The Neurologist as the Gatekeeper of PFO Closure in the US: What is Cryptogenic Stroke and When Do Neurologists Think PFO Closure Is Needed? David E. Thaler, MD, PhD Chairman, Department of Neurology Tufts University School of Medicine Boston, MA
The Neurologist as the
Gatekeeper of PFO
Closure in the US: What
is Cryptogenic Stroke and
When Do Neurologists
Think PFO Closure Is
Needed?
David E. Thaler, MD, PhD
Chairman, Department of Neurology
Tufts University School of Medicine
Boston, MA
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Pt M – 30 y/o F with BRAO
16hrs after airplane flight and PFO
30 mins s/p apraclonidine drops
Final diagnosis: Left ICA dissection and retinal embolism
… and incidental PFO
What is the underlying mechanism?
“Stroke is an observation not a
diagnosis”
Common mechanisms of cerebral ischemia
• “Small vessel disease” - lipohyalinosis
• Embolism
– Artery-to-artery (carotid, aorta, other)
– Cardiac source
– Paradoxical
• Decreased perfusion through a fixed stenosis
Other causes of cerebral ischemia
• Vasculitis
• Collagen vascular diseases: isolated angiitis of the CNS, temporal (giant cell) arteritis, polyarteritis nodosa, Wegener's granulomatosis, Takayasu's arteritis, syphilis
• Meningitis: tuberculosis, fungi, syphilis, bacteria, herpes zoster
• Arterial dissection: carotid, vertebral, basal intracranial arteries
• Hematologic disorders: polycythemia, thrombocytosis, thrombotic thrombocytopenic purpura, disseminated intravascular coagulation, dysproteinemias, hemoglobinopathies (sickle cell disease)
• Miscellaneous: cocaine, amphetamines, moyamoya disease, fibromuscular dysplasia, CADASIL
• Hypercoagulable states: secondary to systemic disease, carcinoma (especially pancreatic), eclampsia, oral contraceptives, lupus, factor C or S deficiency, factor V mutation, etc.
• Vasospasm: following subarachnoid hemorrhage
• Reversible cerebral vasoconstriction: idiopathic, eclampsia, trauma
• Venous: Dehydration, pericranial infection, postpartum and postoperative states, systemic cancer
Stroke mimics and chameleons
Lancet Neurol 2011, 10: 550-60
Stroke mimics
• Migraine
• Seizure
• Subdural hematoma
• Tumor
• Syncope
• Cardiac arrhythmia
• Panic attack
• Hypoglycemia
• Demyelinating disease
• Amyloid angiopathy
• Brain abscess
• Encephalitis
Stroke chameleons
Condition Prevalence
Altered mental status 31%
Syncope 16%
Hypertensive emergency 13%
Systemic infection 11%
Suspected acute coronary syndrome 10%
Other (seizure, peripheral vertigo, cord compression,
myasthenia gravis, Bell palsy, migraine, hypoglycemia)
20%
J Stroke Cerebrovasc Dis 2014 23: 374-378
Do I know what “neurologists” think?
Authors by specialty
Neurology Internal Med/Cardiology Other
Ovbiagele Kernan (IM) Heck: Radiology
Chimowitz Black (IM) Mitchell: Nursing
Fisher Bravata(IM) Richardson: Statistician
Furie Ezekowitz (C) Wilson: Neurosurgery
Johnston Fang (IM) Hepburn-Smith: Nursing
Kasner Rich (C) Mack: Neurosurgery
Kittner Panagos: ED
Schwamm
Gorman
Rabinstein
n=10 n=6 n=7
Classification of Recommendations and
Level of Evidence
2011
2014
Classification of Recommendations and
Level of Evidence
2011
2014
Recommendation should be changed
• Class III definition changed
• Committee erred in interpreting “negative trials”
• Evidence using the committee’s own words support at least IIb
It may never come to this...
CARDIOLOGIST NEUROLOGIST
Slide courtesy of Vincent Thijs, MD
Suggestions
1. Neurologists and cardiologists must collaborate
2. Involve neurologists in the diagnosis of stroke
3. Exclude other common “cryptogenic” causes: PAF, aortic atheroma, lacunes
4. Not every dizzy spell is a TIA
5. Continue aggressive risk factor modification after closure
6. Continue antithrombotic medication after closure
7. Involve patients in the decision making
8. Intersociety position statements