Downloaded from http://jnis.bmj.com/ on July 21, 2015 - Published by group.bmj.com
Ischemic stroke
ORIGINAL RESEARCH
Impact of the ASPECT scores and distribution on outcome among patients undergoing thrombectomy for acute ischemic stroke Alejandro M Spiotta,1 Jan Vargas,1 Harris Hawk,2 Raymond Turner,1 M Imran Chaudry,2 Holly Battenhouse,3 Aquilla S Turk2 1
Division of Neurosurgery, Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina, USA 2 Department of Radiology, Neurointerventional, Medical University of South Carolina, Charleston, South Carolina, USA 3 Data Coordination Unit, Department of Public Health Services, Medical University of South Carolina, Charleston, South Carolina, USA Correspondence to Dr Alejandro M Spiotta, Division of Neurosurgery, Department of Neurosciences, Medical University of South Carolina, Charleston, SC 29425, USA; [email protected] Received 5 March 2014 Revised 16 May 2014 Accepted 19 May 2014 Published Online First 10 June 2014
ABSTRACT Introduction This study investigates whether the Alberta Stroke Program Early CT Score (ASPECTS) quantification is associated with outcome following mechanical thrombectomy. Objective To determine whether preintervention non-perfect ASPECT scores involving cortical or subcortical regions and the side of the non-perfect ASPECT score affects outcomes. Methods A retrospective review of a prospectively maintained database of patients with acute ischemic stroke involving the anterior circulation who underwent thrombectomy between May 2008 and August 2012 at a single tertiary care center. The device for mechanical thrombectomy used was the penumbra aspiration system (Penumbra Inc, Alameda, California, USA) and the Solitaire stent retriever (ev3, Irvine, California, USA). A ‘blinded’ neuroradiologist obtained ASPECTS quantification and noted each region demonstrating early changes. Results 149 patients (51.7% female, mean age 66.1 ±15.1 years) were included with an average National Institutes of Health Stroke Scale of 16.2±6.7. Patients with non-perfect ASPECT scores on pretreatment imaging were more likely to have a hemorrhagic conversion ( p=0.04) evident on post-procedure CT. However, functional outcomes were the same. Patients with both cortical and basal ganglia non-perfect ASPECT scores were more likely to be in a persistent vegetative state or expire. No differences were identified in outcome among patients with left- versus right-sided infarcts affecting the basal ganglia or cortical regions. Conclusions These findings support a strategy of selecting candidacy for thrombectomy that does not exclude patients with non-perfect ASPECT scores involving either the basal ganglia or cortical regions. Outcomes were identical among patients with no non-perfect ASPECT scores and those with cortical or subcortical infarcts, despite a higher incidence of hemorrhagic conversion found among those with non-perfect ASPECT scores.
INTRODUCTION
To cite: Spiotta AM, Vargas J, Hawk H, et al. J NeuroIntervent Surg 2015;7:551–558.
While the intravenous administration of thrombolytic agents (intravenous tissue plasminogen activator (IV tPA)) is the ‘gold standard’ for treatment of acute ischemic stroke (AIS),1 mechanical thrombectomy remains an option for those who are evaluated when treatment is not possible or otherwise
do not qualify for IV tPA.2–5 Recent studies have shown clinical benefit for patients when mechanical recanalization can be achieved,6–11 underlining the importance of patient selection for intra-arterial therapy with imaging.4 Although fraught with inter-rater variability, the Alberta Stroke Program Early CT Score (ASPECTS) is a widely accepted scoring system that may help in the triaging of patients with AIS.12–16 ASPECTS has been shown to correlate with the National Institutes of Health Stroke Scale (NIHSS) on presentation and the likelihood of intracerebral hemorrhage and outcome after IV tPA administration.17 ASPECTS may be used in the evaluation of patients undergoing thrombectomy for AIS, but its predictive value remains to be proved. We investigated whether ASPECTS quantification with non-contrast and perfusion CT is associated with hemorrhagic conversion and outcome after mechanical thrombectomy. In addition, we examine whether infarct patterns on initial CT involving cortical or subcortical regions and the side of a non-perfect ASPECT score affects outcomes.
METHODS We retrospectively studied a prospectively maintained database of consecutive patients with AIS who underwent intra-arterial therapy between May 2008 and August 2012 at a high-volume tertiary care center (Medical University of South Carolina). The study was approved by the institutional review board of the Medical University of South Carolina. Mechanical thrombectomy was the preferred treatment for AIS. Candidacy for intervention was determined by CT perfusion imaging, irrespective of time of onset.5 Our protocol for determining candidacy does not employ strict ASPECTS criteria or thresholds. Rather, clinical judgment is employed and the treating interventionalist determines if recanalization in the presence of a non-perfect ASPECT score would improve the patient’s eventual outcome. In general, patients with non-perfect ASPECT scores but with regions of penumbra thought to contribute significantly to the NIHSS were eligible for recanalization. This study aimed at investigating whether this approach was effective in identifying those patients most likely to benefit from recanalization. Patients who received IV tPA were also candidates for mechanical thrombectomy. During the study, the
Spiotta AM, et al. J NeuroIntervent Surg 2015;7:551–558. doi:10.1136/neurintsurg-2014-011195
551
Downloaded from http://jnis.bmj.com/ on July 21, 2015 - Published by group.bmj.com
Ischemic stroke Table 1
All subjects with anterior circulation by ASPECT score status (perfect vs non-perfect) Perfect (ASPECTS 10) (N=49)
N (N=149) mRS (90 days) 0 1 2 3 4 5 6 Traditional dichotomy (90 days) mRS 0–-2 mRS 3–6 Alternative dichotomy (90 days) mRS 5–6 mRS 0–4 Death (mRS=6 at 90 days) Yes No Hemorrhage Yes No Symptom onset to procedure time (h), mean (SD) Recanalization time (min), mean (SD) Age (years), mean (SD) Post TICI flow TICI 0–2A TICI 2B–3 Gender (female) Type (not perfect only) Subcortical Cortical Subcortical and Cortical Side Left Right Procedural complications Yes No Clinically significant event Yes No Hyperdense MCA Yes No
Not perfect (ASPECTS ≤9) (N=100)
137
p Value* 0.6719
7 (15.6) 10 (22.2) 4 (8.9) 8 (17.8) 8 (17.8) 1 (2.2) 7 (15.6)
11 (12.0) 14 (15.2) 14 (15.2) 14 (15.2) 15 (16.3) 8 (8.7) 16 (17.4)
21 (46.7) 24 (53.3)
39 (42.4) 53 (57.6)
8 (17.8) 37 (82.2)
24 (26.1) 68 (73.9)
7 (15.6) 38 (84.4)
16 (17.4) 76 (82.6)
4 (8.2) 45 (91.8) 9.7 (6.8) 82.2 (43.6) 66.0 (15.4)
23 (23.0) 77 (77.0) 9.1 (9.1) 77.4 (41.2) 67.2 (15.2)
7 (15.2) 39 (84.8) 26 (53.1)
25 (25.3) 74 (74.7) 59 (59.0)
137
0.6357
137
0.2803
137
0.7872
149
0.0399
144 144 149 145
149 100
0.6816 0.5269 0.6445 0.1751
0.4915
29 (29.0) 35 (35.0) 36 (36.0) 146
0.3394 29 (60.4) 19 (39.6)
51 (52.0) 47 (48.0)
4 (8.2) 45 (91.8)
7 (7.0) 93 (93.0)
1 (2.0) 48 (98.0)
6 (6.0) 94 (94.0)
12 (24.5) 37 (75.5)
67 (67.0) 33 (33.0)
149
0.7514
149
0.4266
149
Ischemic stroke
ORIGINAL RESEARCH
Impact of the ASPECT scores and distribution on outcome among patients undergoing thrombectomy for acute ischemic stroke Alejandro M Spiotta,1 Jan Vargas,1 Harris Hawk,2 Raymond Turner,1 M Imran Chaudry,2 Holly Battenhouse,3 Aquilla S Turk2 1
Division of Neurosurgery, Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina, USA 2 Department of Radiology, Neurointerventional, Medical University of South Carolina, Charleston, South Carolina, USA 3 Data Coordination Unit, Department of Public Health Services, Medical University of South Carolina, Charleston, South Carolina, USA Correspondence to Dr Alejandro M Spiotta, Division of Neurosurgery, Department of Neurosciences, Medical University of South Carolina, Charleston, SC 29425, USA; [email protected] Received 5 March 2014 Revised 16 May 2014 Accepted 19 May 2014 Published Online First 10 June 2014
ABSTRACT Introduction This study investigates whether the Alberta Stroke Program Early CT Score (ASPECTS) quantification is associated with outcome following mechanical thrombectomy. Objective To determine whether preintervention non-perfect ASPECT scores involving cortical or subcortical regions and the side of the non-perfect ASPECT score affects outcomes. Methods A retrospective review of a prospectively maintained database of patients with acute ischemic stroke involving the anterior circulation who underwent thrombectomy between May 2008 and August 2012 at a single tertiary care center. The device for mechanical thrombectomy used was the penumbra aspiration system (Penumbra Inc, Alameda, California, USA) and the Solitaire stent retriever (ev3, Irvine, California, USA). A ‘blinded’ neuroradiologist obtained ASPECTS quantification and noted each region demonstrating early changes. Results 149 patients (51.7% female, mean age 66.1 ±15.1 years) were included with an average National Institutes of Health Stroke Scale of 16.2±6.7. Patients with non-perfect ASPECT scores on pretreatment imaging were more likely to have a hemorrhagic conversion ( p=0.04) evident on post-procedure CT. However, functional outcomes were the same. Patients with both cortical and basal ganglia non-perfect ASPECT scores were more likely to be in a persistent vegetative state or expire. No differences were identified in outcome among patients with left- versus right-sided infarcts affecting the basal ganglia or cortical regions. Conclusions These findings support a strategy of selecting candidacy for thrombectomy that does not exclude patients with non-perfect ASPECT scores involving either the basal ganglia or cortical regions. Outcomes were identical among patients with no non-perfect ASPECT scores and those with cortical or subcortical infarcts, despite a higher incidence of hemorrhagic conversion found among those with non-perfect ASPECT scores.
INTRODUCTION
To cite: Spiotta AM, Vargas J, Hawk H, et al. J NeuroIntervent Surg 2015;7:551–558.
While the intravenous administration of thrombolytic agents (intravenous tissue plasminogen activator (IV tPA)) is the ‘gold standard’ for treatment of acute ischemic stroke (AIS),1 mechanical thrombectomy remains an option for those who are evaluated when treatment is not possible or otherwise
do not qualify for IV tPA.2–5 Recent studies have shown clinical benefit for patients when mechanical recanalization can be achieved,6–11 underlining the importance of patient selection for intra-arterial therapy with imaging.4 Although fraught with inter-rater variability, the Alberta Stroke Program Early CT Score (ASPECTS) is a widely accepted scoring system that may help in the triaging of patients with AIS.12–16 ASPECTS has been shown to correlate with the National Institutes of Health Stroke Scale (NIHSS) on presentation and the likelihood of intracerebral hemorrhage and outcome after IV tPA administration.17 ASPECTS may be used in the evaluation of patients undergoing thrombectomy for AIS, but its predictive value remains to be proved. We investigated whether ASPECTS quantification with non-contrast and perfusion CT is associated with hemorrhagic conversion and outcome after mechanical thrombectomy. In addition, we examine whether infarct patterns on initial CT involving cortical or subcortical regions and the side of a non-perfect ASPECT score affects outcomes.
METHODS We retrospectively studied a prospectively maintained database of consecutive patients with AIS who underwent intra-arterial therapy between May 2008 and August 2012 at a high-volume tertiary care center (Medical University of South Carolina). The study was approved by the institutional review board of the Medical University of South Carolina. Mechanical thrombectomy was the preferred treatment for AIS. Candidacy for intervention was determined by CT perfusion imaging, irrespective of time of onset.5 Our protocol for determining candidacy does not employ strict ASPECTS criteria or thresholds. Rather, clinical judgment is employed and the treating interventionalist determines if recanalization in the presence of a non-perfect ASPECT score would improve the patient’s eventual outcome. In general, patients with non-perfect ASPECT scores but with regions of penumbra thought to contribute significantly to the NIHSS were eligible for recanalization. This study aimed at investigating whether this approach was effective in identifying those patients most likely to benefit from recanalization. Patients who received IV tPA were also candidates for mechanical thrombectomy. During the study, the
Spiotta AM, et al. J NeuroIntervent Surg 2015;7:551–558. doi:10.1136/neurintsurg-2014-011195
551
Downloaded from http://jnis.bmj.com/ on July 21, 2015 - Published by group.bmj.com
Ischemic stroke Table 1
All subjects with anterior circulation by ASPECT score status (perfect vs non-perfect) Perfect (ASPECTS 10) (N=49)
N (N=149) mRS (90 days) 0 1 2 3 4 5 6 Traditional dichotomy (90 days) mRS 0–-2 mRS 3–6 Alternative dichotomy (90 days) mRS 5–6 mRS 0–4 Death (mRS=6 at 90 days) Yes No Hemorrhage Yes No Symptom onset to procedure time (h), mean (SD) Recanalization time (min), mean (SD) Age (years), mean (SD) Post TICI flow TICI 0–2A TICI 2B–3 Gender (female) Type (not perfect only) Subcortical Cortical Subcortical and Cortical Side Left Right Procedural complications Yes No Clinically significant event Yes No Hyperdense MCA Yes No
Not perfect (ASPECTS ≤9) (N=100)
137
p Value* 0.6719
7 (15.6) 10 (22.2) 4 (8.9) 8 (17.8) 8 (17.8) 1 (2.2) 7 (15.6)
11 (12.0) 14 (15.2) 14 (15.2) 14 (15.2) 15 (16.3) 8 (8.7) 16 (17.4)
21 (46.7) 24 (53.3)
39 (42.4) 53 (57.6)
8 (17.8) 37 (82.2)
24 (26.1) 68 (73.9)
7 (15.6) 38 (84.4)
16 (17.4) 76 (82.6)
4 (8.2) 45 (91.8) 9.7 (6.8) 82.2 (43.6) 66.0 (15.4)
23 (23.0) 77 (77.0) 9.1 (9.1) 77.4 (41.2) 67.2 (15.2)
7 (15.2) 39 (84.8) 26 (53.1)
25 (25.3) 74 (74.7) 59 (59.0)
137
0.6357
137
0.2803
137
0.7872
149
0.0399
144 144 149 145
149 100
0.6816 0.5269 0.6445 0.1751
0.4915
29 (29.0) 35 (35.0) 36 (36.0) 146
0.3394 29 (60.4) 19 (39.6)
51 (52.0) 47 (48.0)
4 (8.2) 45 (91.8)
7 (7.0) 93 (93.0)
1 (2.0) 48 (98.0)
6 (6.0) 94 (94.0)
12 (24.5) 37 (75.5)
67 (67.0) 33 (33.0)
149
0.7514
149
0.4266
149
