UNEXPECTED CAUSE(S) OF CEREBRAL MICROEMBOLISATION INVESTIGATED BY TRANSCRANIAL DOPPLER DUPLEX COLOUR...
Transcript of UNEXPECTED CAUSE(S) OF CEREBRAL MICROEMBOLISATION INVESTIGATED BY TRANSCRANIAL DOPPLER DUPLEX COLOUR...
UNEXPECTED CAUSE(S) OF CEREBRAL MICROEMBOLISATION INVESTIGATED BY
TRANSCRANIAL DOPPLER DUPLEX COLOUR SONOGRAPHY
Muriel SPRYNGERCardiology-AngiologyCHU Sart Tilman, Liège
BSTH, November the 27th, 2009
CASE REPORT
• 72-year old hypertensive man • december 2008 : right internal carotid thrombotic
occlusion with left hemispheral stroke + 80% left internal carotid stenosis
• january 2009 : stenting of the left internal carotid• october 2009 : admitted for suspected worsening
left hemiparesia and cerebral confusion• Medication : clopidogrel + simvastatine
CAROTID ULTRASOUND
– Right internal carotid occlusion
– Moderate narrowing at the distal part of the left internal carotid stent
CEREBRAL MRI
• bilateral ischemic parietal sequellae
TEE + CONTRAST
• multiple irregular aortic plaques
• interatrial septal aneurysm + right-to-left interatrial shunt through a patent foramen ovale (PFO)
CONTRAST TCD
• Saline contrast TCD with injection of 10 cc of 9°/°° saline infusion in the right forearm
• Bilateral middle cerebral artery recording
CONTRAST TCD : middle cerebral artery
Microembolic signals (MES) were recorded on both sides
DISCUSSION
CARDIOEMBOLIC STROKE• approximately 20% of strokes are cardioembolic (40% in younger
populations)• atrial fibrillation• valvular heart disease• endocarditis• mitral valve prolapse• prosthetic heart valves,• recent myocardial infarction (0,8% strokes, 1-2%/y),• intracardiac thrombus,• dilated cardiomyopathy• sick sinus syndrome, • patent foramen ovale,• hypokinetic/akinetic left ventricular segment• calcification of the mitral valve• cardiac surgical procedures : 1-7% perioperative stroke
TEE• « gold standard » for the
detection of :– PFO :
• < 20 bubbles : small shunt• > 20 bubbles : large shunt
– Atrial septal aneurysm
• PFO is found in 25% of the healthy population
• PFO + aneurysm : dangerous association?
• 15% of patients who underwent PFO closure had AF detected 3 to 6 months afterwards. PFO closure patients warrant antiplatelet medication at a minimum
CLINICAL RELEVANCE OF TCD AND TEE IN PFO DETECTION
• cTEE = gold standard ? Semi-invasive
• 90% concordance• cTCD :cTCD :
– 20’’ after 1st MB 20’’ after 1st MB – at rest, more sensitive than at rest, more sensitive than
cTEEcTEE– sensitivity 97%, specificity sensitivity 97%, specificity
78%78%– Semi-quantitative Semi-quantitative
(« curtain »)(« curtain »)– Intrapulmonary shuntIntrapulmonary shunt
Bilateral MES
• despite or because of right internal carotid occlusion
• Origins ?– Venous– Aortic– Supra-aortic
(heterolateral carotid)– Cardiac (AF)
CONCLUSION
• In case of right-to-left shunts, cTCD can complete cTEE : – better sensitivity– Semi-quantitative method
• cTCD can also detect potential ME in unexpected cerebral areas and/or explain unexpected strokes.
CONCLUSION
• Contrast-TCD can diagnose large PFO
PFO - CLOSING DEVICE ?• The data supporting risk factors (ie, atrial
septal aneurysm or large PFO) are weak.
• Right-to-left shunting may not be the only possible mechanism for stroke ? More AF.
• High-level evidence for PFO management is desperately needed.
TCD and PFO Contrast Transcranial Doppler Can Diagnose Large Patent Foramen
Ovale
• Small PFO : 19 MES/78 (24%)
• Large PFO : 27 MES/27 (100%)
• No PFO : 3 MES/216• 2 MES is the cutoff to
predict large PFO : – Sensitivity : 96,3%– Specificity : 96.8%– Accuracy : 96.9%
When two or more MES were determined by c-TCD, large PFO could be accurately diagnosed.