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Endovascular Neurointervention in Cerebral Ischemia Beyond Thrombolytics

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Endovascular Neurointervention in Cerebral Ischemia Beyond Thrombolytics Endovascular Neurointervention in Cerebral Ischemia Beyond Thrombolytics Curtis A. Given II, MD Co-Director, Neurointerventional Services Baptist Physician Lexington 72 y/o female with a recent diagnosis of paroxysmal atrial fibrillation developed right hemiparesis and global aphasia while at interstate “rest stop”. Patient was taken to regional medical facility (Corbin Baptist Regional) within 1 ½ hours of onset of symptoms. NIHSS was 16 and head CT was normal. IV-tPA was administered by the Emergency room physician and the patient was transferred to UK. Upon arrival to UK, the patient was hemiplegic with global aphasia and NIHSS was 22. Repeat head CT was normal. Patient was immediately taken to the Angiography suite First pass with Merci retriever was performed at approximately 6 hours after the onset of symptoms Two passes of the Merci retriever resultant in complete recanalization of the left middle cerebral artery The patient began to have purposeful movement of her right arm and leg Immediately after the procedure. MRI of the head on the following day revealed only a few small infarcts. She was discharged home, independent and without the need for rehabilitation, and an NIHSS of 0. Stroke • Impact – Every 45 seconds someone in the U.S. has a stroke – Stroke is #3 cause of death – Stroke is #1 cause of adult disability – Approximately 87% ischemic • Limited treatment options – Intravenous lytic • Limitation: must be administered within 3 hours of stroke onset • Estimated <5% of stroke patients receive IV lytic – Mechanical revascularization with Merci® and Penumbra ® Retrieval Systems • Option beyond 3 hour window, and for patients who are ineligible for or who fail IV t-PA therapy Time Window for Potential Stroke Treatments Time Window 0-4.5 hrs 0-6 hrs >6 hrs ‡ Options • IV tPA • Merci • Merci • Merci* • Penumbra • Penumbra • Penumbra* •Solitaire •Solitaire •Solitaire • IA Lytic† * 0-3 hours in patients who are contraindicated for IV tPA or who fail IV tPA therapy. † Not FDA approved. ‡ The MERCI and Multi MERCI trials evaluated patients up to 8 hours Patient Selection for Intra-arterial Therapy . Generally patients with symptoms of large vessel occlusion (NIHSS > 8) . No changes of large infarct (less than 1/3 of vascular territory) on CT or DWI . No hemorrhage on CT . < 8 hours since “last seen normal” OR significant tissue “at-risk/penumbra” on Perfusion imaging . Any patient with basilar occlusion . Large vessel occlusion on CTA/MRA Contraindications to IA Thrombolysis • CT-documented hemorrhage or significant mass effect • Fibrinogen < 120 mg* • Platelet count < 80,000* • Active internal bleeding or recent surgery (<10 days)* • Prior allergic reaction to r-tPA* • BP > 200 systolic or >120 diastolic despite medical therapy • No clot on angiography * Not contraindication to mechanical thrombectomy What about patients presenting after 8 hours or “wake up” strokes? • Significant problem, particularly in patients with an unknown time to onset (“wake up” strokes). • Traditionally, these patients offered only supportive measures • 50% of patients may have a persistent ischemic penumbra at 24 hrs. Slide borrowed from Dr. Lev’s ASNR presentation 2008 TTP > 6 sec rCBF 60% rCBV 110% Trials of Intra-arterial Thrombolytic Agents PROACT II Furlan A. et al. JAMA 282:2003, 1999 • Randomized open-label trial of prourokinase (r-pro-UK) 9 mg with heparin vs systemic heparin in patients with middle cerebral artery occlusions within 6 hours of onset. • Pro-urokinase delivered over 2 hours by microcatheter into the middle cerebral artery at the face of the clot. • Mechanical clot disruption was not permitted. • Final angiogram at 2 hours in both groups. Pre Interim Post – 20 mg IA r-tPA Endovascular Thrombectomy of Cerebral Vessels • Merci Retriever • First surgical device cleared by the FDA for acute ischemic stroke patients • Restores blood flow to the brain by physically removing thrombus from the occluded precerebral or cerebral vessel Candidates for Merci Therapy Only used for patients with ischemic stroke, not hemorrhagic stroke • Patients who are ineligible for treatment with intravenous tPA : – outside 3-4.5 hour window – other clinical factors, eg. recent surgery, long-term current use of anticoagulants for atrial fibrillation, allergy to t-PA • Patients who have failed (or not responding to) prior intravenous t-PA therapy Specialized Devices • Merci® Retriever • Merci® Microcatheter • Merci® Balloon Guide Catheter Endovascular thrombectomy devices were cleared by the FDA in August 2004 Merci Registry Background The Merci Registry is a Post-Market study designed to capture “real-world” interventional treatment of acute stroke with the Merci Retriever system, unconstrained from the “trial” environment Merci Registry The Largest, Prospective Multi-Center Study of Mechanical Embolectomy for AIS • Prospective, multi-center study (36 centers) • 1,000 patients enrolled in 3 years – Interim results presented at ISC 2010 analyzed 625 patients • Inclusion criteria: procedure must have included a Merci Retriever and patient informed consent • No exclusion criteria • Interim results validated MERCI and Multi MERCI results in a much larger unconstrained cohort Revasc Rates by Final TICI Score Merci Registry – Interim Analysis Good Outcomes by Final TICI Score Merci Registry – Interim Analysis Good Outcomes defined as mRS=0-2 at 90 days Penumbra Thrombectomy System The Penumbra System is designed to revascularize large vessel occlusions in the intracranial circulation. The Penumbra System uses a unique microcatheter and SeparatorTM based thrombus debulking approach to intracranial vessel revascularization. The Penumbra advantages are: •Proximal working position •Continuous Aspiration •Variable sizing for variable anatomy So What’s Next? • “Stent-trievers” • Solitaire® and Trevo® • Allow for faster and higher recanalization rates, with fewer device deployments (‘passes’), and improved clinical outcomes relative to Trevo™ Merci Retrieve with Confidence Merci Retriever ® Clinical History The Solitaire™ FR device Retrospective data demonstrates higher angiographic and neurological outcomes when compared to these Merci® registries. **TICI 2a-3 classification was used Merci® Competitive Messages: 1. 2.5x improvement in Recanalization 2. 1.7x improvement in neurological outcomes 3. 55% reduction in mortality Solitaire™ FR revascularization device vs. The Concentric ® Merci® Retriever1 (SWIFT Study) (Core Lab) 79 yo WM awoke and walked to bathroom at 9am, wife heard loud noise and went to find husband lying in the floor of bathroom, aphasic and right sided hemiplegic. Transferred to CBH and received full-dose tPA at 12pm (approx. 3hrs after symptom onset). Initial NIHSS was 24 upon arrival to CBH. CT Perfusion scan shows large area of ischemia in left MCA territory consistent with large vessel occlusion, sent for possible thrombectomy. Partial flow restoration with Solitaire at 130pm (4.5 hrs after sx onset) Two passes with 4x20mm Solitaire The next day, the patient had regained anti-gravity strength in the right upper and lower extremities and significant improvement in speech (mild-moderate residual expressive aphasia). 24 hr NIHSS had improved to 6 (initial was 24). TTD rCBV 24 hr CT TREVO 2 Thrombectomy REvascularization of large Vessel Occlusions in acute ischemic stroke . Randomized, prospectively controlled, multi-center, non- inferiority IDE study of arterial revascularization in acute ischemic stroke patients . Up to 25 sites (at least 20 sites in North America) – 1st and only site in Kentucky . 178 patients, with a planned interim analysis at 120 . Randomized 1:1, with test arm using the Trevo device, the control arm using the Merci device 27 yo male with history of eosinophilic myocarditis and dilated cardiomyopathy, presented with acute onset of left facial droop, left hemiplegia, dysarthria and gaze defect. Initial NIHSS=16. He was antiocoagulated for his cardiomyopathy and prior stroke (prior full recovery) with a PT/INR or 26.7/2.3 (therapeutic anticoagulation). Given anticoagulation, he was not a candidate for thrombolytic therapy (tPA). Was evaluated and treated my partner Christian Ramsey. rCBV rCBV rCBV TTD TTD TTD “relative cerebral “relative cerebral “relative cerebral “time-to-drain” “time-to-drain” “time-to-drain” blood volume” blood volume” blood volume” rCBV rCBV rCBV TTD TTD TTD “relative cerebral “relative cerebral “relative cerebral “time-to-drain” “time-to-drain” “time-to-drain” blood volume” blood volume” blood volume” 4x20mm Solitaire The next day, the patient had regained full strength in the left upper and lower extremities and with only minimal residual facial droop. 24 hr NIHSS had improved to 1 (initial was 16). TTD “time-to-drain” 57 yo BF with “wake up” stroke manifesting as slurred speech and right arm/leg paralysis, resulting in fall to floor upon getting out of bed. PMH significant for non-ischemic cardiomyopathy with pacemaker (EF 30-35%), type II DM, and dyslipidemia (not on statin therapy). Initial NIHSS was 8 in the ED, and was NIHSS of 11 prior to procedure. rCBV “relative cerebral blood volume” 4 passes with the Solitaire and 6mg of IA tPA into the left MCA TTD TTD Initial CT Perfusion F/u CT Perfusion 3 days later At the time of transfer to rehab, she regained full strength in her right lower extremity and her speech had significantly improved. Unfortunately she was still plegic in the right upper extremity. 334 patients received “endovascular” therapy . “Endovascular” Treatment after IV t-PA
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