Muhammad S Hussain

Higher volume endovascular stroke centers have faster times to treatment, higher reperfusion rates and higher rates of good clinical outcomes

Background and purpose Technological advances have helped to improve the efficiency of treating patients with large vessel occlusion in acute ischemic stroke. Unfortunately, the sequence of events prior to reperfusion may lead to significant treatment delays. This study sought to determine if high-volume (HV) centers were efficient at delivery of endovascular treatment approaches. Methods A retrospective review was performed of nine centers to assess a series of time points from obtaining a CT scan to the end of the endovascular procedure. Demographic, radiographic and angiographic variables were assessed by multivariate analysis to determine if HV centers were more efficient at delivery of care. Results A total of 442 consecutive patients of mean age 66±14 years and median NIH Stroke Scale score of 18 were studied. HV centers were more likely to treat patients after intravenous administration of tissue plasminogen activator and those transferred from outside hospitals. After adjusting for appropriate variables, HV centers had significantly lower times from CT acquisition to groin puncture (OR 0.991, 95% CI 0.989 to 0.997, p=0.001) and total procedure times (OR 0.991, 95% CI 0.986 to 0.996, p=0.001). Additionally, patients treated at HV centers were more likely to have a good clinical outcome (OR 1.86, 95% CI 1.11 to 3.10, p<0.018) and successful reperfusion (OR 1.82, 95% CI 1.16 to 2.86, p<0.008). Conclusions Significant delays occur in treating patients with endovascular therapy in acute ischemic stroke, offering opportunities for improvements in systems of care. Ongoing prospective clinical trials can help to assess if HV centers are achieving better clinical outcomes and higher reperfusion rates.

Delayed Migration of a Self-Expanding Intracranial Microstent

SUMMARY: A 43-year-old patient with a basilar apex aneurysm had a 4.5-mm × 14-mm Enterprise stent placed from the midbasilar artery to the left P1 segment of the posterior cerebral artery. The patient experienced vertigo 4 months after stent placement and 1 week after stopping clopidogrel. At 5 months postembolization, angiography showed stent migration into the proximal basilar artery. This is the first described case of the spontaneous delayed migration of a self-expanding intracranial microstent.

Advanced modality imaging evaluation in acute ischemic stroke may lead to delayed endovascular reperfusion therapy without improvement in clinical outcomes

Purpose Advanced neuroimaging techniques may improve patient selection for endovascular stroke treatment but may also delay time to reperfusion. We studied the effect of advanced modality imaging with CT perfusion (CTP) or MRI compared with non-contrast CT (NCT) in a multicenter cohort. Materials and methods This is a retrospective study of 10 stroke centers who select patients for endovascular treatment using institutional protocols. Approval was obtained from each institutions review board as only de-identified information was used. We collected demographic and radiographic data, selected time intervals, and outcome data. ANOVA was used to compare the groups (NCT vs CTP vs MRI). Binary logistic regression analysis was performed to determine factors associated with a good clinical outcome. Results 556 patients were analyzed. Mean age was 66±15 years and median National Institutes of Health Stroke Scale score was 18 (IQR 14–22). NCT was used in 286 (51%) patients, CTP in 190 (34%) patients, and MRI in 80 (14%) patients. NCT patients had significantly lower median times to groin puncture (61 min, IQR (40–117)) compared with CTP (114 min, IQR (81–152)) or MRI (124 min, IQR (87–165)). There were no differences in clinical outcomes, hemorrhage rates, or final infarct volumes among the groups. Conclusions The current retrospective study shows that multimodal imaging may be associated with delays in treatment without reducing hemorrhage rates or improving clinical outcomes. This exploratory analysis suggests that prospective randomised studies are warranted to support the hypothesis that advanced modality imaging is superior to NCT in improving clinical outcomes.

The changing face of neurosyphilis

The incidence of syphilis has increased over the past decade, particularly among HIV-positive patients, and the presenting clinical features have changed since the beginning of the HIV epidemic. The clinical manifestations of neurosyphilis are protean, and include acute stroke. In patients with HIV, the diagnosis and treatment of neurosyphilis is challenging. We review the clinical presentation, pathophysiology, and treatment of neurosyphilis, with emphasis on neurosyphilis in the HIV population, and neurosyphilis as a cause of acute stroke.

Should neurointerventional fellowship training be suspended indefinitely

> To bring about destruction by overcrowding, mass starvation, anarchy, the destruction of our most cherished values—there is no need to do anything. We need only do nothing except what comes naturally—and breed. And how easy it is to do nothing. Isaac Asimov The purpose of any training program is to provide a supply of skilled workers to address an unmet demand for their services. With respect to medical training, new physicians are required either to take the place of retiring physicians or to address an unmet demand for patient care. Evolving data strongly suggest that the supply of neurointerventional (NI) physicians is not only sufficient, but has exceeded the present need for services. Despite this, we continue to train new neurointerventionists (NIs) in unprecedented and increasing numbers every year. These new NI physicians are finding it progressively more difficult to secure employment and, once hired, face considerable challenges in building a practice and developing/maintaining their skills. Fellowship training is ingrained into the fabric of our academic practices and currently seems to be perpetuated more by inertia than a dynamic evaluation of the present workforce needs. It is the position of the authors that, if we do not re-evaluate this process, we are potentially doing a tremendous disservice to the people we are training, to patients in need of treatment (and maybe more importantly to those patients with lesions who are not in need of treatment), and finally to ourselves. One of the more difficult aspects of evaluating the NI workforce is obtaining accurate data to characterize the status of current supply and demand—such as the number of practicing NI physicians, the number and growth rate of neuroendovascular cases and the number of new graduates entering the market each year. These statistics must be triangulated using several available sources, the most …

Endovascular therapy for acute ischemic stroke with occlusion of the middle cerebral artery M2 segment

Importance Randomized clinical trials have shown the superiority of endovascular therapy (EVT) compared with best medical management for acute ischemic strokes with large vessel occlusion (LVO) in the anterior circulation. However, of 1287 patients enrolled in 5 trials, 94 with isolated second (M2) segment occlusions were randomized and 51 of these received EVT, thereby limiting evidence for treating isolated M2 segment occlusions as reflected in American Heart Association guidelines. Objective To evaluate EVT safety and effectiveness in M2 occlusions in a cohort of patients with acute ischemic stroke. Design, Setting, and Participants This multicenter retrospective cohort study pooled patients with acute ischemic strokes and LVO isolated to M2 segments from 10 US centers. Patients with acute ischemic strokes and LVO in M2 segments presenting within 8 hours from their last known normal clinical status (LKN) from January 1, 2012, to April 30, 2015, were divided based on their treatment into EVT and medical management groups. Logistic regression was used to compare the 2 groups. Univariate and multivariate analyses evaluated associations with good outcome in the EVT group. Main Outcomes and Measures The primary outcome was the 90-day modified Rankin Scale score (range, 0-6; scores of 0-2 indicate a good outcome); the secondary outcome was symptomatic intracerebral hemorrhage. Results A total of 522 patients (256 men [49%]; 266 women [51%]; mean [SD] age, 68 [14.3] years) were identified, of whom 288 received EVT and 234 received best medical management. Patients in the medical management group were older (median [interquartile range] age, 73 [60-81] vs 68 [56-78] years) and had higher rates of intravenous tissue plasminogen activator treatment (174 [74.4%] vs 172 [59.7%]); otherwise the 2 groups were balanced. The rate of good outcomes was higher for EVT (181 [62.8%]) than for medical management (83 [35.4%]). The EVT group had 3 times the odds of a good outcome as the medical management group (odds ratio [OR], 3.1; 95% CI, 2.1-4.4; P < .001) even after adjustment for age, National Institute of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early Computed Tomographic Score (ASPECTS), intravenous tissue plasminogen activator treatment, and time from LKN to arrival in the emergency department (OR, 3.2; 95% CI, 2-5.2; P < .001). No statistical difference in symptomatic intracerebral hemorrhage was found (5.6% vs 2.1% for the EVT group vs the medical management group; P = .10). The treatment effect did not change after adjusting for center (OR, 3.3; 95% CI, 1.9-5.8; P < .001). Age, NIHSS score, ASPECTS, time from LKN to reperfusion, and successful reperfusion score of at least 2b (range, 0 [no perfusion] to 3 [full perfusion with filling of all distal branches]) were independently associated with good outcome of EVT. A linear association was found between good outcome and time from LKN to reperfusion. Conclusions and Relevance Although a randomized clinical trial is needed to confirm these findings, available data suggest that EVT is reasonable, safe, and effective for LVO of the M2 segment relative to best medical management.

The versatile distal access catheter: The Cleveland clinic experience

BACKGROUND:Vascular access is fundamental to any endovascular intervention. Concentric Medical has developed the Outreach Distal Access Catheter (DAC), which affords stable access at the target vessel modulating the forces at play within the thrombectomy device complex. The DAC is a device with novel access characteristics useful in a host of other types of clinical scenarios. OBJECTIVE:To review our experience with the DAC family of devices, the theory, and method of use. METHODS:A retrospective review of all cases in which the DAC was used during the period 2008 to 2010 was conducted and the cases classified by indication. Catheter-related complications were recorded. The use of the DAC in a variety of settings including intracranial stenting, aneurysm coil embolization, and arteriovenous malformation embolization is described. RESULTS:The DAC was used in 103 procedures performed in 93 patients between August 2008 and February 2010. Indications included acute stroke, treatment of intracranial atherosclerosis, vasospasm therapy, arteriovenous malformation embolization, and aneurysm embolization. In those procedures, 113 catheters were used. No complications directly attributable to DAC use were identified. CONCLUSION:The DAC is useful for gaining access to the cerebral vasculature, especially in patients with significant tortuosity or when re-access of distal vasculature is required multiple times.

Telemedicine in Prehospital Stroke Evaluation and Thrombolysis: Taking Stroke Treatment to the Doorstep

IMPORTANCE Mobile stroke treatment units (MSTUs) with on-site treatment teams that include a vascular neurologist can provide thrombolysis in the prehospital setting faster than treatment in the hospital. These units can be made more resource efficient if the need for an on-site neurologist can be eliminated by relying solely on telemedicine for physician presence. OBJECTIVE To test whether telemedicine is reliable and remote physician presence is adequate for acute stroke treatment using an MSTU. DESIGN, SETTING, AND PARTICIPANTS Prospective observational study conducted between July 18 and November 1, 2014. The dates of the study analysis were November 1, 2014, to March 30, 2015. The setting was a community-based study assessing telemedicine success of the MSTU in Cleveland, Ohio. Participants were the first 100 residents of Cleveland who had an acute onset of stroke-like symptoms between 8 am and 8 pm and were evaluated by the MSTU after the implementation of the MSTU program at the Cleveland Clinic. A vascular neurologist evaluated the first 100 patients via telemedicine, and a neuroradiologist remotely assessed images obtained by mobile computed tomography (CT). Data were entered into the medical record and a prospective registry. MAIN OUTCOMES AND MEASURES The study compared the evaluation and treatment of patients on the MSTU with a control group of patients brought to the emergency department via ambulance during the same year. Process times were measured from the time the patient entered the door of the MSTU or emergency department, and any problems encountered during his or her evaluation were recorded. RESULTS Ninety-nine of 100 patients were evaluated successfully. The median duration of telemedicine evaluation was 20 minutes (interquartile range [IQR], 14-27 minutes). One connection failure was due to crew error, and the patient was transported to the nearest emergency department. There were 6 telemedicine disconnections, none of which lasted longer than 60 seconds or affected clinical care. Times from the door to CT completion (13 minutes [IQR, 9-21 minutes]) and from the door to intravenous thrombolysis (32 minutes [IQR, 24-47 minutes]) were significantly shorter in the MSTU group compared with the control group (18 minutes [IQR, 12-26 minutes] and 58 minutes [IQR, 53-68 minutes], respectively). Times to CT interpretation did not differ significantly between the groups. CONCLUSIONS AND RELEVANCE An MSTU using telemedicine is feasible, with a low rate of technical failure, and may provide an avenue for reducing the high cost of such systems.

An Analysis of Inflation Times During Balloon-Assisted Aneurysm Coil Embolization and Ischemic Complications

Background and Purpose— The introduction of balloon remodeling has revolutionized the approach to coiling of wide-neck aneurysms. We studied the effects of balloon inflation during coil embolization on ischemic complications. Methods— A retrospective review was undertaken of the most recent 147 patients undergoing balloon remodeling for unruptured intracranial aneurysm coil embolization at a single institution (81 balloon, 66 unassisted). All underwent postprocedural MRI. Results— Among patients in the “balloon” group, the mean total inflation time was 18 minutes (range, 1–43), a mean number of inflations of 4 (range, 1–9), a mean maximum single inflation time of 7 minutes (range, 1–19), a mean reperfusion time of 2.2 minutes between inflations, and an average procedure time of 2 hours and 10 minutes. Asymptomatic diffusion-weighted imaging abnormalities were detected on postprocedural MRI in 21.5% of patients and symptomatic lesions were identified in 3.8%. Both silent and symptomatic ischemic rates were similar in the internal control group. Patients with ischemic findings were older and more likely have diabetes; no differences were found with respect to total balloon inflation time, number of inflations, maximum inflation time, or reperfusion times. Conclusions— We found no significant relationship between balloon inflation practices and ischemic events. Older and diabetic patients were more likely to have ischemic events develop.

Addition of Hyperacute MRI Aids in Patient Selection, Decreasing the Use of Endovascular Stroke Therapy

Background and Purpose— The failure of recent trials to show the effectiveness of acute endovascular stroke therapy (EST) may be because of inadequate patient selection. We implemented a protocol to perform pretreatment MRI on patients with large-vessel occlusion eligible for EST to aid in patient selection. Methods— We retrospectively identified patients with large-vessel occlusion considered for EST from January 2008 to August 2012. Patients before April 30, 2010, were selected based on computed tomography/computed tomography angiography (prehyperacute protocol), whereas patients on or after April 30, 2010, were selected based on computed tomography/computed tomography angiography and MRI (hyperacute MRI protocol). Demographic, clinical features, and outcomes were collected. Univariate and multivariate analyses were performed. Results— We identified 267 patients: 88 patients in prehyperacute MRI period and 179 in hyperacute MRI period. Fewer patients evaluated in the hyperacute MRI period received EST (85 of 88, 96.6% versus 92 of 179, 51.7%; P<0.05). The hyperacute-MRI group had a more favorable outcome of a modified Rankin scale 0 to 2 at 30 days as a group (6 of 66, 9.1% versus 33 of 140, 23.6%; P=0.01), and when taken for EST (6 of 63, 9.5% versus 17 of 71, 23.9%; P=0.03). On adjusted multivariate analysis, the EST in the hyperacute MRI period was associated with a more favorable outcome (odds ratio, 3.4; 95% confidence interval, 1.1–10.6; P=0.03) and reduced mortality rate (odds ratio, 0.16; 95% confidence interval, 0.03–0.37; P<0.001). Conclusions— Implementation of hyperacute MRI protocol decreases the number of endovascular stroke interventions by half. Further investigation of MRI use for patient selection is warranted.