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Dive into the research topics where Andrew Xavier is active.

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Featured researches published by Andrew Xavier.


Stroke | 2014

Balloon Guide Catheter Improves Revascularization and Clinical Outcomes With the Solitaire Device Analysis of the North American Solitaire Acute Stroke Registry

Thanh N. Nguyen; T Malisch; Alicia C. Castonguay; Rishi Gupta; Chung Huan J Sun; Coleman O. Martin; William E. Holloway; Nils Mueller-Kronast; Joey D. English; Italo Linfante; Guilherme Dabus; Franklin A. Marden; Hormozd Bozorgchami; Andrew Xavier; A Rai; Michael T. Froehler; Aamir Badruddin; M Taqi; Michael G. Abraham; Vallabh Janardhan; Hashem Shaltoni; Roberta Novakovic; Albert J. Yoo; Alex Abou-Chebl; Peng R. Chen; Gavin W. Britz; Ritesh Kaushal; Ashish Nanda; Mohammad A. Issa; Hesham Masoud

Background and Purpose— Efficient and timely recanalization is an important goal in acute stroke endovascular therapy. Several studies demonstrated improved recanalization and clinical outcomes with the stent retriever devices compared with the Merci device. The goal of this study was to evaluate the role of the balloon guide catheter (BGC) and recanalization success in a substudy of the North American Solitaire Acute Stroke (NASA) registry. Methods— The investigator-initiated NASA registry recruited 24 clinical sites within North America to submit demographic, clinical, site-adjudicated angiographic, and clinical outcome data on consecutive patients treated with the Solitaire Flow Restoration device. BGC use was at the discretion of the treating physicians. Results— There were 354 patients included in the NASA registry. BGC data were reported in 338 of 354 patients in this subanalysis, of which 149 (44%) had placement of a BGC. Mean age was 67.3±15.2 years, and median National Institutes of Health Stroke Scale score was 18. Patients with BGC had more hypertension (82.4% versus 72.5%; P=0.05), atrial fibrillation (50.3% versus 32.8%; P=0.001), and were more commonly administered tissue plasminogen activator (51.6% versus 38.8%; P=0.02) compared with patients without BGC. Time from symptom onset to groin puncture and number of passes were similar between the 2 groups. Procedure time was shorter in patients with BGC (120±28.5 versus 161±35.6 minutes; P=0.02), and less adjunctive therapy was used in patients with BGC (20% versus 28.6%; P=0.05). Thrombolysis in cerebral infarction 3 reperfusion scores were higher in patients with BGC (53.7% versus 32.5%; P<0.001). Distal emboli and emboli in new territory were similar between the 2 groups. Discharge National Institutes of Health Stroke Scale score (mean, 12±14.5 versus 17.5±16; P=0.002) and good clinical outcome at 3 months were superior in patients with BGC compared with patients without (51.6% versus 35.8%; P=0.02). Multivariate analysis demonstrated that the use of BGC was an independent predictor of good clinical outcome (odds ratio, 2.5; 95% confidence interval, 1.2–4.9). Conclusions— Use of a BGC with the Solitaire Flow Restoration device resulted in superior revascularization results, faster procedure times, decreased need for adjunctive therapy, and improved clinical outcome.


Journal of NeuroInterventional Surgery | 2014

North American Solitaire Stent Retriever Acute Stroke registry: post-marketing revascularization and clinical outcome results

Osama O. Zaidat; Alicia C. Castonguay; Rishi Gupta; Chung Huan J Sun; Coleman O. Martin; William E. Holloway; Nils Mueller-Kronast; Joey D. English; Italo Linfante; Guilherme Dabus; Tim W. Malisch; Franklin A. Marden; Hormozd Bozorgchami; Andrew Xavier; A Rai; Michael T. Froehler; Aamir Badruddin; Thanh N. Nguyen; M. Asif Taqi; Michael G. Abraham; Vallabh Janardhan; Hashem Shaltoni; Roberta Novakovic; Albert J. Yoo; Alex Abou-Chebl; Peng R. Chen; Gavin W. Britz; Ritesh Kaushal; Ashish Nanda; Mohammad A. Issa

Background Limited post-marketing data exist on the use of the Solitaire FR device in clinical practice. The North American Solitaire Stent Retriever Acute Stroke (NASA) registry aimed to assess the real world performance of the Solitaire FR device in contrast with the results from the SWIFT (Solitaire with the Intention for Thrombectomy) and TREVO 2 (Trevo versus Merci retrievers for thrombectomy revascularization of large vessel occlusions in acute ischemic stroke) trials. Methods The investigator initiated NASA registry recruited North American sites to submit retrospective angiographic and clinical outcome data on consecutive acute ischemic stroke (AIS) patients treated with the Solitaire FR between March 2012 and February 2013. The primary outcome was a Thrombolysis in Myocardial Ischemia (TIMI) score of ≥2 or a Treatment in Cerebral Infarction (TICI) score of ≥2a. Secondary outcomes were 90 day modified Rankin Scale (mRS) score, mortality, and symptomatic intracranial hemorrhage. Results 354 patients underwent treatment for AIS using the Solitaire FR device in 24 centers. Mean time from onset to groin puncture was 363.4±239 min, mean fluoroscopy time was 32.9±25.7 min, and mean procedure time was 100.9±57.8 min. Recanalization outcome: TIMI ≥2 rate of 83.3% (315/354) and TICI ≥2a rate of 87.5% (310/354) compared with the operator reported TIMI ≥2 rate of 83% in SWIFT and TICI ≥2a rate of 85% in TREVO 2. Clinical outcome: 42% (132/315) of NASA patients demonstrated a 90 day mRS ≤2 compared with 37% (SWIFT) and 40% (TREVO 2). 90 day mortality was 30.2% (95/315) versus 17.2% (SWIFT) and 29% (TREVO 2). Conclusions The NASA registry demonstrated that the Solitaire FR device performance in clinical practice is comparable with the SWIFT and TREVO 2 trial results.


Stroke | 2014

North American SOLITAIRE Stent-Retriever Acute Stroke Registry: choice of anesthesia and outcomes.

Alex Abou-Chebl; O Zaidat; Alicia C. Castonguay; Rishi Gupta; Chung Huan J Sun; Coleman O. Martin; William E. Holloway; Nils Mueller-Kronast; Joey D. English; Italo Linfante; Guilherme Dabus; T Malisch; Franklin A. Marden; Hormozd Bozorgchami; Andrew Xavier; A Rai; Micahel T. Froehler; Aamir Badruddin; Thanh N. Nguyen; M Taqi; Michael G. Abraham; Vallabh Janardhan; Hashem Shaltoni; Roberta Novakovic; Albert J. Yoo; Peng R. Chen; Gavin W. Britz; Ritesh Kaushal; Ashish Nanda; Mohammad A. Issa

Background and Purpose— Previous work that predated the availability of the safer stent-retriever devices has suggested that general anesthesia (GA) may have a negative impact on outcomes in patients with acute ischemic stroke undergoing endovascular therapy. Methods— We reviewed demographic, clinical, procedural (GA versus local anesthesia [LA], etc), and site-adjudicated angiographic and clinical outcomes data from consecutive patients treated with the Solitaire FR device in the investigator-initiated North American SOLITAIRE Stent-Retriever Acute Stroke (NASA) Registry. The primary outcomes were 90-day modified Rankin Scale, mortality, and symptomatic intracranial hemorrhage. Results— A total of 281 patients from 18 centers were enrolled. GA was used in 69.8% (196/281) of patients. Baseline demographic and procedural factors were comparable between the LA and GA groups, except the former demonstrated longer time-to-groin puncture (395.4±254 versus 337.4±208 min; P=0.04), lower National Institutes of Health Stroke Scale (NIHSS; 16.2±5.8 versus 18.8±6.9; P=0.002), lower balloon-guide catheter usage (22.4% versus 49.2%; P=0.0001), and longer fluoroscopy times (39.5±33 versus 28±22.8 min; P=0.008). Recanalization (thrombolysis in cerebral infarction ≥2b; 72.94% versus 73.6%; P=0.9) and rate of symptomatic intracranial hemorrhage (7.1% versus 11.2%; P=0.4) were similar but modified Rankin Scale ⩽2 was achieved in more LA patients, 52.6% versus 35.6% (odds ratio, 1.4 [1.1–1.8]; P=0.01). In multivariate analysis, hypertension, NIHSS, unsuccessful revascularization, and GA use (odds ratio, 3.3 [1.6–7.1]; P=0.001) were associated with death. When only anterior circulation and elective GA patients were included, there was a persistent difference in good outcomes in favor of LA patients (50.7% versus 35.5%; odds ratio, 1.3 [1.01–1.6]; P=0.04). Conclusions— The NASA Registry has demonstrated that clinical outcomes and survival are significantly better in patients treated with LA, without increased symptomatic intracranial hemorrhage risk. Future trials should prospectively evaluate the effect of GA on outcomes.


Neurology | 2004

Computed tomographic angiography for diagnosis of brain death

Adnan I. Qureshi; Jawad F. Kirmani; Andrew Xavier; Amir M. Siddiqui

The authors report two patients with suspected brain death who required confirmatory tests other than clinical examination because of prolonged barbiturate administration for intracranial hypertension. Absence of intracranial blood flow was documented on CT angiography and confirmed by CT perfusion images. Cerebral angiography confirmed the findings consistent with brain death. CT angiography with CT perfusion may represent a rapid noninvasive method for diagnosis of brain death.


Journal of NeuroInterventional Surgery | 2016

Predictors of poor outcome despite recanalization: a multiple regression analysis of the NASA registry

Italo Linfante; Amy Starosciak; Gail Walker; Guilherme Dabus; Alicia C. Castonguay; Rishi Gupta; Chung Huan J Sun; Coleman O. Martin; William E. Holloway; Nils Mueller-Kronast; Joey D. English; Tim W. Malisch; Franklin A. Marden; Hormozd Bozorgchami; Andrew Xavier; A Rai; Michael T. Froehler; Aamir Badruddin; Thanh N. Nguyen; M. Asif Taqi; Michael G. Abraham; Vallabh Janardhan; Hashem Shaltoni; Roberta Novakovic; Albert J. Yoo; Alex Abou-Chebl; Peng R. Chen; Gavin W. Britz; Ritesh Kaushal; Ashish Nanda

Background Mechanical thrombectomy with stent-retrievers results in higher recanalization rates compared with previous devices. Despite successful recanalization rates (Thrombolysis in Cerebral Infarction (TICI) score ≥2b) of 70–83%, good outcomes by 90-day modified Rankin Scale (mRS) score ≤2 are achieved in only 40–55% of patients. We evaluated predictors of poor outcomes (mRS >2) despite successful recanalization (TICI ≥2b) in the North American Solitaire Stent Retriever Acute Stroke (NASA) registry. Methods Logistic regression was used to evaluate baseline characteristics and recanalization outcomes for association with 90-day mRS score of 0–2 (good outcome) vs 3–6 (poor outcome). Univariate tests were carried out for all factors. A multivariable model was developed based on backwards selection from the factors with at least marginal significance (p≤0.10) on univariate analysis with the retention criterion set at p≤0.05. The model was refit to minimize the number of cases excluded because of missing covariate values; the c-statistic was a measure of predictive power. Results Of 354 patients, 256 (72.3%) were recanalized successfully. Based on 234 recanalized patients evaluated for 90-day mRS score, 116 (49.6%) had poor outcomes. Univariate analysis identified an increased risk of poor outcome for age ≥80 years, occlusion site of internal carotid artery (ICA)/basilar artery, National Institute of Health Stroke Scale (NIHSS) score ≥18, history of diabetes mellitus, TICI 2b, use of rescue therapy, not using a balloon-guided catheter or intravenous tissue plasminogen activator (IV t-PA), and >30 min to recanalization (p≤0.05). In multivariable analysis, age ≥80 years, occlusion site ICA/basilar, initial NIHSS score ≥18, diabetes, absence of IV t-PA, ≥3 passes, and use of rescue therapy were significant independent predictors of poor 90-day outcome in a model with good predictive power (c-index=0.80). Conclusions Age, occlusion site, high NIHSS, diabetes, no IV t-PA, ≥3 passes, and use of rescue therapy are associated with poor 90-day outcome despite successful recanalization.


Southern Medical Journal | 2003

Neuroimaging of stroke: a review.

Andrew Xavier; Adnan I. Qureshi; Jawad F. Kirmani; Abutaher M. Yahia; Rohit Bakshi

Advances in neuroimaging technology during the past 30 years have resulted in a virtual explosion in the amount of pathologic information that can be obtained in the clinical stroke setting. This neuroimaging revolution has led to a much better understanding of cerebrovascular and tissue pathology, creating a wide array of opportunities for acute treatment and secondary prevention. Advances include early and accurate detection of ischemic and infarcted tissue and the ability to reveal hypoperfused tissue at risk. Clinicians are increasingly able to noninvasively detect embolic and atherothrombotic intravascular lesions. Vascular lesions associated with stroke can be characterized through endovascular neuroimaging techniques and repaired by various means. In this article, we provide an overview and update on the various techniques used in the neuroimaging of stroke and intracranial hemorrhage, including computed tomography, magnetic resonance imaging, ultrasound, and catheter angiography. We outline the specific role of each modality in clinical practice.


Journal of Neuroimaging | 2004

Qureshi grading scheme for angiographic occlusions strongly correlates with the initial severity and in-hospital outcome of acute ischemic stroke.

Yousef Mohammad; Andrew Xavier; Greg Christoforidis; Eric C. Bourekas; Andrew Slivka

Background. The thrombolysis in myocardial infarction (TIMI) grading scheme and other classification systems have limitations in evaluating patients with ischemic stroke because they do not account for occlusion location or collateral circulation. The Qureshi grading scheme has been recently proposed to evaluate the severity of arterial occlusion in acute ischemic stroke because of limitations in existing grading systems. Methods. The Qureshi grading scheme assigns a score from 0 to 5 on the basis of occlusion site and collateral supply. The authors determined the relationship between initial severity of stroke and outcome at discharge measured by the National Institutes of Health Stroke Scale (NIHSS) and the Qureshi grading scale assessed from initial angiography (by a neuroradiologist blinded to the clinical examination) in 57 patients who underwent intra arterial therapy for acute ischemic stroke within 6 hours of symptom onset. Results. A strong association was observed between the initial severity of neurological deficits and Qureshi scheme on angiography (F ratio = 2.6, P = .03). The initial NIHSS for grade 1 was 11 ± 4 and progressively increased to 23 ± 6 for grade 5. In the multivariate analysis, initial NIHSS was significantly associated with Qureshi scheme on angiography (R2 = 358, P = .03). The mean discharge NIHSS was 12 ± 10 (range, 0–40). There was also a direct relationship between the Qureshi scheme and discharge NIHSS (F ratio = 2.8, P = .02).Conclusion. The Qureshi grading scheme can be effectively used to determine the severity of ischemic stroke (brain at risk) from the initial angiography.


Stroke | 2014

Influence of Age on Clinical and Revascularization Outcomes in the North American Solitaire Stent-Retriever Acute Stroke Registry

Alicia C. Castonguay; Osama O. Zaidat; Roberta Novakovic; Thanh N. Nguyen; M. Asif Taqi; Rishi Gupta; Chung Huan J Sun; Coleman O. Martin; William E. Holloway; Nils Mueller-Kronast; Joey E. English; Italo Linfante; Guilherme Dabus; Tim W. Malisch; Franklin A. Marden; Hormozd Bozorgchami; Andrew Xavier; A Rai; Michael T. Froehler; Aamir Badruddin; Michael G. Abraham; Vallabh Janardhan; Hashem Shaltoni; Albert J. Yoo; Alex Abou-Chebl; Peng R. Chen; Gavin W. Britz; Ritesh Kaushal; Ashish Nanda; Mohammad A. Issa

Background and Purpose— The Solitaire With the Intention for Thrombectomy (SWIFT) and thrombectomy revascularization of large vessel occlusions in acute ischemic stroke (TREVO 2) trial results demonstrated improved recanalization rates with mechanical thrombectomy; however, outcomes in the elderly population remain poorly understood. Here, we report the effect of age on clinical and angiographic outcome within the North American Solitaire-FR Stent-Retriever Acute Stroke (NASA) Registry. Methods— The NASA Registry recruited sites to submit data on consecutive patients treated with Solitaire-FR. Influence of age on clinical and angiographic outcomes was assessed by dichotomizing the cohort into ⩽80 and >80 years of age. Results— Three hundred fifty-four patients underwent treatment in 24 centers; 276 patients were ⩽80 years and 78 were >80 years of age. Mean age in the ⩽80 and >80 cohorts was 62.2±13.2 and 85.2±3.8 years, respectively. Of patients >80 years, 27.3% had a 90-day modified Rankin Score ⩽2 versus 45.4% ⩽80 years (P=0.02). Mortality was 43.9% and 27.3% in the >80 and ⩽80 years cohorts, respectively (P=0.01). There was no significant difference in time to revascularization, revascularization success, or symptomatic intracranial hemorrhage between the groups. Multivariate analysis showed age >80 years as an independent predictor of poor clinical outcome and mortality. Within the >80 cohort, National Institutes of Health Stroke Scale (NIHSS), revascularization rate, rescue therapy use, and symptomatic intracranial hemorrhage were independent predictors of mortality. Conclusion— Greater than 80 years of age is predictive of poor clinical outcome and increased mortality compared with younger patients in the NASA registry. However, intravenous tissue-type plasminogen activator use, lower NIHSS, and shorter revascularization time are associated with better outcomes. Further studies are needed to understand the endovascular therapy role in this cohort compared with medical therapy.


Neurology | 2012

Developing practice recommendations for endovascular revascularization for acute ischemic stroke

Marc A. Lazzaro; Roberta Novakovic; Andrei V. Alexandrov; Ziad Darkhabani; Randall C. Edgell; Joey D. English; Donald Frei; Dara G. Jamieson; Vallabh Janardhan; Nazli Janjua; Rashid M. Janjua; Irene Katzan; Pooja Khatri; Jawad F. Kirmani; David S. Liebeskind; Italo Linfante; Thanh N. Nguyen; Jeffrey L. Saver; Lori Shutter; Andrew Xavier; Dileep R. Yavagal; Osama O. Zaidat

Guidelines have been established for the management of acute ischemic stroke; however, specific recommendations for endovascular revascularization therapy are lacking. Burgeoning investigation of endovascular revascularization therapies for acute ischemic stroke, rapid device development, and a diverse training background of the providers performing the procedures underscore the need for practice recommendations. This review provides a concise summary of the Society of Vascular and Interventional Neurology endovascular acute ischemic stroke roundtable meeting. This document was developed to review current clinical efficacy of pharmacologic and mechanical revascularization therapy, selection criteria, periprocedure management, and endovascular time metrics and to highlight current practice patterns. It therefore provides an outline for the future development of multisociety guidelines and recommendations to improve patient selection, procedural management, and organizational strategies for revascularization therapies in acute ischemic stroke.


Neurosurgical Focus | 2008

Modern psychosurgery before Egas Moniz: a tribute to Gottlieb Burckhardt

Sunil Manjila; Setti S. Rengachary; Andrew Xavier; Brandon Parker; Murali Guthikonda

The history of modern psychosurgery has been written in several ways, weaving around many pioneers in the field during the 19th century. Often neglected in this history is Gottlieb Burckhardt (1836-1907), who performed the first psychosurgical procedures as early as 1888, several decades before the work of Egas Moniz (1874-1955). The unconventional and original case series of Burckhardt, who claimed success in 50% of patients (3 of 6), had met with overt criticism from his contemporary medical colleagues. The authors describe 2 illustrative cases of cortical extirpation performed by Burckhardt and review his pioneering case series for surgical outcome, despite the ambiguity in postoperative evaluation criteria. Although Burckhardt discontinued the project after publication of his surgical results in 1891, neurosurgeons around the world continued to investigate psychosurgery and revitalized his ideas in 1910; psychosurgery subsequently developed into a full-fledged neurosurgical specialty.

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Italo Linfante

Baptist Memorial Hospital-Memphis

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Vallabh Janardhan

State University of New York System

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Aamir Badruddin

Medical College of Wisconsin

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Alicia C. Castonguay

Medical College of Wisconsin

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Hashem Shaltoni

University of Texas Health Science Center at Houston

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A Rai

West Virginia University

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