transcranial doppler is superior to tee for detection of...
TRANSCRIPT
Transcranial Doppler is superior to TEE for detection of Patent Foramen Ovale
Joshua Tobe, Chrysi Bogiatzi, Claudio Munoz, Arturo Tamayo, J. David Spence
Stroke Prevention & Atherosclerosis Research Centre,
Robarts Research Institute, Western University,
London, Canada
[email protected] http://www.robarts.ca/sparc
Disclosures
No relevant disclosures Grants from NIH, CIHR, HSF Canada Support for research from Pfizer Speaker’s fees from Merck, AstraZeneca, Boehringer-Ingelheim Consulting fees from Boehringer-Ingelheim, Novartis Contract research with Servier Canada, Pfizer, Bristol-Meyers Squibb, AGA and NMT Interest in Vascularis.com
Paradoxical embolism
Hankinson and Hutcheson 1978
4% of ischemic stroke
Patching sounds like a good idea, but…
PFO Closure: Statistical power issue • 25% of the population have a PFO • 4-5.5% of strokes are due to paradoxical
embolism1,2 • ~ 80% of PFO’s in stroke patients are incidental • ~ 50% incidental in cryptogenic stroke3
1. Hutchinson,EC and Acheson, EJ. Strokes: natural history, pathology and surgical treatment. (4). 1975. London, W.B. Saunders.
2. Ozdemir AO, et al. J Neurol Sci 2008; 275: 121–127 3. Kent D, Thaler D. Stroke 2010;
Complications of percutaneous closure
• Atrial fibrillation
• Embolization of the device
– Aortic valve occlusion
– Femoral artery occlusion
• Thrombus on the device
Courtesy of Dr. Bob Kiaii and Dr. Bryan Dias
Surgical removal of Cardioseal device with thrombus 6 years after closure
Stroke in 2000 age 54; closure 2003; 2008 thrombus on device 6 months intensive anticoagulation Device removed 2009
PFO closure in stroke patients: a definite maybe
1. Kitsios GD, et al. Stroke 2013; 44:2640-2643.
2.Ntaios G et al.. Int. J Cardiol 2013; 169:101-105.
So: We need to identify which PFO patients are more likely to have
paradoxical embolism
Clinical Clues to Paradoxical Embolism 5.5% of new TIA/stroke patients Suspect if: • Young patient without other cause • Dyspnoea*, tachycardia at onset • ↓ O2, ↓ pCO2 • Loud P2, Pulmonic regurge • Loss of consciousness at onset of carotid stroke • Long ride in a car, airplane or sitting at computer* • Swollen leg, previous DVT, varicose veins* • Pulmonary emboli in past* • Valsalva maneuver* • Waking up with stroke* • Sleep apnea* *p<0.05 Ozdemir AO, et al. J Neurol Sci 2008; 275: 121–127
PFO morphology and stroke risk
Small early studies suggested features of
“high-risk PFO”:
• Larger shunt, septal mobility1
• Atrial septal aneurysm2
1. De Castro S et al. Stroke 2000;31:2407-2413. 2. Mas J-L et al N Engl J Med 2001; 345:1740-6.
Recent large studies: septal aneurysm/mobility do not predict events
1. Wessler B et al. Circ. Cardiovasc. Imaging 2013 Nov 8. [Epub ahead of print]. 2. Di Tullio MR et al. J Am Coll Cardiol 2013; 62:35-41.
• ROPE study1
• combined analysis of 1294 cases from 12 observational databases
• Northern Manhattan Study2 • Population-based study of 1100
participants, 14.9% with PFO, followed for 11 years
Better tools needed
“Additional tools to describe PFOs may be useful in helping to determine whether an observed PFO is incidental or pathogenically related to (cryptogenic stroke).”1
1. Di Tullio MR et al. J Am Coll Cardiol 2013; 62:35-41.
TCD more sensitive than TEE1
• Inadequate Valsalva2
• ? Eustachian valve3
• One small study (n=59) suggested shunt grade predicted events4
1.Bogousslavsky J et al. Neurology 1996; 46:1301-1305. 2. Rodrigues AC et al. J Am Soc Echocardiogr. 2013; 26:1337-1343. 3. Anzola GP. Stroke 2004; 35:e137. 4. Anzola,GP et al. Eur J Neurol 2003; 10:129-135.
Our study
• Patients referred to the Urgent TIA Clinic between 2000 and 2013
• Cryptogenic stroke • Suspected of having paradoxical embolism • All had TCD saline studies (TCDSS)
Our study
• 340 patients with RLS confirmed on TCDSS • 61.5% female, age 53 + 14 years • Median followup 420 days, max 3240 days • 85 had a recurrent ischemic stroke or TIA • 280 cases had TEE available • Atrial septal aneurysm or mobile septum in
54 cases (19.3%) • Echo failed to show RLS in 43 (15.4%)
TCD shunt grades
• Grade 0: no microemboli detected • Grade I: 1-10 microemboli • Grade II: 11-30 microemboli • Grade III: 31-100 microemboli • Grade IV:101-300 microemboli • Grade V: > 300 microemboli
Spencer MP et al. J Neuroimaging 2004; 14:342-349.
Bubbles are not subtle; they are definite
Before injection Without Valsalva maneuver
With Valsalva maneuver Ozdemir AO, et al. J Neurol Sci 2008; 275: 121–127
Besides the visual output and bubble count, there is an audio signal that is unmistakeable – on video clip at end
TCD better than Echocardiogram Echo missed 15% of right-to-left shunts
TCD Shunt Grade
% of shunts Missed by Echo
1 45.5% 2 32.2% 3 13.3% 4 7.1% 5 4.7%
Echo misses even large shunts n = 54/280
25% Grade 3 or higher
Survival free of stroke/TIA by TCD shunt grade
Survival free of stroke/TIA by RLS on TEE
Survival free of stroke/TIA by septal aneurysm/mobility
Conclusions
• TCDSS better for diagnosis of PFO • TCDSS better for risk stratification in PFO • TEE still needed for diagnosis of other
cardioembolic sources such as: • Left atrial appendage thrombus • Left atrial myxoma • Ventricular aneurysm, dyskinesia • Valve problems
• TCD and TEE are complementary
Acknowledgements 3-D Ultrasound technology Genetics Drs. Aaron Fenster, Grace Parraga Dr. Rob Hegele Measurements Lab Manager 2-D : Maria DiCicco RVT Tisha Mabb 3-D: Craig Ainsworth, CAIN Anthony Landry, Chris Blake, Dr. J-C Tardif et al. Micaela Egger, Christiane Mallet, Silvia Riccio Dr. Rob Beanlands Bernard Chiu, Shayna McKay, Adam Krasinsky Dr. Myra Cocker Ulcers Dr. Vadim Beletsky, Jeremy Mason, Amin Madani
Plaque composition Jeremy Mason, Dr. Joseph Awad, Mariya Kuk TCD Studies Dr. Arturo Tamayo Stroke Subtypes MRI Dr. Claudio Munoz Chrysi Bogiatzi Dr. Brian Rutt Scanning Dr. Dan Hackam PET/CT/MRI Maria DiCicco RVT Dr. Frank Prato Janine Desroches RVT Dr. Ting Lee
http://www.imaging.robarts.ca/SPARC/ [email protected]
Grade V shunt