Maximising Delivery of Thrombectomy

Transcription

1 Maximising Delivery of Thrombectomy Professor Gary Ford Chief Executive Officer, Oxford Academic Health Science Network Consultant Stroke Physician, Oxford University Hospitals Visiting Professor of Clinical Pharmacology, Oxford University Governing Body Fellow, Green Templeton College Joining Forces 2017, SW Stroke Event 15 June 2017

2 Suspected Stroke Clinical Assessment and Imaging Major Stroke TIA Minor Ischamic Stroke Non Stroke Ischaemic (87%) ICH (13%) HASU Thrombolysis, aspirin Thrombectomy HASU BP lowering Large vessel Small vessel occlusion (40%) occlusion (47%) Early assessment Acute Medical / Rapid discharge Neurology teams Dual anti-platelets Carotid revacularisation

3 Economic Burden of Stroke in the UK Cost M % Diagnosis costs Inpatient care costs Outpatient costs Outpatient drug costs Community care costs 2, Annual care cost total 4, Informal care costs total 2, Income lost due to mortality Income lost due to morbidity Productivity loss total 1, Benefit payments Total 8,979 Saka et al Age Ageing 2009

4 Acute Stroke Evidence Based Treatments % ischaemic stroke patients that benefit Prevention death/dependency per 100 treated Prevention death/dependency per 100 admitted Acute Stroke Unit 100% 5 5 Thrombolysis 0-3 hr Thrombolysis hr 15% % Thrombectomy 0-6 hr Aspirin 0-48 hr IPC Stockings 0-72 hr Hemicraniectomy 0-48 hr 10% % % 3 (death) % Adapted from Gilligan AK et al. Cerebrovascular Diseases 2005

5 Thrombectomy: a Disruptive Innovation Highly effective therapy for stroke due to large vessel occlusion, 10% acute stroke admissions potentially eligible 10,000 UK patients each year currently 500 treated Achieves recanalisation 80% patients current standard of care iv thrombolysis achieves 30% recanalisation rate Good outcome without significant disability increased from 26% to 46% Benefits are highly time dependent number needed to treat (NNT) to avoid disability fall from 3 at 2 hours to 15 at 6 hours Key requirements: 24/7 interventional neuroradiology team, supported by hyperacute stroke team CT angiography and reporting in hospitals admitting acute stroke patients Rapid ambulance transfer to thrombectomy centres Stent retriever

6 Stentriever Device - Solitaire

7 Number Needed to Treat HERMES Individual Patient Meta-Analysis Goyal et al, Lancet 2015 NNT for a very good outcome (mrs 0-2) 43% = 3-7 NNT for one-better mrs score at 90 days = 2-3

8 HERMES 5 trials (2015) Time is Brain

9 Thrombectomy Unanswered questions Does thrombectomy reduce 90 day mortality? Does thrombectomy increase sich with/without iv thrombolysis? Should we use advanced imaging to select patients in 4.5 hour time window? Does earlier delivery of thrombectomy outweigh delay in giving iv rtpa? Is iv rtpa of benefit if recanalisation is achieved with thrombectomy? In which groups of patients is thrombectomy cost effective?

10 Cost Effectiveness of Thrombectomy Cost per Quality-Adjusted Life Year (QALY) Alteplase within 3 hours Dominant Alteplase hours 4,451 Mechanical thrombectomy 3,857 Primary PCI for STEMI 9,241 Average for the NHS 13,000 Cancer Drugs Fund 68,326

11 The Number We Need to Treat 95,000 UK stroke admissions 1 in 10 eligible for thrombectomy Use of advanced imaging (MR perfusion/diffusion, CTP, CTA collateral scoring ) makes a small difference to overall numbers. Exclude 450 patients presenting <4.5 hours, but identifies 1,430 patients presenting later In England 8,500 cases p.a. NHS England specialist commissioning plans ,000 cases

12 Current Stroke Service Configuration Suspected stroke Patient FAST +ve HASU

13 Timelines for Drip and Ship Suspected stroke Patient FAST +ve Onset to scene 30 min Scene to Door 30 min (ambulance 1 leaves) Door to CT/CTA 20 min CT to tpa needle 10 min Needle to CTA read 20 min CTA to CSU accept 20 min Onset to accept 130 min Call to arrival ambulance 2 Door to CSU door Door to groin Groin to reperfusion Onset to reperfusion HASU 20 min 50 min 30 min 20 min 250 min

14 Quicker Drip and Ship Each minute saved in onset-to-treatment time granted on average 4.2 days of extra healthy life Meretoja et al, Neurology 2017 Suspected stroke Patient FAST +ve Onset to scene 30 min Scene to Door 25 min (ambulance 1 stays) Door to CT/CTA 10 min CT to tpa needle and CTA read (stroke phys) 5 min CTA read to CSU transfer 5 min (ambulance 1 leaves for CSU) HASU Door to CSU door 50 min Door to groin 20 min Groin to reperfusion 15 min Onset to reperfusion 160 min 90 min saving One year of healthy life

15 Point of Care Diagnostics for Stroke Purines

16 Improving CT Angiography Reading Stroke physicians and general radiologists need to be able to undertake initial scan reading Validated case archive of 50 hyperacute stroke CTA cases developed for a full day course on CTA interpretation. 44 trainees; 252 on call trainee reports Major errors; acute infarcts, intracranial haemorrhage, large vessel occlusion, dissection. significant ICA stenosis Minor errors; old strokes, <50% ICA stenosis, incidental findings such as small aneurysms, small meningioma, thoracic lymph nodes Reporting Error rate Before After Major 12 % 4 % p = Minor 25 % 30 % p = NS Cora et al. Clin Radiol 2017

17 Transferring CTA images Regional Teleradiology Networks iphone MiSTAR images

18 Direct to Mothership Each minute saved in onset-to-treatment time granted on average 4.2 days of extra healthy life Meretoja et al, Neurology 2017 Suspected stroke Patient FAST +ve Onset to scene 30 min Diagnosis on scene (RACE, point of care diagnostics Scene to CSU Door 60 min Door to CT/CTA CT to tpa needle CTA read CTA read to groin Groin to reperfusion Onset to reperfusion HASU 10 min 5 min 15 min 15 min 135 min 115 min saving 16 months of healthy life

19 Direct transfer of patients with likely large vessel occlusion stroke to thrombectomy centre; FAST + prehospital diagnostics + telemedicine specialist support Future Hyperacute Stroke Service Configuration? HASU

20 Developing a Regional Stroke Network delivering Thrombectomy Most focus is on creating interventional neuroradiology teams. Unlikely to be achieved without support of other specialties e.g. interventional cardiology. To achieve rapid treatment and maximise benefits, major changes needed in the clinical pathway: Imaging at spoke hospitals rapid delivery tpa, routine CT angiography and interpretation Ambulance transfer protocols Repatriation protocols Comprehensive stroke centres providing thrombectomy need to provide at least as good acute care as other stroke units in the region they serve