Muhammad Zeeshan Memon

Occurrence and Predictors of Futile Recanalization following Endovascular Treatment among Patients with Acute Ischemic Stroke: A Multicenter Study

BACKGROUND AND PURPOSE: Although recanalization is the goal of thrombolysis, it is well recognized that it fails to improve outcome of acute stroke in a subset of patients. Our aim was to assess the rate of and factors associated with “futile recanalization,” defined by absence of clinical benefit from recanalization, following endovascular treatment of acute ischemic stroke. MATERIALS AND METHODS: Data from 6 studies of acute ischemic stroke treated with mechanical and/or pharmacologic endovascular treatment were analyzed. “Futile recanalization” was defined by the occurrence of unfavorable outcome (mRS score of ≥3 at 1–3 months) despite complete angiographic recanalization (Qureshi grade 0 or TIMI grade 3). RESULTS: Complete recanalization was observed in 96 of 270 patients treated with IA thrombolysis. Futile recanalization was observed in 47 (49%). In univariate analysis, patients with futile recanalization were older (73 ± 11 versus 58 ± 15 years, P < .0001) and had higher median initial NIHSS scores (19 versus 14, P < .0001), more frequent BA occlusion (17% versus 4%, P = .049), less frequent MCA occlusion (53% versus 76%, P = .032), and a nonsignificantly higher rate of symptomatic hemorrhagic complications (2% versus 9%, P = .2). In logistic regression analysis, futile recanalization was positively associated with age >70 years (OR, 4.4; 95% CI, 1.9–10.5; P = .0008) and initial NIHSS score 10–19 (OR, 3.8; 95% CI, 1.7–8.4; P = .001), and initial NIHSS score ≥20 (OR, 64.4; 95% CI, 28.8–144; P < .0001). CONCLUSIONS: Futile recanalization is a relatively common occurrence following endovascular treatment, particularly among elderly patients and those with severe neurologic deficits.

Comparison of Primary Angioplasty With Stent Placement for Treating Symptomatic Intracranial Atherosclerotic Diseases A Multicenter Study

Background and Purpose— We sought to compare the clinical outcomes between primary angioplasty and stent placement for symptomatic intracranial atherosclerosis. Methods— We retrospectively analyzed the clinical and angiographic data of 190 patients treated with 95 primary angioplasty procedures and 98 intracranial stent placements (total of 193 procedures) in 3 tertiary care centers. Stroke and combined stroke and/or death were identified as primary clinical end points during the periprocedural and follow-up period of 5 years. The rates of significant postoperative residual stenosis (≥50% of greater stenosis immediately after the procedure) and binary restenosis (≥50% stenosis at follow-up angiography within 3 years) were also compared. The comparative analysis was performed after adjusting for age, sex, and center. Results— Fourteen procedures in the angioplasty-treated group (15%) and 4 in the stent-treated group (4.1%) had significant postoperative residual stenosis (relative risk [RR]=2.8, 95% CI, 0.85 to 9.5, P=0.09, for the adjusted model). There were 3 periprocedural deaths (1.5%), 1 in the angioplasty group (1.1%) and 2 in the stent-treated group (2.0%) and 14 periprocedural strokes (7.3%), 7 periprocedural strokes in each group (7.4% and 7.1%, respectively; hazard ratio=1.1; 95% CI, 0.57 to 1.9, P=0.85). Angiographic follow-up was available for 134 procedures (66 angioplasty-treated and 68 stent-treated cases). Forty-eight procedures (36.1%) had evidence of binary restenosis (25 of 66 angioplasties, 23 of 68 stents, P=0.85). Binary restenosis-free survival at 12 months was 68% for the angioplasty-treated group and 64% for the stent-treated group. There was no difference in follow-up survival (stroke, or stroke and/or death) between the angioplasty-treated and the stent-treated groups (hazard ratio=0.54; 95% CI, 0.11 to 2.5, P=0.44 and hazard ratio=0.50; 95%, CI 0.17 to 1.5, P=0.22, respectively, after adjusting for age, sex, and center). The stroke- and/or death-free survival at 2 years for the angioplasty-treated group and the stent-treated group was 92±4% and 89±5%, respectively. Conclusions— Stent treatment for intracranial atherosclerosis may lower the rate of significant postoperative residual stenosis compared with primary angioplasty alone. No benefit of stent placement over primary angioplasty in reducing stroke or stroke and/or death could be identified in this study.

Comparison between primary angioplasty and stent placement for symptomatic intracranial atherosclerotic disease: meta-analysis of case series.

OBJECTIVETo compare the short- and long-term rates of stroke-and/or-death associated with primary angioplasty alone and angioplasty with stent placement using a meta-analysis of published studies. Both primary angioplasty alone and angioplasty with stent placement have been proposed as treatment strategies for symptomatic intracranial atherosclerotic disease to reduce the risk of stroke-and/or-death with best medical treatment alone. However, it remains unclear which of these endovascular techniques offers the best risk reduction. METHODSWe identified pertinent studies published between January 1980 and May 2008 using a search on PubMed and Cochrane libraries, supplemented by a review of bibliographies of selected publications. The incidences of stroke-and/or-death were estimated for each report and pooled for both angioplasty alone and angioplasty with stent placement at 1 month and 1 year postintervention and then compared using a random-effects model. The association of year of publication and 1-year incidence of stroke-and/or-death was analyzed with meta-regression. RESULTSAfter applying our selection criteria, we included 69 studies (33 primary angioplasty-alone studies [1027 patients] and 36 studies of angioplasty with stent placement [1291 patients]) in the analysis. There were a total of 91 stroke-and/or-deaths reported in the angioplasty-alone–treated group (8.9%; 95% confidence interval [CI], 7.1%–10.6%), compared with 104 stroke-and/or-deaths in the angioplasty-with-stent–treated group (8.1%; 95% CI, 6.6%–9.5%) during a 1-month period (relative risk [RR], 1.1; P = 0.48). The pooled incidence of 1-year stroke-and/or-death in patients treated with angioplasty alone was 19.7% (95% CI, 16.6%–23.5%), compared with 14.2% (95% CI, 11.9%–16.9%) in the angioplasty-with-stent–treated patients (RR, 1.39; P = 0.009). The incidence of technical success was 79.8% (95% CI, 74.7%–84.8%) in the angioplasty-alone group and 95% (95% CI, 93.4%–96.6%) in the angioplasty-with-stent–treated group (RR, 0.84; P < 0.0001). The pooled restenosis rate was 14.2% (95% CI, 11.8–16.6%) in the angioplasty-alone group, as compared with 11.1% (95% CI, 9.2%–13.0%) in the angioplasty-with-stent–treated group (RR, 1.28; P = 0.04). There was no effect of the publication year of the studies on the risk of stroke-and/or-death. CONCLUSIONRisk of 1-year stroke-and/or-death and rate of angiographic restenosis may be lower in symptomatic intracranial atherosclerosis patients treated by angioplasty with stent placement compared with patients treated by angioplasty alone.

Comparison of Partial (.6 mg/kg) versus Full‐Dose (.9 mg/kg) Intravenous Recombinant Tissue Plasminogen Activator Followed by Endovascular Treatment for Acute Ischemic Stroke: A Meta‐Analysis

In the treatment of acute ischemic stroke, intravenous (IV) recombinant tissue plasminogen (rt‐PA) and intraarterial (IA) interventions are often combined. However, the optimal dose of IV rt‐PA preceding endovascular treatment has not been established.

Safety and feasibility of intraarterial eptifibatide as a revascularization tool in acute ischemic stroke

OBJECT Experience with the use of platelet glycoprotein (GP) IIb-IIIa inhibitor eptifibatide in patients with ischemic stroke is limited. The authors report the off-label use of intraarterial eptifibatide during endovascular ischemic stroke revascularization procedures for reocclusion after documented recanalization or formed fresh thrombi in distal vessels that were inaccessible to endovascular devices. METHODS Patients who received intraarterial eptifibatide were identified from a prospectively collected database of patients in whom endovascular revascularization for acute ischemic stroke was attempted between 2005 and 2008. Data were analyzed retrospectively. The intraarterial eptifibatide dose was a single-bolus dose of 180 μg/kg body weight. Primary outcome measures were angiographic recanalization (Thrombolysis in Myocardial Infarction Grade 2 or 3), symptomatic intracranial hemorrhage rate, overall mortality rate, and favorable 3-month modified Rankin Scale score (≤ 2). RESULTS The study included 35 patients (mean age 62 years, range 18-85 years). The median presenting National Institutes of Health Stroke Scale score was 13. Two patients received intravenous tissue plasminogen activator before endovascular therapy. The median time from symptom onset to therapy initiation was 230 minutes (range 90-1370 minutes). Twelve patients (34%) received intraarterial tissue plasminogen activator without mechanical measures. Mechanical revascularization measures used were Merci retriever in 19 (54%), Penumbra device in 1 (3%), balloon angioplasty in 15 (43%), and stent placement in 22 (63%) patients. The mean dose of intraarterial eptifibatide was 11.6 mg (range 5-16.6 mg). Partial-to-complete recanalization (Thrombolysis in Myocardial Infarction Grade 2 or 3) was achieved in 27 patients (77%). Postprocedure intracranial hemorrhage occurred in 13 patients (37%), causing symptoms in 5 (14%). In the 5 symptomatic intracranial hemorrhage cases, all patients but one presented more than 8 hours after symptom onset and all received intraarterial recombinant tissue plasminogen activator. The median discharge National Institutes of Health Stroke Scale score was 7 (range 0-17). At 3 months postprocedure, 21 patients (60%) had a modified Rankin Scale score ≤ 2, and 8 patients (23%) had died. CONCLUSIONS Adjunctive intraarterial eptifibatide is a feasible option for salvage of reocclusion and thrombolysis of distal inaccessible thrombi during endovascular stroke revascularization. Its safety and efficacy need to be studied further in larger, multicenter, controlled studies.

Initial experience in establishing an academic neuroendovascular service: program building, procedural types, and outcomes.

To report our initial experience in setting up a neuroendovascular service in a university‐based comprehensive stroke center.

Intra‐Arterial Tenecteplase for Treatment of Acute Ischemic Stroke: Feasibility and Comparative Outcomes

Tenecteplase (TNK) is a third‐generation thrombolytic agent. We evaluated the safety and feasibility of intra‐arterial (IA) administration of TNK in patients with acute ischemic stroke.

Utility of Pharmacologic Provocative Neurological Testing Before Embolization of Occipital Lobe Arteriovenous Malformations

OBJECTIVE Endovascular treatment is an established option for treatment of cerebral arteriovenous malformations (AVMs). However, embolization has been associated with postprocedural neurological complications. We sought to evaluate the usefulness of intra-arterial pharmacologic provocative (superselective Wada) testing before embolization of occipital lobe AVMs. METHODS We performed a retrospective review of cases of occipital AVMs that were embolized at our institution (Millard Fillmore Gates Hospital) while the patient was under conscious sedation. Visual field testing was performed before and after superselective Wada testing and again after embolization. After microcatheterization of the target feeding pedicle, amobarbital (or, occasionally, methohexital) was administered, followed immediately by neurological testing. If the provocative test results were negative, the evaluated feeder was embolized with a liquid agent. Complications were categorized as transient or permanent neurological deficit, visual field loss, ischemic or hemorrhagic stroke, and death. RESULTS Thirteen patients with occipital AVMs underwent 39 Wada tests of 34 pedicles before embolization during 26 endovascular treatment sessions. Patients were treated under conscious sedation with local anesthesia. The mean age of these patients was 43.5 years (range 16-62 years); 6 were women. Testing induced a neurological deficit in six patients. A positive test result led us to abort embolization attempts in four pedicles. In the two remaining cases, advancement of the catheter tip distally within the feeding pedicle allowed us to proceed with embolization after initial test failure. Neither patient developed a visual field deficit after embolization. Despite passing the Wada test before embolization, one other patient had a visual deficit that was detected a few hours after the procedure; this deficit lessened but was permanent. No further ischemic complications and no hemorrhagic complications occurred. CONCLUSIONS Pharmacologic provocative testing is a useful and effective method of determining the safety of occipital AVM embolization. Our results support the performance of these procedures under conscious sedation.

Combined surgical and endovascular approach to treat symptomatic in-stent occlusion of the left common carotid artery origin: Technical note

Symptomatic occlusive lesions at the origins of the supra-aortic vessels pose challenges for treatment. Endovascular angioplasty and stent placement via the transfemoral approach is possible, but obtaining a stable position for the guide catheter via this approach is technically difficult. The authors describe the case of a 56-year-old man presenting with symptomatic occlusion of a previously placed stent at the origin of the left common carotid artery (CCA). An endovascular revascularization of the left CCA was planned. However, the absence of a lumen proximal to the stent prevented stable placement of a guide catheter via the transfemoral route. Consequently, the authors used a combined surgical and endovascular approach to gain access to the lesion. The left CCA was exposed surgically distal to the occlusion and clamped just proximal to its bifurcation to preserve flow from the external to the internal carotid artery (ICA) and to prevent embolism into the ICA. A wire was passed retrograde through the occlusive lesion and then was subsequently advanced proximally into the femoral sheath. This allowed transfemoral advancement of the appropriate endovascular devices to perform an angioplasty and placement of a stent. The patient remained neurologically stable, and postoperative studies showed improvement in cerebral perfusion. This case demonstrates the feasibility of distal-to-proximal stent delivery with a combined endovascular and surgical approach.