Aberrant ICA pearls

Krings T, Geibprasert S, Cruz JP, et al.  Neurovascular Anatomy in Interventional Neuroradiology: A Case based approach. New York, Thieme, 2015. pp. 13-16.

 

1.  In ICA agenesis, APhA reconstitutes in horizontal petrous segment to form "distal ICA" and tympanic artery entering skull through Jacobsen's canal. 

 

2. Symptoms may be absent, or include pulsatile tinnitus, conductive hearing loss,  or a pulsatile retrotympanic mass. 

 

3. It can mimic glomus tumor, otosclerosis or AVM.  A temporal bone CT can help differentiate as aberrant ICA can show absent vertical segment of carotid canal, and lateral swing called line of Lapowyker beyond vestibular line

 

4.  Persistent stapedial artery exists in 0.5 percent of population and can present as pulsatile mass in middle ear cavity with or without pulsatile tinnitus.  Its associated with absent foramen spinosum.  It appears as a vessel  from petrous ICA supplying the MMA.

 

Pearls about aberrant subclavian artery

Krings T, Geibprasert S, Cruz JP, et al.  Neurovascular Anatomy in Interventional Neuroradiology: A Case based approach. New York, Thieme, 2015. pp. 6-9

 

1.  Its usually a remnant of distal right dorsal aorta distal to left subclavian artery, crossing midline to irrigate right upper extremity

 

2.  Diverticulum of Komerell, an outpouching of right dorsal aorta, arises as it crosses the  esophagus that occasionally compresses the esophagus and causes dysphagia "dysphagia lusoria", nonspecific thoracic pain, compression of trachea with dyspnea, or arteriotracheal or arterioesophageal fistulas wityh hematemesis or hemoptysis (very rare).  Even rarer is subclavian steal of ARSA

 

3. It can be inferred from anterior displacement of esophagus in mediastinum

 

4.  May need to intervene through the left vertebral artery which can be difficult 

Pioglitzaone after ischemic stroke

Kernan WN, Viscoli CM, Furie KL et al.  Pioglitazone after ischemic stroke or transient ischemic attack. NEJM 2016; 374:1321-31  and editorial Semenkovich CF.  Insulin resistance and along, strange trip. NEJM; 2016: 374:14-15.

 

Study shows that the drug pioglitozone  for secondary prevention in stroke/TIA is effective.  N=3876 pts v. placebo,  patients with no history of diabetes but with insulin resistance, who were given drug had less diabetes develop, more weight gain, edema and fracture, and less MI/CVA at mean 4.8 years.  Effect magnitude was fairly small, with primary outcome in 9.0 percent (175 patients) in active drug group and 11.8 % (228 patients) in placebo group. Patients on pioglitazone were more likely than placebo patients to stop drug due to side effects.

 

This is also known as the IRIS trial (insulin resistance after stroke).   

 

Editorial speculates patient selection is important to avoid side effects and profiling should include PPAR-y genes.

sammpris study risk factors for stroke w pct

Waters MF et al.  Factors associated with recurrent ischemic stroke in the Medical Group of the SAMMPRIS trial  JAMA Neurology 73:3 2016 pp.308-315

Endpoint: stroke or death within 30 days, stroke in appropriate arterial territory after 30 days.

Overall, risk of a primary endpoint was half of what was expected based on WASID or other studies.The highest risk features are prior stroke in the territory of the stenotic artery, stroke as the qualifying event, and absent statin use at time of enrollment. TRENDS occurred based on risk of higher degree of stenosis and presence of diabetes mellitus.  In WASID, degree of stenosis stratified risk with more risk with higher degree of artery stenosis.   The risk in WASID of stroke was 18 % in 70-79 %, but 31 % in 80-89%.  The groups were not analyzed separately in WASID, above is post hoc.  In Sammpris, only patients 70-99 % were enrolled, and the risk was 19 % with greater than 80 % stenosis, and 12 % with 70-79 % stenosis.  

For diabetics in Sammpris, diabetics reached an endpoint at a rate of 18 % v. 10 % for nondiabetics.  

By artery, the intracranial carotid had a risk of an endpoint of 23 %.  The VA and BA wer 9.3 and (.5 % respectively.  By gender, risk for women was 20.1 per cent, 10.7 % for men.

The risk factors for periprocedural stroke had little overlap, the main ones being in that arm being older age, nonsmoking status, diabetes and BA stenosis.

Patients in medical group with TIA alone had LOW risk at one and two years of 5.6 and 7 % respectively.

Exercise during followup was the most important determinant of outcome in the medical arm.  

Overall the risk of the medical arm in SAMMPRIS was 15 percent at 32 months.

Screening for neuro "clearance" before CABG PEARLS

based on a lecture at ISC 2016 Los Angelos

by Michael Mullen  U Penn

1.  Patient risk factors for perioperative stroke:  (odds ratio):  prior stroke (3.55), PVD, DM AND HTN (EACH around 1.3),  female (1.6).  If divided into early and late stroke, risk factors (odds ratios) for early stroke are prior stroke (11.6), female (6.9), ascending aorta atherosclerosis (2.0), time on bypass (1.1).  Delayed stroke : history of stroke (27.6), diabetes (2.8), female (2.4), low CO and AF (1.7_)  ascending aorta atherosclerosis (1.4)

2. Timing of surgery and risk of stroke after a prior stroke:  (odds ratio). No prior stroke (1.), any prior stroke, any mechanism (4.0);  < 3 monthds prior (14); 3-6 mo prior (4.9); 6-12 mo prior , 3.0; > 12 months prior(2.5).  Sweet spot is 9 months

3.  Carotid screening:  1. not recommended for noncasrdiac surgery   2.  For cardiac surgery scren high risk patients:  >65, left main disease, peripheral vascular disease, history of prior stroke or TIA, carotid bruit based on guidelines ACCF/AHA for CABG (2011) by Hillis et al,  and by Brott et al, on Extracranial caroitd disease.  Published in Circulation.

4.  Risk of stroke with carotid disease: metanalysis(2011) Li et al, JAMA Neurology, 2009.  Low stroke risk in unilateral, asymptomatic carotid stenosis suggests revascularization is not necessary.  Odds ratio for stroke in such patients is (2.0).  However, suggest maintaining arterial perfusion pressure in such patients.

5. In patients with bilateral 50-99 % stenosis, unilateral 50-99 + contralateral occlusion, asymptomatic, odds ratio is (6.5).   Among these patients its reasonable to consider revascularizing one side.

6.  How to sequence procedures: Staged CEA-CABG, combined CEA-CABG

or staged CAS- CABG.  Main risk of staged CEA-CABG is MI, of combined CEA-CABG is stroke.  If CABG is urgent, do a combined CEA-CABG.  If not urgent do staghed CAS-CABG.

White matter hyperintensity patterns

in cerebral amyloid angiopathy and hypertensive arteriopathy.  Neurology; 2016; 86: 505-511.  Authors Charidmou A, Boulouis G, Haley K, et al.

 

Authors studied 319 patients with cerebral amyloid angioapthy and 137 with hypertensive arteriopathy for different patterns of white matter hyperintensity in the two diseases. 

 

Results showed that the presence of multiple subcortical spots was higher in the CAA group, and the peribasal ganglia WMH pattern was more prevalent in the HA group.  Multiple spots was associated with presence of cortical cerebral microbleeds.

The risk of symptomatic carotid stenosis:the

future is not what it used to be.  Chaturvedi S, Rothwell PM.  Neurology 2016; 86-494-495 (editorial) and refers to

 

Johannson E, Cuadrado -Gida E, Hayden D., et al.  Recurrent stroke in symptomatic carotid stenosis awaiting revascularizatio: a pooled analysis. Neurology 2016; 86: 498-504  and to

 

Shahidi S. , Owen Falkenberg A, Hjerpsted U et al.  Urgent best medical therapy may obviate the need for urgent surgery in patients with symptomatic carotid stenosis.

 

Idea: Best medical therapy of today, "second generation medical therapy" including statins, dual antiplatelets, and optimal BP control was not used in NASCET trials in the 1990s.  Therefore, the studies are obsolete and need to be repeated.

 

The two studies mentioned above give opposite suggestions.  Johannson et al. studied patients from three European centers with 50-99% stenosis and recent stroke or tia, and found in 227 suitable patients, a pooled risk risk of ipsilateral stroke of 11.5 % at 14 days and 18.8 % at 90 days, with less risk as usual for retinal ischemia.  A single center in Denmark studied patients with severe carotid stenosis, symptomatic, awaiting CEA with 21st century modern best medical therapy  and found that the rate of events in patients fell from 29 to 2.5 % , with events being TIA's. 

 

They also suggest that the risk in patients with asympromatic stenosis has fallen with "optimal medical therapy" (see Marquardt L, Geraghty OC, Mehta Z et al.  Low risk of ipsilateral stroke in patients with asymptomatic carotid stenosis on best medical treatment: a prospective population based study. Stroke 2010; 41: e 11-e17  and Spence JD, Coates V, Li H et al.  Effects of intensive medical therapy on microemboli and cardiovascular risk in asymptomatic carotid stenosis.  ArchNeurol 2010; 67: 180-1`86.

AHA / ASA Scientific statement re exclusion/inclusion criteria for alteplase

 

Demaerschalk BM, Kleindorfer DO, Adeoye OM, et al.  AHA/ASA Scientific statement  for the inclusion and exclusion criteria for intravenous alteplase in acute ischemic stroke: a statement for healthcare professionals from the American Heart Association/ American Stroke Association.  Stroke 2016; 47:  1-61.

The above article was previously circulated .  It is not a practice parameter.   It functions as an FAQ / legal cover/ resource for many uncommon scenarios for stroke alerts.  It is not ORMC policy to abide by it.  However, it does summarize existing evidence well, and assigns a grade to the quality of the evidence (class/level of evidence) grades that have become popular. I am re-presenting it in tabular form so it is available during stroke alerts, if needed. 

Please circulate to any/all additional members of the team involved in stroke care that might wish to see it.  Thanks

Daniel Jacobs, MD, FAAN

Director , Orlando Health  Comprehensive Stroke Center

 

Zero to -3 hour window

Not an exclusion

1.  Age > 80

2.  severe stroke

3.  mild / rapidly improving but still disabling stroke

4.  coagulation studies not returned but no clinical suspicion of bleeding disorder 

warfarin use if INR is lower than OR EQUAL to 1.7

5. MI within three months if the MI was nSTEMI, or STEMI affecting the right or inferior myocardium

6.  GI/GU bleed more than 21 days ago

7.  History of cerebral microbleeds

8.  Unruptured cerebral aneurysm (unless a giant aneurysm)

9.  Intracranial extraaxial neoplasm

10. End stage renal disease with normal PTT

11.  Seizure at stroke onset  unless deficits are suspected to be due to postictal phenomenon

12.  Suspected extracranial cervical arterial dissection

13.  Lumbar puncture within 7 days

14. Post cerebral or cardiac catheterization related acute stroke

15.  Absent person to consent for an otherwise eligible patient

16.  Single or dual antiplatelet therapy

17.  Cocaine or other drug use as a possible cause of stroke

alteplase can be considered if benefits outweigh risks

1.  pregnancy esp moderate to severe deficit

2.  history of bleeding diathesis including renal or hepatic disease (consider on a case by case basis)

3.  use of NOAC's (novel anticoagulants) > 48 hours if renal dysfunction is present,may assess with lab (PT, PTT, platelet count, ecarin clotting time, thrombin time, or direct factor Xa activity) 

4.  Major surgery within 14 days- with careful selection and weighing the risk of hemorrhage at the site

5. Major trauma within 14 days on a case by case basis

6.  MI affecting the left anterior myocardium

7. Pericarditis with severe deficit after consulting a cardiologist

8. LV or LA thrombus with severe stroke likely to cause severe disability

9. History of recent stroke within three months

10.  Uncontrolled severe HTN > 185/110 unless it can be lowered safely in a stable fasion and monitored and kept low for 24 hours.

11. Dementia considering premorbid function, patient and family wishes and goals of therapy

12.  Current malignancy if no other contraindications and reasonable life expectancy (> 6 months)

13.  Preexisting major disability considering premorbid function, family wishes and goals of therapy

14.  Diabetic hemorrhagic retinopathy weighing and presenting risks of visual loss against stroke deficit

15.  Vaginal bleeding including menstruation that is monitored for 24 hour period; if anemia is present consider consulting GYN first

16.  Cardiac myxoma and large severe deficit; same for papillary fibroelastoma

Absolute exclusion, uncertain benefit or no evidence favoring

1.  acute intracranial hemorrhage on CT scan

2.  warfarin use with INR > 1.7

3.  therapeutic or prophylactic low molecular weight heparin dose within 24 hours

 or use of NOAC's (novel anticoagulants) within 48 hours  unless lab parameters as appropriate are assessed

4.  Major head trauma within three months

5.  Posttraumatic infarction that occurs in the hospital

6. Pericarditis with mild deficit

7.  LA or LV thrombus with expected mild or moderate disability

8.  Infective endocarditis

9.  Intracranial or intraspinal surgery within three months

10. Major GI or GU bleed within 21 days

11.  Arterial puncture of a noncompressible site within 7 days (eg. subclavian artery)

12. History of intracranial hemorrhage

13. Unruptured cerebral giant aneurysm

14.  Unruptured untreated cerebral AVM's unless benefit outweighs the heightened risk

15.  Intracranial neoplasm intraaxial

16.   End stage renal disease with elevated PTT

17.  Blood glucose initially < 50 or > 400 unless corrected

18.  Large area of hypoattenuation on initial CT scan

19.  Clinical suspicion of subarachnoid hemorrhage

20.  Suspected aortic arch dissection

21.  Suspected intracranial dissection

22.  Stroke due to sickle cell disease

Extended window:  Three to 4.5 hours

Not an exclusion

1.  Age > 80

2.  On warfarin with INR < 1.7

3.  Prior stroke and diabetes

alteplase can be considered if benefits outweigh risks

Absolute exclusion, uncertain benefit or no evidence favoring

1.  NIHSS > 25

2.  Wake up stroke with time last normal > 4.5 hours

3.  Use of neuroimaging to select patients with last time normal > 4.5 hours

Alteplase in strokes with NIHSS>25

Mazya MV, Lees KR, Collas D, et al.  IV thrombolysis in very severe and severe acute ischemic stroke. Results from the SITS/ISTR registry.  Neurology 2015; 85:20898-2106 (also editorial).

 

Authors study a large number of patients with severe strokes and find that iv alteplase does not affect their chances of developing a hemorrhage.  There also was no difference in treatment benefit compared to those with lower NIHSS scores.