Dapeng Mo

Outcomes of tailored angioplasty and/or stenting for symptomatic intracranial atherosclerosis: a prospective cohort study after SAMMPRIS

Background and purpose High periprocedural complication rate is a key limitation of endovascular treatment of intracranial atherosclerotic disease (ICAD), despite potential risk reduction of recurrent stroke. Taking lessons from the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Arterial Stenosis (SAMMPRIS) trial, targeting a selected patient population, we prospectively evaluated the feasibility and safety of tailored angioplasty and/or stenting for patients with ICAD. Methods From November 2011 to October 2012, 158 patients with symptomatic ICAD caused by hypoperfusion combined with poor collateral flow were consecutively recruited into a prospective single center study. Patients were divided into three groups based on arterial access and lesion morphology: balloon mounted stent group (group BS) for smooth access and Mori A lesion, angioplasty plus self-expanding stent group (group AS) for tortuous access and Mori B or C lesion, and angioplasty group (group AG) for tortuous access and Mori A lesion. The primary endpoints were successful procedure rate and any vascular event within 30 days. Results Overall technical success rate was 96.3% (154/158). There were significant differences in the technical success rate: 89.7% (35/39) in group AG compared with 97.5% (79/81) in group BS and 100% (38/38) in group AS (p=0.042). The 30 day composite stroke, myocardial infarction, or death rate was 4.4% (7/158). Stroke within 30 days occurred in four patients in group BS and in three patients in group AS. Conclusions Individualized treatment of ICAD using tailored devices according to arterial access and lesion morphology was feasible and safe in symptomatic patients caused by hypoperfusion with poor collateral flow.

Association of PON1, P2Y12 and COX1 with Recurrent Ischemic Events in Patients with Extracranial or Intracranial Stenting

Background and Purpose Short-term combined use of clopidogrel and aspirin improves cerebrovascular outcomes in patients with symptomatic extracranial or intracranial stenosis. Antiplatelet non-responsiveness is related to recurrent ischemic events, but the culprit genetic variants responsible for the non-responsiveness have not been well studied. We aimed to identify the genetic variants associated with poor clinical outcomes. Methods Patients with symptomatic extracranial or intracranial stenosis scheduled for stenting and receiving dual antiplatelets (clopidogrel 75 mg and aspirin 100 mg daily) for at least 5 days before intervention were enrolled. Ischemic events including recurrent transient ischemic attack, stroke, myocardial infarction, and vascular-related mortality within 12 months follow-up were recorded. We examined the influence of genetic polymorphisms on treatment outcome in our patients. Results A total of 268 patients were enrolled into our study and ischemic events were observed in 39 patients. For rs662 of paraoxonase 1 (PON1), allele C was associated with an increased risk of ischemic events (OR = 1.64, 95%CI = 1.03–2.62, P = 0.029). The A-allele carriers of rs2046934 of P2Y12 had a significant association with adverse events (OR = 2.01, 95%CI = 1.10–3.67, P = 0.041). The variant T-allele of cyclooxygenase-1 (COX1) rs1330344 significantly increased the risk of recurrent clinical events (OR = 1.85, 95%CI = 1.12–3.03, P = 0.017). The other single nucleotide polymorphism (SNP) had no association with ischemic events. Conclusions PON1, P2Y12 and COX1 polymorphisms were associated with poorer vascular outcomes. Testing for these polymorphisms may be valuable in the identification of patients at risk for recurrent ischemic events.

Combined Use of Mechanical Thrombectomy with Angioplasty and Stenting for Acute Basilar Occlusions with Underlying Severe Intracranial Vertebrobasilar Stenosis: Preliminary Experience from a Single Chinese Center

BACKGROUND AND PURPOSE: Acute basilar occlusions have a poor prognosis without recanalization. Many have underlying severe atherosclerotic intracranial stenosis coexisting with acute thrombosis, requiring treatment of both pathologies in the same session, though technical risks may be encountered. The purpose of this study was to evaluate the technical feasibility and safety of combined treatment by using stent retrievers for the thrombosis, together with angioplasty and stent placement for the underlying stenosis. MATERIALS AND METHODS: This was a retrospective review of 13 patients with basilar occlusions treated with thrombectomy by the Solitaire stent retriever and angioplasty and intracranial stent placement for underlying severe vertebrobasilar stenosis in the same session. Reperfusion was assessed in terms of the TICI score. Perioperative complications were recorded. Clinical outcomes were assessed by the NIHSS at discharge and the mRS on follow-up at 90 days. RESULTS: Of the 30 patients with acute basilar artery occlusions treated with stent retrievers during the study period, 18 had coexisting severe intracranial stenosis. Thirteen patients meeting the criteria for our study received combined mechanical thrombectomy and angioplasty with stent placement. The successful recanalization rate was 100%. Distal vessel embolizations occurred in 3 patients. There were 2 mortalities. On discharge, 10 patients (77%) had an improvement in NIHSS of ≥10 points. At 90 days, 6 patients (46%) had a good functional outcome with an mRS of ≤2. CONCLUSIONS: The combined use of mechanical thrombectomy with angioplasty and stent placement for acute basilar occlusions with underlying severe intracranial atherosclerotic stenosis is technically feasible and safe.

Endovascular Mechanical Thrombectomy with the Solitaire Device for the Treatment of Acute Basilar Artery Occlusion

OBJECTIVE To determine the safety and efficacy of endovascular treatment with the Solitaire device for acute basilar artery occlusion (ABAO) and identify factors affecting clinical outcomes. METHODS We enrolled 36 consecutive ABAO patients (aged 58.6 ± 8.10 years) who underwent mechanical thrombectomy with the Solitaire device. We analyzed baseline characteristics, mechanical thrombectomy results, and factors predicting clinical outcomes, which were assessed at 90 days. RESULTS The median prethrombectomy National Institutes of Health Stroke Scale (NIHSS) score was 25.50 (interquartile range: 21.00-29.00); the median prethrombectomy Glasgow Coma Scale (GCS) score was 8.00 (5.00-9.75). Thirty patients (83.3%) had atherosclerotic stenosis of the occluded artery, and 25 underwent angioplasty (69.4%). Recanalization was successful (Thrombolysis in Cerebral Infarction grade: 2b-3) in 34 patients (94.4%). Six symptomatic intracranial hemorrhages (16.67%) occurred. Favorable outcomes (modified Rankin scale [mRS] score: 0-2) were achieved in 27.8% patients (10/36). The overall mortality rate was 30.6% (11/36) at 90 days. On univariate analysis, low prethrombectomy GCS and high post-thrombectomy NIHSS scores were associated with poor outcomes (mRS score >2) and mortality. Prethrombectomy unconsciousness, onset-to-recanalization time > 10.5 hours, and severe stenosis were associated with poor outcomes. Age ≥ 60 years was associated with mortality. CONCLUSIONS Endovascular treatment with the Solitaire device yielded high recanalization rates in ABAO patients and favorable clinical outcomes in approximately one third of patients. Intracranial stenosis was the main cause of occlusion. Angioplasty was commonly performed during mechanical thrombectomy to improve recanalization and prognosis. Early recanalization and better prethrombectomy status predicted better outcomes.

Protocol for a prospective, multicentre registry study of stenting for symptomatic intracranial artery stenosis in China

Introduction The SAMMPRIS trial suggested that aggressive treatment was superior to endovascular stenting in patients with severe symptomatic intracranial atherosclerotic stenosis (ICAS) due to high complication rates in patients in the stenting group. Given that 12.2% patients failed aggressive medical therapy in the SAMMPRIS study, it is imperative to perform a multicentre prospective registry study of stenting for patients with ICAS in China. This study aims to evaluate the safety and efficacy of endovascular stenting for patients with symptomatic intracranial artery stenosis and poor collaterals in China and to identify the characteristics of the population that would benefit the most from endovascular stenting in Chinese patients. Methods and analysis This multicentre prospective registry study will involve 20 stroke centres in China, and plans to recruit 300 patients into the registry. Patients with ≥70% stenosis and symptomatic intracranial atherosclerotic disease caused by hypoperfusion combined with poor collaterals who met the inclusion criteria and exclusion criteria would be enrolled for this study. The primary outcome is the target vessel stroke event (including haemorrhagic or ischaemic stroke) or death within 30 days after stenting. The secondary outcomes include the successful recanalisation rate, the incidence of recurrent ischaemic stroke in the territory of the stented artery between 30 days and 1 year postoperatively, the restenosis rate and health-related quality of life. Ethics and dissemination The protocol is approved by the ethics committee at the coordinating centre and by the local institutional review board at each participating centre. Findings will be shared with participating hospitals, policymakers and the academic community to promote quality monitoring, quality improvement and the efficient allocation and use of cerebral catheterisation and intracranial artery stenting in China. Trial registration number http://www.clinicaltrials.gov (NCT01968122).

Endovascular recanalization for chronic symptomatic middle cerebral artery total occlusion

The optimal treatment of chronic middle cerebral artery (MCA) occlusion is unclear. Angioplasty and stenting may be an alternative treatment for patients with recurrent ischemic symptoms despite medical therapy. Two patients with chronic right MCA occlusion successfully treated with stenting are reported, together with their long term follow-up to illustrate the feasibility of endovascular recanalization. One patient remained asymptomatic at the 29-month follow-up. Another patient developed symptomatic in-stent restenosis at 12 months which resolved after repeat angioplasty. Further larger scale pilot studies are needed to determine the efficacy and long term outcome of this treatment.

Association of thrombelastographic parameters with post-stenting ischemic events

Background and purpose Thrombelastography (TEG) is widely used for the measurement of platelet function. However, few studies have investigated the TEG parameters in patients receiving extracranial or intracranial artery stenting for ischemic cerebrovascular disease. This study sought to describe the association of TEG parameters before the procedure with post-procedural ischemic events after extracranial or intracranial artery stenting. Methods Patients in whom stenting was performed for extracranial or intracranial artery stenosis (70–99%) were recruited into the study. Blood samples were obtained for TEG to assess platelet function before stenting. The primary endpoint was ischemic stroke or transient ischemic attack in the territory of the stented artery. Results A total of 218 patients were included in the study. During a mean follow-up period of 132 days (range 98–226 days), 18 (8.3%) primary endpoint events were recorded. Compared with patients without ischemic events, the ADP-induced platelet-fibrin clot strength (MAADP) was significantly higher (41.57±15.10 vs 33.50±13.86, p=0.020) and the ADP inhibition rate (ADP%) was significantly lower in patients with ischemic events (39.54±23.15 vs 55.29±24.43, p=0.009). Multivariate analysis identified MAADP and ADP% as significant independent predictors of subsequent ischemic events with HRs of 1.036 and 0.965, respectively. From receiver operating characteristic curve analysis, MAADP >49.95 mm had the best predictive value of ischemic events. Conclusions Our study suggests that TEG parameters MAADP and ADP% are associated with subsequent ischemic events in patients with extracranial or intracranial stents. Clinical trial number NCT01925872.

Fractional Flow Assessment for the Evaluation of Intracranial Atherosclerosis: A Feasibility Study

Purpose: Current studies on endovascular intervention for intracranial atherosclerosis select patients based on luminal stenosis. Coronary studies demonstrated that fractional flow measurements assess ischemia better than anatomical stenosis and can guide patient selection for intervention. We similarly postulated that fractional flow can be used to assess ischemic stroke risk. Methods: This was a feasibility study to assess the technical use and safety of applying a pressure guidewire to measure fractional flow across intracranial stenoses. Twenty patients with severe intracranial stenosis were recruited. The percentage of luminal stenosis, distal to proximal pressure ratios (fractional flow) and the fractional flow gradients across the stenosis were measured. Procedural success rate and safety outcomes were documented. Results: All 20 patients had successful crossing of stenosis by the pressure guidewire. Ten patients underwent angioplasty, and 5 had stenting performed. There was one perforator stroke, but not related to the use of the pressure wire. For the 13 patients with complete pre- and postintervention data, the mean preintervention stenosis, fractional flow and translesional pressure gradient were 76.2%, 0.66 and 29.9 mm Hg, whilst the corresponding postintervention measurements were 24.7%, 0.88 and 10.9 mm Hg, respectively. Fractional flow (r = -0.530, p = 0.001) and the translesional pressure gradient (r = 0.501, p = 0.002) only had a modest correlation with the luminal stenosis. Conclusion: Fractional flow measurement by floating a pressure guidewire across the intracranial stenosis was technically feasible and safe in this study. Further studies are needed to validate its use for ischemic stroke risk assessment.

The long term results of vertebral artery ostium stenting in a single center

Background and purpose The long term results of vertebral artery ostium (VAO) stenting remain uncertain. We sought to evaluate the incidence and risk factors for recurrent ischemic events on long term follow-up in patients who have undergone VAO stenting. Methods 190 consecutive patients who had undergone a total of 202 stenting procedures for symptomatic atherosclerotic VAO stenosis between January 2011 and December 2012 were screened. Baseline demographics of the patients and morphological features of VAO were recorded. The primary outcome events analyzed included recurrent transient ischemic attack (TIA), stroke, and vascular related mortality. Risk factors for these recurrent events were identified. Other outcome events analyzed included in-stent restenosis (ISR) ≥50% and stent fracture noted on follow-up. Results Of the 188 patients with available follow-up data (mean follow-up period 16.7 months), 34 patients suffered recurrent TIAs (18.1%); none had stroke or death. 40 patients were found to have ISR (21.2%) and nine patients had stent fracture (4.7%). Patients with recurrent events were significantly more likely to have ISR, stent fracture, vessel tortuosity, and hyperlipidemia than patients without recurrent events. Conclusions Stenting for VAO stenosis seems to be safe and efficacious. The majority of recurrent events were TIAs, which may be related to ISR, stent fracture, vessel tortuosity, and hyperlipidemia.

Selective use of transradial access for endovascular treatment of severe intracranial vertebrobasilar artery stenosis

OBJECTIVE To study the feasibility and safety of transradial artery access for endovascular intervention of severe intracranial vertebrobasilar stenosis for selected patients not suitable for transfemoral access. METHODS This was a retrospective analysis of 58 patients who had undergone intervention for severe intracranial vertebrobasilar stenosis using transradial access between January 2012 and September 2014. The reasons for transradial access were traced. The outcome measures were the technical success rate, 30-day stroke or death in the territory of the culprit artery, periprocedural and access site complication rates. RESULTS Out of the 58 patients, 19 patients (32.8%) used the transradial approach due to poor iliofemoral artery access, 28 (48.3%) due to unfavorable brachiocephalic or subclavian artery anatomy, 11 (19%) due to unfavorable vertebral artery anatomy. The technical success rate was 100%. There were four periprocedural complications, one of which was asymptomatic. The 30-day stroke rate was 5.2% (3/58 patients), with two of them having no residual neurological deficits. There was no mortality. None had access site complications. CONCLUSIONS For selected patients with severe intracranial vertebrobasilar stenosis with difficult femoral access or anatomical variations precluding provision of a stable support for intracranial intervention, the transradial approach was shown to be a safe and feasible alternative route of access. Future trials of endovascular treatment for intracranial posterior circulation strokes should take into account the route of access.