"Telestroke" : the application of telemedicine for stroke

BACKGROUND: Time is of the essence for effective intervention in acute ischemic stroke. Efforts including stroke teams that are "on call" around-the-clock are emerging to reduce the time from emergency room arrival to evaluation and treatment. SUMMARY OF COMMENT: Based on the results of the NINDS rt-PA Stroke Trial, which demonstrated both clinical effectiveness in reducing neurological deficits and disability and cost savings to health care systems, many community hospitals and managed-care organizations are exploring methods to enhance and expedite acute stroke care in their local communities. Only a small fraction of acute stroke victims is currently treated with thrombolytics (<1.5% nationally), and few benefit from the expertise and experience of the stroke teams. It is essential to develop new paradigms to improve acute stroke care in all settings, rural and urban. Rapid linkages to expert stroke care can help the underserved areas. Telemedicine for stroke, "Telestroke, " uses state-of-the-art video telecommunications that may be a potential solution and may maximize the number of patients given effective acute stroke treatment across the country and across the world. Telestroke could facilitate remote cerebrovascular specialty consults from virtually any location within minutes of attempted contact, adding greater expertise to the care of any individual patient. This model also has the potential to enhance patient entry into clinical trials. Telestroke would enhance stroke education through the use of Internet-based interactives for health-care professionals and patients. Education would be facilitated through the creation of telecommunication-linked classes providing interactive information on stroke care and prevention to places where they are otherwise not available. Health-care professionals will gain experience and expertise through the interaction with a remote expert--telementoring. Telestroke provides an excellent medium for data collection and an unprecedented opportunity for quality assurance. Monitoring of an entire tele-interaction can offer real-time assessments, which can then be analyzed in-depth at a later date for unique insights into health-care delivery. Prehospital use of telemedicine for stroke is already being piloted, linking patients in the ambulance to the emergency department. Legal and economic parameters must be established for telemedicine in the areas of reimbursement, liability, malpractice insurance, licensing, and credentialing. Issues of protection of privacy and confidentiality, informed consent, product liability, and industry standards must be addressed to facilitate the use of this new and potentially useful technology. CONCLUSIONS: Computer-based technology can now be used to integrate electronic medical information, clinical assessment tools, neuroradiology, laboratory data, and clinical pathways to bring state-of-the-art expert stroke care to underserved areas.     

Observations of the treatment of women in the United States with myocardial infarction: a report from the National Registry of Myocardial Infarction-I

BACKGROUND: To determine whether there are sex differences in the demographics, treatment, and outcome of patients with acute myocardial infarction in the United States, data from the National Registry of Myocardial Infarction-I from September 1990 to September 1994 were examined. METHODS: The National Registry of Myocardial Infarction-I is a national observational database consisting of 1234 US hospitals in which each hospital submits data from each patient with acute myocardial infarction to a central data collection center. For these analyses, the following variables were examined in 354 435 patients with acute myocardial infarction: demographics; use of medical therapy including thrombolytic agents; use of procedures including cardiac catheterization, percutaneous transluminal coronary angioplasty, and coronary artery bypass surgery; length of hospital stay; adverse events (stroke, major bleeding, or recurrent myocardial infarction); and causes of death. RESULTS: In comparison with men, women experiencing acute myocardial infarction in the United States are older, with 55.7% older than 70 years. Women have a higher mortality rate than men even when controlled for age and die less often from arrhythmia but more often from cardiac rupture whether or not thrombolytic therapy is used. Treatment with aspirin, heparin, or beta-blockers is less frequent in women. When thrombolytic therapy is used, women are treated an average of almost 14 minutes later than men and experience a greater incidence of major bleeding. Cardiac catheterization, percutaneous transluminal coronary angioplasty, and coronary artery bypass surgery are used less often in women. CONCLUSIONS: Observations from the National Registry of Myocardial Infarction-I document important sex differences in demographics, treatment, and outcome of patients with acute myocardial infarction in the United States.     

Duration of glutamate release after acute ischemic stroke

BACKGROUND AND PURPOSE: High levels of glutamate in plasma and cerebrospinal fluid (CSF) have been demonstrated in patients with acute ischemic stroke. The duration of this excitatory amino acid release has not been studied, and therefore the window of opportunity of treatment with glutamate antagonists is unknown. The aim of this investigation was to study the duration of the glutamate increase in patients with stable and progressing ischemic stroke. METHODS: Glutamate in CSF was measured by high-performance liquid chromatography in 184 patients with an acute cerebral infarction of less than 24 hours' duration and in 43 control subjects. RESULTS: Among the 120 patients with stable ischemic stroke, median glutamate levels were significantly lower- and within the reference range of control subjects-in those patients studied 6 to 24 hours from onset of symptoms than in patients studied in the first 6 hours (3 [range, 2 to 10] versus 5 mumol/L [range, 2 to 17]; P < .0001). In 64 patients with progressing ischemic stroke, glutamate concentrations measured at any time interval during the first 24 hours from onset were significantly higher than in the stable stroke and control groups. CONCLUSIONS: The presence of glutamate increase in the CSF cannot be documented for greater than 6 hours in stable ischemic stroke. The sustained elevation of glutamate observed in progressing stroke suggests that the window to prevent neurological deterioration may be wider.     

Further evolution toward effective therapy for acute ischemic stroke

The effective treatment of acute ischemic stroke remains an important goal of modern medicine and substantive advances are occurring. Recently, thrombolytic therapy with tissue-type plasminogen activator was approved for selected patients with acute ischemic stroke when therapy is started within 3 hours of onset. Streptokinase therapy for acute ischemic stroke has not been shown to be effective and is associated with an increased risk of hemorrhage, although it was not evaluated as early after stroke onset as tissue-type plasminogen activator. Various types of neuroprotective interventions are effective in animal models, but none has yet been proven effective in patients. In the future, combinations of thrombolytic and neuroprotective drugs may be used to attempt maximum rates of recovery after acute ischemic stroke. For combination therapy to achieve its maximum potential, patients with acute ischemic stroke will have to be carefully selected and treated.     

Intracranial vascular involvement of brain pathologies and venous occlusions

In this paper, the authors present the contribution of CT and MRI to the diagnosis of acute stroke caused by arterial or venous occlusion. The term "early" used in this context means within 6 h of the onset of symptoms. Signs of early ischemic edema are subtle and sometimes difficult to detect by CT or MRI. The purpose of this presentation is to familiarize the clinician and the radiologist with the subtle brain parenchymal changes seen within the first 6 h after onset of symptoms, in order to improve detection of early ischemic infarction and to improve patient care.     

Evaluation of non-cerebral complications in light of ischemic stroke severity

Extracerebral complications which were observed in great number of ischemic stroke patients increased the risk of death and disability. Pneumonia, myocardial infarction, pulmonary embolisms and urinary tract infections are most often. We considered the influences of extracerebral complications on anterior circulation territory disturbances. A cohort of 1697 patients with first-ever ischemic stroke within anterior circulation region was evaluated. Patients were divided into three groups: A, B, C according to the heaviness of stroke. We understood the heaviness of stroke as a degree of cerebral disfunction occurring within the first 24 hours of the onset and assessed it using Clinical Groups of the Whole Body Activity (CG WBM). CG WBM is an original classification, a three-degree one, prepared by Department of Neurology University School of Medicine Sciences in Bydgoszcz. The rate of complications was statistically significantly lower in group A with the mild course of ischemic stroke than in group B with moderate or in group C with the severe course of ischemic stroke. Pneumonia, myocardial infarction and pulmonary embolism were recognized more often in patients with fatal outcome. The amount of extracerebral complications raised with the severity of the ischemic stroke.     

Possibilities and limitations of thrombolysis. Benefits and risk in acute myocardial infarct, lung embolism, pelvic and leg vein thrombosis as well as cerebrovascular accidents

The indications for thrombolytic therapy in acute myocardial infarction, pulmonary embolism, deep venous thrombosis and ischemic stroke are reviewed on the basis of a risk-benefit analysis. There is strong evidence that thrombolysis benefits the majority of patients with acute myocardial infarction. Nevertheless, the overall proportion of patients actually receiving this therapy is disappointingly low (10-30%). Efforts are mainly required in minimizing delays in initiating thrombolysis (patient, doctor, in-hospital) and in providing thrombolytic therapy to an extended proportion of qualifying patients. This implies that many traditional but inappropriate exclusion criteria (e.g. age, presentation 6 to 12 hours after onset of symptoms, hypertension, reinfarction, brief cardiopulmonary resuscitation) are unfounded. Depending on duration of symptoms, infarct localization and age, we favor a differentiated thrombolytic regimen with rt-PA or streptokinase. In contrast to acute myocardial infarction, the risk-benefit ratio for the other thrombotic disorders discussed favours thrombolytic therapy only in a minority of carefully selected patients.     

Biochemical markers in acute myocardial infarct

Exact and early diagnosis of acute myocardial infarction is essential for the subsequent routine management of this frequent cardiovascular disease. At present, the clinical biochemistry possesses a set of more or less cardiospecific protein markers for early detection of myocardial ischemic damage. After the admission of patient to the hospital, serial estimations of rather non-specific enzyme activities (creatine kinase, its MB-izoenzyme, lactate dehydrogenase, hydroxybutyrate dehydrogenase) are currently used for the detection of acute myocardial infarction and for the further monitoring of the patient and managing his therapy. In the past decade, many cardiospecific biochemical markers were discovered and gradually introduced into the routine clinical practice. The most perspective markers are some molecules of contractile proteins of heart myofibrils (troponins, myosin chains) as well as "rediscovered" myoglobin. The aim of this review article is to inform about the commonly used, as well as about the new biochemical markers, to discuss some problems of diagnostic strategy in the early and exact detection of ischemic myocardial damage and to attract attention to the difficulties. However its disadvantage resides in its presence in both myocardium and skeletal muscles which arise when the diagnosis of acute myocardial infarction is prematurely excluded from consideration and such patients are discharged too soon from hospital. (Fig. 1, Tab. 1, Ref. 72.)     

Call to needle times after acute myocardial infarction in urban and rural areas in northeast Scotland: prospective observational study

OBJECTIVE: To determine call to needle times and consider how best to provide timely thrombolytic treatment for patients with acute myocardial infarction. DESIGN: Prospective observational study. SETTING: City, suburban, and country practices referring patients to a single district general hospital in northeast Scotland. SUBJECTS: 1046 patients with suspected acute myocardial infarction given thrombolytic treatment. MAIN OUTCOME MEASURES: Time from patients' calls for medical help until receipt of opiate or thrombolytic treatment, measured against a call to needle time of 90 minutes or less, as proposed by the British Heart Foundation. RESULTS: General practitioners were the first medical contact in 97% (528/544) of calls by country patients and 68% (340/502) of city and suburban patients. When opiate was given by general practitioners, median call to opiate time was about 30 minutes (95% within 90 minutes) in city, suburbs, and country; call to opiate delay was about 60 minutes in city and suburban patients calling "999" for an ambulance. One third of country patients received thrombolytic treatment from their general practitioners with a median call to thrombolysis time of 45 minutes (93% within 90 minutes); this compares with 150 minutes (5% within 90 minutes) when this treatment was deferred until after hospital admission. In the city and suburbs, no thrombolytic treatment was given outside hospital, and only a minority of patients received it within 90 minutes of calling; median call to thrombolysis time was 95 (46% within 90 minutes) minutes. CONCLUSIONS: The first medical contact after acute myocardial infarction is most commonly with a general practitioner. This contact provides the optimum opportunity to give thrombolytic treatment within the British Heart Foundation's guideline.     

Acute myocardial infarction: early recognition and management from the home healthcare nurses perspective

Acute myocardial infarction is the number one killer of men and women in the United States. Early recognition and treatment has been shown to decrease mortality and infarct size, and to improve left ventricular function. The home healthcare nurse is in a key position to perform a swift, pertinent assessment that can detect an acute myocardial infarction, provide the patient with the valuable information to decrease the time delay until thrombolytic therapy is initiated, participate in the rehabilitation post-myocardial infarction, and provide education and counseling for coronary heart disease risk reduction.     

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.     

Dietary-sodium-induced cardiac remodeling in spontaneously hypertensive rat versus Wistar-Kyoto rat

OBJECTIVE: To determine lengths and causes of pre- and in-hospital delays in thrombolytic treatment. DESIGN: A prospective national survey covering 48 of the 51 Finnish university, central and general hospitals to obtain basic data before the start of a public campaign to shorten patient-related delay in acute myocardial infarction. SUBJECTS: One thousand and twelve consecutive patients with acute myocardial infarction who received thrombolytic therapy over 3 months in 1995 and who represent 40% of all patients with confirmed acute myocardial infarction. RESULTS: The median interval between onset of infarction symptoms and initiation of thrombolytic therapy was 160 min (30-647). Only 13% of the patients received thrombolysis within 60 min and 38% within 120 min. The median time from the onset of symptoms to the call for help was 60 min (5-491), and no difference was found in patients with or without a history of previous myocardial infarction (60 and 64 min, respectively). Only 52% of the patients called to the dispatch centre. The median delay from calling for help to hospital arrival was 40 min (10-170). The median in-hospital door-to-needle thrombolysis delay was 40 min (12-196). In 13% of hospitals the median delay was more than 60 min. The emergency physician encountered difficulties in decision making in 33% of cases. CONCLUSIONS: Only 38% of the patient received thrombolysis within 2 h of onset of symptoms. Patient-related delay before they sought help accounted for the major portion of the total treatment delay. Thus the findings emphasize the importance of prompt action when people are confronted with an acute heart attack. Reorganizing the emergency medical service and emergency department routines is also a necessary target to shorten thrombolysis delays. The delay attributable to transporting patients could be shortened by initiating thrombolytic treatment in the pre-hospital setting. In Finnish hospitals, door-to-needle delay was acceptable in cases with clear indications for thrombolysis. However, emergency physicians often had diagnostic difficulties, which led to remarkably longer in-hospital delays.     

Primary angioplasty is elective reperfusion therapy in the treatment of acute myocardial infarction. Arguments in favor

Thrombolytic treatment has demonstrated its efficacy on acute myocardial infarction. However, it cannot be used in a significant number of patients and it doesn't achieve adequate reperfusion in a great percentage of cases. Primary angioplasty, a treatment which can be used in the majority of acute myocardial infarction patients, obtains artery patency in more than 90% of cases, with a better perfusion in the infarct territory and fewer reocclusion rates compared to thrombolysis. Consequently, primary angioplasty is associated with a lower mortality rate, and a lower incidence of recurrent ischemia and hemorrhagic stroke during hospitalization. Coronary artery stents and new antiplatelet agents have improved the short-term and mid-term results of primary angioplasty. Currently, when the facilities and trained personal are available, primary angioplasty should be the treatment of choice in acute myocardial infarction.     

The recent trend of coronary surgery

As the use of PTCA (Percutaneous Transluminal Coronary Angioplasty) is progressively widespread, the indication of CABG (Coronary Artery Bypass Grafting) and its candidates are changing accordingly. At present the candidates for CABG have left main trunk disease or severe triple-vessel disease, which are difficult or too dangerous to undergo PTCA. We should also note the population of operative candidates is becoming gradually older than before. The results from CABG appear to be limited according to the random follow-up studies in Europe and United States. The recurrence of angina and myocardial infarction tends to happen after five years. Our follow-up study shows the same tendency as those studies abroad. In order to improve the long-term results of CABG, we recommend the use of arterial grafts such as internal mammary artery, opt to the complete revascularization, and follow the patients postoperatively maximum medical therapy. At the same time, we should stress the importance of deciding the best operative opportunity, and not hesitate to make the decision for reoperation if it became necessary. Older candidates have tendency to suffer from neurological or respiratory complications during the postoperative period. If the risk of those complications appears great from the preoperative examination, we must make efforts to prevent those complications and finish CABG in the shortest possible time. Recently the cases for emergent CABG are decreasing for unstable angina or acute myocardial infarction, because PTCA is more effective for a short time. Time appears to be the most limiting factor for emergent coronary revascularization. Therefore the indication of emergent CABG is left only for left main trunk disease or severe triple vessel disease with complete occlusion of two coronary vessels. As a conclusion, CABG should be considered as only a palliative therapy same as PTCA and other medical treatments. Therefore the treatment of ischemic heart disease must be constituted by a integrated strategy including PTCA and drug therapy arranged for each patient.     

Aspirin and risk of hemorrhagic stroke: a meta-analysis of randomized controlled trials

CONTEXT: Aspirin has been widely used to prevent myocardial infarction and ischemic stroke but some studies have suggested it increases risk of hemorrhagic stroke. OBJECTIVE: To estimate the risk of hemorrhagic stroke associated with aspirin treatment. DATA SOURCES: Studies were retrieved using MEDLINE (search terms, aspirin, cerebrovascular disorders, and stroke), bibliographies of the articles retrieved, and the authors' reference files. STUDY SELECTION: All trials published in English-language journals before July 1997 in which participants were randomized to aspirin or a control treatment for at least 1 month and in which the incidence of stroke subtype was reported. DATA EXTRACTION: Information on country of origin, sample size, duration, study design, aspirin dosage, participant characteristics, and outcomes was abstracted independently by 2 authors who used a standardized protocol. DATA SYNTHESIS: Data from 16 trials with 55462 participants and 108 hemorrhagic stroke cases were analyzed. The mean dosage of aspirin was 273 mg/d and mean duration of treatment was 37 months. Aspirin use was associated with an absolute risk reduction in myocardial infarction of 137 events per 10000 persons (95% confidence interval [CI], 107-167; P<.001) and in ischemic stroke, a reduction of 39 events per 10000 persons (95% CI, 17-61; P<.001). However, aspirin treatment was also associated with an absolute risk increase in hemorrhagic stroke of 12 events per 10000 persons (95% CI, 5-20; P<.001). This risk did not differ by participant or study design characteristics. CONCLUSIONS: These results indicate that aspirin therapy increases the risk of hemorrhagic stroke. However, the overall benefit of aspirin use on myocardial infarction and ischemic stroke may outweigh its adverse effects on risk of hemorrhagic stroke in most populations.     

The need to quantify right-to-left shunt in acute ischemic stroke: a case-control study

BACKGROUND AND PURPOSE: Although right-to-left shunt (RLSh) has been reported to be significantly more frequent in young stroke patients with cryptogenic stroke, its relevance in a nonselected population of acute ischemic stroke is not well known. The aim of this study was to determine the importance of the RLSh magnitude as a risk factor for stroke in nonselected patients. METHODS: Two hundred eight patients hospitalized consecutively with transient ischemic attack or acute cerebral infarction and 100 healthy control subjects were studied. Transcranial Doppler ultrasonography (TCD) was performed in both middle cerebral arteries (MCAs) after intravenous application of agitated saline solution. The magnitude of RLSh was quantified by counting the number of signals in 1 MCA during a Valsalva maneuver. RLSh was classified as "no shunt," "small" (< 10 signals), and "large" (> 10 signals), with the latter including the "shower" (> 25 signals) and "curtain" (uncountable signals) patterns. Extensive investigations, including contrast transesophageal echocardiography, were carried out on patients diagnosed as suffering from stroke of an uncertain etiology. The importance of RLSh for stroke was assessed by logistic regression analysis. RESULTS: Contrast TCD detected a large RLSh in 40 (19.7%) patients and in 21 (21%) control subjects, all with cardiac RLSh characteristics. A large RLSh was present in 4.7% of atherothrombotic strokes, 10.5% of cardioembolic strokes, 15.4% of lacunar strokes, and 45.3% of cryptogenic strokes (P<0.001). Although the overall frequency of RLSh was not significantly different between patients and control subjects, the detection of curtain or shower patterns by contrast TCD was associated with a higher risk of stroke (odds ratio, 3.5; 95% confidence interval, 1.29 to 9.87), particularly with cryptogenic stroke (odds ratio, 12.4; 95% confidence interval, 4.08 to 38.09) after adjustment for concomitant vascular risk factors. CONCLUSIONS: It is essential to quantify RLSh by contrast TCD during the Valsalva maneuver given that only those with shower and curtain patterns are associated with a higher risk of ischemic stroke in a nonselected population.     

Symptomatic urinary tract infection in women in primary health care. Bacteriological, clinical and diagnostic aspects in relation to host response to infection

Myocardial infarctions which are derived from embolic source have an incidence of 5-13%. They are at risk of systemic embolism. The pathogenesis of myocardial infarction is similar to that of those myocardial infarction whose etiology is atherosclerosis. This make it susceptible to thrombolysis. We report 3 patients with either inactive rheumatic heart disease, coarctation of the aorta or mechanical valvular prosthesis as the probable causes of an embolic infarction. It was located in the posterior-inferior region with a dorsal extension. These patients were treated with intravenous streptokinase. The three of them fulfilled criteria for myocardial reperfusion. Two of them suffered post-infarction angina. In the first case reocclusion of the righ coronary artery was observed; thus a saphenous vein graft was undertaken. In the second, the persistence of thrombus required three month treatment with anticoagulants. The third patient showed not coronary lesions. In conclusion, thrombolytic therapy with streptokinase in acute infarction of embolic origin prevents the progression of ischemic damage and betters the clinical outcome of the patient. Furthermore such disease should be suspected in patients that have risk factors for systemic embolism and normal coronary arteries and with obstruction of a single vessel.     

Late thrombolysis in acute myocardial infarct: short and long term effects on left ventricular function

Although the efficacy of intravenous thrombolysis in the treatment of acute myocardial infarction has been widely proved, some uncertainty concerning the "temporal window" of administration still persists. The aim of the present investigation was to study whether the late administration of a thrombolytic agent (6 or more hours after the onset of symptoms of acute myocardial infarction) offers any short or long-term advantages with regards to left ventricular function and clinical outcome. We studied 100 consecutive patients at their first episode of myocardial infarction, admitted to Coronary Unit within 24 hours of the onset of symptoms. Of these patients, 62 were administered rt-PA (44 patients within the 6th hour, and 18 between the 6th and 24th hour after the onset of symptoms) and the 38 remaining patients, who did not receive the thrombolytic agent (due to concerns with respect to possible complications), constituted the control group (18 admitted within 6 hours and 20 between 6 and 24 hours). All patients underwent serial electrocardiograms, and echocardiograms upon admission and at discharge to assess the ejection fraction, the asynergy score and the percentage of ischemic area. Furthermore, the survivors were invited for a follow-up examination one year after their acute initial episode. Seven cases of heart failure occurred, before discharge, among the control patients admitted 6 to 24 hours after onset of symptoms, compared with no cases in the subgroup of patients treated with rt-PA during the same time period (p = 0.0068).(ABSTRACT TRUNCATED AT 250 WORDS)     

Electrophysiologic effects of quinaprilat in dogs during acute myocardial ischemia and following reperfusion

BACKGROUND: There have been few studies concerning the electrophysiologic changes associated with the use of angiotensin-converting enzyme inhibitors in patients with acute myocardial infarction. We examined the electrophysiologic effects of quinaprilat in dogs during acute myocardial ischemia and following reperfusion. METHODS: The left anterior descending coronary artery was occluded for 10 min and reperfused for 10 min. Animals received intravenous quinaprilat (3 micrograms/kg per min, quinaprilat group) or saline (control group). We measured the ventricular effective refractory period and intra-myocardial conduction time within the left anterior descending coronary artery region (ischemic region) during myocardial ischemia and following reperfusion, and determined the frequency of ventricular fibrillation. RESULTS: The effective refractory period in the ischemic region decreased during myocardial ischemia and decreased further immediately after reperfusion in the control group. The intra-myocardial conduction time in the ischemic region increased during myocardial ischemia but rapidly shortened after reperfusion in the control group. In the quinaprilat group, however, no significant differences were evident between the ischemic and non-ischemic regions in either the effective refractory period or the intra-myocardial conduction time during myocardial ischemia or following reperfusion. The percentage shortening of the effective refractory period and the percentage prolongation of the intra-myocardial conduction time in the ischemic region were significantly lower in the quinaprilat group than in the control group during myocardial ischemia and following reperfusion. The frequency of ventricular fibrillation during myocardial ischemia and following reperfusion was significantly lower in the quinaprilat group (21%) than in the control group (74%; P < 0.01). CONCLUSIONS: Quinaprilat protects against electrophysiologic abnormalities, and may decrease arrhythmias during acute myocardial ischemia and following reperfusion.     

The relationship between argyrophilic proteins and some immunophenotypic markers in acute leukemia cells

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.