Link To The Curbsiders’ Podcast And Show Notes “#385 TIA/Stroke for the Hospitalist featuring Dr. Karima Benameur” With Links To Two Additional Resources From Practical Neurology

In addition to today’s resource, please review

• Intracranial Atherosclerotic Disease, JANUARY 2019, from Practical Neurology
  • Introduction
    • “Intracranial atherosclerotic disease (ICAD) can affect cerebral arteries distal to the internal carotid arteries (ICAs) after they enter the petrosal bone (C2 segment) and the vertebral arteries after they enter the foramen magnum and pierce the dura mater (V4 segment).¹ As such, ICAD is not amenable to surgical revascularization, making it a very different and independently important disease entity from extracranial carotid disease. In autopsy studies, ICAD accounted for 10% of strokes,² and in a pooled analysis of 2,593 patients, it was at least somewhat present in 3.5% to 13% of the population, varying with age and ethnicity.³ For the practicing neurologist, diagnosing and treating ICAD can be challenging because it can masquerade as and be confused with other conditions and because ICAD is associated with high rates of recurrent stroke. Here, we briefly discuss the epidemiology and pathophysiology of ICAD and strategies for acute and long-term management.
  • Natural History
    • “The natural history of patients with ICAD comprises 3 predominant courses that may coexist: transient ischemic attack (TIA), recurrent ischemic stroke, and chronic hypoperfusion that can cause cumulative white matter damage and gradual cognitive worsening.7 Among TIA presentations, limb-shaking TIAs are peculiar transient symptoms frequently associated with high-grade stenosis, often in the ICA. They typically present as repetitive short duration paresis and “shaking,” sometimes triggered by exertion, caused by altered cerebrovascular hemodynamics.11 Recurrent ischemic stroke ipsilateral to a stenotic artery has been shown to range from 3.1% to 8.1% per year with annual mortality ranging from 7.8% to 17.2%.12 Generally, the highest risk of recurrent stroke is in the first 2 years, regardless of location of ICAD, and half of that risk is within the first month of the index stroke or TIA. There is less study of progressive cognitive consequences of ICAD. However, a prior study noted that 34% of subjects had dementia attributed primarily to ICAD.13”
  • Management
    • Acute Care
      • All patients with ischemic stroke presenting within the windows for thrombolysis or endovascular therapy should be evaluated and managed according to the current guideline, whether they are eventually found to have ICAD or not.
• Asymptomatic Carotid Artery Stenosis, JANUARY 2019, from Practical Neurology
  • Introduction
    • “Carotid artery stenosis accounts for 8% to 15% of acute stroke,1 the importance of which is magnified by the high rate of early recurrence after an initial event, up to 21% at 2 weeks and 32% at 12 weeks.2 Understanding and maximizing primary prevention strategies for asymptomatic carotid stenosis is therefore critical. Over the past decade, there has been a shift in thinking about management of patients with asymptomatic carotid artery disease, including reassessment of carotid endarterectomy (CEA) vs carotid artery stenting (CAS) vs medical management alone. Surgical trials in the 1990s demonstrated benefit in patients with more than 50% stenosis for patients with symptoms and more than 60% for patients who are asymptomatic; however, improving outcomes with statin use and more aggressive blood pressure control has since equalized the playing field and generated new questions about ideal treatment strategies.3,4 In addition, cognitive function has emerged as an important outcome in carotid artery disease.”
  • What Do We Tell Our Patients?
    • “Management of asymptomatic carotid stenosis has evolved over the past 10 years. The seminal surgical studies that suggested revascularization would reduce stroke rate more than modern medical management may no longer be true. Aggressive medical management that includes controlling blood pressure to a target of 130/80 mm Hg, treating atherosclerosis with high potency, high-dose statins, and managing lifestyle choices of diet and exercise has become standard of care. Many vascular neurologists are eschewing CEA and CAS for patients with asymptomatic carotid stenosis and focusing on medical management alone. For clinical decision making for who should be sent for revascularization, testing for plaque instability, microemboli, and hemodynamic status may help determine which asymptomatic patients are at highest risk for stroke. With the CREST-2 trial, we now have a chance to rigorously retest our assumptions about surgical and interventional revascularization. Finally, cognitive function has emerged as an important outcome consideration. If cognitive impairment exists among a subset of our patients with asymptomatic carotid stenosis, we may need to re-assign them to symptomatic status, and consider the possibility that the cognitive impairment may be reversible with revascularization.”

Today, I reviewed and link to The Curbsiders‘ #385 TIA/Stroke for the Hospitalist featuring Dr. Karima Benameur*.

*Benameur M, Amin M, Trubitt M, Coleman C. “#385 Inpatient Stroke Management”. The Curbsiders Internal Medicine Podcast. https://thecurbsiders.com/episode-list March 13, 2023

Note to myself: I only put in excerpts from the show notes in this post. I do this because it helps to fix the material in my memory (spaced repition). So when I’m reviewing this material, I need to review the orginal complete Curbsiders shownotes.

All that follows is from the outstanding show notes.

Download the Transcript

We’ve got the hard-hitting questions and must-know answers on all things TIA and stroke from neurology expert, Dr. Karima Benameur (Emory University). Topics: TIA and stroke supportive management, indicated workup, and anticoagulation and antiplatelet management pearls for the hospitalist.

TIA/Stroke for the Hospitalist Pearls

1. A non-contrast CT head should be obtained immediately for all patients with clinical suspicion of stroke, to both evaluate for stroke and assess appropriateness for potential interventions.
2. If patients present <24 hours of last seen normal, CT angiogram head and neck and CT perfusion should be obtained as well to assess for tPA or thrombectomy candidacy.  If >24 hours, either a CT OR MRI can be used to obtain vessel imaging.
3. Supportive inpatient management includes permissive hypertension for 24-48 hours, avoiding fevers.
4. All patients can be started on 81 mg, with no indications for a loading dose or a double dose if they had a stroke already while on aspirin 81 mg. All patients can be continued on antiplatelets (e.g. aspirin, clopidogrel) and anticoagulation only needs to be held for ischemic strokes if the infarct is large (>⅓ the MCA territory).
5. DAPT with aspirin and clopidogrel is indicated for high risk TIAs and mild-moderate strokes for 3 weeks, as well as all TIAs and non-disabling strokes for 3 months if the patient has severe ICAD.
6. Initial ischemic stroke and TIA workup for all patients includes brain imaging, vessel imaging, and a cardiac workup to assess for cardioembolic etiology.

TIA/Stroke for the Hospitalist Show Notes

 

Initial triage, imaging, and assessing for interventions

When any patient presents with positive BE FAST (Balance, Eyes, Face droop, Arm weakness, Speech  – Time to call 911, or stroke alert if inpatient) symptoms, they should receive a rapid evaluation with vital signs, blood sugar and exam before going straight to imaging with a non-contrast CT head. This is because you must rule out a hemorrhagic stroke before considering thrombolytics (Aroor 2017).

If a patient arrives within the window of potential intervention (<24 hours), patients will also receive emergent vessel imaging with CT angiogram head and neck to assess for large vessel occlusion (LVO), as well as a CT head perfusion to assess for any potentially salvageable tissue (i.e., the core infarct versus the penumbra). Patients must be within 4.5 hours of last seen normal (not the time when deficits were discovered) to be an IV tPA candidate and within 24 hours to be a thrombectomy candidate, however there are multiple other criteria that go into making those decisions as well, such as the amount of salvageable tissue (i.e., the core-penumbra mismatch) seen on CT perfusion (Powers 2019, Greenberg 2022). Contraindications to tPA include hemorrhagic stroke, being on anticoagulation (including DOAC in previous 24 hours or being on warfarin with INR >1.5), a 3-month history of stroke, head trauma, or surgery, or any current active bleed.

Vessel imaging modalities

If the patient arrives >24 hours from last seen normal, there is no need for emergent vessel imaging, but it will still be part of the inpatient workup(Powers 2019). When deciding between CT and MRI for vessel imaging, Dr. Benameur discusses that there are pros and cons to both modalities. CTA is a quicker exam, is more widely available, has a slightly superior sensitivity/specificity compared to MRA, and is the only modality that has been studied in large RCTs for LVOs. MRA has advantages though as you can obtain it without contrast (i.e., a time-of-flight MRA) which is helpful for CKD patients or patients with a contrast allergy. It also has an advantage in that you can obtain MRA vessel wall imaging if you’re evaluating for vasculitis as a potential etiology of the stroke.

When to get a MRI brain

Dr. Benameur thinks about the MRI brain in practical terms. If the patient’s symptoms match what is demonstrated on CT, a MRI will likely not further change management and she does not usually recommend it. However, if the CT does not fully explain the patient’s presentations, an MRI is very helpful, and its multiple phases provide clinicians with lots of information. For example, diffusion imaging is the most sensitive modality for acute ischemia and can detect an acute infarct not demonstrated on CT.

TIA

TIA was previously defined as transient symptoms lasting <24 hours. However, with the advent of MRI and diffusion imaging, more patients were found to be experiencing transient symptoms with a MRI demonstrating stroke. Subsequently, the definition has shifted from being time-based to tissue-based, and is defined as transient symptoms without infarct seen on MRI.

The workup for TIA is identical to stroke. Similarly to NIHSS for stroke, the ABCD2 score can be used to measure severity of TIA and to guide treatment. High risk TIAs (ABCD2 ≥ 4) warrant 3 weeks of DAPT per the POINT (Johnston 2018) and CHANCE (Wang 2013) trials, whereas low risk TIAs should receive aspirin monotherapy. All should have cardiovascular risk factor modification, including hypertension.