Abstract
Background and purpose
A direct aspiration first pass technique involves first-line aspiration to remove the thrombus through a large-bore aspiration catheter in large vessel strokes. The aim of this study was to assess safety and clinical outcomes with a direct aspiration first pass technique using the new ARC catheter.
Methods
A retrospective analysis of prospectively collected data from three university hospitals was performed between June 2016 and May 2018. The following parameters of all acute ischemic stroke interventions using the ARC catheter were analyzed: use of intravenous thrombolysis, National Institutes of Health Stroke Scale scores at presentation and discharge, successful reperfusion (modified Thrombolysis in Cerebral Infarction 2b–3), procedure duration, procedure-related complications and 90-day clinical outcome (modified Rankin Scale score).
Results
In total, 41 patients were included in the study and anterior circulation occlusion was noted in 35 (85%). The median National Institutes of Health Stroke Scale at admission was 18 and prior intravenous thrombolysis was administered in 35 patients (85%). Only six (15%) patients required the use of a rescue stent retriever. Successful reperfusion was achieved in 40 patients (98%) with a median procedure time of 32 minutes. No catheter-related complications were observed. Symptomatic intracerebral hemorrhage occurred in one patient (2%). Median National Institutes of Health Stroke Scale at discharge was 3; 49% were independent and 10% died at 90 days.
Conclusions
In the present study, the ARC catheter allowed a 98% successful reperfusion rate. The complication rate was in line with those of previous a direct aspiration first pass technique publications.
Keywords: ADAPT, catheter, stroke, thrombectomy
Introduction
Mechanical thrombectomy has become the standard treatment in patients with acute ischemic stroke caused by occlusion of the arteries of the proximal anterior circulation.1 In these therapeutic trials, most patients were treated by a stent retriever technique.1,2 However, several new endovascular methods have been developed for thrombectomy in acute ischemic stroke. One of these new techniques is a direct aspiration first pass technique (ADAPT). ADAPT requires the use of large-bore catheter involving a first-line aspiration to remove the thrombus through a large-bore aspiration catheter.3 ADAPT reperfusion rates appear similar to other techniques and, in case of failure, the use of large bore catheter allows the operator to quickly switch to a retriever stent technique.4 Initially produced by Penumbra,5 several companies have developed their own large-bore aspiration catheters. Safety and efficacy of the new ARC catheter (Medtronic, Irvine, California, USA) have been previously assessed in a small monocentric study.6
The purpose of the present study was to extend the preliminary results with the ARC aspiration catheter in terms of reperfusion efficacy, duration of thrombectomy, safety of the procedure and clinical outcomes through a multicenter study.
Patients and methods
Patient selection
All patients with acute ischemic stroke due to large vessel occlusion treated with mechanical thrombectomy using an ARC catheter were retrospectively identified in three university centers between June 2016 and May 2018. Prospectively collected data were extracted from an endovascular database. The use of the ARC catheter for stroke intervention was left at the discretion of the interventionist. Approval of the local ethics committee of the participating centers was obtained.
The ARC catheter
ARC catheters are designed specifically for intracranial thrombectomy, allowing their use either for ADAPT or for combined techniques (combined ADAPT and stent retriever). The Food and Drug Administration has approved the ARC for neurovascular access during diagnostic or therapeutic interventions. The ARC 6F support catheter is a flexible, single-lumen, variable-stiffness composite catheter with a usable length of 132 cm, a distal inner diameter of 0.061 inches and a distal outer diameter of 0.069 inches. The ARC catheter has a straight tip configuration and a band-like radiopaque platinum marker at its distal tip, allowing proper visualization under fluoroscopic guidance. Owing to a proximal outer diameter of 0.080 inches, the ARC 6F cannot be used with most available 8F catheters and requires the use of a 9F guide catheter. The ARC-mini is a 160 cm 3F intermediate catheter with a 0.035 inch distal inner diameter and a 0.044 inch distal outer diameter. ARC and ARC-mini catheters are tapered in design.
Endovascular intervention
The interventional procedures were performed under general anesthesia or consciousness according to the local setting. Via transfemoral sheath, a 9F guide catheter (Cello; Medtronic, Irvine, California, USA, or Merci; Stryker, Fremont, California, USA) was placed in the internal carotid artery or vertebral artery according to the site of occlusion. Subsequently, the ARC was advanced either over an intermediate catheter (ARC-mini catheter) or a Marksman microcatheter (Medtronic, Irvine, California, USA) with a standard 0.014 inch micro-guidewire (Transend 14; Stryker, Fremont, California, USA, or Traxcess; Microvention Terumo, Tustin, California, USA). Finally, in selected cases the ARC could be advanced by itself over a 0.035 guidewire. Once in the occluded vessel, the ARC catheter was then advanced in contact with the thrombus. After coaxial guiding device removal, aspiration was carried out using a 60 cc syringe locked to the ARC. The resulting vacuum was maintained for at least 90 seconds before slow retraction of the ARC started. If a backflow inside the ARC was observed, the catheter was left in place and checked for free aspiration to rule out a remaining clot before injecting the contrast to control for revascularization success. If the vacuum remained during catheter withdrawal, the ARC was removed completely from the patient. If unsuccessful, this maneuver was repeated up to three times before considering a failure of the ADAPT approach. A rescue stent retriever (Solitaire2; Medtronic, Irvine, California, USA, or Trevo; Stryker, Fremont, California, USA) was used in case of failure of this first-line aspiration approach, defined as modified Thrombolysis in Cerebral Ischemia (mTICI) scores 0–2a, or failure of the ARC navigation to reach the occlusion. The stent retriever was used together with aspiration through the ARC catheter whereas the stent retriever was removed concomitantly to the ARC catheter withdrawal. Each of these mechanical thrombectomy maneuvers were performed under protection of the inflated catheter balloon through which a vacuum was applied using a using a 60 cc Luer Lock syringe. No heparin or nimodipine was administered during the procedure.
Angiographic and clinical outcomes
For each patient, the following data were collected:
Baseline characteristics: sex, age, National Institutes of Health Stroke Scale (NIHSS), location of the thrombus, Alberta Stroke Program Early CT Score (ASPECTS), prior intravenous (IV) thrombolysis, and delay between symptom onset and IV thrombolysis.
Procedure-related variables: delay between symptom onset and groin puncture, type of anesthesia, initial mTICI, thrombectomy technique, number of passes, final mTICI, delay between puncture-final mTICI, delay from onset of symptoms to final mTICI, procedural complications. The initial and final mTICI scores7 were assessed by the treating physician, and successful reperfusion was defined as mTICI 2b–3.
Follow-up: NIHSS at 24 hours and at discharge, stroke etiology, and clinical outcome using the modified Rankin Scale (mRS) score at 90 days. Stroke etiology was defined according to the Trial of Org 10172 in Acute Stroke Treatment classification. Clinical outcome was assessed at 90 days during face-to-face interviews or via telephone calls by trained research nurses. Intracranial hemorrhage complication was evaluated on brain imaging at 24 hours, intracranial hemorrhage was graded according to the European Co-operative Acute Stroke Study-II criteria)8 and symptomatic hemorrhage was defined as any hemorrhage on follow-up imaging associated with an increase of ≥4 points in the NIHSS score.
Results
Patients
In a total of 921 thrombectomies for large vessel occlusion during the inclusion period, 41 patients were treated with ADAPT using the ARC (4/343 and 15/321 in the two French centers and 22/257 in the English center). Of these patients 18 were female and 23 male with a mean age of 66 ± 14 years (Table 1). Median NIHSS score at baseline was 18 (range: 0–42). The site of vessel occlusion was the anterior circulation for 35 patients (85%), including four terminal internal carotid artery occlusions, 21 M1 segment occlusions, two M2 segment occlusions, and eight intra-extracranial tandem occlusions. The median ASPECTS was 8 (range: 4–10). IV thrombolysis prior to thrombectomy was administered in 35 patients (85%), with a median time from symptoms onset to thrombolysis of 148 minutes (range: 65–310 min).
Table 1.
Demographics and baseline clinical and imaging characteristics.
| Number of patients | 41 |
|---|---|
| Age (years) mean ± SD | 66 ± 14 |
| Female (%) | 18 (44) |
| Initial NIHSS median (range) | 18 (0–42) |
| Intravenous thrombolysis (%) | 35 (85) |
| Time from symptom onset to Intravenous thrombolysis (min), median (range) | 148 (65–310) |
| Site of arterial occlusion (%) | |
| Tandem | 8 (20) |
| Terminal internal carotid artery | 4 (10) |
| M1 middle cerebral artery | 21 (51) |
| M2 middle cerebral artery | 2 (5) |
| Posterior circulation | 6 (14) |
| ASPECTS median (range) | 8 (4–10) |
| TOAST (%) | |
| Cardioembolic | 20 (49) |
| Large artery atherosclerosis | 18 (44) |
| Undetermined | 3 (7) |
| Number of passes median (range) | 2 (1–5) |
| Final mTICI (%) | |
| <2b | 1 (2) |
| 2b–3 | 40 (98) |
| Time from puncture to mTICI 2b–3 (min), median (range) | 30 (7–65) |
| Time from onset to mTICI 2b–3 (min), median (range) | 255 (117–420) |
| NIHSS at 24 hours median (range) | 7 (0–42) |
| NIHSS at discharge median (range) | 3 (0–25) |
| mRS at 90 days | |
| 0–2 | 19/39 |
| 2–5 | 24/39 |
| 6 | 4/39 (10%) |
ASPECTS: Alberta Stroke Program Early CT Score; mTICI: modified Thrombolysis in Cerebral Ischemia; mRS, modified Rankin Scale; NIHSS: National Institutes of Health Stroke Scale; TOAST: Trial of Org 10172 in Acute Stroke Treatment.
Angiographic results
The median delay between symptom onset and groin puncture was 220 minutes (range: 83–380 min). Thrombectomy procedure was performed under general anesthesia in 21 cases (51%). Initial mTICI was 0 in 35 cases (85%), 1 in one case (2%), 2a in four cases (10%), and 2b in one case (2%).
The ADAPT approach (Figure 1) failed in six patients. For these six patients (15%) the use of a rescue stent retriever (three Solitaire 6x30 mm and three Solitaire 4x30 mm) was needed due to the failure of ARC intracranial navigation. A combined technique (Figure 2) was used in five of these patients. In the last case (an M2 occlusion) the ADAPT could not reach the clot. The median total number of passes was two (range: 1–5) with 20 (41%) successful procedures after only one pass. At the end of the procedure, final mTICI was 2a in one case (2%), 2b in 12 cases (29%), 2c in three cases (7%) and 3 in 25 cases (61%). The median symptom onset to final mTICI was 255 minutes (range: 11−420 min). Procedural complications occurred in eight patients (20%) including two embolic new territory complications (5%), four intra cranial artery spasms (10%), and two arterial dissections (5%). There was one case of vessel perforation secondary to an attempt of thrombectomy in a new embolic territory (proximal segment of the pericallosal artery).
Figure 1.
ADAPT with ARC catheter. (a) and (b) Pretreatment anterior and lateral angiograms demonstrate a major tortuosity of the extracranial internal carotid artery. (c) and (d) Pretreatment angiogram shows distal M1 segment of middle cerebral artery occlusion (white arrow). (e) and (f) Pretreatment images: the ARC is advanced in face of the clot (white arrow). After that an aspiration force is exerted and the ARC is slowly removed. (g) and (h) Anterior and lateral angiograms show a successful reperfusion after only one pass.
Figure 2.
Combined technique with ARC and Solitaire Platinum 6 x 40. (a) and (b) Pretreatment anterior and lateral angiograms demonstrate a standard anatomy of the extracranial internal carotid artery. (c) and (d) Pretreatment angiogram shows distal intern carotid occlusion (white arrow). (e) and (f) Pretreatment images: the ARC (white arrow) is advanced as far as possible over a mini catheter. Anterior and lateral native images show the placement of the Solitaire 4 x 20 mm (black arrow) in the middle cerebral artery. After that, ARC aspiration is used in association with Solitaire thrombectomy. (g) and (h) Anterior and lateral angiograms show a successful reperfusion.
Clinical outcomes
Four patients (10%) showed intracranial hemorrhage complications on their follow-up computed tomography (CT) performed within 24 hours (three parenchymal hematoma type I and one parenchymal hematoma type II) with an overall rate symptomatic intracranial hemorrhage of 2%. The stroke etiology was large artery atherosclerosis for 18 patients (44%), and cardio-embolic for 20 patients (49%). For the three last patients (7%) etiological explorations remained unsettled. Mean NIHSS at 24 hours and at discharge were 10 (median: 7, range: 0–42) and 5 (median: 3, range: 0–25) respectively. The median mRS score at 90 days was 2, and four patients (4/39; 10%) died within 90 days.
Discussion
ADAPT is an increasingly used technique in endovascular stroke intervention worldwide. In retrospective comparative studies, ADAPT offers a similar or better recanalization rate compared to the standard stent retriever technique.9,10 Moreover, the use of this technique remains relevant since the recent reported results in the ASTER11 and COMPASS trials.12,13 Its main principle relies on vacuum and suction force to remove the intracranial clot. In this technique, the probe needs to be placed in front of the clot, then aspiration is applied. The catheter is then slowly withdrawn while aspiration is maintained. In this ideal case, the catheter tip is occluded by the clot and the exerted aspiration force depends only on the size of the catheter tip and the vacuum pressure.14 Hence, a good aspiration catheter for thrombectomy requires two main features: an easy intracranial navigation and a wide distal bore. With the 5 MAX ACE, Penumbra was the first company offering such a catheter;5 since then several companies have developed their own large-bore catheters. The main specifications of these large-bore aspiration catheters and their distal vacuum pressures are summarized in Table 2.
Table 2.
Characteristics of main new generation large-bore catheters.
| Working length (A) | Proximal outer diameter (B) | Distal outer diameter (C) | Proximal inner diameter (D) | Distal inner diameter (E) | Mean vacuum pressure with a 60 mL locking syringe (in inches Hg)14 | |
|---|---|---|---|---|---|---|
| ARC | 132 cm | 0.080”/6.1F | 0.069”/5.3F | 0.069”/5.3F | 0.061”/4.7F | 27.17 |
| AXS Catalyst 6 | 132 cm | 0.079”/6.0F | 0.071”/5.4F | 0.060”/4.6F | 0.060”/4.6F | 27.50 |
| SOFIA Plus | 125 or 131 cm | 0.0825”/6.3F | 0.0815”/6.2F | 0.070”/5.3F | 0.070”/5.3F | N/A |
| ACE 64 | 132 cm | 0.080”/6.0F | 0.076”/5.75F | 0.068”/5.2F | 0.064”/4.9F | 26.67 |
| ACE 68 | 132 cm | 0.080”/6.0F | 0.080”/6.0F | 0.068”/5.2F | 0.068”/5.2F | N/A |
The present study reinforces the results of a previous study,6 by including more patients and multicenter data. In the previous study including 20 large vessel occlusion stroke patients, an overall mTICI 2b–3 rate was achieved in 80% of cases within a median time of 31 minutes. There were no device-related events, 35% were independent and 35% of patients died at 90 days. In a recent published meta-analysis (including mainly 5 MAX, 5 MAX ACE and ACE 64 catheters),4 the TICI 2b–3 rate was 66% (95% confidence interval (CI), 59–72%) with ADAPT. A rescue stent retriever was used in 31% of cases (95% CI, 24–37%), yielding an overall TICI 2b–3 rate of 89% (95% CI, 85–92%). Gory et al. found a pooled estimate of 50% (95% CI, 45–54%) for functional independence (90 day mRS 0–2), and 15% (95% CI, 10–21%) for mortality within 90 days. The present results confirm that intracranial thrombectomy with the ARC catheter is safe and effective. In fact, successful reperfusion was achieved in 98%, and 49% of patients were independent (mRS 0–2) at 90 days. These results were compared with those of other large bore catheters and with stent retriever devices (Table 3). For example, in the multicenter study with the Sofia Plus catheter including 85 patients,15 the overall TICI 2b–3 rate was 96.5% within a duration procedure of 21 minutes. At 90 days, mRS 0–2 was achieved in 49.4% of cases and the mortality rate was 20%.
Table 3.
Safety and clinical outcomes of main in comparison with other contact aspiration or stent-retriever thrombectomy studies.
| ARC (n = 41) | SOFIA Plus (n = 85)15 | ACE (n = 1113)4 | Catalyst (n = 107)19 | Solitaire (n = 401)2 | Stent Retriever (n = 634)2 | TREVO (n = 634)20 | |
|---|---|---|---|---|---|---|---|
| Median NIHSS at baseline | 18 | 18 | 17 | 17 | 17 | 17 | 17* |
| Median NIHSS at 24 hours | 7 | – | – | – | – | 8 | – |
| Median NIHSS at discharge | 3 | 4.5 | – | – | – | – | 17* |
| Previous IV tPA | 35/41 (85) | 51 (60) | 576 (52) | 67 (62.6) | 323 (80) | 526 (83) | 321 (51) |
| mTICI 2b–3 | 40/41 (98) | 82 (96) | 967 (89) | 90 (84.1) | 285 (76) | 402 (71) | 505 (80) |
| mTICI 3 | 25/41 (61) | 53 (62) | 247 (53) | 68 (63.5) | 132 (35) | – | 280 (45) |
| Use of a rescue stent retriever | 6/41 (15) | 30 (35) | 356 (30) | 25 (23.4) | – | – | – |
| Mean time from puncture to mTICI 2b–3, minutes | 32 | – | 46 | 40 | 38 | – | 67* |
| Mean time from onset to mTICI 2b–3, minutes | 261 | – | 277 | 272 | 274 | 285 | 363 |
| ENT | 2/41 (5) | 4 (5) | 32 (2) | – | – | – | – |
| sICH | 1/41 (2) | 4 (5) | 40 (4) | 4 (3.7) | 10 (2) | 28 (4) | 44 (7) |
| 90 day mRS 0–1 | 14/39 (36) | 27 (32) | – | – | 143 (36) | 170 (27) | – |
| 90 day mRS 0–2 | 19/39 (49) | 42 (49) | 474 (51) | 51 (47.6) | 216 (54) | 291 (46) | 277 (47.9) |
| 90 day all-cause mortality | 4/39 (10%) | 17 (20) | 128 (13) | 23 (21.4) | 48 (15) | 97 (15) | 106 (20) |
Values expressed as number/total number (%) or number unless otherwise as indicated.
NIHSS, National Institutes of Health Stroke Scale; IV tPA, intravenous tissue plasminogen activator; mTICI, modified Thrombolysis in Cerebral Ischemia; ENT, embolic new territory; sICH, symptomatic intracranial hemorrhage; mRS, modified Rankin Scale.
sICH was defined as any parenchymal hematoma, subarachnoid hemorrhage, or intraventricular hemorrhage associated with worsening of the NIHSS score by ≤4 within 24 hours.
Mean value (median value unknown).
The use of a rescue stent retriever was relatively rare (15%) in our study. This can be explained by protocol variations (fewer direct aspiration attempts can be tolerated depending on the operator). The percentage of patients with 90 day mRS 0-2 (49%) in our study is similar to other reports and our mortality rate is slightly lower. However, the comparison between our results and those of other studies is altered by differences in clinical and imaging characteristics at baseline, which may impact reperfusion and clinical outcome.16 Safety parameters were comparable with other catheters. Similar to the previously reported study,6 there were no device-related events in our enlarged cohort. The cases of vessel dissection and the case of vessel perforation were related to guide or micro-guide maneuvers and not to the catheter.
We are aware of several limitations in our study. First, the study was retrospective with no control group. The multicentric and international nature of the study, although a strong point, also implies the existence of divergences in care and techniques between the centers. The angiographic images were self-adjudicated and, therefore, the results might be less favorable after core laboratory adjudication.17 Furthermore, we included patients with occlusions of the anterior and posterior circulation, resulting in heterogeneity of the study population due to the worse outcome of posterior circulation strokes.18
Conclusion
This multicenter study reports that ADAPT with the ARC catheter in large vessel occlusion stroke patients is effective and safe. The ADAPT approach with the ARC achieves an mTICI 2b–3 in more than 90% of cases. In unsuccessful cases of ADAPT, a stent retriever can easily be added to the treatment strategy leading to an overall success rate of more than 95%. Complication rates were in line with the literature reports of other aspiration catheters.
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
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