Systematic Review on Botulinum Toxin Injections as Diagnostic or Therapeutic Tool in Thoracic Outlet Syndrome.

BACKGROUND: The optimal diagnostic and treatment algorithm for patients with suspected thoracic outlet syndrome (TOS) remains challenging. Botulinum toxin (BTX) muscle injections have been suggested to shrink muscles in the thoracic outlet reducing neurovascular compression. This systematic review evaluates the diagnostic and therapeutic value of BTX injections in TOS. METHODS: A systematic review of studies reporting BTX as a diagnostic or therapeutic tool in TOS (or pectoralis minor syndrome as TOS subtype) was conducted in PubMed, Embase, and CENTRAL databases on May 26, 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed. Primary end point was symptom reduction after primary procedure. Secondary end points were symptom reduction after repeated procedures, the degree of symptom reduction, complications, and duration of clinical effect. RESULTS: Eight studies (1 randomized controlled trial [RCT], 1 prospective cohort study, and 6 retrospective cohort studies) were included reporting 716 procedures in at least 497 patients (at minimum 350 primary and 25 repeated procedures, residual unclear) diagnosed with presumably only neurogenic TOS. Except for the RCT, the methodological quality was fair to poor. All studies were designed on an intention to treat basis, one also investigated BTX as a diagnostic tool to differentiate pectoralis minor syndrome from costoclavicular compression. Reduction of symptoms was reported in 46-63% of primary procedures; no significant difference was found in the RCT. The effect of repeated procedures could not be determined. Degree of symptom reduction was reported by up to 30-42% on the Short-form McGill Pain scale and up to 40 mm on a visual analog scale. Complication rates varied among studies, no major complications were reported. Symptom relief ranged from 1 to 6 months. CONCLUSIONS: Based on limited quality evidence, BTX may provide short-lasting symptom relief in some neurogenic TOS patients but remains overall undecided. The role of BTX for treatment of vascular TOS and as a diagnostic tool in TOS is currently unexploited.

Optimal Antiplatelet Therapy in Moderate to Severe Asymptomatic and Symptomatic Carotid Stenosis: A Comprehensive Review of the Literature.

OBJECTIVES: Carotid stenosis patients are at risk of vascular events despite antiplatelet therapy. Data on prescribed antiplatelet regimens have not been comprehensively collated from trials to guide optimal therapy in this population. METHODS: This review was conducted in line with the current Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Medline, Ovid, Embase, Web of Science, and Google Scholar from 1988 to 2018 were searched using the search terms "carotid stenosis", "asymptomatic", "symptomatic", "antiplatelet", and "anti-platelet" to identify randomised trials in patients with asymptomatic or symptomatic extracranial moderate-severe carotid stenosis on any form of antiplatelet therapy in which vascular events and pre specified composite outcome events were reported. RESULTS: Twenty-five studies were judged eligible for inclusion. Data from one randomised controlled trial showed no significant difference in benefit with aspirin versus placebo in asymptomatic carotid stenosis, but it is still reasonable to recommend aspirin (81-325 mg daily) for prevention of vascular events in these patients. Low to medium dose aspirin (81-325 mg daily) is superior to higher doses (>650 mg daily) at preventing recurrent vascular events in patients undergoing endarterectomy. Data from endovascular treatment (EVT) trials support peri-procedural treatment of asymptomatic and symptomatic patients with 81-325 mg of aspirin daily. The use of peri-procedural aspirin-clopidogrel in patients undergoing EVT is based on one pilot trial, but appears safe. Short-term aspirin-dipyridamole or aspirin-clopidogrel treatments are equally effective at reducing micro-embolic signals on transcranial Doppler ultrasound in patients with ≥50% symptomatic carotid stenosis. There is insufficient evidence to recommend routine aspirin-clopidogrel combination therapy to reduce the risk of recurrent clinical ischaemic events in patients with symptomatic moderate-severe carotid stenosis. CONCLUSIONS: This comprehensive review outlines an evidence based approach to antiplatelet therapy in carotid stenosis patients. Future trials should randomise such patients to receive different antiplatelet regimens to assess their efficacy and safety and to optimise peri-procedural and long-term preventive treatment in this patient cohort.

Editor's Choice - Cerebral Hyperperfusion Syndrome After Carotid Artery Stenting: A Systematic Review and Meta-analysis.

INTRODUCTION: Cerebral hyperperfusion syndrome (CHS) is a preventable cause of stroke after carotid endarterectomy (CEA). There are currently no pooled data available on the incidence of CHS after carotid artery stenting (CAS). The aim of this review was to assess the relevance of CHS in the procedural stroke rate following CAS. METHOD: A systematic search on incidence rates of CHS after CAS was conducted in the MEDLINE, EMBASE, and Cochrane databases in November 2017. A meta-regression analysis was performed on CHS to explain heterogeneity and determine the impact of potential risk factors on observed CHS. The methodological quality of the included studies was assessed using the Cowley criteria. RESULTS: The pooled CHS risk across 33 studies concerning 8731 CAS patients was 4.6% (3.1-6.8%). Stroke occurred in 47% of CHS patients, of which 54% were fatal or disabling. Average time from procedure to symptoms was 12 h (IQR 8-36 h). Impaired cerebrovascular reserve (CVR) was associated with a higher risk of CHS after CAS (RR 5.18; 95% CI 1.0-26.8; p = .049). Symptomatic status was associated with a lower risk of CHS (RR 0.20; 95% CI 0.07-0.59; p = .001). CONCLUSION: CHS is a serious and frequent complication in patients undergoing carotid angioplasty with stenting, and is most likely to occur in the very early post-procedural period. Future studies are encouraged to investigate the effect of intensive haemodynamic monitoring, including blood pressure control and assessment of cerebral blood flow, on the incidence of stroke caused by CHS after CAS.

Management of atherosclerotic extracranial carotid artery stenosis.

Atherosclerosis leading to stenosis of the internal carotid artery is the underlying cause of 8-15% of ischaemic strokes (symptomatic carotid stenosis). 1-2% of the adult population have asymptomatic carotid stenosis. Clinical trials in patients with symptomatic carotid stenosis showed a higher procedural risk of non-disabling stroke with stenting versus endarterectomy, but a higher risk of myocardial infarction, cranial nerve palsy, and access site haematoma with endarterectomy. Apart from procedural complications, both treatments are equally effective in preventing stroke and recurrent severe carotid stenosis in the medium-to-long term. Endarterectomy has a modest effect in preventing stroke among patients with asymptomatic carotid stenosis, whereas the role of stenting remains to be established. With advances in medical therapy against atherosclerosis, benefit from invasive therapy has become uncertain. Risk modelling, with the inclusion of brain and carotid plaque imaging, will become increasingly important in selecting patients for interventions.