Abstract WMP2: Acute Stroke Treatment In Patients With Pre-exiting Disability: A Secondary Analysis Of The BEST-MSU Trial

Background: Few data exists on acute stroke treatment in patients with pre-existing disability (PD) since they are usually excluded from clinical trials.

Methods: A pre-specified subgroup analysis of tPA-eligible patients with PD enrolled in a prospective multicenter trial of Mobile Stroke Units (MSUs) vs standard management by emergency medical services (EMS). All patients had baseline mRS scores. Co-primary outcomes were mean utility-weighted modified Rankin Scale score (uw-mRS) and return to baseline mRS at 90 days. Linear and logistic regression models compared outcomes in patients with vs without PD, and patients with PD treated by MSU vs EMS. Time metrics, safety, quality of life, and health-care utilization were also compared.

Results: Of 1047 patients, 254 had baseline mRS >= 2 (159 MSU, 95 EMS; 31% mRS 2, 52% mRS 3, 17% mRS 4). Compared to patients without disability, patients with PD were older, had higher NIHSS, more comorbidities, less often lived at home, were treated slower, and had less thrombectomy. Patients with PD had worse 90-day uw-mRS (0.39 vs 0.80), higher mortality, more health-care utilization and worse quality of life than patients without PD. However, rates of symptomatic intracranial hemorrhage and final diagnoses of stroke mimics were similar between groups, and 52% of patients with PD returned to their baseline mRS. Patients with PD treated within the first hour had better 90-day uw-mRS than those treated later (0.48 vs 0.36, p=0.01). Comparing patients with PD treated by MSU vs EMS, time from last-known-well to tPA bolus was shorter (82 vs 111 min), and 24% vs 0% were treated in the first hour. Among patients with PD, MSU patients had non-significantly better 90-day uw-mRS (0.41 vs 0.35, p=0.09) and higher rate of returning to baseline mRS (56% vs 44%, p=0.09) than EMS patients. There was no interaction between either time to treatment (p=0.24) or MSU vs EMS group assignment (p= 0.42), 90-day uw-mRS, and PD vs no disability status.

Conclusion: Although outcomes after stroke are less favorable in patients with vs without PD, in a large, controlled trial, we found no interaction between baseline disability and the benefit of MSU treatment. Our data support the earliest treatment of acute stroke patients regardless of premorbid functional status.

Hemorrhage Enlargement Is More Frequent in the First 2 Hours: A Prehospital Mobile Stroke Unit Study

Background:

Hematoma enlargement (HE) after intracerebral hemorrhage (ICH) is a therapeutic target for improving outcomes. Hemostatic therapies to prevent HE may be more effective the earlier they are attempted. An understanding of HE in first 1 to 2 hours specifically in the prehospital setting would help guide future treatment interventions in this time frame and setting.

Methods:

Patients with spontaneous ICH within 4 hours of symptom onset were prospectively evaluated between May 2014 and April 2020 as a prespecified substudy within a multicenter trial of prehospital mobile stroke unit versus standard management. Baseline computed tomography scans obtained <1, 1 to 2, and 2 to 4 hours postsymptom onset on the mobile stroke unit in the prehospital setting were compared with computed tomography scans repeated 1 hour later and at 24 hours in the hospital. HE was defined as >6 mL if baseline ICH volume was < 20 mL and 33% increase if baseline volume >20 mL. The association between time from symptom onset to baseline computed tomography (hours) and HE was investigated using Wilcoxon rank-sum test when time was treated as a continuous variable and using Fisher exact test when time was categorized. Kruskal-Wallis and Wilcoxon rank-sum tests evaluated differences in baseline volumes and HE. Univariable and multivariable logistic regression analyses were conducted to identify factors associated with HE and variable selection was performed using cross-validated L1-regularized (Lasso regression). This study adhered to STROBE guidelines (Strengthening the Reporting of Observational Studies in Epidemiology) for cohort studies.

Results:

One hundred thirty-nine patients were included. There was no difference between baseline ICH volumes obtained <1 hour (n=43) versus 1 to 2 hour (n=51) versus >2 hours (n=45) from symptom onset (median [interquartile range], 13 mL [6–24] versus 14 mL [6–30] versus 12 mL [4–19]; P =0.65). However, within the same 3 time epochs, initial hematoma growth (volume/time from onset) was greater with earlier baseline scanning (median [interquartile range], 17 mL/hour [9–35] versus 9 mL/hour [5–23]) versus 4 mL/hour [2–7]; P <0.001). Forty-nine patients had repeat scans 1 hour after baseline imaging (median, 2.3 hours [interquartile range. 1.9–3.1] after symptom onset). Eight patients (16%) had HE during that 1-hour interval; all of these occurred in patients with baseline imaging within 2 hours of onset (5/18=28% with baseline imaging within 1 hour, 3/18=17% within 1–2 hour, 0/13=0% >2 hours; P =0.02). HE did not occur between the scans repeated at 1 hour and 24 hours. No association between baseline variables and HE was detected in multivariable analyses.

Conclusions:

HE in the next hour occurs in 28% of ICH patients with baseline imaging within the first hour after symptom onset, and in 17% of those with baseline imaging between 1 and 2 hours. These patients would be a target for ultraearly hemostatic intervention.

Abstract P424: Hemorrhage Enlargement in the First Two Hours: A Mobile Stroke Unit Study

Objective: Hematoma enlargement (HE) occurs after spontaneous intracerebral hemorrhage (ICH) but no studies have evaluated the frequency of HE in first 1-2 h after symptom onset. We evaluated HE in the first 2h after onset using a mobile stroke unit (MSU).

Methods: Patients with spontaneous ICH within 4.5h were evaluated on the Houston MSU between 5/2014 and 4/2020. Baseline CT scans from the MSU were compared with scans repeated within 1h [median 67min (IQR 57-82 min]. Significant HE was defined as >6 ml if baseline volume was <20 ml and 30% increase if baseline volume >20 ml. Kruskal-Wallis and Wilcoxon rank sum tests evaluated differences in baseline volumes and HE. Intraclass correlation coefficient (ICC) evaluated agreement between two ICH measurement techniques (ABC/2 vs semi-automated).

Results: 163 patients had baseline CTs, of whom 60 had repeat 1h CTs (table 1). There was no difference between baseline volume and time of CT from symptom onset {<1h vs 1-2h vs >2h median (IQR) = 14 ml (6-28) vs. 16 ml (7-32) vs. 12 ml (4-24), P=0.42)}. There was also no correlation between time from onset and difference in volume between baseline and 1 h repeat imaging. However, 9/60 patients had significant HE from baseline to 1 h repeat imaging; all of these occurred in patients initially imaged within 2 h of onset (6/24 within 1h, 3/20 within 1-2h) (P=0.03) (figure 1). High reliability was seen between the two methods measuring volumes (ICC = 0.84).

Conclusion: Significant HE in the next hour occurs in 25% of ICH patients imaged within the first hour after symptom onset, and 17% imaged between 1-2 hours of onset. These patients would be a target for ultra-early hemostatic intervention.

Abstract P132: Successful Conduct of an Acute Stroke Clinical Trial During COVID

Introduction: Most clinical research stopped during COVID due to possible impact on data quality and personnel safety. We aimed to assess the impact of COVID on study conduct at sites that continued to enroll patients during the pandemic.

Methods: BEST-MSU is an ongoing study of Mobile Stroke Units (MSU) vs standard management of tPA eligible acute stroke patients in the pre-hospital setting. MSU personnel include a vascular neurologist via telemedicine, and a nurse, CT tech, and medics on board using appropriate PPE. During COVID, consent, 90 d mRS and EQ5D could be obtained by phone instead of in person, otherwise management was the same. We compared patient demographics, study metrics, and infection of study personnel during intra- vs pre-COVID eras.

Results: Four of 6 BEST-MSU sites continued to enroll during COVID. There was no difference in intra- (n= 41) vs pre- (n= 763) COVID enrolled tPA eligible patients’ age, sex, race (45% vs 41% Black), ethnicity (23% vs 19% Hispanic), or NIHSS (12 vs 12). MSU alert frequency did not change, but percent of screened patients enrolled and treated with tPA declined to 12% from 23% (p<.001); enrollment correlated with local stay at home and reopening (fig). There was no difference in alert to MSU arrival or arrival to tPA times, but on-scene time was 2 min longer (p=.04). There was no difference in ED door to CT, tPA, or EVT times, hospital LOS, discharge disposition, or 90d mRS or EQ5D accuracy. One MSU nurse tested positive but did not require medical care.

Conclusion: Clinical research in the pre-hospital setting can be carried out accurately and safely during a pandemic. Study enrollment and tPA treatment rates declined, but otherwise there was no difference in patient demographics, deterioration of study processes, or serious infection of study staff.

Abstract 3: Early Recanalization of Large Vessel Occlusions by tPA on the Mobile Stroke Unit

Introduction: The benefit of intravenous tPA in acute ischemic stroke patients with large vessel occlusions (LVOs) is limited but time dependent. We evaluated pre-hospital treatment with tPA on the Mobile Stroke Unit (MSU) to explore the recanalization rate in patients with LVOs and its effect on clinical improvement upon ED arrival.

Methods: Prospectively derived data were analyzed from patients on the Houston MSU who were treated with tPA and had LVOs identified by hyperdense artery on MSU CT or arterial occlusion on MSU CTA. The primary outcome was early recanalization, categorized as resolution of LVO on repeat vascular imaging in the ED or on emergent angiography versus no recanalization. Secondary outcome was change in baseline NIHSS at 24 hours. Differences in NIHSS were evaluated using Wilcoxon rank sum test with continuity correction.

Results: Seventy-one patients received tPA and had proximal LVOs both in the anterior and posterior circulation. Eleven had recanalization on CTA upon ED arrival (15.5%), while 7 had recanalization on emergent angiography (9.9%). The total early recanalization rate with tPA was 25.4%. Forty-seven patients with persistent LVOs on ED arrival (66.2%) underwent endovascular thrombectomy (EVT). Time from symptom onset (last known normal) to tPA bolus did not differ significantly between the early recanalization vs non-early recanalization groups (64.5 minutes [IQR 43.0-78.5] vs 64.0 minutes [52.5-92.0]; p = 0.41). Early recanalization resulted in greater improvement in baseline to ED arrival NIHSS (median NIHSS change 4.0 [0-11.8] vs 0 [0-3.5]; p = 0.01). There were no differences in ED arrival to 24 hour NIHSS between the early recanalization versus non-early recanalization groups irrespective of EVT.

Conclusions: Recanalization by ED arrival occurs in 25% of LVO patients with tPA treatment on a MSU and was associated with early clinical improvement. Subsequent EVT did not “make up” for the clinical benefit of early recanalization.

Successful conduct of an acute stroke clinical trial during COVID

Most clinical research stopped during COVID due to possible impact on data quality and personnel safety. We aimed to assess the impact of COVID on acute stroke clinical trial conduct at sites that continued to enroll patients during the pandemic. BEST-MSU is an ongoing study of Mobile Stroke Units (MSU) vs standard management of tPA-eligible acute stroke patients in the pre-hospital setting. MSU personnel include a vascular neurologist via telemedicine, and a nurse, CT technologist, paramedics and emergency medicine technicians on-board. During COVID, consent, 90-day modified Rankin Scale (mRS) and EQ5D were obtained by phone instead of in-person, but other aspects of management were similar to the pre-COVID period. We compared patient demographics, study metrics, and infection of study personnel during intra- vs pre-COVID eras. Five of 6 BEST-MSU sites continued to enroll during COVID. There were no differences in intra- (n = 57) vs pre- (n = 869) COVID enrolled tPA eligible patients’ age, sex, race (38.6% vs 38.0% Black), ethnicity (15.8% vs 18.6% Hispanic), or NIHSS (median 11 vs 9). The percent of screened patients enrolled and adjudicated tPA eligible declined from 13.6% to 6.6% (p < .001); study enrollment correlated with local stay-at-home and reopening orders. There were no differences in alert to MSU arrival or arrival to tPA times, but MSU on-scene time was 5 min longer (p = .01). There were no differences in ED door to CT, tPA treatment or thrombectomy puncture times, hospital length of stay, discharge disposition, or remote vs in-person 90-day mRS or EQ5D. One MSU nurse tested positive but did not require hospitalization. Clinical research in the pre-hospital setting can be carried out accurately and safely during a pandemic. tPA eligibility rates declined, but otherwise there were no differences in patient demographics, deterioration of study processes, or serious infection of study staff.

Trial registration:NCT02190500

Abstract 99: Mobile Stroke Unit CTA and Direct Notification of Interventional Team Shortens Door-to-Puncture Time by One Hour

Introduction: Endovascular thrombectomy (ET) is an effective but time sensitive treatment of acute ischemic stroke. Time from Emergency Department (ED) arrival to start of ET (door-to-puncture time, DTPT) is a modifiable metric. One of the most time consuming steps in prolonging DTPT is identification of large vessel occlusion (LVO) by CT angiography (CTA). BEST-MSU is a prospective multicenter comparative effectiveness study of tPA-eligible patients managed on a mobile stroke unit (MSU) vs Emergency Medical Services (Standard Management, SM). After discovering that DTPT was greater than 60 minutes in both groups at three BEST-MSU centers in 2018, we began to routinely obtain CTA on the MSU and directly alert the ET team at receiving hospitals if a LVO was identified. We hypothesized this would shorten DTPT by over 30 minutes.

Methods: In this single center experience, we compared the median (interquartile range, IQR) DTPT and MSU on-scene time for MSU patients having on-board CTA and then ET from 9/2018 to 7/2019 to corresponding MSU ET patients (excluding any that had on-board CTA) from 8/2014 to 8/2018. All CTAs were completed after tPA bolus and during tPA infusion on a Ceretom 8 slice scanner with OptiStat hand injector. All imaging occurred on-scene with the MSU stationary. Consent was obtained for all patients and strict radiation safety guidelines followed.

Results: 13 consecutive patients having CTA on-board the MSU and then ET were compared to 84 patients in the pre-on-board CTA group. Baseline characteristics including median NIHSS score (20 in both groups) and frequency of tPA (85% on-board CTA vs 89% pre-on-board CTA) were comparable. Median DTPT was 60 minutes shorter with on-board CTA and direct notification of the interventional team from the MSU; 34 minutes (IQR 30-57) vs 94.5 minutes (IQR 69.75-117.25) (p < 0.001). Despite the additional time to obtain the CTA on the MSU, on-scene time was only slightly prolonged and did not offset the reduction in DTPT (on-board CTA 30 minutes (IQR 28-33) vs pre-on-board CTA 27 minutes (IQR 23-31) (p = 0.01).

Conclusion: Pre-hospital identification and notification of LVO by a MSU allows a one hour reduction of DTPT, and can be utilized to establish a direct to angiosuite protocol.

Emergency Department Door-to-Puncture Time Since 2014

Background and Purpose- The impact of a mobile stroke unit (MSU) on access to intraarterial thrombectomy (IAT) is a prespecified BEST-MSU substudy (Benefits of Stroke Treatment Delivered Using a Mobile Stroke Unit Compared to Standard Management by Emergency Medical Services). On the MSU, IAT decision-making steps, such as computed tomography, neurological exam, and tPA (tissue-type plasminogen activator) treatment are completed before emergency department arrival. We hypothesized that such pre-ED assessment of potential IAT patients on an MSU improves the time from ED arrival to skin puncture time (door-to-puncture-time, DTPT). Methods- BEST-MSU is a prospective comparative effectiveness study of MSU versus standard management by emergency medical services (EMS). We compared ED DTPT among the following groups of MSU and EMS patients: all IAT patients, IAT patients post-tPA, and IAT patients post-tPA meeting thrombolytic adjudication criteria over the first 4 years of the study. Results- From August 2014 to July 2018, a total of 161 patients underwent IAT. Ninety-four patients presented to the ED via the MSU and 67 by EMS. One hundred forty patients received tPA before IAT, 85 in the MSU arm, and 55 in the EMS arm. One hundred twenty-six patients received tPA within thrombolytic adjudication criteria: 76 MSU and 50 EMS. DTPT in minutes was shorter for MSU patients (all IAT MSU versus EMS 89 versus 99, P=0.01; IAT post-tPA MSU versus EMS 93 versus 100, P=0.03; and IAT post-tPA within adjudicated criteria MSU versus EMS 93 versus 99.5, P=0.03). From 2014 to 2018, DTPT decreased at a faster rate for EMS compared with MSU-managed patients, improving by about an hour. Conclusions- Pre-ED IAT evaluation on an MSU results in faster DTPT compared with arrival by EMS. Since 2014, dramatic improvement in ED IAT metrics has attenuated this difference. However, DTPT in all groups indicates substantial room for improvement.

Abstract TMP11: Emergency Room Door-to-Puncture Time Since 2015: Observations From the BEST-MSU Study

Introduction: The impact of a Mobile stroke unit (MSU) on access to Endovascular Thrombectomy (ET) is a pre-specified BEST-MSU sub-study. On the MSU, ET decision-making steps such as CT, neurologic exam, and tPA treatment are completed prior to Emergency Room (ER) arrival. We hypothesized that such pre-ER assessment of potential ET patients on a MSU improves metrics.

Methods: BEST-MSU is a prospective comparative effectiveness study of MSU vs Standard Management by Emergency Medical Services (SM). We compared ER door-to-puncture-time (mins, DTPT) among the following groups of MSU and SM patients: all ET patients (ETP), ET patients post-tPA (ETT), and ET patients post-tPA meeting thrombolytic adjudication criteria (ETTA) over the first four years of the study.

Results: There were 161 ETP (67 SM, 94 MSU), 140 ETT (55 SM, 85 MSU), and 126 ETTA (50 SM, 76 MSU) patients. DTPT was shorter for MSU patients (ETP 89 vs 99, p=0.01; ETT 93 vs 100, p=0.03; ETTA 93 vs 99.5, p=0.03). From 2015 to 2018, DTPT decreased at a faster rate for SM compared with MSU-managed patients, improving by about an hour (Figure).

Conclusion: Pre-ER ET evaluation on a MSU results in faster DTPT. Since 2015, dramatic improvement in ER ET metrics has attenuated this difference. However, DTPT of 90-100 mins in all groups indicates substantial room for improvement.

Should mild or moderate stroke patients be admitted to an intensive care unit?

BACKGROUND AND PURPOSE

Inhospital placement of patients with mild (National Institutes of Health Stroke Scale [NIHSS] score <8) or moderate (NIHSS 8 through 16) acute strokes is variable. We assessed the outcome of such patients based on intensive care unit (ICU) versus general ward placement.

METHODS

We reviewed 138 consecutive patients admitted within 24 hours of stroke onset to 2 physically adjacent hospitals with different admitting practices. Outcome measures included complication rates, discharge Rankin scale score, hospital discharge placement, costs, and length of stay (LOS).

RESULTS

Hospital A, a 626-bed university-affiliated hospital, admitted 43% of mild and moderate strokes (MMS) to an ICU (26% of mild, 74% of moderate), whereas hospital B, a 618-bed community facility, admitted 18% of MMS to an ICU (3% of mild, 45% of moderate; P<0.004). There were no significant differences in outcomes between the 2 hospitals. Analysis of only patients admitted to hospital A, and of all patients, demonstrated that mild stroke patients admitted to the general ward had fewer complications and more favorable discharge Rankin scale scores than similar patients admitted to an ICU. There was no statistically significant difference in LOS, but total room costs for a patient admitted first to the ICU averaged $15 270 versus $3638 for admission directly to the ward.

CONCLUSIONS

While limited by the retrospective nature of our study, routinely admitting acute MMS patients to an ICU provides no cost or outcomes benefits.

Neurologic complications after coronary artery bypass grafting

Although outcomes from coronary artery bypass grafting (CABG) surgery have improved in general, there has been little or no improvement in the incidence of postoperative stroke or neurologic dysfunction. Several studies have identified factors that increase the CABG patient's risk for developing a stroke and neurologic complications. It is important to identify those patients at increased risk and differentiate among stroke, delirium, and seizures. Post-CABG patients need to be monitored for neurological dysfunction with appropriate assessments. Neurologic complications must be appropriately managed to optimize patient recovery.

Clinical features of moyamoya disease in the United States

BACKGROUND AND PURPOSE

We report the clinical features and longitudinal outcome of the largest cohort of patients with moyamoya disease described from a single institution in the western hemisphere. Moyamoya disease in Asia usually presents with ischemic stroke in children and intracranial hemorrhage in adults.

METHODS

Our study population included all patients with moyamoya disease evaluated at a university hospital in Houston, Texas from 1985 through 1995 (n = 35). We used Kaplan-Meier methods to estimate individual and hemispheric stroke risk by treatment status (medical versus surgical). Predictors of neurological outcome were assessed.

RESULTS

The ethnic background of our patients was representative of the general population in Texas. The mean age at diagnosis was 32 years (range, 6 to 59 years). Ischemic stroke or transient ischemic attack was the predominant initial symptom in both adults and children. Of the 6 patients with intracranial hemorrhage, 5 had an intraventricular site of hemorrhage. The crude stroke recurrence rate was 10.3% per year in 116 patient-years of follow-up. Twenty patients underwent surgical revascularization, the most common procedure being encephaloduroarteriosynangiosis. The 5-year risk of ipsilateral stroke after synangiosis was 15%, compared with 20% for medical treatment and 22% overall for surgery.

CONCLUSIONS

Our observations indicate that moyamoya disease may have a different clinical expression in the United States than in Asia, and may demonstrate a trend toward a lower stroke recurrence rate and better functional outcome after synangiosis.

Education to improve stroke awareness and emergent response. The NINDS rt-PA Stroke Study Group

Patients delay in responding to stroke as an emergency in part because they have deficient information about the disease and treatment. Healthcare providers may also have a lack of information about stroke assessment and management, which could attribute to delays in patient care. In order to provide early, rapid stroke treatment in eligible persons, the public and the healthcare community must be informed. Information on stroke risk, symptoms and treatment should be provided to those likely to experience stroke, the general public and the emergency and medical communities who may witness and intervene when stroke occurs. Programs developed at the eight centers of the National Institute of Neurological Disorders and Stroke (NINDS) rt-PA stroke trial provide a sampling of approaches that increase awareness in these groups. Lessons learned include: 1. Program planning should start with a community needs assessment. 2. A variety of strategies can be applied to meet the community needs and resources. 3. Educational principles and models should be utilized in planning effective programs. 4. The message must be simple: "Stroke is an emergency. Time is brain".

Nursing care of acute stroke patients after receiving rt-PA therapy. The NINDS rt-PA Stroke Study Group

Treatment with tissue plasminogen activator (rt-PA) for acute stroke requires intensive care of the patient. The risk of thrombolytic therapy and the need for rapid interventions make it clear that the nursing role during this time is crucial. Nurses should be familiar with safe dosage and administration of rt-PA for stroke, which is clearly different than administration of rt-PA for myocardial infarction. Furthermore, thrombolytic stroke treatment must be accompanied by intensive neurological monitoring to observe for complications. Intracerebral hemorrhage is usually accompanied by an acute change in neurological status and vital sign instability. Intensive monitoring of neurologic condition, vital signs, cardiac status and other standard critical care practices must be initiated immediately to optimize patient outcome.

Code Stroke: rapid transport, triage and treatment using rt-PA therapy. The NINDS rt-PA Stroke Study Group

With the approval of rt-PA therapy for ischemic stroke, stroke care has acutely transitioned from focusing on rehabilitative services to emergency services. This treatment, which must be initiated within the first three hours after the onset of stroke symptoms, requires reorganization of current management approaches. Developing a Code Stroke Team facilitates this process and helps to identify potential thrombolysis candidates. A pathway to deliver rapid care begins with 911 notification and transport, emergency department triage and procedures, and moves through the initiation of thrombolytic therapy. We call this pathway "Code Stroke".

Overview: hyperacute rt-PA stroke treatment. The NINDS rt-PA Stroke Study Group

Ischemic stroke remains a significant problem in the United States. Complex intracellular metabolic events occur leading to cell death. A search for treatments to prevent this ischemic process continues. Thrombolytic agents, recently developed and tested, may lessen the disabling effects of stroke.

Nursing management of acute complications following rt-PA in acute ischemic stroke. The NINDS rt-PA Stroke Study Group

In the National Institutes of Neurologic Disorders and Stroke (NINDS) recombinant tissue plasminogen activator (rt-PA) stroke trial, the primary adverse events monitored were intracranial hemorrhage (ICH), systemic bleeding, death and new stroke. Nurses caring for the study patients noted these adverse events and other complications. In addition to what is known about acute ischemic stroke (AIS), the NINDS trial provides further information for optimal care of this specific group of patients. The complications found in this trial require expert nursing care to monitor, prevent and intervene, making clinical decisions relevant to the patients needs. The critical decision-making process must be grounded in knowledge of acute stroke physiology and thrombolysis.

Pathophysiology and mechanisms of acute ischemic stroke. The NINDS rt-PA Stroke Study Group

Stroke is a leading cause of death and disability among Americans. The recent US Food and Drug Administration approval of recombinant tissue plasminogen activator (rt-PA, Activase) for the treatment of acute ischemic stroke offers the first proven therapy to reverse or ameliorate stroke symptoms. rt-PA is thought to restore circulation in the patient with acute ischemic stroke by dissolving an occluding thrombus or embolus. A basic understanding of cerebral circulation and the mechanism by which stroke compromises brain tissue is fundamental to appreciating this new therapy. The importance of prompt stroke diagnosis and treatment cannot be underestimated.

Magnetic resonance angiography demonstrates vascular healing of carotid and vertebral artery dissections

BACKGROUND AND PURPOSE

Dissection of the carotid and vertebral arteries is most accurately diagnosed with conventional angiography. MR techniques are sensitive for detecting the abnormalities associated with dissection but may lack specificity. We hypothesized that MR may be useful for serial monitoring of dissection and may therefore guide therapy.

METHODS

All patients with angiographically proven carotid and/or vertebral artery dissection from July 1994 to June 1996 were followed for a median duration of 10.5 months. Of these 29 patients (44 vessels), 18 were concurrently evaluated with MR, and a target group of 9 patients (17 vessels) was prospectively followed with MR at 3-month intervals.

RESULTS

In the 18 patients with both imaging studies at baseline, angiography revealed 30 dissected vessels while MR detected 27 (90%). In the target group of 9 patients, initial MR identified 15 of the 17 dissections diagnosed with angiography. Serial MR revealed complete healing in 5 vessels, improvement in 6 vessels, no change in 4 vessels, and worsening in 2 vessels. The radiographic features most likely to resolve were stenosis and mural hematoma, while occlusion and luminal irregularity tended to persist. Late ischemic events occurred in 2 patients, both with persistent MR evidence of dissection, one while subtherapeutic on warfarin therapy and the other occurring 1 week after warfarin was discontinued.

CONCLUSIONS

MR is a reliable noninvasive method for following the vascular response to treatment and may guide the course of a clinical trial comparing medical therapies for carotid and vertebral artery dissection.

Subjective experiences of 24 patients dramatically recovering from stroke

BACKGROUND

There are no reports describing patients' perception of having a stroke and then dramatically recovering.

SUMMARY OF REPORT

We interviewed 24 patients randomized at our center to intravenous tissue plasminogen activator or placebo in an ongoing multicenter blinded prospective study. These patients demonstrated at least 50% improvement or an absolute improvement of 5 points on the National Institutes of Health Stroke Scale during the first 24 hours after treatment, with 7 patients returning completely to normal. Twelve of 24 of the strokes involved the right middle cerebral artery, 2 of 24 the right posterior cerebral artery, 8 of 24 the left middle cerebral artery, and 2 of 24 the basilar artery territory. CT scans at 24 hours or 1 week showed infarction in 19 of 24. Most patients (19 of 24) could clearly recall the exact circumstances involving the onset of their stroke, but only 12 of 24 were aware of the magnitude of their neurological deficit (7 of 14 right hemisphere and 4 of 8 left hemisphere patients). Only 6 of 24 were aware of their improvement when it occurred (3 of 14 right hemisphere and 2 of 8 left hemisphere patients). Five of 24 remembered positive phenomena such as warmth or tingling during their recovery, and only 2 patients demonstrated euphoria. Most patients seemed peculiarly unaware or blasé about their deficit and improvement.

CONCLUSIONS

Most patients with acute stroke are not aware of the severity of their problem, and recovering patients do not remember important events during the next 24 hours. This occurs with either right or left hemisphere lesions and may have a significant impact on early stroke recognition.

Current emergency department management of stroke in Houston, Texas

BACKGROUND AND PURPOSE

This study describes emergency department (ED) management of stroke in Houston, Tex, in 1992 to identify delays and deficiencies in recognition and management of stroke patients in various hospital subtypes and to quantitate the impact of a rapid response stroke team.

METHODS

ED logs of eight hospitals were retrospectively screened, and 112 patients with suspected acute stroke onset within 6 hours were identified. EDs were divided into four groups based on hospital size (175 to 979 beds), acuity, number of stroke admissions (50/y to 210/y), and availability of neurological consultations. The intervals from stroke onset to triage, examination by a physician, neurological evaluation, computed tomography (CT) and other tests, vital signs, and treatments were recorded.

RESULTS

The average time from stroke to ED arrival was 115 minutes, and times from ED arrival to examination by a physician and CT scan were 28 and 100 minutes, respectively, with little variability among hospital groups except that the public hospital was slower. Neurological examinations were poorly documented in community and public hospitals. The presence of a stroke team shortened the time to examination by a physician and to CT by 13 and 63 minutes, respectively, and increased the number of patients admitted to the intensive care unit. Blood pressure was excessively lowered in 31% of hypertensive patients, and hypotonic dextrose intravenous fluids were given to 69% of all patients.

CONCLUSIONS

Transport, initial evaluation, and ED care of acute stroke patients are currently slow and often inexpert in all types of hospitals. A stroke team can speed initial ED management.

Pilot study of nicardipine for acute ischemic stroke

The author performed a pilot study of nicardipine (NC), a Ca(+)+ channel blocker, to study its dosing, toxicity, and possible efficacy for hemispheric cerebral infarction within 12 hours (mean 6.9 hr) of onset to determine the advisability of proceeding with a multi-centered controlled trial. NC was administered IV (3 to 7 mg/hr) X 72 hours by titrating dose to mean arterial blood pressure (MABP not less than 10% of baseline), then orally X 30 days. Forty-three patients have been entered; mean age 63 (range 34-89), 25 male and 18 female. Only 3 had CT evidence of infarct on entry. Results have shown improvement in a 100-point (pt) graded exam (40 pts at entry, 68 pts at 3 months). Of 20 patients completing 3 months' evaluation, 17 improved and none worsened. Sixteen out of 20 were at home and 8 had minimal or no impairment. Mean Barthel's index was 72. Mean maximal serum NC level was 75 ng/mL. MABP decreased from 103 (entry) to 83 (72 hours). A larger controlled study is warranted to determine the efficacy of NC for acute cerebral infarct.

Prediction of carotid stenosis progression by lipid and hematologic measurements

We followed 19 men and 19 women with asymptomatic carotid stenosis up to 30 months to determine whether hematologic or lipid abnormalities could identify those individuals developing progressing carotid atherosclerosis (defined as an increase in mean percent stenosis greater than or equal to 19% or an increase in a single region of greater than or equal to 23%) on B-mode carotid ultrasonography performed at 2- to 6-month intervals. Our patients demonstrated increased beta-thromboglobulin, platelet factor 4, and fibrinogen compared with age-matched controls. Eight patients developed progression of carotid stenosis, and this group had higher baseline low-density lipoprotein (LDL) and fibrinogen than the 30 nonprogressing patients. Multiple regression analyses of age, sex, smoking, coronary artery disease, peripheral vascular disease, diabetes, hypertension, and baseline high-density lipoprotein (HDL), HDL2, HDL3, LDL, beta-thromboglobulin, platelet factor 4, and fibrinogen identified coronary artery disease and elevated LDL and fibrinogen as the only independent variables significantly associated with the progressing group. We conclude that, in patients with carotid atherosclerosis, a combination of coronary artery disease and elevated LDL and fibrinogen will predict with 88% accuracy whether the patient will have progressing carotid stenosis.