SS 611 - Stroke: endovascular treatment
Iatrogenic complications during mechanical thrombectomy for acute ischaemic stroke: potential mechanisms, rescue strategies, and clinical outcomes in a multicentre study
Purpose: Mechanical thrombectomy has emerged as valuable armamentarium for acute ischaemic stroke. Complications due to arterial rupture and dissection have not been formally described. This study aimed to report our intra-procedural vessel damage and discuss its technical details and clinical significance.
Methods and Materials: We studied patients prospectively included in SONIIA registry (2011-2015), a mandatory, externally audited registry that monitors the quality of reperfusion therapies in Catalonia during practice. Successful recanalisation (TICI grade ≥2b), procedural time, symptomatic intracranial haemorrhage (SICH), dramatic neurological improvement (≥10 points decrease in the NIHSS score at 24 hours), independent functional outcome (mRS ≤2) at three months, and iatrogenic arterial injury were recorded.
Results: Among the 1640 patients included, iatrogenic complications occurred in 3.6% (2.0% dissection, 1.6% perforation, 40% middle cerebral artery occlusion, 52.1% left side, 21.7% posterior circulation). Median NIHSS score was 17 (12-21) on arrival and 9 (3-18) at 24 hours. Complications were not related to general anaesthesia: 26.7% vs. 73.3% (RR, 1.7; 95% CI, 1.0-3.0; p=0.061). Complications were associated with less successful recanalisation: 36.7% vs. 79.3% (RR, 6.0; 95% CI, 3.6-10.1; p=0.000) and longer procedural time: 108.1±55.2 min vs. 87.4±73.32 min (p=0.031). SICH: 18.3% (81.8% perforation vs. 18.2% dissection, p=0.002) vs. 2.5% (p=0.000). Good early response: 15.1% vs. 71.0% (p=0.000). Functional independence: 18.4% vs. 48.9% (p=0.000). Mortality: 60.0% vs. 17.4% (p=0.000).
Conclusion: Intra-procedural vessel damage was rare, but when it occurred was associated with high unfavourable outcome. However, 18.4% had functional independence, suggesting that in some complicated patients good neurological recovery is achievable.
Purpose: The preponderance of evidence suggests that vessel location is an important predictors of outcomes in acute ischemic stroke. However, few studies have examined the natural history of a cohort of patients with persistent M2 vessel occlusion who would have been eligible for, but remained untreated with mechanical thrombectomy.
Methods and Materials: The SOS and FIRST trials were prospective, multicenter studies evaluating the natural history of a stroke cohort eligible for mechanical thrombectomy but did not receive the treatment. Enrolled patients presented with symptoms of acute ischaemic stroke due to large vessel occlusion and were refractory or ineligible for rtPA treatment. Functional independence was defined as a mRS score 0-2 at 90 days. Incidence of death, intracranial hemorrhage, serious adverse events, and mortality were assessed for association with vessel location.
Results: 238 patients (median age: 71) met study criteria. Occlusions of the M2 alone were reported in 8.9%. At 90 days only 75% of Middle Cerebral Artery M2 patients did not achieve functional independence as defined by a mRS score of 0-2. Mortality rate was 10%.
Conclusion: Persistent occlusion of the M2 MCA is associated with a low rate of functional independence and a high mortality, posing the question if this patient group should be considered for mechanical thrombectomy.
Manual aspiration thrombectomy using penumbra catheter in patients with acute migrated MCA occlusion
Purpose: Our study aimed to retrospectively assess the efficacy and safety of a manual aspiration thrombectomy (MAT) using Penumbra in patients with acute migrated middle cerebral artery (MCA) occlusion.
Methods and Materials: We conducted a retrospective review of patients who underwent MAT using Penumbra 4 or 5 MAX reperfusion catheters for treatment of acute MCA occlusion between January 2012 and December 2015. Migrated thrombus was defined as distal migration above> 1cm on initial cerebral angiography compared with preprocedural angiographic findings. We evaluated immediate angiographic results and clinical outcomes through reviewing of patient’s electrical medical records. We compared with clinical outcomes between migrated MCA occlusion and non-migrated MCA occlusions.
Results: During this period, 98 patients underwent MAT using Penumbra catheters for treatment of acute MCA occlusions. Of these patients, 19 (19.4%) had a migrated MCA thrombus on initial cerebral angiography compared with preprocedural angiographic findings. The overall rate of successful recanalisation (TICI grade ≥ 2b) was 90.8%. The rate of successful recanalisation on migrated thrombus group was 94.7% (18/19). Overall favourable clinical outcomes (mRS score at 3 months ≤ 2) were seen in 64 patients (65.3%). Although it is not significant, favourable clinical outcomes in migrated thrombus group was higher compared with non-migrated thrombus groups (78.9% vs. 60.8%, p = .231).
Conclusion: MAT appears to be safe and is capable of achieving high rate of successful recanalisation and favourable clinical outcomes in patients with acute MCA occlusion. A migrated thrombus group was more favorable clinical outcomes.
Single-centre experience using the 3MAX reperfusion catheter in the treatment of acute ischaemic stroke with distal arterial occlusion
Purpose: Recently published data reported promising results with tromboaspiration devices such as the Penumbra System (Penumbra, Alameda, California) combined with the Penumbra MAX series reperfusion catheters by using the ADAPT technique. The aim of this study was to report our initial experience with the 3MAX (3.8F) reperfusion catheter for the recanalisation of occluded distal intracranial arteries.
Methods and Materials: From August 2015 to December 2016, 28 consecutive patients (15 women [54%] and 13 men [46%]; mean age=69±18.7y, [range: 22-94]) for 34 distal occlusions underwent mechanical thrombectomy (MT) using the 3MAX catheter. The occluded vessels were: M2 (n=24; 70.6%), M3 (n=2; 5.9%), P1 (n=2, 5.9%), P2 (n=2, 5.9%), P3 (n=2, 5.9%), A3 (n=1, 2.9%) and superior cerebellar artery (SCA) (n=1, 2.9%). The primary endpoint was the Thrombolysis In Cerebral Infarction (TICI) score after thromboaspiration attempts alone using the 3MAX.
Results: In 1/34 (2.9%) cases, the 3MAX could not be navigated into the target artery. Successful recanalisation (TICI 2b/3) after aspiration with the 3MAX alone was achieved in 59% of the cases. Overall recanalisation rate was 76%. Six (17.6%) procedure-related complications occurred, including four (11.8%) 3MAX-related complications (two clot migration in the same territory; 2 clot migration in another territory). Overall mortality rate was 15.8%. No procedure-related mortality was recorded. mRS 0-2 was observed in 47.3% of the cases at last follow-up (average delay: 108±70 d).
Conclusion: The 3MAX reperfusion catheter is a safe device and provides interesting results for recanalisation of distal occlusions.
Comparison of dual-layer spectral CT with MRI in differentiation between haemorrhage and extravasation of iodinated contrast medium after endovascular treatment of ischaemic stroke
Purpose: To evaluate the advantages of dual-layer spectral omputed tomography (CT) for distinguishing between intracerebral haemorrhage and iodine extravasation due to disruption of the blood brain barrier in ischaemic stroke patients after mechanical thrombectomy.
Methods and Materials: Twenty patients who had received mechanical thrombectomy, were examined with a dual-layer spectral CT (IQon spectral CT, Philips Healthcare, USA) 11 +/- 3h after revascularisation. Virtual non-contrast (VNC) images and iodine overlay maps (IOM) were calculated and evaluated using a dedicated software (IntelliSpace Portal, Philips Healthcare, USA). Region of interests (ROIs) analyses were performed within the hyperdense areas in the conventional CT, IOM and VNC images. As a standard of reference data from Magnetic Resonance Imaging (MRI), acquired during the follow-up procedure, are utilised. Sensitivity, specificity and positive predictive value (PPV) for the presence of haemorrhage in dual-layer spectral CT are calculated.
Results: A total of twenty hyperdense areas in twelve patients were seen in dual-layer spectral CT. In comparison to follow-up MRI as a gold standard, it was possible to correctly classify haemorrhage (n=8), extravasation of iodine (n=8), or both (n=4) in spectral CT images. The ROI analysis showed HU of 64 +/- 2 (“conventional CT”) and 51 +/-2 (VNC) for haemorrhage and 61 +/- 3 (“conventional CT”) and 22 +/-2 (VNC) for iodine, respectively.
Conclusion: Dual-layer spectral CT improves the capability to distinguish between intracerebral haemorrhage and extravasation of iodinated contrast medium due to disrupted blood brain barrier in patients with acute stroke after intra-arterial thrombectomy.
Purpose: To assess the efficacy and safety of thrombo-aspiration (TA) using Penumbra catheters in patients with acute middle cerebral artery (MCA) occlusion.
Methods and Materials: We evaluated immediate angiographic results and prospective clinical outcomes after treatment of 33 consecutive patients undergoing endovascular treatment of MCA occlusions, treated with Penumbra aspiration catheters and pump system, between January 2015 and July 2016, involving 12 men and 21 women, with a median age of 69 years (range 25-88). Seventeen patients had left MCA arterial occlusion (52%). Inclusion criteria were defined as: patients with neurological symptoms (NIHSS≥6), treatment within 6 hours after symptom onset, brain CT scan showing infarct <50% MCA territory and catheter angiography showing thrombo-embolic MCA occlusion.
Results: Recanalisation by TA was achieved in 24 patients (73%), with successful recanalisation (TICI 2b/3) in 22 patients. Seven patients were additionally treated with stent retrievers (21%). In 9 patients TA was unsuccessful, because of access difficulties in tortuous arteries (n=4) or shortness of catheters (n=2), or impossibility to aspirate thrombus (n= 3). Except one carotid artery dissection and a thrombo-embolus in another vascular territory, no procedure related complications occurred. At admission, median NIHSS was 16 (range 6-29), with decrease to 10 at discharge (range 1-29). Median mRS at 3 months was 1 (range 0-6). Favorable clinical outcome at 3 months (mRS≤2) was seen in 21 patients (64%).
Conclusion: In our experience, catheter thrombo-aspiration is a safe procedure, with high rates of successful recanalisation and favorable clinical outcomes in patients with acute ischemic MCA stroke.
Purpose: To evaluate the safety and affectivity of primary aspiration technique in endovascular stroke treatment.
Methods and Materials: Between July 2014 and December 2015 107 acute ischaemic stroke patients with large vessel occlusion and mean NIHSS 14 were treated with primary aspiration technique. The ACE 64 aspiration catheter (Penumbra inc.) was used in all patients. Procedural and clinical data were selected for analysis.
Results: The primary aspiration technique was successful in achieving thrombolysis in cerebral infarction (TICI) 2b or 3 revascularization in 65% of cases. In 60% of these cases procedure time was <40min. The additional use of stent retrievers in 37 cases improved the TICI 2b/3 revascularisation rate to 89%. The functional outcome (modified Rankin Scale (mRS) 0-2) at discharge was 49.5 %, mRS 6 in 14%.
Conclusion: Primary aspiration technique is an alternative strategy for mechanical thrombectomy as it allows high recanalisation rates with small procedure times.
Purpose: Acute basilar artery (BA) occlusion is considered among the most severe medical conditions, with very high morbidity and mortality. The aim of this study is to present 5 years experience of 12 centers of the Lumbardy area of Italy, in BA occlusion endovascular treatment (EVT) and to evaluate prognostic factors that may improve clinical outcomes and recanalisation rate.
Methods and Materials: The RELOBA registry is a retrospective multicenter collection of basilar artery occlusion undergone to EVT in the period 2010-2015. 102 patients (mean age 65 years) with proven basilar artery occlusion treated with EVT were included. Clinical, procedure and neuroradiological data were collected. Recanalisation (TICI score 2b-3) was assessed by local interventional neuroradiologist. Good (moderate) outcome was defined as a mRS score of 0 to 2 (0-3) assessed at 3 months.
Results: 39% patients had good and 46% had moderate mRS clinical outcome at 3 months. Mortality was 30%. TICI 2b-3 recanalisation was achieved by 62%. Univariate analysis showed that age, NIHSS at onset, total time to recanalisation, recanalisation TICI grade were all statistically significant (p<0.05) in predicting clinical outcome. Multivariate logistic regression showed total time, age, NIHSS at onset as significant independent predictors of good outcome.
Conclusion: Mechanical thrombectomy is feasible and effective in patients with acute basilar artery occlusion. A better understanding of the factors that influence the prognosis could dramatically improve patient outcome. These initial results must be confirmed by further prospective studies within a randomised-controlled settings.
Low admission blood glucose favours good neurologic outcome and smaller final infarct size in stroke thrombectomy
Purpose: High levels of peripheral blood glucose on admission (AG) are associated with a deteriorated outcome in stroke. Different pathophysiologies have been suggested, including inhibitory effects on the efficacy of IV rtPA, blood-brain barrier breakdown and reduced salvage of the penumbra. The association of AG in the context of stroke thrombectomy has not been evaluated in detail up to date.
Methods and Materials: 325 consecutive patients with acute MCA occlusion undergoing mechanical thrombectomy (MT) between 2008 and 2016 were included in this retrospective study. AG was classified on an ordinal scale ranging from normoglycaemia to severe hyperglycaemia. Final infarct volume (FIV) was segmented on postinterventional, diffusion-weighted MR images. Short-term neurologic outcome was assessed using dichotomised NIHSS variables (good outcome: discharge-NIHSS <5; substantial improvement: compound criterion of either NIHSS at discharge ≤1 or NIHSS-improvement ≥8).
Results: Higher levels of AG were associated with older age, higher admission-NIHSS, larger FIV and more severe neurologic disability (all p<0.05). These associations were present in all subgroups, irrespective of recanalisation results, time to recanalisation and administration of IV rtPA bridging. Higher AG was found to be an independent risk factor for lower rates of good neurologic outcome and substantial neurologic improvement (aOR 0.744, 95%-CI: 0.568-0.975 and aOR 0.745, 95%-CI 0.600-0.925, respectively).
Conclusion: Higher levels of AG are significantly associated with a poor neurologic outcome in patients undergoing MCA-thrombectomy. These findings challenge the hypothesis that an association between acute hyperglycaemia and patients’ outcome may be mediated through altering the efficacy of thrombolysis and thereby favours others pathophysiologic explanations.
Impact of thrombectomy maneuver count on recanalisation and clinical outcome in patients with ischaemic stroke
Purpose: The effectiveness of thrombus retraction in patients with acute stroke using stent retrievers is variable. Here, we studied the impact of thrombectomy maneuver count on recanalisation and clinical outcome.
Methods and Materials: We retrospectively analysed data of 99 consecutive patients with acute occlusion of the terminal internal carotid artery or M1 segment of the middle cerebral artery treated with thrombectomy. Successful recanalisation was defined as TICI score of 2b or 3. Good clinical outcome was defined as mRS score of ≤2 at 90 days after stroke onset.
Results: Median thrombectomy maneuver count was 3 (range 1-10). Multivariate logistic regression analyses identified increasing maneuver count as an independent predictor of both unsuccessful recanalisation (adjusted OR 0.39, 95% confidence interval 0.22 to 0.59, P<0.001) and unfavorable clinical outcome (adjusted OR 0.56, 95% confidence interval 0.34 to 0.88, P=0.018). In cases where the thrombectomy procedure was finished within two maneuvers, a good outcome was significantly more likely compared to cases where three or four maneuvers or even more than four maneuvers were required (P<0.001). Besides, maneuver count was not associated with the occurrence of intraprocedural complications (unadjusted OR 1.01, 95% CI 0.99-1.03, P=0.436).
Conclusion: The number of thrombectomy maneuvers is strongly associated with the probability of successful recanalisation and good clinical outcome. A good outcome appears to be unlikely, if recanalisation is not achieved within four maneuvers.