Prehospital transdermal glyceryl trinitrate in patients with ultra-acute presumed stroke (RIGHT-2): an ambulance-based, randomised, sham-controlled, blinded, phase 3 trial

Remote Ischemic Conditioning After Stroke Trial 2: A Phase IIb Randomized Controlled Trial in Hyperacute Stroke

Background Repeated episodes of limb ischemia and reperfusion (remote ischemic conditioning [RIC]) may protect the brain from ischemic reperfusion injury. Methods and Results We performed a phase IIb blinded dose-escalation sham-controlled trial in patients with hyperacute stroke, randomized 1:1 to receive RIC (four 5-minute cycles) or sham to the nonparetic upper limb, in 3 blocks of increasing dose, starting within 6 hours of ictus. The primary outcome was trial feasibility (recruitment, attrition). Secondary outcomes included adherence, tolerability, safety (serious adverse events), plasma biomarkers at days 1 and 4 (S100-ß protein, matrix metalloproteinase-9, and neuron-specific enolase), and functional outcome. Sixty participants were recruited from 2 centers (3 per month) with no loss to follow-up: time to randomization 4 hours 5 minutes (SD 72 minutes), age 72 years (12), men 60%, blood pressure 154/80 mm Hg (25/12), National Institutes of Health Stroke Scale 8.4 (6.9), and 55% thrombolyzed. RIC was well tolerated with adherence not differing between RIC and sham, falling in both groups on day 3 (P=0.001, repeated measures ANOVA) because of discharge or transfer. S100ß increased in the sham group (mean rise 111 pg/mL [302], P=0.041, repeated measures ANCOVA) but not the RIC group. There were no differences in matrix metalloproteinase-9, neuron-specific enolase, number with serious adverse events (RIC 10 versus sham 10, P=0.81), deaths (2 versus 4, P=0.36), or modified Rankin Scale score (2 [interquartile range 1-4], 2 [interquartile range, 1-3]; P=0.85). Conclusions RIC in hyperacute stroke is feasible when given twice daily for 2 days and appears safe in a small population with hyperacute stroke. A larger phase III trial is warranted. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT02779712.

Optimising ambulance service contribution to clinical trials: a phenomenological exploration using focus groups

Introduction:

Out-of-hospital cardiac arrest trials can prove challenging and there is a need to share learning from those that have recruited successfully. We have just completed three years of recruitment to PARAMEDIC2, a placebo-controlled trial of adrenaline in out-of-hospital cardiac arrest. This study was designed to describe the experience of operational ambulance staff involved in recruiting patients into PARAMEDIC2.

Methods:

Four focus groups involving trial paramedics and supporting members of the emergency care team were conducted across different geographical regions of a single UK ambulance service participating in the PARAMEDIC2 study. Data analysis was supported by NVivo 12 and themes were identified using a thematic analysis approach.

Results:

Forty-four participants contributed to the focus groups. Four overarching themes were identified: context for the research, ethical concerns, concerns at the patient’s side and ongoing trial support. Participants felt that research such as PARAMEDIC2 is important and necessary to drive medical progress. They valued the opportunity to be part of a large project. Due to the deferred consent model employed, public awareness of the trial was felt to be important. Most expressed equipoise regarding adrenaline, but some felt concerned about enrolling younger patients and there was discussion around what constitutes a successful outcome. Struggles with ethical concerns were overcome through training and one-to-one discussion with research paramedics. Participants valued feedback on their performance of trial tasks, but also wanted feedback on their resuscitation skills. Cardiac arrest places a high cognitive demand on paramedics; simplicity and reinforcement of trial processes were key to facilitating recruitment. Caring for relatives was a high priority for paramedics and some felt conflicted about not discussing the trial with them.

Conclusions:

This study has provided insights into paramedic experience of a large-scale pre-hospital trial. Investment in time and resource to provide face-to-face training and personalised feedback to paramedics can foster engagement and optimise performance.

A multicentre, randomised, sham-controlled trial on REmote iSchemic conditioning In patients with acute STroke (RESIST) - Rationale and study design

Rationale

Remote ischaemic conditioning, applied in the prehospital setting and continued in-hospital, may improve functional outcome in patients with acute ischaemic stroke and intracerebral haemorrhage.

Aims

To evaluate whether combined remote ischaemic per- and postconditioning can improve long-term functional outcome in acute ischaemic stroke and intracerebral haemorrhage patients.

Methods and design

Danish multicentre, prospective, randomised, patient-assessor blinded, sham-controlled study. Adult patients with a putative stroke identified prehospital with symptom duration <4 h, who are independent in daily activities will be randomised 1:1 to remote ischaemic conditioning or Sham-remote ischaemic conditioning. The treatment protocol will be five cycles, each consisting of 5 min with a blood pressure cuff inflation and 5 min with a deflated cuff placed on the upper extremity. The cuff pressure for remote ischaemic conditioning will be 200 mmHg-285 mmHg according to the individual systolic blood pressure and 20 mmHg sham-remote ischaemic conditioning during inflation. The study is approved as an acute study and consent is waived in the acute phase.Sample size estimation: For a 7% increased odds for a beneficial shift on the modified Rankin Scale at a significance level of 5% and power of 90%, 1000 patients with a target diagnosis of acute ischaemic stroke and intracerebral haemorrhage and a total of 1500 patients with a prehospital presumed stroke will be included.Study outcomes: The primary outcome will be the modified Rankin Scale score measured at three-month follow-up (analysed using ordinal logistic regression). ClinicalTrials.gov Identifier: NCT03481777.

Management of blood pressure in stroke

Objective

In this review and opinion piece, we discuss recent United States (US)-based guidance statements on the management of BP in stroke according to stroke type and stage of stroke.

Methods

We reviewed the most recent guidance statements on BP control from United States (US)-based organizations such as the American Heart Association/American Stroke Association (AHA/ASA) and American College of Cardiology (ACC), and articles available to the authors in their personal files.

Results

The key BP target before starting alteplase (t-PA) is < 185/110 mm Hg, and the maintenance BP after tPA administration is < 180/105 mm Hg. For IPH patients with systolic BP between 150 and 220 mm Hg and no contraindication to acute BP reduction therapy, acute lowering to 140 mm Hg systolic BP is safe. For persons with small vessel or lacunar cerebral ischemia, a reasonable BP lowering target is < 130 mm Hg systolic. For primary stroke prevention, the target BP for those with hypertension is < 140/90 mm Hg and self-measured BP is recommended to assist in BP control. Recent study and guidance suggest a BP target of <130/80 mm Hg for both primary and recurrent stroke prevention. BP control is reasonable for the prevention of cognitive decline or dementia.

Conclusions

BP targets for the proper management of stroke vary by chronological stage of stroke and by stroke subtype. Furthermore, consideration should be given to control of BP variability, especially in the acute phases of stroke, as it may play a role in conferring longer term outcomes.

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Stroke is an important cause of morbidity and mortality worldwide, and is well suited for prevention and acute treatment with proper BP management.

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BP targets in acute ischemic stroke vary whether intravenous alteplase is administered or an endovascular intervention is implemented or not.

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In acute intraparenchymal hemorrhage of the brain (IPH), it is reasonable to lower BP to a systolic level of 140–150 or up to 160 mm Hg.

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For both first and recurrent stroke prevention it is reasonable to aim for a BP target of <130/80 mm Hg based on the recent data.

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The revised BP target has been lowered to <130/80 mm Hg for prevention of major cardiovascular outcomes including stroke.

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Intensive BP control potentially preserves cognition, brain health, and brain structural integrity.

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Blood pressure variability is a new target for study in the acute treatment and prevention of stroke.

Ischaemic stroke

Stroke is the second highest cause of death globally and a leading cause of disability, with an increasing incidence in developing countries. Ischaemic stroke caused by arterial occlusion is responsible for the majority of strokes. Management focuses on rapid reperfusion with intravenous thrombolysis and endovascular thrombectomy, which both reduce disability but are time-critical. Accordingly, improving the system of care to reduce treatment delays is key to maximizing the benefits of reperfusion therapies. Intravenous thrombolysis reduces disability when administered within 4.5 h of the onset of stroke. Thrombolysis also benefits selected patients with evidence from perfusion imaging of salvageable brain tissue for up to 9 h and in patients who awake with stroke symptoms. Endovascular thrombectomy reduces disability in a broad group of patients with large vessel occlusion when performed within 6 h of stroke onset and in patients selected by perfusion imaging up to 24 h following stroke onset. Secondary prevention of ischaemic stroke shares many common elements with cardiovascular risk management in other fields, including blood pressure control, cholesterol management and antithrombotic medications. Other preventative interventions are tailored to the mechanism of stroke, such as anticoagulation for atrial fibrillation and carotid endarterectomy for severe symptomatic carotid artery stenosis.

Abnormal cardiovascular response to nitroglycerin in migraine

Introduction

Migraine and vasovagal syncope are comorbid conditions that may share part of their pathophysiology through autonomic control of the systemic circulation. Nitroglycerin can trigger both syncope and migraine attacks, suggesting enhanced systemic sensitivity in migraine. We aimed to determine the cardiovascular responses to nitroglycerin in migraine.

Methods

In 16 women with migraine without aura and 10 age- and gender-matched controls without headache, intravenous nitroglycerin (0.5 µg·kg⁻¹·min⁻¹) was administered. Finger photoplethysmography continuously assessed cardiovascular parameters (mean arterial pressure, heart rate, cardiac output, stroke volume and total peripheral resistance) before, during and after nitroglycerin infusion.

Results

Nitroglycerin provoked a migraine-like attack in 13/16 (81.2%) migraineurs but not in controls (p = .0001). No syncope was provoked. Migraineurs who later developed a migraine-like attack showed different responses in all parameters vs. controls (all p < .001): The decreases in cardiac output and stroke volume were more rapid and longer lasting, heart rate increased, mean arterial pressure and total peripheral resistance were higher and decreased steeply after an initial increase.

Discussion

Migraineurs who developed a migraine-like attack in response to nitroglycerin showed stronger systemic cardiovascular responses compared to non-headache controls. The stronger systemic cardiovascular responses in migraine suggest increased systemic sensitivity to vasodilators, possibly due to insufficient autonomic compensatory mechanisms.

Prehospital Transdermal Glyceryl Trinitrate for Ultra-Acute Intracerebral Hemorrhage: Data From the RIGHT-2 Trial

Supplemental Digital Content is available in the text.

Pilot trials suggest that glyceryl trinitrate (GTN; nitroglycerin) may improve outcome when administered early after stroke onset.

[Intracerebral hemorrhage: hot topics]

Significant advances in the acute treatment of patients with intracerebral hemorrhage (ICH) have been achieved in recent years. While many randomized trials have provided neutral results, important findings have been generated for the design of follow-up studies. Furthermore, a number of observational studies have been published, which in turn provide the basis for further methodologically stronger investigations. The focus is on avoidance of early bleeding progression, which can be influenced by blood pressure management and hemostasis. Furthermore, ICH surgery may experience a renaissance through minimally invasive techniques. In addition, perihemorrhagic edema and its pharmacological modulation are becoming increasingly more important. Optimal treatment of ventricular involvement is continuing to develop dynamically. Finally, long-term antithrombotic treatment has been intensely studied in observational analyses and is currently being investigated in randomized trials. This article addresses these most relevant topics in acute and long-term treatment of ICH patients and provides an overview of current debates in these areas of treatment.

Multicentre Randomised trial of Acute Stroke treatment in the Ambulance with a nitroglycerin Patch (MR ASAP): study protocol for a randomised controlled trial

BACKGROUND

Some studies have suggested that transdermal administration of glyceryl trinitrate (GTN; nitroglycerin) in the first few hours after symptom onset increases the chance of a favourable outcome after ischaemic stroke or intracerebral haemorrhage, possibly through an increase in intracranial collateral blood flow and a reduction in blood pressure. The Multicentre Randomised trial of Acute Stroke treatment in the Ambulance with a nitroglycerin Patch (MR ASAP) aims to assess the effect of transdermal GTN, started within 3 h after stroke onset in the prehospital setting, on functional outcome at 90 days in patients with acute ischaemic stroke or intracerebral haemorrhage.

METHODS

MR ASAP is a phase III, multicentre, randomised, open-label clinical trial with a blinded outcome assessment. A total of 1400 adult patients with suspected stroke and a systolic blood pressure ≥ 140 mmHg will be randomised to transdermal GTN (5 mg/day), administered as a transdermal patch by paramedics in the prehospital setting within 3 h of stroke onset and continued for 24 h or to standard care. The primary outcome is the score on the modified Rankin Scale (mRS) at 90 days, analysed with ordinal logistic regression. Secondary outcomes include blood pressure and collateral circulation at hospital admission, neurological deficit measured with the National Institutes of Health Stroke Scale at 24 h, and mortality and poor outcome (mRS score 3 to 6) at 90 days. This trial will be conducted in the Netherlands and will use a deferred consent procedure. The trial is part of the Collaboration for New Treatments of Acute Stroke (CONTRAST) programme.

DISCUSSION

MR ASAP will assess whether very early administration of GTN improves outcome after stroke in a setting where rates of intravenous thrombolysis and endovascular treatment for acute ischaemic stroke are high. The deferred consent procedure facilitates prompt GTN treatment and will prevent delay to revascularisation therapies. If early transdermal GTN treatment proves to be effective, this low-cost treatment can be readily implemented into daily clinical practice.

TRIAL REGISTRATION

ISRCTN Registry, ISRCTN99503308 . Registered on 2 January 2018.

Management of Blood Pressure After Acute Ischemic Stroke

PURPOSE OF REVIEW

The present manuscript examines the significance of blood pressure elevation in patients with acute ischemic stroke, the physiologic principles worthy of consideration during its treatment, and the recent empirical evidence that should guide management protocols. It also provides a sound and practical approach to treatment along the time continuum, with particular relevance to reperfusion strategies.

RECENT FINDINGS

The existing evidence shows that both insufficient and excessive blood pressures are detrimental to the outcome of patients with acute ischemic stroke. This "U-shaped" relation, however, relates to measurements at the time of presentation, and clinical studies lack detail and specificity relative to differential measurements along the time continuum, particularly prior to and following reperfusion. Extrapolating from recent series, it is possible to construct treatment protocols balanced for effectiveness and safety. The management of blood pressure after acute ischemic stroke is an important, complex, and challenging aspect of care, requiring a thorough understanding of cerebrovascular physiology. Along the time continuum, the therapeutic priorities start with the preservation of penumbral tissue prior to reperfusion and then follow with the limitation of the damaging effects of excessive blood pressure readings after reperfusion, optimizing the chances of improved outcomes.

It is safe to use transdermal glyceryl trinitrate to lower blood pressure in patients with acute ischaemic stroke with carotid stenosis

Background

There is concern that blood pressure (BP) lowering in acute stroke may compromise cerebral perfusion and worsen outcome in the presence of carotid stenosis. We assessed the effect of glyceryl trinitrate (GTN) in patients with carotid stenosis using data from the Efficacy of Nitric Oxide in Stroke (ENOS) Trial.

Methods

ENOS randomised 4011 patients with acute stroke and raised systolic BP (140-220 mm Hg) to transdermal GTN or no GTN within 48 hours of onset. Those on prestroke antihypertensives were also randomised to stop or continue their medication for 7 days. The primary outcome was the modified Rankin Scale (mRS) at day 90. Ipsilateral carotid stenosis was split: <30%; 30-<50%; 50-<70%; ≥70%. Data are ORs with 95% CIs adjusted for baseline prognostic factors.

Results

2023 (60.5%) ischaemic stroke participants had carotid imaging. As compared with <30%, ≥70% ipsilateral stenosis was associated with an unfavourable shift in mRS (worse outcome) at 90 days (OR 1.88, 95% CI 1.44 to 2.44, p<0.001). Those with ≥70% stenosis who received GTN versus no GTN had a favourable shift in mRS (OR 0.56, 95% CI 0.34 to 0.93, p=0.024). In those with 50-<70% stenosis, continuing versus stopping prestroke antihypertensives was associated with worse disability, mood, quality of life and cognition at 90 days. Clinical outcomes did not differ across bilateral stenosis groups.

Conclusions

Following ischaemic stroke, severe ipsilateral carotid stenosis is associated with worse functional outcome at 90 days. GTN appears safe in ipsilateral or bilateral carotid stenosis, and might improve outcome in severe ipsilateral carotid stenosis.