Alexandros L. Georgiadis

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.

Intra-Arterial Recanalization Techniques for Patients 80 Years or Older with Acute Ischemic Stroke: Pooled Analysis from 4 Prospective Studies

BACKGROUND AND PURPOSE: Previous studies have demonstrated limited benefit with endovascular procedures such as stent placement in octogenarians. We evaluated the safety and effectiveness of intra-arterial recanalization techniques to treat ischemic stroke in patients 80 years or older presenting within 6 hours of symptom onset. MATERIALS AND METHODS: We pooled the data from 4 prospective studies by evaluating intra-arterial recanalization techniques for treatment of ischemic stroke. Clinical and radiologic evaluations were performed before treatment and at 24 hours, 7 to 10 days, and 1 to 3 months after treatment. We performed multivariate analyses to evaluate the effect of ages 80 years and older on angiographic recanalization, favorable outcome (modified Rankin scale of 0–2), and mortality rate at 1 to 3 months. RESULTS: A total of 101 patients were treated in the 4 protocols. Of these, 24 were 80 years or older. There was no significant difference between the 2 age groups in sex, initial stroke severity, time to treatment, site of vascular occlusion, and rate of symptomatic and asymptomatic intracranial hemorrhage (ICH). In logistic regression analysis, age 80 years or older was associated with a lower likelihood of a favorable outcome (odds ratio [OR], 0.40; 95% confidence interval [CI], 0.13–1.2; P = .11) and recanalization (OR, 0.36; 95% CI, 0.12–1.1; P = .07) and with higher mortality rate (OR, 3.17; 95% CI, 1.05–9.55; P = .04) after adjusting for study protocol. After adjusting for recanalization in addition to study protocol, the older age group still had a lower likelihood of favorable outcomes (OR, 0.34; 95% CI, 0.1–1.1; P = .07) and higher mortality rates (OR, 3.62; 95% CI, 1.15–11.36; P = .027). CONCLUSIONS: Our study demonstrates that patients 80 years and older are at higher risk for poor outcome at 1 to 3 months following intra-arterial recanalization techniques. This relationship is independent of recanalization rate and symptomatic ICH supporting the role of other mechanisms.

Endovascular Interventions following Intravenous Thrombolysis May Improve Survival and Recovery in Patients with Acute Ischemic Stroke: A Case-Control Study

BACKGROUND AND PURPOSE: Since the introduction of recombinant tissue plasminogen activator (rtPA) into clinical practice in the mid 1990s, no adjunctive treatment has further improved clinical outcomes in patients with ischemic stroke. The safety, feasibility, and efficacy of combining intravenous (IV) rtPA with endovascular interventions has been described; however, no direct comparative study has yet established whether endovascular interventions after IV rtPA are superior to IV rtPA alone. A retrospective case-control study was designed to address this issue. MATERIALS AND METHODS: Between 2003 and 2006, 33 consecutive patients with acute ischemic stroke and National Institutes of Health Stroke Scale (NIHSS) scores ≥10 were treated with IV rtPA in combination with endovascular interventions (IV plus intervention) at a tertiary care facility. Outcomes were compared with a control cohort of 30 consecutive patients treated with IV rtPA (IV only) at a comparable facility where endovascular interventions were not available. RESULTS: Baseline parameters were similar between the 2 groups. We found that the IV-plus-intervention group experienced significantly lower mortality at 90 days (12.1% versus 40.0%, P = .019) with a significantly greater improvement in NIHSS scores by the time of discharge or follow-up (P = .025). In the IV-plus-intervention group, patients with admission NIHSS scores between 10 and 15 and patients ≤80 years of age showed the greatest improvement, with a significant change of the NIHSS scores from admission (P = .00015 and P = .013, respectively). CONCLUSIONS: In this small case-control study of patients with acute ischemic stroke and admission NIHSS scores ≥10, there was a suggestion of incremental clinical benefit among patients receiving endovascular interventions following standard administration of IV rtPA.

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.

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.

Premorbid use of statins is associated with higher recanalization rates in patients with acute ischemic stroke undergoing endovascular treatment.

Statins have been shown to have lipid‐independent (pleiotropic) effects that may be beneficial in the management of vascular disease. We evaluated the effect of premorbid statin use on recanalization in patients with acute ischemic stroke undergoing endovascular treatment.

Intravenous recombinant tissue plasminogen activator administered after 3 h following onset of ischaemic stroke: a metaanalysis*

Objective To assess the efficacy of intravenous recombinant tissue plasminogen activator administered after 3 h following onset of ischaemic stroke. Background Some recent data indicate that treatment with intravenous recombinant tissue plasminogen activator may be beneficial even when administered to ischaemic stroke patients beyond 3 h from symptom onset. Methods We searched the medical literature using the MEDLINE, BIOSIS, and Cochrane databases for pertinent publications from 1966 to 2008 using the keywords ‘alteplase’, ‘tissue plasminogen activator’, and ‘stroke’. Among the retrieved publications, we selected randomised controlled trials that administered recombinant tissue plasminogen activator during 3–6 h after symptom onset in patients with acute ischaemic stroke. We evaluated the effect of intravenous recombinant tissue plasminogen activator (compared with placebo) on the rate of good functional outcome (determined by modified Rankin Scale of 0–1) and mortality at three-months. A subset analysis was performed according to time of administration of intravenous recombinant tissue plasminogen activator (3–4·5 and 4·5–6 h). Odds ratios of individual trials were pooled using a random effects model. Results We analysed four randomised trials totaling 2104 patients (1053 control and 1051 recombinant tissue plasminogen activator-treated patients). Patients that received intravenous recombinant tissue plasminogen activator at 3–6 h following onset of symptoms had a significantly higher rate of favourable neurological outcome over the patients that received placebo (odds ratio 1·24, 95% confidence intervals 1·04–1·47, P=0·02). Treatment within the 3–4·5 time window was significantly associated with higher rate of favourable neurological outcome (OR 1·27, 95% confidence interval 1·01–1·60), but not for the 4·5–6 time window (OR 1·10, 95% confidence interval 0·75–1·51). There was no difference in mortality between patients that received intravenous recombinant tissue plasminogen activator than the patients that received pharmacologic placebo (OR 1·14, 95% confidence interval 0·76–1·70). Conclusions Treatment with intravenous recombinant tissue plasminogen activator from 3–4·5 h following symptom onset is associated with an increased rate of favourable outcome at 90-days in this analysis. Treatment with intravenous recombinant tissue plasminogen activator beyond 4·5 h did not show a benefit; however, improved patient selection is needed for future studies.

Predictors and Timing of Neurological Complications Following Intracranial Angioplasty and/or Stent Placement

BACKGROUND:Transient or permanent neurological complications can occur in the periprocedural period following intracranial angioplasty and/or stent placement. Which patients are at risk and the time period for maximum vulnerability among those who undergo intracranial angioplasty and/or stent placement have not been formally studied. OBJECTIVE:To assess the predictors and timing of neurological complications following intracranial angioplasty and/or stent placement in the periprocedural period in a consecutive series of patients. METHODS:We reviewed medical records and angiograms of consecutive patients treated with intracranial angioplasty and/or stent placement in 3 academic institutions. We evaluated the effect of demographic, clinical, intraprocedural, and angiographic risk factors on subsequent development of periprocedural neurological complications. Periprocedural neurological complications were defined as new or worsening transient or permanent neurological complications that occurred during or within 1 month of the procedure. We also recorded the timing and nature of neurological complications in the periprocedural period. RESULTS:A total of 92 patients were included in the study (mean age ± standard deviation: 59 ± 14 years; 59 were men). The overall rate of in-hospital neurological complications was 9.8% (9 of 92 patients). Eight out of 9 neurological complications occurred either during the procedure or within 6 hours thereafter. Presence of diabetes mellitus (P = .003) and use of balloon-expandable stent (P = .09) were associated with periprocedural neurological complications. The degree of pre- and post-procedure stenosis, morphological appearance, and length of lesion were unrelated to periprocedural complications. CONCLUSION:Patients with diabetes mellitus and those treated with balloon expandable stents are at high risk for periprocedural neurological complications. The first 6 hours following intracranial angioplasty and stent placement represent the period of highest risk.

Assessment of platelet inhibition by point-of-care testing in neuroendovascular procedures.

SUMMARY: Antiplatelet agents are an important component of the preventive strategies currently used in clinical practice to minimize the risk of thromboembolic events during and after endovascular procedures. Because of the variability in the response to antiplatelet agents, measuring the degree of platelet inhibition may help identify and properly treat poor responders. POC testing is defined as diagnostic testing at or near the site of patient care. Knowledge of the specifics of these devices among practicing neurointerventionalists is relatively limited. In this article, the different POC devices available are presented, and their clinical utility in relation to endovascular procedures is discussed.

Textbook of interventional neurology

Preface 1. History of interventional neurology Adnan I. Qureshi 2. Diagnostic cerebral angiography Adnan I. Qureshi and Ameer E. Hassan 3. Overview of pharmacological agents Ameer E. Hassan, Steve M. Cordina, Haitham H. Hussein, Deepak L. Bhatt and Adnan I. Qureshi 4. Periprocedural care Alexandros L. Georgiadis and Mustapha A. Ezzeddine 5. Acute ischemic stroke Alexandros L. Georgiadis, Georgios Tsivgoulis, Andrei Alexandrov, Adnan I. Qureshi and Jose I. Suarez 6. Extracranial carotid artery disease Adnan I. Qureshi and L. Nelson Hopkins 7. Extracranial vertebral artery disease Robert A. Taylor, Zeeshan M. Memon and Adnan I. Qureshi 8. Intracranial stenosis Farhan Siddiq, Adnan I. Qureshi and Camilo R. Gomez 9. Arterial dissection YihLin Nien, Jose Rafael Romero, Thanh N. Nguyen and Adnan I. Qureshi 10. Traumatic vascular injury Jefferson T. Miley, Qaisar A. Shah and Adnan I. Qureshi 11. Intracranial aneurysms Alexandros L. Georgiadis, Matthew D. Ford, David A. Steinman, Nauman Tariq and Adnan I. Qureshi 12. Cerebral vasospasm Adnan I. Qureshi, Mushtaq Qureshi, Jefferson T. Miley, Nauman Tariq and Giuseppe Lanzino 13. Intracranial arterio-venous malformations Dorothea Strozyk, Carlos E. Baccin, Johnny C. Pryor and Raul G. Nogueira 14. Dural arterio-venous fistulas Thanh N. Nguyen, Jean Raymond, Alexander M. Norbash and Daniel Roy 15. Cerebral venous thrombosis Amit Singla and Randall C. Edgell 16. Intracranial and head and neck tumors: embolization and chemotherapy Adnan I. Qureshi, Nauman Tariq, Rabia Qaiser, Herbert B. Newton and Stephen J. Haines 17. Diagnostic and provocative testing Haralabos Zacharatos, Ameer E. Hassan, M. Fareed K. Suri and Adnan I. Qureshi 18. Spinal vascular and neoplastic lesions Osman Kozak and Edgard Pereira 19. Central retinal artery occlusion Alberto Maud, Zeeshan M. Memon and M. Fareed K. Suri 20. Epistaxis Alexandros L. Georgiadis, Steve Cordina and Adnan I. Qureshi 21. Vertebroplasty and kyphoplasty Stanley H. Kim, Anant I. Patel, Nancy Gruell, Kirk Conrad and Young J. Yu 22. Clinical trials for neuro-endovascular procedures: fundamentals of design and interpretation Haitham H. Hussein and Adnan I. Qureshi 23. Qualification requirements for performing endovascular procedures Adnan I. Qureshi, Alex Abou-Chebl and Tudor G. Jovin Index.