Amrendra Miranpuri

Bio: Amrendra Miranpuri is an academic researcher from Medical University of South Carolina. The author has contributed to research in topics: Balloon & Balloon catheter. The author has an hindex of 4, co-authored 5 publications receiving 362 citations.

Initial clinical experience with the ADAPT technique: a direct aspiration first pass technique for stroke thrombectomy

Abstract: Background The development of new revascularization devices has improved recanalization rates and time but not clinical outcomes. We report our initial results with a new technique utilizing a direct aspiration first pass technique with a large bore aspiration catheter as the primary method for vessel recanalization. Methods A retrospective evaluation of a prospectively captured database of 37 patients at six institutions was performed on patients where the ADAPT technique was utilized. The data represent the initial experience with this technique. Results The ADAPT technique alone was successful in 28 of 37 (75%) cases although six cases had large downstream emboli that required additional aspiration. Nine cases required the additional use of a stent retriever and one case required the addition of a Penumbra aspiration separator to achieve recanalization. The average time from groin puncture to at least Thrombolysis in Cerebral Ischemia (TICI) 2b recanalization was 28.1 min, and all cases were successfully revascularized. TICI 3 recanalization was achieved 65% of the time. On average, patients presented with an admitting National Institutes of Health Stroke Scale (NIHSS) score of 16.3 and improved to an NIHSS score of 4.2 by the time of hospital discharge. There was one procedural complication. Discussion This initial experience highlights the fact that the importance of the technique with which new stroke thrombectomy devices are used may be as crucial as the device itself. The ADAPT technique is a simple and effective approach to acute ischemic stroke thrombectomy. Utilizing the latest generation of large bore aspiration catheters in this fashion has allowed us to achieve excellent clinical and angiographic outcomes.

Combined balloon stent technique with the Scepter C balloon and low-profile visualized intraluminal stent for the treatment of intracranial aneurysms

Abstract: Background The ‘balloon-then-stent’ method involves stent placement after completion of a balloon-assisted embolization. The drawback to this technique is that the coil mass achieved during balloon remodeling must be crossed prior to stent deployment. This additional maneuver introduces the potential risk of coil disruption. We describe the first report of a novel technique employing the ‘balloon-then-stent’ method. Methods A 51-year-old patient with an unruptured right middle cerebral artery bifurcation aneurysm was treated with balloon remodeling employing a 4×10 mm Scepter C balloon catheter. Following coil embolization, a low-profile visualized intraluminal stent (LVIS) Jr 2.5 mm×16 mm was delivered via the coaxial balloon catheter and deployed across the aneurysm neck. Results Follow-up angiograms demonstrated that the coil mass was well-seated within the aneurysm sac and the parent vessel was widely patent with satisfactory vessel wall apposition by the stent. Conclusions We describe a technique for balloon remodeling followed by stenting for aneurysm coil embolization that incorporates the use of a coaxial dual-lumen balloon catheter system through which a novel self-expanding stent can be deployed. In the case described, we found this technique to be safe and feasible, reducing both the number of steps involved in this technique and the opportunities for mechanical coil-related complications.

Balloon remodeling for aneurysm coil embolization with the coaxial lumen Scepter C balloon catheter: initial experience at a high volume center

Abstract: Introduction The use of balloon remodeling allows for the treatment of aneurysms that were previously considered to be poor candidates for coil embolization. The Scepter C (Microvention, Tustin, California, USA) is a novel temporary occlusion balloon system with a dual coaxial lumen catheter. The design accommodates a more steerable 0.014 inch guidewire with improved control for delivery to the target lesion. We describe our initial experience with the use of this device for balloon remodeling to assist during aneurysm coil embolization. Methods All aneurysms that were treated with balloon remodeling employing the Scepter C balloon at a single institution (Medical University of South Carolina) from the time it was available in October 2011 to July 2012 were evaluated. Patient demographics, aneurysm characteristics, procedural success, and adverse events were assessed. Results 52 aneurysms were treated in 48 patients (45 women, three men) with a mean age of 59.3±11 years (mean±SD). Mean aneurysm height was 5.9±3 mm, width 4.4±2 mm with a 3.1±2 mm broad neck. A variety of aneurysms were treated. The most commonly utilized size was the 4 mm×10 mm (n=33) balloon. A Raymond 1 (complete occlusion) was achieved in the majority (n=44; 84.6%) of aneurysms, Raymond 2 (residual neck) in five, and Raymond 3 (residual aneurysm) in five. There was one complication (1.9%) attributed directly to balloon use. Conclusions Our initial experience with the dual coaxial lumen Scepter C occlusion balloon catheter demonstrates its feasibility for use in balloon remodeling for aneurysm coil embolization. A variety of aneurysms at different locations were treated with satisfactory initial angiographic results and adverse event rates.

Balloon augmented Onyx embolization utilizing a dual lumen balloon catheter: utility in the treatment of a variety of head and neck lesions

Abstract: Introduction Endovascular embolization for tumors and vascular malformations has emerged as an important preoperative adjunct prior to resection. We describe the advantages of utilizing a recently released dual lumen balloon catheter for ethylene vinyl alcohol copolymer, also known as Onyx (ev3, Irvine, California, USA), embolization for a variety of head and neck pathologies. Methods A retrospective review of all cases utilizing the Scepter C balloon catheter (MicroVention Inc, Tustin, California, USA) for use in balloon augmented embolization was performed over a 4 month period from October 2012 to February 2013 at the Medical University of South Carolina, Charleston, South Carolina, USA. Charts and angiographic images were reviewed. Representative cases involving diverse pathologies are summarized and illustrate the observed advantages of balloon augmented Onyx embolization with a dual lumen balloon catheter. Case illustrations Balloon augmented Onyx embolization utilizing a novel dual lumen balloon catheter was employed to treat both ruptured and unruptured arteriovenous malformations, intracranial dural arteriovenous fistulae, intracranial neoplasms, carotid body tumors, a thyroid mass, and an extracranial arteriovenous fistula. Conclusions The dual lumen balloon catheter has several advantages for use with Onyx embolization over older devices, including more efficient proximal plug formation and enhanced navigability for placement deep within the pedicles. The balloon augmented Onyx embolization technique represents a valuable tool to add to the armamentarium of the neurointerventionalist to address a variety of head and neck lesions.

Stenting of Dural Sinuses for Pseudotumor Cerebri: The "Conduit" Technique

Abstract: Introduction: Carefully selected pseudotumor cerebri patients with dural sinus stenosis and pressure gradients can be considered for sinus stenting. The tortuous sigmoid sinus-jugular bulb junction and transverse-sigmoid sinus stenosis can contribute to the complexity of stent delivery. Materials and Results: Novel, distal access guide catheters such as 6 Fr 070 Neuron and 6 Fr Chaperon (Microvention-Terumo, Irvine, CA), and the 6 Fr 088 Neuron Max sheath (Penumbra, Inc. , Alameda, CA), over a diagnostic insert catheter can provide distal access to the dural sinuses and provide a stable platform for the delivery of relatively stiff carotid stents. We report a technical nuance, “the conduit technique” that facilitated the deployment of a carotid stent to the dural sinus in nineteen cases No guide catheter or stent complications were encountered in our series. Conclusion: We outline our “conduit” approach in sinus stenting using distal access guide catheters which allows for superior navigability and trackability of the guide catheters across the tortuous and stenotic sinus system with successful deployment of a carotid stent.

Effect of Endovascular Contact Aspiration vs Stent Retriever on Revascularization in Patients With Acute Ischemic Stroke and Large Vessel Occlusion: The ASTER Randomized Clinical Trial.

Abstract: Importance The benefits of endovascular revascularization using the contact aspiration technique vs the stent retriever technique in patients with acute ischemic stroke remain uncertain because of lack of evidence from randomized trials. Objective To compare efficacy and adverse events using the contact aspiration technique vs the standard stent retriever technique as a first-line endovascular treatment for successful revascularization among patients with acute ischemic stroke and large vessel occlusion. Design, Setting, and Participants The Contact Aspiration vs Stent Retriever for Successful Revascularization (ASTER) study was a randomized, open-label, blinded end-point clinical trial conducted in 8 comprehensive stroke centers in France (October 2015-October 2016). Patients who presented with acute ischemic stroke and a large vessel occlusion in the anterior circulation within 6 hours of symptom onset were included. Interventions Patients were randomly assigned to first-line contact aspiration (n = 192) or first-line stent retriever (n = 189) immediately prior to mechanical thrombectomy. Main Outcomes and Measures The primary outcome was the proportion of patients with successful revascularization defined as a modified Thrombolysis in Cerebral Infarction score of 2b or 3 at the end of all endovascular procedures. Secondary outcomes included degree of disability assessed by overall distribution of the modified Rankin Scale (mRS) score at 90 days, change in National Institutes of Health Stroke Scale (NIHSS) score at 24 hours, all-cause mortality at 90 days, and procedure-related serious adverse events. Results Among 381 patients randomized (mean age, 69.9 years; 174 women [45.7%]), 363 (95.3%) completed the trial. Median time from symptom onset to arterial puncture was 227 minutes (interquartile range, 180-280 minutes). For the primary outcome, the proportion of patients with successful revascularization was 85.4% (n = 164) in the contact aspiration group vs 83.1% (n = 157) in the stent retriever group (odds ratio, 1.20 [95% CI, 0.68-2.10]; P = .53; difference, 2.4% [95% CI, −5.4% to 9.7%]). For the clinical efficacy outcomes (change in NIHSS score at 24 hours, mRS score at 90 days) and adverse events, there were no significant differences between groups. Conclusions and Relevance Among patients with ischemic stroke in the anterior circulation undergoing thrombectomy, first-line thrombectomy with contact aspiration compared with stent retriever did not result in an increased successful revascularization rate at the end of the procedure. Trial Registration clinicaltrials.gov Identifier:NCT02523261

ADAPT FAST study: a direct aspiration first pass technique for acute stroke thrombectomy

Abstract: Background The development of new revascularization devices has improved recanalization rates and time, but not clinical outcomes. We report a prospectively collected clinical experience with a new technique utilizing a direct aspiration first pass technique with large bore aspiration catheter as the primary method for vessel recanalization. Methods 98 prospectively identified acute ischemic stroke patients with 100 occluded large cerebral vessels at six institutions were included in the study. The ADAPT technique was utilized in all patients. Procedural and clinical data were captured for analysis. Results The aspiration component of the ADAPT technique alone was successful in achieving Thrombolysis in Cerebral Infarction (TICI) 2b or 3 revascularization in 78% of cases. The additional use of stent retrievers improved the TICI 2b/3 revascularization rate to 95%. The average time from groin puncture to at least TICI 2b recanalization was 37 min. A 5MAX demonstrated similar success to a 5MAX ACE in achieving TICI 2b/3 revascularization alone (75% vs 82%, p=0.43). Patients presented with an admitting median National Institutes of Health Stroke Scale (NIHSS) score of 17.0 (12.0–21.0) and improved to a median NIHSS score at discharge of 7.3 (1.0–11.0). Ninety day functional outcomes were 40% (modified Rankin Scale (mRS) 0–2) and 20% (mRS 6). There were two procedural complications and no symptomatic intracerebral hemorrhages. Discussion The ADAPT technique is a fast, safe, simple, and effective method that has facilitated our approach to acute ischemic stroke thrombectomy by utilizing the latest generation of large bore aspiration catheters to achieve previously unparalleled angiographic outcomes.

Aspiration Thrombectomy after Intravenous Alteplase Versus Intravenous Alteplase Alone

Abstract: Background and Purpose—Thrombectomy, primarily with stent retrievers with or without adjunctive aspiration, provided clinical benefit across multiple prospective randomized trials. Whether this benefit is exclusive to stent retrievers is unclear. Methods—THERAPY (The Randomized, Concurrent Controlled Trial to Assess the Penumbra System’s Safety and Effectiveness in the Treatment of Acute Stroke; NCT01429350) was an international, multicenter, prospective, randomized (1:1), open label, blinded end point evaluation, concurrent controlled clinical trial of aspiration thrombectomy after intravenous alteplase (IAT) administration compared with intravenous-alteplase alone in patients with large vessel ischemic stroke because of a thrombus length of ≥8 mm. The primary efficacy end point was the percent of patients achieving independence at 90 days (modified Rankin Scale score, 0–2; intention-to-treat analysis). The primary safety end point was the rate of severe adverse events (SAEs) by 90 days (as treated analy...

Risk of distal embolization with stent retriever thrombectomy and ADAPT

Abstract: Background There is a discrepancy in clinical outcomes and the achieved recanalization rates with stent retrievers in the endovascular treatment of ischemic stroke. It is our hypothesis that procedural release of embolic particulate may be one contributor to poor outcomes and is a modifiable risk. The goal of this study is to assess various treatment strategies that reduce the risk of distal emboli. Methods Mechanical thrombectomy was simulated in a vascular phantom with collateral circulation. Hard fragment-prone clots (HFC) and soft elastic clots (SECs) were used to generate middle cerebral artery (MCA) occlusions that were retrieved by the Solitaire FR devices through (1) an 8 Fr balloon guide catheter (BGC), (2) a 5 Fr distal access catheter at the proximal aspect of the clot in the MCA (Solumbra), or (3) a 6 Fr guide catheter with the tip at the cervical internal carotid artery (guide catheter, GC). Results from mechanical thrombectomy were compared with those from direct aspiration using the Penumbra 5MAX catheter. The primary endpoint was the size distribution of emboli to the distribution of the middle and anterior cerebral arteries. Results Solumbra was the most efficient method for reducing HFC fragments (p 1000 µm) was significantly increased using GC. A non-statistically significant benefit of direct aspiration was observed in several subgroups of emboli with size 50–1000 µm. However, compared with the stent-retriever mechanical thrombectomy techniques, direct aspiration significantly increased the risk of SEC fragmentation ( Conclusions The risk of distal embolization is affected by the catheterization technique and clot mechanics.