Faulder weighs in on intraluminal therapy in acute stroke management.

1. Mechanical thrombectomy and
the future of stroke
Dr Ken Faulder
Interventional Neuroradiologist
Westmead and Royal North Shore Hospitals

2. N/A
IncidenceRate(%)
IV-rtPAPlacebo
NINDS* (National Institute of Neurological Disorders and
Stroke rt-PA Stroke Study Group)
*AJNR 30:859-75: May 2009
NINDS demonstrated
that IV-tPA is
safe and more effective
than Placebo in the
0-3 hour window.
28.0%
24.0%
1.0%
39.0%
21.0%
7.0%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
Recanalization GoodOutcome(mRS0-1) Mortality SymptomaticICH

3. N/A
IncidenceRate(%)
IV-rtPAPlacebo
ECASS III (European Cooperative Acute Stroke
Study)
N Engl J Med. 2008 Sep 25;359(13):1317-29.
ECASS III extended the
window of care for IV tPA
treatment to 4.5 hours.
49.2%
8.4%
0.2%
52.4%
7.7%
2.4%
0%
10%
20%
30%
40%
50%
60%
Recanalization GoodOutcome Mortality SymptomaticICH

4. IV tPA – Recanalization at One Hour (angiographic
data)
Del Zoppo et al.,Ann Neurol 1993
•
IV-rtPA recanalization rates for large vessel occlusions in
comparison to smaller vessel occlusions is lower.
31%
8%
24%
35%
40%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
All ICA MCAStem MCADivsn MCABranch
%Recanalized

5. Effect of site of occlusion on clinical
outcome
 Published June 21, 2012 as 10.3174/ajnr.A3149

6.  Strokes treated in NINDS trial in fact a
heterogenous group
 Perforator, M3, M2, M1, ICA
 TPA does not work in long M1 or ICA
occlusions,TPA wrong treatment and
prevents or delays correct triage to IA
treatment

7. REVASCULARIZATION AND GOOD OUTCOME
Rha Meta-analysis
Recanalized: 58% good
outcome
Non-recanalized: 25%
good outcome
53 studies, 2066 patients
Morbidity and mortality at 3 months
Strong association with recanalisation & good outcome
Recanalisation is appropriate biomarker of therapeutic activity
Stroke 2007

8. Variability and reversibility of focal
cerebral ischaemia in
unanesthetized monkeys
Cromwell RM et al
Stroke lab, Uni of Massachusetts
Neurology October 1981
31(10):1295-1302
‘neurologic improvement was
common after the release of
occlusion.
…frequent with 30-min and 4-
hour occlusions
…was observed even after 16
hours’

9. Time is Brain - Quantified
 1.9 Million Neurons lost every minute
 Calculations on growth function of a
‘typical’ large vessel ischaemic stroke
 Used ‘linear growth function’ to
calculate neuronal loss over time
 Personal observation is that if there is
recanalization, final infarct refects core
volume at time of perfusion, raises
question whether infarct growth linear
J Saver - Stroke 2005

10. 70 yo man, acute left hemispheric stroke,
presents at 2 hours
Is this patient better off if given TPA?

13. Poor outcome in patients defined as malignant perfusion had poor outcome (100%) vs non
malignant scans (7.1%)
Stroke 2012;43:0-0

14. 72 yo woman dense left hemiplegia 4 hrs
post onset, NIHSS 12

17.  The independent predictive utility of
computed tomography angiographic
collateral status in acute ischaemic
stroke
Miteff F et al
Brain 2009:132:2231-2238

18. Evolution of technique
 Early days of IA lysis, patients treated with
intra-arterial rTPA or Urokinase
 ProAct II, clinical outcomes promising but
concern over incidence of symptomatic
intracerebral haemorrhage ~10%
 Early mechanical devices initially
promising but difficult to use, long
procedures and 70-80% recannalization

19. Evolution of technique
 IMS III
◦ Trial comparing IV thrombolysis and
combined IV thrombolysis and intraarterial
clot retrieval
◦ Early 2012, study stopped early because of
futility
◦ Several criticisms of study design, most
importantly 1st generation devices, Merci,
Ekos
◦ Secondly, time delay to institution of IA

24. AJNR Am J Neuroradiol. 2011 Jun-Jul;32(6):1078-81. doi: 10.3174/ajnr.A2447. Epub 2011
Apr 14.
Mechanical thrombectomy with a self-expanding retrievable
intracranial stent (Solitaire AB): experience in 26 patients with acute
cerebral artery occlusion.
Miteff F, Faulder KC, Goh AC, Steinfort BS, Sue C, Harrington TJ.
26 consecutive stroke patients treated with solitaire embolectomy device
94% recannalization
56% good clinical outcome mRS 0-2 at 90 days
20% good outcome in basilar occlusions

25.  Solitaire fow restoration device versus the Merci
Retriever in patients with acute ischaemic stroke
(SWIFT): a randomised, parallel-group, non-
inferiority trial – Lancet August 2012
 Study designed to show equivalence of newer
solitaire device with Merci retriever
 55 pts treated with Merci device, 58 with Solitaire
 Good clinical outcome at 90 days
 Merci 33%, Solitaire 58%
Newer Mechanical Devices

26. Newer Mechanical Devices
 STAR trial (incl RNSH)
◦ Single arm international multicentre study
◦ Failed IV or IV ineligible, large vessel occlusion
◦ Revascularization 94.7%
◦ ICH 1.5%
◦ Mortality 6.9%
◦ mRS 0-2 at 90 days 57.9%
 Ninds
ICH 7%, Mortality 21%, Good outcome 39%

27. Intra-arterial Treatment Future
 Clearly place for IV and IA treatment
 Effectiveness dependent on site of
occlusion and time to treatment
 Future trial design aimed at
◦ better patient selection, CTA and perfusion
◦ IV ineligible or predicted low success rate
◦ IV ineligible patients
 Success in stroke treatment will depend
upon correct treatment pathways and
protocols for urgent intervention