1. health and fitness
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Cardiovasc Intervent Radiol (2012) 35:1029–1035
DOI 10.1007/s00270-012-0438-5
CLINICAL INVESTIGATION
ARTERIAL INTERVENTIONS
Endovascular Acute Stroke Treatment Performed by Vascular
Interventional Radiologists: Is It Safe and Efficacious?
Lars Fjetland • Sumit Roy • Kathinka D. Kurz
Jan Petter Larsen • Martin W. Kurz
•
Received: 17 April 2012 / Accepted: 30 May 2012 / Published online: 30 June 2012
Ó Springer Science+Business Media, LLC and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) 2012
Abstract
Purpose To evaluate the safety and efficacy of neurointerventional procedures in acute stroke patients performed
by a team of vascular interventional radiologists in close
cooperation with diagnostic neuroradiologists and stroke
neurologists and to compare the results with those of previous reports from centres with specialised interventional
neuroradiologists.
Material and Methods A total of 39 patients with acute
ischemic stroke due to large-vessel occlusion not
responding to or not eligible for intravenous thrombolysis
were treated with either intra-arterial thrombolysis or
mechanical thrombectomy (Penumbra System or solitaire
FR thrombectomy system, respectively) and included in
our prospective study. Outcomes were measured using the
modified Rankin scale after 90 days, and recanalization
was assessed by thrombolysis using the myocardial
infarction score.
Results Mean patient age was 68.3 ± 14.2 years; the
average National Institutes of Health Stroke Scale score at
hospital admission was 17.2 (SD = 6.2 [n = 38]). Successful recanalization was achieved in 74.4 % of patients.
Median time from clinical onset to recanalization was 5 h
L. Fjetland (&) S. Roy K. D. Kurz
Department of Radiology, Stavanger University Hospital,
4068 Stavanger, Norway
e-mail: [email protected]
L. Fjetland J. P. Larsen M. W. Kurz
The Norwegian Centre for Movement Disorders, Stavanger
University Hospital, 4068 Stavanger, Norway
J. P. Larsen M. W. Kurz
Department of Neurology, Stavanger University Hospital,
4068 Stavanger, Norway
11 min. Procedure-related complications occurred in 5 %
of patients, and 7.5 % had a symptomatic intracerebral
hemorrhage. Of the patients, 22.5 % died within the first 90
postprocedural days, 5 % of these from cerebral causes.
Patients who were successfully recanalized had a clinical
better outcome at follow-up than those in whom treatment
failed. Of the patients, 35.9 % had an mRS score B2 after
90 days.
Conclusion Our results are in line with those in the
published literature and show that a treatment strategy with
general interventional radiologists performing neurointerventional procedures in acute stroke patients with large
vessel occlusions can be achieved to the benefit of patients.
Keywords Neurointerventions Endovascular treatment Thrombectomy Thrombolysis Stroke therapy
Introduction
Stroke is one of the leading causes of morbidity and
mortality worldwide [1–3]. Ischemic stroke accounts for
75–85 % of all strokes [4–6]. Since the publication of the
seminal National Institutes of Neurological Disorders and
Stroke study in 1995 [7], the clinical approach to acute
ischemic stroke has undergone a radical change. The
condition is now considered a medical emergency that
demands prompt therapeutic intervention. Based on the
results of multiple trials, intravenous (IV) thrombolysis
with recombinant tissue-plasminogen activator (rt-PA)
during the first hours after the onset of symptoms has been
established as the first line of treatment for this condition
[8–11].
IV thrombolysis is, however, not particularly effective
when the culprit lesion is an occlusion of a relatively large
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artery [12, 13]. In addition, the narrow time window
implies that only a minority of patients with acute stroke
can be selected for such treatment. Alternative treatments,
such as intra-arterial (IA) thrombolysis B6 h after symptom onset or mechanical thrombectomy devices B8 h after
symptom onset, have been studied with encouraging
results. Reported reperfusion rates with these approaches
vary between 69.5 % [14] and 100 % [15, 16]. Clinical
outcome at 90 days compared with IV thrombolysis has
been found to be superior [17, 18].
These reports come mostly from high-volume stroke
centres, and the treatment is performed by interventional
neuroradiologists. The availability of these centres and
specialists is limited and not sufficient to give the population an equal offer of invasive stroke treatment [19]. In
this study, we report the experience of a university medical
centre that serves a population of approximately 330,000
inhabitants where invasive reperfusion is performed by
vascular interventional radiologists in close cooperation
with diagnostic neuroradiologists and stroke neurologists.
The objective was to study the safety and efficacy of this
way of organizing treatment by evaluating the performed
procedures and comparing the results with those of previous reports.
Methods
Patients
From May 2009 to October 2011, all patients admitted to
our medical centre within 8 hours of onset of symptoms of
acute stroke were considered for inclusion in the study. All
patients underwent cerebral computed tomography (CT).
The initial examination included unenhanced CT, perfusion
CT, and CT angiography. Patients with an occlusion of the
M1 segment of the middle cerebral artery (MCA), internal
carotid artery (ICA), or basilar artery (BA) on CT angiography, and with no signs of intracranial hemorrhage
(ICH) or distinct demarcation of an infarction greater than
one third of the vessel territory, were considered potential
candidates for IA thrombolysis within 6 h and mechanical
thrombectomy within 8 h of symptom onset.
Patients with a central arterial occlusion eligible for
thrombolysis who arrived at the hospital within 4.5 h from
ischemic symptom onset were pretreated with IV rt-PA
(Actilyse; Boehringer Ingelheim, Germany). These patients
were transferred with ongoing rt-PA infusion to the angiography suite for interventional treatment. Those patients
arriving later than 4.5 h after symptom onset were
transferred directly to the interventional laboratory. The
decision about endovascular treatment was made by a team
consisting of the treating stroke neurologist, a vascular
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L. Fjetland et al.: Endovascular Acute Stroke Treatment
interventional radiologist, and a diagnostic neuroradiologist.
This decision was based on clinical criteria, results of the
initial CT examination, and response to IV thrombolytic
therapy by patients eligible for such treatment. No patients
were excluded due to advanced age, recent surgery, or
increased INR. Patients were included in the study after
angiographic confirmation of large cerebral vessel
occlusion.
Ethics
Before treatment, informed consent was obtained from
either the patient or a legal representative. This study was
approved by the local Ethical Committee.
Revascularization Procedures
Endovascular treatment was performed by five experienced
vascular interventional radiologists. All procedures were
performed in a general angiography suite equipped with a
floor-mounted single-plane C-arm for digital angiography
(Siemens Artis zee; Siemens, Erlangen, Germany).
During the last few years, there has been rapid technological development in the field of invasive stroke treatment, and many new reperfusion techniques have been
designed and evaluated in clinical trials [20, 21]. According to this new data and to offer our patients state-of-the-art
treatment, we changed our treatment from IA thrombolysis
to thrombectomy devices during this study. All patients
treated, regardless of technique and device, were included
in the study.
We adopted a standard technique for femoral arterial
puncture and performed standardized access using 6F
guiding sheaths (Strada; St. Jude Medical Inc, St. Paul, MN,
USA) and 6F guiding catheters (Envoy; Cordis Inc, Miami
Lakes, FL, USA) or Neuron catheters (Penumbra Inc,
Alameda, CA, USA) to, respectively, the common carotid
artery and ICA in the anterior circulation and a Neuron
guiding catheter in the vertebral artery to the skull base to
treat the BA. The IA thromobolysis recanalizing technique is
described in a previous report [22]. Since October 2009, the
Penumbra System (Penumbra Inc, Alameda, CA, USA) has
been our standard reperfusion device. The PS was sized and
operated according to the manufacture’s recommendations
as described in a previous report [20]. From August 2010
onward, we have also used the solitaire FR thrombectomy
system (solitaire AB, solitaire FR; Microtherapeutics, ev3,
Irvine, CA) as a thrombectomy device in patients in whom
reopening of the target vessel could not be achieved by
the PS. The solitaire FR was used as described in a previous study [23]. Acute ICA occlusions were treated with
the Adapt carotid stent (Boston Scientific Corporation,
Natick, MA, USA) according to the manufacture’s
L. Fjetland et al.: Endovascular Acute Stroke Treatment
recommendations. All patients received an intra-arterial
dose of 5,000 IU heparin before the intervention. The femoral artery puncture site was sealed with 6F FemoSeal
(St. Jude Medical Inc, St. Paul, MN, USA) in all cases.
Efficacy and Safety Evaluation
Efficacy was assessed by the incidence of recanalization of
the target vessel. Angiographic recanalization was assessed
according to the thrombolysis in myocardial infarction
(TIMI) scoring system. Before treatment, patients were
required to have angiographic documentation of TIMI
score 0 or 1 flow in the target vessel at the site of primary
occlusion. Successful revascularization was defined by
angiographic demonstration of TIMI score 2 or 3 flow in
the target vessel [24, 25].
To assess safety, conventional brain magnetic resonance
(MR) imaging, including diffusion-weighted images,
apparent diffusion coefficient map, and MR cerebral
angiography or nonenhanced CT scan, was obtained within
24 h after completed intervention. This was performed to
determine the baseline extent of the infarcted area and to
detect and classify any hemorrhagic event. Additional CT
or MR imaging investigations were performed in case of
neurological deterioration. Safety of the treatment was
evaluated according to the incidence of procedural complications based on findings from procedure angiograms,
postprocedural MR/CT scans, and neurologic examinations. Vascular perforation, intramural arterial dissection,
embolization of previously uninvolved territories, and
groin complications were considered procedure-related
complications. Hemorrhagic events were classified
according to the European Cooperative Acute Stroke Study
II (ECASS II) classification of ICH [9]. Symptomatic ICH
(sICH) was defined by CT evidence of ICH associated with
a greater than four-point deterioration of the National
Institutes of Health Stroke Scale (NIHS) score [26].
1031
Table 1 Patient baseline characteristics and cardiovascular risk
factors (n = 39)
Mean age (SD) (year)
68.3 (14.2)
No. (%) female sex
10 (25.6)
Cardiovascular medical history (%)
Hypertension
27 (69.2)
Diabetes mellitus
6 (15.4)
Atrial fibrillation
11 (28.2)
Previous cardiovascular events
3 (7.7)
Previous cerebral events
5 (12.8)
were treated with IV thrombolysis before endovascular
recanalization. Clinical patient characteristics, including
their cardiovascular risk factors, are listed in Table 1.
Procedural technique, complications, and outcome are listed in Table 2.
Revascularization
All 39 patients had a baseline TIMI score of 0 or 1. We
used four different endovascular reperfusion techniques:
(1) 6 patients (15.4 %) were treated with IA thrombolysis;
(2) 20 patients (51.3 %) were treated with the PS; (3) 10
patients (25.6 %) were treated with the solitaire FR; and (4)
6 patients (15.4 %) were treated with an ICA stent, 4 of
them in combination with either the PS or the solitaire FR.
One patient was treated only with guidewire/catheter
manipulation. In 29 patients (74.4 %), we obtained a TIMI
score of 2 or 3 after treatment: 4 (67 %) in the IA thrombolysis group, 14 (70 %) in the PS group, and 9 (90 %) in
the solitaire group. Average time needed from symptom
onset to achieve TIMI score 2 or 3 revascularization was
5 h 11 min (SD 2.11).
Safety
Clinical Evaluation
Neurologic deficit was quantified using NIHSS and was
performed on admission, on the first day after intervention,
and at discharge. Modified Rankin scale (mRS) [27] score
was assessed at 3 month follow-up. Good neurologic outcome was defined as an mRS score B2 at day 90, and poor
neurologic outcome was defined as mRS score 3–6.
Results
During the study period, 914 patients were treated at the
hospital for ischemic stroke. Of these, 39 (4.3 %) were
treated with endovascular recanalization, and 28 (71.8 %)
Procedure-related complications occurred in two patients.
One patient developed a subarachnoid hemorrhage from
the posterior circulation during aspiration thrombectomy of
the MCA with the PS. The patient died the first postprocedural day. An iatrogenic carotid-cavernous fistula (CCF)
was observed in the other patient. This patient was closely
followed-up clinically and radiologically, and the CCF has
remained asymptomatic.
ICH was found at 24 h in 16 patients (40 %): Four
patients (10 %) had a haemorrhagic infarction (HI) 1, three
(7.5 %) had an HI 2, four (10 %) had a parenchymal
haemorrhage (PH) 1, and five (12.5 %) had a PH 2. Three
patients (7.5 %) had an sICH. Thus, the overall complication rate was 12.5 %.
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L. Fjetland et al.: Endovascular Acute Stroke Treatment
Table 2 Patient characteristics, procedural technique, complications, and outcome
Patient
Treatment
Periprocedural
complication
ICHa
mRS
scoreb
Age
(years)/sex
Occluded
artery
NIHSS
TIMI score
Pre
Before
After
1
70/F
MCA
15
0
0
IV rt-PA,d IA rtPAe
No
PH2
5
2
80/M
MCA
15
1
3
IV rt-PA, IA rtPA
No
PH2
0
3
79/M
MCA
25
1
3
IV rt-PA, IA rtPA
No
Non
3
4
88/M
MCA
19
0
3
IV rt-PA, IA rtPA
No
HI2
6
5
48/M
MCA
19
0
3
IV rt-PA, PS
No
Non
1
6
54/F
MCA
6
0
3
IV rt-PA, PS
No
Non
1
7
8
74/M
81/M
MCA
BA
16
26
0
0
0
3
IV rt-PA, IA rtPA
PS
No
No
PH2
Non
4
6
9
70/M
MCA
20
1
1
IV rt-PA, PS
No
Non
4
10
44/M
MCA
16
0
0
PS
No
Non
4
11
68/F
MCA
17
0
2
IV rt-PA, PS
No
Non
0
12
75/M
BA
19
0
3
IV rt-PA, PS
No
Non
0
13
66/M
MCA
13
0
1
IV rt-PA, PS
CCF
Non
4
14
87/F
MCA
20
0
1
IV rt-PA, PS
No
Non
6
15
34/M
BA
8
1
3
PS
No
Non
1
16
48/M
BA
15
0
3
IV rt-PA, PS
No
HI2
3
17
74/F
MCA
5
0
2
IV rt-PA, PS
No
HI1
0
18
67/F
MCA
22
0
3
IV rt-PA, solitaire
No
PH1
6
19
71/M
ICA
20
0
1
IV rt-PA, PS
No
Non
6
f
20
65/M
MCA/ICA
22
0
3
IV rt-PA, ICA stent /solitaire
No
PH1
4
21
85/M
MCA
18
0
1
solitaire
No
Non
4
22
23
56/M
56/F
MCA/ICA
MCA
19
20
0
0
3
2
IV rt-PA, ICA stent/PS
Solitaire
No
No
Non
HI1
1
4
24
79/F
MCA
*c
0
3
IV rt-PA, PS
Perforation
SAH
6
25
76/F
Carotid T
21
0
3
ICA stent/solitaire
No
PH2
4
26
81/M
MCA
19
0
2
IV rt-PA, solitaire
No
PH1
6
27
60/M
MCA
16
1
3
Guidewire
No
Non
2
28
44/M
BA
36
0
3
IV rt-PA, PS/IA rtPA
No
Non
3
29
84/F
MCA
25
0
3
IV rt-PA, solitaire
No
PH2
6
30
81/M
MCA
21
0
2
IV rt-PA, solitaire
No
HI1
6
31
49/M
MCA/ICA
20
1
3
IV rt-PA, IA rtPA
No
HI2
2
32
92/M
MCA
19
0
3
IV rt-PA, PS
No
Non
0
33
59/M
MCA
8
0
3
IV rt-PA, PS
No
HI1
0
34
66/M
MCA, ICA
17
0
0
PS
No
Non
4
35
70/M
MCA, ICA
13
0
0
ICA stent
No
Non
4
36
64/M
MCA, ICA
17
0
2
IV rt-PA, ICA stent/solitaire
No
Non
1
37
77/M
ICA
19
1
3
ICA stent
No
Non
4
38
39
55/M
84/M
BA
MCA
13
16
0
0
3
3
IV rt-PA, PS
Solitaire
No
No
Non
PH1
0
3
NIHSS National Institutes of Health Stroke Scale, TIMI thrombolysis in myocardial infarction
a
Intracerebral haemorrhage classified after ECASS I: HI1 haemorrhagic infarction 1, HI2 haemorrhagic infarction 2, PH1 parenchymal
haemorrhagic 1, PH2 parechymal haemorrhage 2
b
Modified rankin scale at 90 days
c
Intubated before arriving at the hospital
d
Intravenous thrombolysis
e
IA thrombolysis
Acute stenting of the ICA
f
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L. Fjetland et al.: Endovascular Acute Stroke Treatment
Mortality at 90 Days
Nine patients (22.5 %) died during the first 90 days after
the procedure. Six of these patients (66.7 %) were
[80 years of age. In the group of patients with postprocedure angiogram TIMI score of 0 or 1, two patients
(18.2 %) died: one from congestive heart failure and one
from a complete MCA infarction with consequent edema.
Among the patients with TIMI score of 2 or 3, seven
(24.1 %) died: three from cardiac causes (two from congestive heart failure and one from arrhythmia), two from
pulmonary causes (one each from pulmonary embolism
and aspiration), one from subarachnoid hemorrhage, and
one from anemia secondary to previously undiagnosed
rectal cancer. The difference in mortality between the
patient groups did not reach statistical significance.
Clinical Outcome
Fourteen patients (35.9 %) had a good clinical outcome
(mRS score B2) at day 90 after the procedure. Ten of these
patients were treated with the PS, 1 with the solitaire FR, 2
with IA thrombolysis, and 1 with guidewire/catheter
manipulation. Eight patients (32 %) with MCA occlusion,
3 (50 %) with basilar occlusion, and 3 (50 %) with tandem
lesions had a good clinical outcome. In the patients
[80 years, 2 patients (20 %) had a good clinical outcome.
At admission, the mean NIHSS score for all patients was
17.2 (SD 6.2 [n = 38]); after endovascular treatment the
mean NIHSS score decreased to 12.3 (SD 7.5 [n = 38]);
and by discharge the mean NIHSS score had decreased to
8.6 (SD 6.7 [n = 29]). The patients in whom treatment
failed (TIMI score 0 or 1) had a mean NIHSS score of 16.8
(SD 2.7 [n = 10]) at admission, which increased to 19.8
(SD 4.3) after treatment and decreased to 15.5 (SD 4.5
[n = 6]) before discharge. The patients who were successfully recanalized (TIMI score 2 or 3) had an initial
mean NIHSS score of 17.5 (SD 7.1 [n = 28]), which
decreased to 9.6 (SD 6.5) after treatment and further to 6.7
(SD 5.8 [n = 22]) before discharge. Mean mRS score for
all 39 patients was 3.2 (SD 2.2) at 90 days. For the 10
patients with TIMI score 0 or 1, mean mRS score was 4.5
(range 4–6). Four the 29 patients with TIMI score 2 or 3,
mean mRS score was 2.7 (range 0–6).
Discussion
In this study, we found that endovascular stroke treatment
performed by interventional radiologists, working in close
cooperation with diagnostic neuroradiologists and neurologists, appears to be a safe and feasible method of treating this
devastating disorder. Traditionally endovascular stroke
1033
treatment is performed by interventional neuroradiologists
alone, and it has been argued that it is difficult for general
interventional radiologists to obtain the expertise to make a
proper diagnosis and decide on the best treatment strategy
[28]. However, the delineated close cooperation of the previously mentioned specialists discussing the patient, as well
as the available treatment possibilities before, during, and
after treatment clearly, can compensate for this difficulty. In
addition, our team of general interventional radiologists has
been able to perform these complex procedures in a safe and
efficient manner. Thus, the presented approach of close
cooperation among different specialties may yield a model
by which to establish endovascular treatment possibilities in
hospitals without interventional neuroradiologists.
We achieved an average reopening rate of 74.4 %. This
is superior compared with the 66 % rate achieved in the
PROACT II Study [29] and the 56 % rate achieved in the
IMS study [22]. Yet the Penumbra Pivotal Stroke [20] and
the POST trials [30] reported reopening rates of 82 and
87 %, respectively. Moreover, case series using the solitaire FR have been published in which reopening rates
from 88 [31] to 100 % were achieved [16]. The corresponding figures in our study are within the range reported
in literature, which would seem to support our choice of
treatment strategy [13, 17].
The all over per-procedure complication rate in this study
was 5.1 %. Two adverse events were reported as we performed recanalization using the PS: In one patient, a perforation occurred resulting in fatal subarachnoidal
hemorrhage, and in another patient a CCF was diagnosed on
control scan after the intervention had been successfully
completed. Subarachnoidal hemorrhage caused by arterial
perforation has been reported in different studies using the
PS [15, 20, 30, 32] but also in studies using other mechanical
reperfusion techniques, such as the MERCI retriever [33] or
the solitaire FR [18, 21]. CCF has not been reported before
as complication of neurointerventional stroke treatment.
The periprocedural complication rate of 5.1 % achieved in
our patient sample is lower then the complication rates
reported in most other studies (5.8–12.8 %) [20, 30] and
shows that our team of vascular interventional radiologists
can perform this treatment safely.
Although we could detect intraparenchymal blood in 16
patients (41 %) on postprocedural CT/MRI scan, only 3
patients (7.5 %) showed sICH. An sICH rate of 7.5 % is in
the lower range of the published studies, i.e., 6.4 [30] to
12 % [22].
Nine patients died during the first 90 days after treatment (22.5 %). Interestingly, six of nine patients who died
were [80 years old, and only two patients died from
cerebrovascular causes (one from complete MCA infarction with edema and another from one subarachnoid
hemorrhage). In other studies using the PS (the system that
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1034
was used in the majority of our interventions), overall
mortality at 90 days varies between 11 and 45 % [15, 32].
Studies using the solitaire FR report a 90 day mortality rate
between 7.6 and 22.7 % [23, 34]. IA thrombolysis studies
report a 90 day mortality rate between 16 and 25 %
[22, 29]. However, it may be pertinent to point out that in
most of these studies [15, 32, 34], patients [80 years old
were not included. If this group of patients is excluded, the
90 day mortality rate in our series is 10.3 %, which is in
the lower end of the range in published studies.
Altogether, 14 patients had an mRS score of B2 after
90 days (35.9 %). The patients \80 years of age in our
study had a good clinical outcome in 41.4 % of cases.
Good clinical outcomes in the literature vary between 35
and 40 % in studies using IAT [29, 35], between 15 and
48 % [32, 35] using the PS, and between 38 and 88.2 %
[16, 34] using the solitaire FR.
Our clinical results are in line with those in the published
literature, and our 90 day mortality rate is in the lower end
of the range; together they confirm the quality of our
treatment strategy. In line with our approach, some stroke
centres have chosen to integrate the general interventional
radiologist into their interventional team and employ either
a mixed team of interventional neuroradiologists and general interventional radiologists or a team staffed completely
by general interventional radiologists. A report from one of
these centres shows excellent results [36].
The relatively low number of patients treated limits
somewhat the validity of the conclusions that can be drawn
from the results. Nonetheless, our experience supports the
movement toward expanding the geographical availability
of endovascular treatment for acute stroke by unlocking the
synergy inherent in close cooperation between stroke
neurologists, diagnostic neuroradiologists, and vascular
interventional radiologists. By adopting this approach, we
successfully established a full-fledged stroke treatment
facility in a centre without interventional neuroradiologists.
It is hoped that our experience will encourage other hospitals in a similar predicament to explore a similar pathway
to supplement their therapeutic armamentarium for the
treatment of acute stroke.
Conflict of interest Jan Petter Larsen reports board membership for
Lundbeck Pharma and receiving payment for lectures from Lundbeck
Pharma. Martin W. Kurz reports receiving payment for lectures from
Boehringer Ingelheim and Pfizer.
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