, 0.75-0.95). For the net composite endpoints, statin therapy was associated with a 17% risk reduction (95% CI, 12-21%; number needed to treat = 6). With a control event rate 2% and RR increase 40%, the TSA suggested a conclusive signal of an increased risk of hemorrhagic stroke in stroke survivors taking statin. However, with the sensitivity analysis by changing assumptions, the conclusions about hemorrhagic stroke risk were less robust.

CONCLUSIONS

Statin therapy in poststroke patients increased the risk of hemorrhagic stroke but effectively reduced ischemic stroke risk. Weighing the benefits and potential harms, statin has an overall beneficial effect in patients with previous stroke or TIA. However, more studies are required to investigate the conclusiveness of the increased hemorrhagic stroke risk revealed in our study.

A Novel Neuroimaging Model to Predict Early Neurological Deterioration After Acute Ischemic Stroke

Objective:

In acute ischemic stroke, early neurological deterioration (END) may occur in up to one-third of patients. However, there is still no satisfying or comprehensive predictive model for all the stroke subtypes. We propose a practical model to predict END using magnetic resonance imaging (MRI).

Method:

Patients with anterior circulation infarct were recruited and they underwent an MRI within 24 hours of stroke onset. END was defined as an elevation of ≥2 points on the National Institute of Health Stroke Scale (NIHSS) within 72 hours of stroke onset. We examined the relationships of END to individual END models, including: A, infarct swelling; B, small subcortical infarct; C, mis-match; and D, recurrence.

Results:

There were 163 patients recruited and 43 (26.4%) of them had END. The END models A, B and C significantly predicted END respectively after adjusting for confounding factors (p=0.022, p=0.007 and p<0.001 respectively). In END model D, we examined all imaging predictors of Recur-rence Risk Estimator (RRE) individually and only the “multiple acute infarcts” pattern was signifi-cantly associated with END (p=0.032). When applying END models A, B, C and D, they success-fully predicted END (p<0.001; odds ratio: 17.5[95% confidence interval: 5.1–60.8]), with 93.0% sensitivity, 60.0% specificity, 45.5% positive predictive value and 96.0% negative predictive value.

Conclusion:

The results demonstrate that the proposed model could predict END in all stroke sub-types of anterior circulation infarction. It provides a practical model for clinical physicians to select high-risk patients for more aggressive treatment to prevent END.

Comparison of statins for secondary prevention in patients with ischemic stroke or transient ischemic attack: a systematic review and network meta-analysis

BACKGROUND

Statins may prevent recurrent ischemic events after ischemic stroke. Determining which statin to use remains controversial. We aimed to summarize the evidence for the use of statins in secondary prevention for patients with ischemic stroke by comparing benefits and harms of various statins.

METHODS

We searched for randomized controlled trials (RCTs) assessing statins in patients with ischemic stroke or transient ischemic attack (TIA) in MEDLINE, EMBASE, and CENTRAL up to July 2017. Two authors extracted data and appraised risks of bias. We performed pairwise meta-analyses and trial sequential analyses (TSA) to compare statins versus placebo/no statin, and network meta-analyses using frequentist random-effects models to compare statins through indirect evidence. We used GRADE to rate the overall certainty of evidence. Primary outcomes were all-cause mortality and all strokes. Secondary outcomes were different types of strokes, cardiovascular events, and adverse events.

RESULTS

We identified nine trials (10,741 patients). No head-to-head RCTs were found. The median follow-up period was 2.5 years. Statins did not seem to modify all stroke and all-cause mortality outcomes; they were associated with a decreased risk of ischemic stroke (odds ratio, OR, 0.81 [95% CI, 0.70 to 0.93]; absolute risk difference, ARD, - 1.6% [95% CI, - 2.6 to - 0.6%]), ischemic stroke or TIA (OR, 0.75 [95% CI, 0.64 to 0.87]; ARD, - 4.2% [95% CI, - 6.2 to - 2.1%]), and cardiovascular event (OR, 0.75 [95% CI, 0.69 to 0.83]; ARD, - 5.4% [95% CI, - 6.8 to - 3.6%]), and did not seem to modify rhabdomyolysis, myalgia, or rise in creatine kinase. In the comparison of different statins, moderate- to high-quality evidence indicated that differences between pharmaceutical products seemed modest, with high doses (e.g., atorvastatin 80 mg/day and simvastatin 40 mg/day) associated with the greatest benefits. TSA excluded random error as a cause of the findings for ischemic stroke and cardiovascular event outcomes. Evidence for increased risk of hemorrhagic stroke was sensitive to the exclusion of the SPARCL trial.

CONCLUSIONS

Evidence strongly suggests that statins are associated with a reduction in the absolute risk of ischemic strokes and cardiovascular events. Differences in effects among statins were modest, signaling potential therapeutic equivalence.

TRIAL REGISTRATION

PROSPERO CRD42018079112.

HMG-CoA Reductase Inhibitors Attenuate Neuronal Damage by Suppressing Oxygen Glucose Deprivation-Induced Activated Microglial Cells

Ischemic stroke is usually followed by inflammatory responses mediated by microglia. However, the effect of statins on directly preventing posthypoxia microglia inflammatory factors to prevent injury to surrounding healthy neurons is unclear. Atorvastatin and rosuvastatin, which have different physical properties regarding their lipid and water solubility, are the most common HMG-CoA reductase inhibitors (statins) and might directly block posthypoxia microglia inflammatory factors to prevent injury to surrounding neurons. Neuronal damage and microglial activation of the peri-infarct areas were investigated by Western blotting and immunofluorescence after 24 hours in a middle cerebral artery occlusion (MCAO) rat model. The decrease in neurons was in accordance with the increase in microglia, which could be reversed by both atorvastatin and rosuvastatin. The effects of statins on blocking secretions from posthypoxia microglia and reducing the secondary damage to surrounding normal neurons were studied in a coculture system in vitro. BV2 microglia were cultured under oxygen glucose deprivation (OGD) for 3 hours and then cocultured following reperfusion for 24 hours in the upper wells of transwell plates with primary neurons being cultured in the bottom wells. Inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and cyclooxygenase-2 (COX2), which are activated by the nuclear factor-kappa B (NF-κB) signaling pathway in OGD-induced BV2 microglia, promoted decreased release of the anti-inflammatory cytokine IL-10 and apoptosis of neurons in the coculture systems according to ELISA and Western blotting. However, pretreatment with atorvastatin or rosuvastatin significantly reduced neuronal death, synaptic injury, and amyloid-beta (Aβ) accumulation, which might lead to increased low-density lipoprotein receptors (LDLRs) in BV2 microglia. We concluded that the proinflammatory mediators released from postischemia damage could cause damage to surrounding normal neurons, while HMG-CoA reductase inhibitors prevented neuronal apoptosis and synaptic injury by inactivating microglia through blocking the NF-κB signaling pathway.

Statins for the Primary Prevention of Coronary Heart Disease

Object

The purpose of this study was to fully assess the role of statins in the primary prevention of coronary heart disease (CHD).

Methods

We searched six databases (PubMed, the Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang Database, and Chinese Scientific Journal Database) to identify relevant randomized controlled trials (RCTs) from inception to 31 October 2017. Two review authors independently assessed the methodological quality and analysed the data using Rev Man 5.3 software. Risk ratios and 95% confidence intervals (95% CI) were pooled using fixed/random-effects models. Funnel plots and Begg's test were conducted to assess publication bias. The quality of the evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

Results

Sixteen RCTs with 69159 participants were included in this review. Statins can effectively decrease the occurrence of angina (RR=0.70, 95% CI: 0.58~0.85, I² =0%), nonfatal myocardial infarction (MI) (RR=0.60, 95% CI: 0.51~0.69, I² =14%), fatal MI (RR=0.49, 95% CI: 0.24~0.98, I² =0%), any MI (RR=0.53, 95% CI: 0.42~0.67, I² =0%), any coronary heart events (RR=0.73, 95% CI: 0.68~0.78, I²=0%), coronary revascularization (RR=0.66, 95% CI: 0.55~0.78, I² = 0%), and any cardiovascular events (RR=0.77, 95% CI: 0.72~82, I² = 0%). However, based on the current evidence, there were no significant differences in CHD deaths (RR=0.82, 95% CI: 0.66~1.02, I²=0%) and all-cause mortality (RR=0.88, 95% CI: 0.76 ~1.01, I² =58%) between the two groups. Additionally, statins were more likely to result in diabetes (RR=1.21, 95% CI: 1.05~1.39, I² =0%). There was no evidence of publication biases, and the quality of the evidence was considered moderate.

Conclusion

Statins seemed to be beneficial for the primary prevention of CHDs but have no effect on CHD death and all-cause mortality.

Low flow in the left atrial appendage assessed by transesophageal echocardiography is associated with increased stroke severity-Results of a single-center cross-sectional study

BACKGROUND

About 25% of strokes are thought to be cryptogenic. There is growing evidence that most of these cryptogenic strokes are thromboembolic and caused by an undetected atrial fibrillation. Measured slow flow in the left atrial appendage has been proposed to be an indicator for the thromboembolic risk since it is possibly associated with undetected atrial fibrillation.

METHODS

We evaluated all patients (n = 909; mean of 62 years, 39% female) admitted with an ischemic stroke (84%) or transient ischemic attack to our university medical center who underwent transesophageal echocardiography examination 2012-2014. Baseline characteristics, cardio-/neurovascular risk factors, electrocardiogram monitoring data, National Institute of Health Stroke Scale values, the localization of the stroke, as well as transesophageal echocardiography findings were analyzed.

RESULTS

Stroke severity measured by the National Institute of Health Stroke Scale in patients with a low flow in the left atrial appendage was significantly higher than in patients without left atrial appendage low flow (p < 0.001). There was a threshold phenomenon in flow velocity at about 60 cm/s above which no significant change in National Institute of Health Stroke Scale values could be observed. These patients were significantly different concerning incidence of heart failure (10.6% vs. 2.3%; p < 0.001) and atrial fibrillation (32.2% vs. 8.8%; p < 0.001). However, threshold phenomenon of left atrial appendage flow was unchanged when excluding atrial fibrillation and heart failure patients.

CONCLUSIONS

A low flow in the left atrial appendage was associated with clinically elevated stroke severity and could be indicated as an independent stroke risk factor. Further prospective studies are warranted to evaluate beneficial effects of therapeutic options in these patients also in the assumed absence of atrial fibrillation.

Recent advances in the management of transient ischemic attacks

Significant advances in our understanding of transient ischemic attack (TIA) have taken place since it was first recognized as a major risk factor for stroke during the late 1950's. Recently, numerous studies have consistently shown that patients who have experienced a TIA constitute a heterogeneous population, with multiple causative factors as well as an average 5-10% risk of suffering a stroke during the 30 days that follow the index event. These two attributes have driven the most important changes in the management of TIA patients over the last decade, with particular attention paid to effective stroke risk stratification, efficient and comprehensive diagnostic assessment, and a sound therapeutic approach, destined to reduce the risk of subsequent ischemic stroke. This review is an outline of these changes, including a discussion of their advantages and disadvantages, and references to how new trends are likely to influence the future care of these patients.