Sundeep Mangla

Urgent endovascular revascularization for symptomatic intracranial atherosclerotic stenosis

Background: Endovascular revascularization for intracranial atherosclerotic stenoses is being increasingly performed at major medical centers and has been reported to be technically feasible and safe. The authors report their experience with patients who underwent such a procedure for impending stroke and neurologic instability. Method: All 18 patients (21 intracranial lesions) treated between 1997 and 2002 at the authors’ institution with endovascular revascularization were retrospectively reviewed. Each patient had failed maximal medical therapy and was thought to be at high risk for an imminent stroke. Results: Endovascular revascularization was performed on eight distal internal carotid artery lesions, six middle cerebral artery lesions, four intracranial vertebral artery lesions, and three basilar artery lesions. Recanalization was complete in 5 arteries (Thrombolysis in Myocardial Infarction [TIMI] Grade III), partial in 14 arteries (TIMI Grade II), and complete occlusion (TIMI 0) developed in 1 artery. In a patient with a tight basilar stenosis, no angioplasty could be performed because of the inability to cross the stenosis with the guidewire. Major periprocedural complications occurred in 9 (50%) patients: intracranial hemorrhage in 3 (17%), disabling ischemic stroke in 2 (11%), and major extracranial hemorrhage in 4 (22%). Three patients died: one from intracerebral hemorrhage and two from cardiorespiratory failure. Conclusions: Endovascular revascularization of intracranial vessels is technically feasible and may be performed successfully. However, periprocedural complication and fatality rates in neurologically unstable patients are high. The results suggest that patient selection, procedure timing, and periprocedural medical management are critical factors to reduce periprocedural morbidity and mortality.

Endovascular Recanalization Therapy in Acute Ischemic Stroke

BACKGROUND AND PURPOSE To assess the outcome in acute ischemic stroke patients not eligible for systemic thrombolysis (outside the 3-hour time window, after surgery, or on anticoagulant) undergoing endovascular recanalization therapy (ERT) at the Columbia University Medical Center (CUMC) and to determine US nationwide usage and outcome of ERT in acute ischemic stroke. METHODS Patients treated at CUMC from 2001 to 2004 and the Nationwide Inpatient Sample (NIS) comprising 20% of all admissions in the United States from 1999 to 2002 were analyzed retrospectively. RESULTS Thirty-one patients underwent ERT. Mean age was 68+/-14 years, 68% were female, and 45% nonwhite (occlusion sites: internal carotid artery 29%; middle cerebral artery 39%; posterior circulation 32%). Pharmacological or mechanical ERT was initiated beyond 3 hours after symptom onset (median time 4.4 hours) in 61%, 29% had surgery, and 39% were on anticoagulant medication. At discharge, 32% had modified Rankin Scale scores of 0 to 2 (52% discharged home or to rehabilitation facilities); overall mortality was 29%, of which 19% were fatal intracerebral hemorrhages. From the NIS cohort, 477 patients (0.17% of all strokes and 14% of all thrombolysis cases) underwent ERT. Fifteen percent died, and approximately 50% were discharged home or to rehabilitation facilities. Intracerebral hemorrhage occurred in 6%. Fewer good outcomes of the CUMC cohort may be explained by more unfavorable premorbid patient characteristics compared with the NIS cohort. CONCLUSIONS Despite significant variability in patient characteristics and treatment methods among 2 sources of data analyzed, ERT in stroke patients not eligible for intravenous thrombolysis appears to be a relatively safe and effective treatment alternative that is being used increasingly nationwide.

Conducting Stroke Research With an Exception From the Requirement for Informed Consent

Background— Obtaining viable informed consent from stroke patients for participation in clinical trials of acute stroke therapies is often problematic because of patients’ neurological deficits. Furthermore, obtaining permission from surrogates is often not possible or not legally permissible. Summary of Review— In 1996 the Food and Drug Administration and Department of Health and Human Services published regulations that allow investigators to conduct emergency research without patient consent under a narrowly defined set of circumstances. We review requirements of these regulations, paying particular attention to how they may be applied in a clinical trial of an acute stroke therapy. Conclusions— Acute stroke researchers should consider conducting clinical trials with an exception from the informed consent requirement permitted by this law.

Major Neurologic Improvement following Endovascular Recanalization Therapy for Acute Ischemic Stroke

Background: We aimed to identify the rate of major neurologic improvement (MNI) at 24 h following endovascular recanalization therapy (ERT) for acute ischemic stroke and its association with short-term outcome. Methods: We retrospectively reviewed consecutive acute ischemic stroke patients presenting to our institution over 4 years and undergoing ERT. Angiograms were independently reviewed. Data on demographics, medical history, initial NIHSS score, 24-hour NIHSS score, site of acute vascular lesion, pre- and posttreatment Thrombolysis in Myocardial Infarction scores, symptomatic intracerebral hemorrhage (within 36 h of intervention that was associated with a 4-point decline in NIHSS score) and discharge disposition were collected. We used logistic regression analysis to identify predictors of MNI (defined as ≥8-point improvement in NIHSS or a score of 0–1 at 24 h) and favorable discharge status (defined as home or acute rehabilitation). Results: Sixty-eight patients were included (median age = 71 years, 60% women, median NIHSS score = 19.5, anterior circulation = 75%). The modes of ERT were pharmacologic only (28%), mechanical only (35%) and multimodal therapy (37%). Thrombolysis in Myocardial Infarction 2 or 3 recanalization was achieved in 64.7% (mechanical only 46%, pharmacologic only 63% and multimodal 84%). The outcomes were: symptomatic intracerebral hemorrhage (11.8%), MNI (26.5%) and favorable discharge (41.2%). Age (OR = 0.93, p = 0.003) and cardioembolic stroke subtype (OR = 6.0, p = 0.018) were independent predictors of MNI. MNI was a strong predictor of favorable discharge status (OR = 46.4, p < 0.001). Conclusions: Despite initial stroke severity, MNI occurred in over one fourth of the patients and independently and strongly predicted favorable discharge outcome.

Histopathological Evaluation of Middle Cerebral Artery After Percutaneous Intracranial Transluminal Angioplasty

BACKGROUND Intracranial atherosclerosis accounts for 8% to 10% of all ischemic strokes, and intracranial angioplasty is increasingly performed to treat stenotic lesions. We report an autopsy case and discuss the effects of intracranial angioplasty for atherosclerotic arteries. CASE DESCRIPTION A 77-year-old patient died 9 days after angioplasty of the left middle cerebral artery as a result of cardiorespiratory failure. The patient was anticoagulated before, during, and after the procedure with heparin, aspirin, and clopidogrel. At the site of angioplasty, the densely fibrotic eccentric plaque was displaced from the adjacent media into the lumen, distorting it and forming elongated projections. No local thrombosis, plaque compression, or inflammation was observed. Additionally, an intramural hemorrhage extended from the site of angioplasty into the stenotic proximal inferior division of the left middle cerebral artery. CONCLUSIONS Histopathological findings after intracranial angioplasty parallel those in other arterial territories. The implications of these pathological findings on the medical and endovascular treatment of intracranial atherosclerosis are discussed.

In nonhuman primates intracarotid adenosine, but not sodium nitroprusside, increases cerebral blood flow

Intracarotid infusion of short-acting vasodilators, such as adenosine and nitroprusside, in doses that lack significant systemic side effects, may permit controlled manipulation of cerebrovascular resistance. In this experiment we assessed changes in cerebral blood flow (CBF) after intracarotid infusion of nitroprusside and adenosine. The study was conducted on six adult baboons under isoflurane anesthesia and controlled ventilation. Intracarotid drug infusion protocol avoided hypotension during nitroprusside infusion and tested for autoregulatory vasoconstriction. CBF (intraarterial 133Xe technique) was measured four times during infusions of 1) intracarotid saline, 2) IV phenylephrine (0.2 &mgr;g · kg−1 · min−1) aimed to increase mean arterial pressure by 10–15 mm Hg, 3) IV phenylephrine and intracarotid nitroprusside (0.5 &mgr;g · kg−1 · min−1), and 4) intracarotid adenosine (1 mg/min). IV phenylephrine increased mean arterial pressure (69 ± 8 to 91 ± 9 mm Hg, P < 0.0001, n = 6), and concurrent infusion of intracarotid nitroprusside reversed this effect. However, compared with baseline, CBF did not change with IV phenylephrine or with concurrent infusion of IV phenylephrine and intracarotid nitroprusside. Intracarotid adenosine profoundly increased CBF (from 29 ± 8 to 75 ± 32 mL · 100 g−1 · min−1;P < 0.0001). In nonhuman primates, intracarotid adenosine increases CBF in doses that lack significant systemic side effects, whereas intracarotid nitroprusside has no effect. Intracarotid adenosine may be useful for manipulating cerebrovascular resistance and augmenting CBF during cerebral ischemia.

Novel model of direct and indirect cost–benefit analysis of mechanical embolectomy over IV tPA for large vessel occlusions: a real-world dollar analysis based on improvements in mRS

Background Ischemic strokes result in significant healthcare expenditures (direct costs) and loss of quality-adjusted life years (QALYs) (indirect costs). Interventional therapy has demonstrated improved functional outcomes in patients with large vessel occlusions (LVOs), which are likely to reduce the economic burden of strokes. Objective To develop a novel real-world dollar model to assess the direct and indirect cost–benefit of mechanical embolectomy compared with medical treatment with intravenous tissue plasminogen activator (IV tPA) based on shifts in modified Rankin scores (mRS). Method A cost model was developed including multiple parameters to account for both direct and indirect stroke costs. These were adjusted based upon functional outcome (mRS). The model compared IV tPA with mechanical embolectomy to assess the costs and benefits of both therapies. Direct stroke-related costs included hospitalization, inpatient and outpatient rehabilitation, home care, skilled nursing facilities, and long-term care facility costs. Indirect costs included years of life expectancy lost and lost QALYs. Values for the model cost parameters were derived from numerous resources and functional outcomes were derived from the MR CLEAN study as a reflective sample of LVOs. Direct and indirect costs and benefits for the two treatments were assessed using Microsoft Excel 2013. Results This cost–benefit model found a cost–benefit of mechanical embolectomy over IV tPA of

External carotid arterial injury

163 624.27 per patient and the cost benefit for 50 000 patients on an annual basis is

Clinical Reasoning: A rare cause of subarachnoid hemorrhage

8 181 213 653.77. Conclusions If applied widely within the USA, mechanical embolectomy will significantly reduce the direct and indirect financial burden of stroke (

System for autonomous robotic navigation

8 billion/50 000 patients).