Orolingual angioedema after alteplase therapy of acute ischaemic stroke: incidence and risk of prior angiotensin-converting enzyme inhibitor use

Angioedema After Use of Recombinant Tissue-Type Plasminogen Activators in Stroke

Angioedema without concomitant urticaria is a well-known complication of treatment with the recombinant tissue-type plasminogen activator (r-tPA) alteplase and its genetically modified variant tenecteplase. It is potentially lethal when causing airway obstruction and can require intubation. The latest guideline for the early management of patients with acute ischemic stroke from the American Heart Association/American Stroke Association advises to treat this complication initially by interfering with the histamine pathway. This article aims to clarify the pathophysiological mechanism of r-tPA-induced angioedema and provides several arguments that this condition is primarily bradykinin-mediated and hence should be treated initially by intervening with the bradykinin pathway. Second, other-less frequently reported-adverse symptoms after r-tPA therapy and their proposed pathophysiological mechanisms leading to specific treatment are described. This manuscript describes the need for an update of the section "3.5 IV alteplase" from the American Heart Association/American Stroke Association guideline to treat this r-tPA-induced angioedema adequately and prevent potentially fatal outcomes.

Substance Use Disorder as Risk Factor for Intubation in Angioedema: A Nationwide Cohort Study

OBJECTIVES

Individuals with angioedema (AE) are at high risk for airway compromise and often require endotracheal intubation. Patient factors predisposing one to airway compromise are not well described. The objective of this study is to examine whether substance use disorder (SUD) in patients with AE is associated with need for airway intervention.

METHODS

This population-based retrospective cohort study compared AE patients with SUD versus propensity-matched control groups. Outcomes were hospitalization, intubation, and tracheotomy. Using the TriNetX National Database, this study included 28,931 patients with SUD and 117,509 patients without SUD who presented with AE.

RESULTS

Among patients with AE, those with each subtype of SUD (alcohol, cannabis, cocaine, tobacco, and opioids) were found to have higher risk of severe AE compared to propensity-matched non-SUD cohorts. Rate of hospitalization after cohort matching ranged from 20.4% for tobacco use disorder to 30.4% for cocaine use disorder, all significantly higher than the 8.0% in a population without SUD. Each SUD subtype was associated with a higher rate of intubation compared with matched non-SUD groups, with cannabis use disorder having the highest relative risk (RR) of 3.67 (95% CI: 2.69-5.02). Tobacco (RR = 2.45, 95% CI: 1.79-3.34) and alcohol (RR = 2.82, 95% CI: 1.73-4.58) use disorders were both associated with significantly higher risk of tracheotomy.

CONCLUSION

These data suggest that patients with SUD, regardless of subtype, and after propensity matching for demographics and comorbidities are at higher risk for adverse outcomes when presenting with AE. This study highlights clinically relevant predictors of airway compromise.

LEVEL OF EVIDENCE

Level 3 Laryngoscope, 2024.

Tenecteplase-associated orolingual angioedema: A case report and literature review

PURPOSE

Orolingual angioedema (OA) secondary to administration of thrombolytic therapy is a rare, but serious, known adverse effect. Despite the lack of robust evidence for their use, C1 esterase inhibitors are recommended by guidelines for the treatment of refractory thrombolytic-associated OA. This report highlights the use of a C1 esterase inhibitor in a patient with tenecteplase-associated OA unresolved by antihistamine and corticosteroid therapy.

SUMMARY

A 67-year-old white male with a history of hypertension managed with lisinopril presented to the emergency department with acute onset of slurred speech and left-sided hemiparesis. Following workup, an outside hospital's neurology stroke team suspected an acute infarct and determined the patient to be a candidate for tenecteplase. Approximately 1 hour after tenecteplase administration, the patient began complaining of dyspnea and mild oral angioedema. Immediate interventions for OA management included intravenous therapy with dexamethasone 10 mg, diphenhydramine 25 mg, and famotidine 20 mg. After an additional 30 minutes, the patient's OA symptoms continued to progress and a C1 esterase inhibitor (Berinert) was administered. Shortly after administration of the C1 esterase inhibitor, the patient's symptoms continued to worsen, ultimately leading to endotracheal intubation. Following intubation, symptom improvement was noted, and the patient was safely extubated after 30 hours.

CONCLUSION

Although rare, OA is a potentially life-threatening complication of tenecteplase therapy and requires prompt pharmacological intervention to optimize patient outcomes. Currently, no single agent or treatment algorithm exists that has shown significant efficacy or safety in the setting of thrombolytic-associated OA. Until data are available for C1 esterase inhibitors in this application, these inhibitors should only be considered if there is continued symptom progression after intravenous administration of corticosteroids and antihistamines.

Neurologic and Psychiatric Manifestations of Bradykinin-Mediated Angioedema: Old and New Challenges

Neurologic manifestations have been occasionally described in patients with bradykinin-mediated angioedema. The existing literature is currently limited to case series and case reports mainly described in the hereditary forms (HAE) concerning central nervous system (CNS) involvement. On the contrary, very little is known about peripheral and autonomic nervous system manifestations. CNS involvement in HAE may present with symptoms including severe headaches, visual disturbance, seizures, and various focal and generalized deficits. In addition, a stroke-like clinical picture may present in HAE patients. In turn, some drugs used in patients with cardiovascular and neurologic disorders, such as recombinant tissue plasminogen activator (r-tPA) and angiotensin-converting enzyme inhibitors (ACEI), may produce medication-induced angioedema, resulting in a diagnostic challenge. Finally, most patients with HAE have higher levels of psychological distress, anxiety, and depression. With this review, we aimed to provide an organized and detailed analysis of the existing literature on neurologic and psychiatric manifestations of HAE to shed light on these potentially invalidating symptoms and lay the foundation for further personalized diagnostic pathways for patients affected by this protean disease.

Anaesthetic and peri-operative management for thrombectomy procedures in stroke patients

PURPOSE

To provide recommendations for the anaesthetic and peri-operative management for thrombectomy procedure in stroke patients DESIGN: A consensus committee of 15 experts issued from the French Society of Anaesthesia and Intensive Care Medicine (Société Française d'Anesthésie et Réanimation, SFAR), the Association of French-language Neuro-Anaesthetists (Association des Neuro-Anesthésistes Réanimateurs de Langue Francaise, ANARLF), the French Neuro-Vascular Society (Société Francaise de Neuro-Vasculaire, SFNV), the French Neuro-Radiology Society (Société Francaise de Neuro-Radiologie, SFNR) and the French Study Group on Haemostasis and Thrombosis (Groupe Français d'Études sur l'Hémostase et la Thrombose, GFHT) was convened, under the supervision of two expert coordinators from the SFAR and the ANARLF. A formal conflict-of-interest policy was developed at the outset of the process and enforced throughout. The entire guideline elaboration process was conducted independently of any industry funding. The authors were required to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide their assessment of quality of evidence.

METHODS

Four fields were defined prior to the literature search: (1) Peri-procedural management, (2) Prevention and management of secondary brain injuries, (3) Management of antiplatelet and anticoagulant treatments, (4) Post-procedural management and orientation of the patient. Questions were formulated using the PICO format (Population, Intervention, Comparison, and Outcomes) and updated as needed. Analysis of the literature was then conducted and the recommendations were formulated according to the GRADE methodology.

RESULTS

The SFAR/ANARLF/SFNV/SFNR/GFHT guideline panel drew up 18 recommendations regarding anaesthetic management of mechanical thrombectomy procedures. Due to a lack of data in the literature allowing to conclude with high certainty on relevant clinical outcomes, the experts decided to formulate these guidelines as "Professional Practice Recommendations" (PPR) rather than "Formalized Expert Recommendations". After two rounds of rating and several amendments, a strong agreement was reached on 100% of the recommendations. No recommendation could be formulated for two questions.

CONCLUSIONS

Strong agreement among experts was reached to provide a sizable number of recommendations aimed at optimising anaesthetic management for thrombectomy in patients suffering from stroke.

Tissue Plasminogen Activator-Induced Angioedema Involving a Posterior Cerebral Artery Infarct: A Case Presentation

BACKGROUND Angioedema is characterized by localized swelling of subcutaneous or submucosal tissue resulting from fluid extravasation due to the loss of vascular integrity. It most commonly occurs with exposure to allergens and certain medications, namely nonsteroidal anti-inflammatory agents and angiotensin-converting enzyme inhibitors. There have been few incidences of angioedema following the administration of tissue plasminogen activator. CASE REPORT We describe an 84-year-old woman with a history of hypertension managed with lisinopril who presented with an acute onset of right-sided hemiparesis, slurred speech, and right-sided hemianopsia. Urgent computed tomography of the head revealed subacute infarct of the left pons without hemorrhage. Intravenous alteplase was administered and within 30 min our patient developed severe orolingual edema requiring emergent intubation. Subsequent imaging revealed acute to subacute infarct of the left occipital lobe in the posterior cerebral artery region, consistent with her initial presenting symptoms. CONCLUSIONS Angioedema induced by tissue plasminogen activator occurs in approximately 1-5% of patients receiving thrombolysis for ischemic stroke and can be life-threatening. The risk is increased in patients taking angiotensin-converting enzyme inhibitors, in patients with ischemic strokes of the middle cerebral artery, and in the presence of C1 esterase inhibitor deficiency. This phenomenon is usually self-limited and treatment is supportive, although evidence supports the use of antihistamines, steroids, epinephrine, and complement inhibitors. Due to the severity of angioedema and the potential progression to airway compromise, it is crucial to closely monitor patients receiving tissue plasminogen activator.

Angioedemas associated with renin-angiotensin system blocking drugs: Comparative analysis of spontaneous adverse drug reaction reports

INTRODUCTION

Angioedema is a subcutaneous swelling typically affecting the face, larynx or pharynx. It is a known adverse drug reaction (ADR) of ACE inhibitors (ACEi), angiotensin-II-receptor blockers (ARBs) and aliskiren (renin inhibitor). Several studies have reported pathophysiological mechanisms and risk factors of ACEi-associated angioedemas, whereas little is known for ARBs and aliskiren. The aim of the study was to analyze comparatively ACEi versus ARBs and aliskiren angioedema reports contained in the European ADR database EudraVigilance with regard to reported risk factors and clinical phenotypes.

METHODS

All spontaneous angioedema reports received between 01/2010-06/2017 reporting either an ACEi, ARB, or aliskiren as "suspected/interacting" drug were identified using the Standardized MedDRA Query "angioedema (narrow)". In order to perform a comparative analysis, odds ratios (ORs) were calculated for angioedema reports of ACEi (n = 3.194) versus ARBs (n = 687) and aliskiren (n = 162).

RESULTS

More patients with a history of allergy were included in angioedema reports of ARBs (6.8%) and aliskiren (13.6%) versus ACEi (4.3%). "Urticaria" as an ADR was reported more frequently in angioedema reports of ARBs (18.5%) and aliskiren (9.0%) versus ACEi (5.0%). ACEi-associated angioedemas were more often designated as "life-threatening" compared to ARBs (OR 2.2 [1.6-2.9]) and aliskiren-associated angioedemas (OR 14.2 (3.5-57.4). Concomitant therapy with mTOR inhibitors (OR 4.3 [1.0-17.9]) and fibrinolytics (OR 7.8 [1.1-57.2]) was reported more often in ACEi versus ARBs angioedema reports.

CONCLUSION

The reported clinical phenotypes differed between ACEi versus ARBs and aliskiren angioedema reports. Differences between the patient populations as observed in our study or differences with regard to underlying pathomechanisms could account for this finding. Due to the methodological limitations of spontaneous reporting systems, we cannot draw a firm conclusion in this regard. Hence, further research is necessary to confirm our observation and elucidate the underyling causes.

Angioedema associated with thrombolysis for ischemic stroke: analysis of a case-control study

BACKGROUND

Bradykinin-mediated angioedema (AE) is a complication associated with thrombolysis for acute ischemic stroke. Risk factors are unknown and management is discussed.

OBJECTIVES

To clarify risk factors associated with bradykinin-mediated AE after thrombolysis for acute ischemic stroke.

METHODS

In a case-control study conducted at a French reference centre for bradykinin angiœdema, patients with thrombolysis for acute ischemic stroke and a diagnosis of bradykinin-mediated angiœdema, were compared to controls treated with thrombolysis treatment without angiœdema.

RESULTS

Fifty-three thrombolysis-related AE were matched to 106 control subjects. The sites of attacks following thrombolysis for ischemic stroke mainly included tongue (34/53, 64%) and lips (26/53, 49%). The upper airways were involved in 37 (70%) cases. Three patients required mechanical ventilation. Patients with bradykinin-mediated angiœdema were more frequently women [33 (62%) vs. 44 (42%); P = 0.01], had higher frequency of prior ischemic stroke [12 (23%) vs. 9 (8%); P = 0.01], hypertension [46 (87%) vs. 70 (66%); P = 0.005], were more frequently treated with angiotensin-converting enzyme inhibitor [37 (70%) vs. 28 (26%); P < 0.001] and were more frequently hospitalized in intensive care medicine [ICU; 11 (21%) vs. 5 (5%); P = 0.004]. In multivariate analysis, factors associated with thrombolysis-related AE were female sex [odds ratio (OR), 3.04; 95% confident interval (CI), 1.32-7.01; P = 0.009] and treatment with angiotensin-converting enzyme inhibitors [(OR), 6.08; 95% (CI), 2.17-17.07; P < 0.001].

CONCLUSIONS

This case-control study points out angiotensin-converting enzyme inhibitors and female sex as risk factors of bradykinin AE associated with thrombolysis for ischemic stroke.

Guidelines for the Early Management of Patients With Acute Ischemic Stroke: 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Background and Purpose- The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations in a single document for clinicians caring for adult patients with acute arterial ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 Acute Ischemic Stroke (AIS) Guidelines and are an update of the 2018 AIS Guidelines. Methods- Members of the writing group were appointed by the American Heart Association (AHA) Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. An update of the 2013 AIS Guidelines was originally published in January 2018. This guideline was approved by the AHA Science Advisory and Coordinating Committee and the AHA Executive Committee. In April 2018, a revision to these guidelines, deleting some recommendations, was published online by the AHA. The writing group was asked review the original document and revise if appropriate. In June 2018, the writing group submitted a document with minor changes and with inclusion of important newly published randomized controlled trials with >100 participants and clinical outcomes at least 90 days after AIS. The document was sent to 14 peer reviewers. The writing group evaluated the peer reviewers' comments and revised when appropriate. The current final document was approved by all members of the writing group except when relationships with industry precluded members from voting and by the governing bodies of the AHA. These guidelines use the American College of Cardiology/AHA 2015 Class of Recommendations and Level of Evidence and the new AHA guidelines format. Results- These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings. Conclusions- These guidelines provide general recommendations based on the currently available evidence to guide clinicians caring for adult patients with acute arterial ischemic stroke. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

A Case of Oropharyngeal Angioedema Following Intravenous Recombinant Tissue Plasminogen Activator (rt-PA) and Mechanical Thrombectomy

A 72-year-old housewife presented with ischemic cerebrovascular stroke. Intravenous thrombolysis using recombinant tissue plasminogen activator (rt-PA) followed by mechanical thrombectomy under general anesthesia were attempted. The patient developed stridor and tongue swelling, in addition to hypotension and bradycardia, 60 min after completion of the rt-PA infusion. The airway was intubated, and intramuscular adrenaline, together with intravenous hydrocortisone and diphenhydramine, were administered. On the second day, the tongue edema subsided, and the cuff leak test was negative. However, extubation was not attempted due to the development of brain edema. A tracheostomy was later performed, and the patient was weaned off mechanical ventilation.

Orolingual Angioedema After Tissue Plasminogen Activator Administration in Patients Taking Angiotensin-Converting Enzyme Inhibitors

Orolingual angioedema is a rare adverse effect (1%-5%) of tissue plasminogen activator (tPA) that can lead to significant morbidity in patients with acute ischemic stroke. It is thought that increased levels of bradykinin and histamine resulting from tPA administration can result in angioedema. Angiotensin-converting enzyme (ACE) inhibitors can also lead to increased levels of bradykinin and appear to be a risk factor for tPA-associated angioedema. A literature review was conducted to examine previous cases of orolingual angioedema associated with tPA administration in patients also taking ACE inhibitors to better understand the relationship between ACE inhibitors and tPA-induced angioedema. Over a 20-year period, 27 patients who experienced angioedema with tPA while on ACE inhibitor therapy were identified. In this patient population, the onset of angioedema symptoms appeared as soon as 15 min after the tPA bolus and as late as 2 hr after the tPA infusion. Most patients required a combination of supportive medications such as corticosteroids (81.5%), antihistamines (74%), and epinephrine (18.5%) for the management of angioedema. Severe presentations of orolingual angioedema resulted in intubation for airway protection (26%). Symptom resolution ranged from shortly after the administration of supportive medications to 72 hr after symptom onset. Orolingual angioedema after tPA administration has the potential to cause significant morbidity, indicating patients should be monitored closely for a few hours after administration for the development of airway compromise. ACE inhibitors should not be the preferred antihypertensive agents for patients who require blood pressure lowering prior to tPA administration.

Angioedema in Stroke Patients With Thrombolysis

Background and Purpose- Oral angioedema (OA) is a rare but life-threatening complication in patients with ischemic stroke receiving intravenous thrombolysis with r-tPA (recombinant tissue-type plasminogen activator). This study intended to determine associations between thrombolysis-related OA and ischemic stroke lesion sites using a voxel-wise lesion analysis. Methods- Prospective registry data were used to identify ischemic stroke patients with thrombolysis-related OA between 2002 and 2018. For the study registry, ethics approval was obtained by the Ethics Committee of the Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg (clinical registry registration: 377_17Bc). Ischemic stroke patients with thrombolysis treatment but without OA admitted in the years 2011 and 2012 comprised the control group. Ischemic lesions were manually outlined on magnetic resonance imaging (1.5T or 3T) or computed tomographic scans and transformed into stereotaxic space. We determined the lesion overlap and compared the absence or presence of OA voxel-wise between patients with and without lesions in a given voxel using the Liebermeister test. Stroke severity was rated using the National Institutes of Health Stroke Scale score, and blood pressure, heart rate, blood glucose levels, and body temperature were determined on admission. Results- Fifteen ischemic stroke patients with thrombolysis-related OA were identified. The voxel-wise analysis yielded associations between OA and ischemic lesions in the insulo-opercular region with a right hemispheric dominance. Mean blood pressure was significantly lower in patients with OA than in controls. Age, National Institutes of Health Stroke Scale scores, infarct volumes, heart rate, and blood glucose levels did not differ between patients with and without OA. Conclusions- The voxel-wise analysis linked thrombolysis-related OA to right insulo-opercular lesions. The lower blood pressure in patients with thrombolysis-related OA may reflect bradykinin effects causing vasodilatation and increasing vascular permeability.

Institutional Incidence of Severe tPA-Induced Angioedema in Ischemic Cerebral Vascular Accidents

Introduction

Tissue plasminogen activator (tPA) is commonly used in ischemic cerebral vascular accidents (CVAs). tPA is generally well tolerated; however, orolingual angioedema is a well-documented adverse effect. Angioedema is generally mild, transient, and unilateral but can manifest as severe, life-threatening upper airway obstruction requiring intubation. Reported incidence for all severities ranges from one to five percent, whereas reported incidence of severe cases ranges from 0.18 to 1 percent of patients receiving tPA for ischemic CVA. Angiotensin-converting enzyme (ACE) inhibitors and middle cerebral artery distribution have been associated with a higher risk of developing angioedema. The aim of this study is to evaluate the incidence of severe tPA-induced angioedema and its effects on length of stay (LOS) and death.

Methods

A retrospective chart review of patients receiving tPA for ischemic CVA from January 2014 through December 2016 was conducted at a large tertiary center with Comprehensive Stroke Center designation. Subjects were eighteen or older. Baseline demographics and clinical data were collected.

Results

147 patients were included with four developing severe angioedema due to tPA resulting in an incidence of 2.72%. All four were female. The median LOS was thirty days for patients with angioedema and twelve days for those without. The survival probability was higher in the angioedema group and mean time to death was twenty-two days in the angioedema group and twenty-one days in the nonangioedema group. Twenty-five patients died, one from the angioedema group. ACE inhibitor use was found to have an OR of 7.72.

Conclusion

This study found a higher incidence of severe angioedema than that reported. Development of severe angioedema increased length of stay but was not shown to worsen outcomes in regards to death. Consistent with previous studies, ACE inhibitor use was associated with a higher risk of developing angioedema.

Hereditary angioedema: the plasma contact system out of control

The plasma contact system contributes to thrombosis in experimental models. Even though our standard blood coagulation tests are prolonged when plasma lacks contact factors, this enzyme system appears to have a minor (if any) role in hemostasis. In this review, we explore the clinical phenotype of C1 esterase inhibitor (C1-INH) deficiency. C1-INH is the key plasma inhibitor of the contact system enzymes, and its deficiency causes hereditary angioedema (HAE). This inflammatory disorder is characterized by recurrent aggressive attacks of tissue swelling that occur at unpredictable locations throughout the body. Bradykinin, which is considered to be a byproduct of the plasma contact system during in vitro coagulation, is the main disease mediator in HAE. Surprisingly, there is little evidence for thrombotic events in HAE patients, suggesting mechanistic uncoupling from the intrinsic pathway of coagulation. In addition, it is questionable whether a surface is responsible for contact system activation in HAE. In this review, we discuss the clinical phenotype, disease modifiers and diagnostic challenges of HAE. We subsequently describe the underlying biochemical mechanisms and contributing disease mediators. Furthermore, we review three types of HAE that are not caused by C1-INH inhibitor deficiency. Finally, we propose a central enzymatic axis that we hypothesize to be responsible for bradykinin production in health and disease.

Angiotensin-converting Enzyme Inhibitor and Other Drug-associated Angioedema

Nonsteroidal antiinflammatory agents, β-lactam antibiotics, non-β lactam antibiotics, and angiotensin-converting enzyme inhibitors are the most common classes of drugs that cause angioedema. Drug-induced angioedema is known to occur via mechanisms mediated by histamine, bradykinin, or leukotriene, and an understanding of these mechanisms is crucial in guiding therapeutic decisions. Nonallergic angioedema occurs in patients with genetic variants that affect metabolism or synthesis of bradykinin, substance P, prostaglandins, or leukotrienes, or when patients are taking drugs that have synergistic mechanisms. The mainstay in treatment of nonallergic drug-induced angioedema is cessation of the offending agents.

2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations for clinicians caring for adult patients with acute arterial ischemic stroke in a single document. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 guidelines and subsequent updates.

METHODS

Members of the writing group were appointed by the American Heart Association Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. The members of the writing group unanimously approved all recommendations except when relations with industry precluded members voting. Prerelease review of the draft guideline was performed by 4 expert peer reviewers and by the members of the Stroke Council's Scientific Statements Oversight Committee and Stroke Council Leadership Committee. These guidelines use the American College of Cardiology/American Heart Association 2015 Class of Recommendations and Levels of Evidence and the new American Heart Association guidelines format.

RESULTS

These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings.

CONCLUSIONS

These guidelines are based on the best evidence currently available. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Bradykinin: Inflammatory Product of the Coagulation System

Episodic and recurrent local cutaneous or mucosal swelling are key features of angioedema. The vasoactive agents histamine and bradykinin are highly implicated as mediators of these swelling attacks. It is challenging to assess the contribution of bradykinin to the clinical expression of angioedema, as accurate biomarkers for the generation of this vasoactive peptide are still lacking. In this review, we will describe the mechanisms that are responsible for bradykinin production in hereditary angioedema (HAE) and the central role that the coagulation factor XII (FXII) plays in it. Evidently, several plasma parameters of coagulation change during attacks of HAE and may prove valuable biomarkers for disease activity. We propose that these changes are secondary to vascular leakage, rather than a direct consequence of FXII activation. Furthermore, biomarkers for fibrinolytic system activation (i.e. plasminogen activation) also change during attacks of HAE. These changes may reflect triggering of the bradykinin-forming mechanisms by plasmin. Finally, multiple lines of evidence suggest that neutrophil activation and mast-cell activation are functionally linked to bradykinin production. We put forward the paradigm that FXII functions as a ‘sensor molecule’ to detect conditions that require bradykinin release via crosstalk with cell-derived enzymes. Understanding the mechanisms that drive bradykinin generation may help to identify angioedema patients that have bradykinin-mediated disease and could benefit from a targeted treatment.

Factor XII: form determines function

Factor XII is a mysterious plasma protein without a clear physiologic function. It was identified as a clotting factor, but has no clear role in hemostasis. However, FXII also contributes to the production of bradykinin, a short-lived inflammatory peptide. A growing body of mechanistic research from animal models indicates that FXII contributes to thrombotic disease by triggering excessive coagulation. FXII is evolutionarily conserved, suggesting that this molecule does have a physiologic function. This leads to intriguing questions: What does FXII really do? Is it even a real clotting factor at all? Before the groundbreaking discovery of a role for FXII in thrombotic disease, many studies investigated the biochemical properties of FXII and its activators. In this review, we highlight several biochemical studies that reveal much about the natural behavior of FXII. On the basis of these findings, it is possible to draft a conceptual model to explain how FXII reacts to surface materials. We then discuss how this model applies to the activities of FXII in its natural environment. There are two tentative physiologic functions of FXII that can operate exclusively: (i) maintenance of thrombus stability; (ii) local regulation of vascular permeability. Either, or both, of these natural functions may explain the evolutionary development and maintenance of FXII.

Orolingual Angioedema During or After Thrombolysis for Cerebral Ischemia

Background and Purpose—

Orolingual angioedema (OLAE) is a life-threatening complication of intravenous thrombolysis. Our objective was to compare outcomes of patients with and without OLAE.

Methods—

We prospectively included consecutive patients who received intravenous thrombolysis for cerebral ischemia at Lille University Hospital. We examined tongue and lips every 15 minutes during thrombolysis and ≤30 minutes after. We evaluated the 3-month outcome with the modified Rankin scale (mRS) and compared outcomes of patients with and without OLAE.

Results—

Of 923 consecutive patients, 20 (2.2%) developed OLAE. None of them needed oro-tracheal intubation. They were more likely to be under angiotensin-converting enzyme inhibitors (adjusted odds ratio [adjOR], 3.9; 95% confidence interval [CI], 1.6–9.7; P =0.005) to have total insular infarcts (OR, 5.0; 95% CI, 1.5–16.5; P =0.004) and tended to develop more symptomatic intracerebral hemorrhages. Results concerning angiotensin-converting enzyme inhibitors were not modified after adjustment for propensity scores (OR, 4.4; 95% CI, 1.6–11.9; P =0.004) or matched analysis based on propensity scores (OR, 3.4; 95% CI, 1.3–8.1; P =0.010). Patients with OLAE did not significantly differ at 3 months for the proportion of patients with mRS score of 0 to 1 (adjOR, 0.9; 95% CI, 0.3–2.1), mRS score of 0 to 2 (adjOR, 0.8; 95% CI, 0.1–1.8), and death (adjOR, 1.1; 95% CI, 0.3–3.8).

Conclusions—

OLAE occurs in 1 of 50 patients who receive intravenous thrombolysis, 1 of 10 in case of total insular infarct, and 1 of 6 if they are under angiotensin-converting enzyme inhibitors. Their long-term outcome does not differ from that of other patients.

Cardiovascular Instability Preceded by Orolingual Angioedema after Alteplase Treatment

An 87-year-old man taking antihypertensive medications, including 10 mg enalapril, daily visited our hospital complaining of motor aphasia, dysarthria, and right hemiparesis. Magnetic resonance imaging revealed an ischemic lesion in the left frontal lobe including the insular cortex and severe stenosis of the left middle cerebral artery. After he received intravenous alteplase infusion, he developed orolingual angioedema followed by transient bradycardia with subsequent hypotension, resulting in the deterioration of his neurological signs and expansion of the ischemic lesion. Orolingual angioedema after intravenous alteplase infusion may follow cardiovascular instability and disease progression in stroke patients.

Management of Postthrombolysis Hemorrhagic and Orolingual Angioedema Complications

Intravenous recombinant tissue plasminogen activator was first approved for the treatment of acute ischemic stroke in the United States in 1996. Thrombolytic therapy has been proven to be effective in acute ischemic stroke treatment and shown to improve long-term functional outcomes. Its use is associated with an increased risk of symptomatic intracerebral hemorrhage as well as orolingual angioedema. Our goal is to outline the management strategies for these postthrombolysis complications.