Completed Stroke Research Articles

Three-Dimensional Analysis of the Men‘s 100-m Freestyle during the 1992 Olympic Games

Twelve male 100-m freestyle swimmers were videotaped during the 1992 Olympic Games. Four cameras, two above water and two below, recorded the same stroke cycle of the swimmer at approximately the 40- to 45-m mark. The whole body and the recovering arms were digitized from the videotapes to recreate a complete stroke cycle. Body position variables and hand reaction forces (Schleihauf, 1979) were calculated. Swimmers were divided into elite and subelite groups based on their swimming velocity and were compared for differences in biomechanical variables. Elites used slightly lower hand forces while maintaining a higher propelling efficiency. Subelites had opposite rotations about the longitudinal axis of the body rather than symmetrical body roll. The elite swimmers were different from subelites in that their pulling patterns were more efficient and their body position was more streamlined. These variables assisted them in achieving faster swimming velocities without requiring higher propulsive forces.

Physician attitudes toward treatment options for cerebrovascular disease

One-hundred physicians older than 50 and 100 physicians younger than 50 were surveyed concerning treatment preferences for patients with transient ischemic attacks (TIAs) or completed stroke. These attitudes were compared to cardiovascular disease prevention strategies for patients with angina pectoris and myocardial infarction. Physicians younger than 50 were therapeutically aggressive for cerebrovascular and cardiovascular disease; physicians older than 50 were aggressive for cardiovascular disease but therapeutically nihilistic for cerebrovascular disease. Physicians younger than 50 were more likely to be aggressive for TIA than for completed stroke patients, and these physicians were more likely to utilize ticlopidine and oral anticoagulants for both TIA and completed stroke patients.

Prevalence of Neurological Disorders in Haute-Vienne Department (Limousin Region – France)

The Limousin region had at present one of the largest elderly populations in France and in Europe. To determine the frequency of certain neurological disorders in the elderly, a neuroepidemiological survey was conducted in 1986-1987 on a representative sample of the population in Haute-Vienne (the most population-dense department in the Limousin region). This study used a WHO protocol which was first introduced at the beginning of the 1980s. It had been previously tested in France on a pilot population in 1984. The prevalences of the principal neurological disorders encountered per 100,000 inhabitants were as follows: nonmigraine headache 5,059, migraine 4,270, epilepsy 788, completed stroke 1,445, transient ischemic attacks 657, neuropathy 1,642, Parkinson's disease 328, and dementia 197.

Successful Treatment of an Acute Thrombosis of an Intracranial Vertebral Artery Endarterectomy with Urokinase

THIS IS A case report of a 47-year-old man admitted with a 7-month history of disequilibrium, multiple reversible vertebrobasilar ischemic attacks, and one submaximal completed stroke in the left posterior inferior cerebellar artery distribution. Vertebrobasilar ischemic attacks continued despite anticoagulation, and orthostatic symptomatology suggested a significant hemodynamic component contributing to the posterior circulation ischemia. Angiography confirmed bilateral high-grade stenoses of the intracranial vertebral arteries. A right intracranial vertebral artery endarterectomy was performed with electroencephalographic and somatosensory evoked potential monitoring and protection with barbiturate infusion. The arteriotomy was closed with a vein patch. Postoperatively, the endarterectomy site thrombosed. This thrombosis was completely reversed with 220,000 U of urokinase selectively infused intra-arterially at the site of thrombosis. This procedure was not complicated by hemorrhage or distal embolization. The vertebral artery was confirmed to be patent 24 hours and 7 days after the urokinase injection. The patient sustained a borderzone infarction in the right cerebellar hemisphere without neurological deficits and was discharged home well.

Consultant views on the use of aspirin in acute cerebrovascular disease: implications for clinical trials

A questionnaire was sent to all 155 consultant physicians and geriatricians in the Yorkshire region who routinely admit patients with acute stroke in order to ascertain: (a) current opinion regarding the prescription of aspirin to patients with various manifestations of cerebrovascular disease, in particular the timing of initial treatment; and (b) the perceived role of computed tomography (CT) scans in relation to such therapy. The response rate was 81% (126/155). Aspirin was reported to be prescribed routinely by 75% (95/126) of physicians for patients with completed stroke. Amongst those prescribing aspirin, treatment was reported to be initiated routinely within 48 hours of the onset of symptoms by 63% (60/95). Only 10% (6/60) of these physicians reported that they would withhold aspirin therapy until the result of a cranial CT scan was known, although 43% (26/60) thought a CT scan was desirable. Our survey, which for logistical reasons is one of opinion rather than actual practice, suggests that aspirin is probably being prescribed acutely (less than 48 hours) after stroke to a significant number of patients and often without a pretreatment CT scan. As with patients who have had a CT scan, the balance of risks and benefits of this practice are unknown. We conclude that it would be ethical for acute treatment trials to allow randomization to aspirin without prior CT scan.

Silent cerebral infarcts in patients with ischemic infarction

Silent cerebral infarcts occur in patients with chronic nonvalvular atrial fibrillation and asymptomatic or symptomatic carotid stenosis. There is not a well-defined prevalence of asymptomatic lesions in patients with transient ischemic attack or completed strokes. We attempted to determine the occurrence rate of silent brain infarction in a hospital population, including a comparison of the risk factors with those of symptomatic infarction and an evaluation of the relevance of infarction size and location.

The semantics of brain hemorrhage: Some practical problems of risk and benefit assessment in fibrinolytic therapy

Undoubtedly, the most exciting development in stroke treatment in many years is the potential application of fibrinolytic drugs to the first few hours after the onset of acute cerebral ischemia. Given in the window of opportunity between the abrupt loss of function (functio laessa), concomitant with the biochemical and metabolic disorder (inadequate blood supply), and the onset of irreversible anatomical changes (tumor, dolor, calor, rubor, etc.), nicely visualized today by a number of transcranial imaging methods, rt-PA and other proven fibrinolytic agents offer the best chance yet for the secondary prevention of thromboembolic strokes, that is, the prevention of permanent functional impairment from an extant disease state that began long before the patient sought medical intervention. Early reports of scientific feasibility in animal models (1,2) and recent reports of open-label (3,4) and controlled clinical trials are encouraging (5). Reports of hemorrhagic complications of these drugs, both in heart patients (6,7) and in those with strokes (3-5,8), are worrisome. Although struggling to prove the efficacy of tPA in acute completed stroke, simultaneously taking into account the natural history of strokes due to thrombosis, cerebral embolism, transient ischemic attacks (TlAs) and stroke-in-evolution, we must also evaluate the spontaneous hemorrhagic complication rates in each of these events, in order to establish a true risk/ benefit ratio of early fibrinolysis. Therefore, a number of controlled clinical trials are in progress. These studies exclude most of the patients who present with known risk factors for spontaneous hemorrhages and

Antiplatelet therapy in the treatment of cerebrovascular disease.

Aspirin and the new agent ticlopidine have been the most thoroughly evaluated of the platelet-antiaggregating drugs used for the prevention of stroke and other vascular events. Numerous trials have shown aspirin to be effective in reducing the risk of myocardial infarction (MI), recurrent transient ischemic attacks, stroke, and vascular death in men at high risk for these events. Primary prevention trials have shown that aspirin reduces the risk of MI in healthy men over 50 years of age but does not reduce the risk of stroke. Two large, multicenter trials have shown that ticlopidine is effective in reducing the risk of fatal and nonfatal stroke in both men and women. Ticlopidine may also be effective in reducing the risk of recurrent stroke in patients who have had a completed thromboembolic stroke.

Secular trends in stroke in the Framingham study

Trends in stroke incidence, prevalence, fatality, and severity were examined in Framingham Study subjects, aged 55 to 64, during 3 successive decades beginning in 1953, 1963, and 1973. There was no significant decline in incidence or prevalence of total stroke and transient ischemic attacks (TIAs). In women, but not men, incidence of completed ischemic stroke declined significantly. Stroke severity did decrease significantly and severe neurologic deficit was less frequent in later decades; fewer patients with stroke were unconscious on admission to the hospital. There was no substantial change in the case mix and no significant decline in hemorrhage to account for the decline in severity. The proportion of isolated TIAs increased significantly over the 30 years studied, yielding an apparent decline in case-fatality rates, which was significant only in men. Secular trends in stroke incidence and fatality did not follow a clear pattern. There was a significant decline in stroke severity, but incidence of infarction fell only in women. The decline in total case-fatality rate occurred only in men, resulting largely from an increased incidence of isolated TIAs.

Changes in bone mineral content and density after stroke.

The purpose of this study was to determine whether there are differences in bone mineral content and density between paralyzed and nonparalyzed sides of patients who had sustained strokes associated with unilateral muscle weakness, to determine the relationship between duration of stroke and degree of demineralization and to compare the degree of demineralization in upper and lower limbs. The bone mineral content and density were measured by dual photon absorptiometry (high resolution scanning mode, Lunar DP4) in ambulant patients with a history of single completed strokes associated with unilateral weakness. The bone mineral content and density of each limb was determined by the region of interest analysis program. In the 30 patients included in this study, the bone mineral content and density were significantly less on the paralyzed than on the nonparalyzed side. The degree of demineralization was more pronounced in the upper than in the lower limbs. The mean percentage differences in bone mineral content and density between paralyzed and nonparalyzed arms were 13.8% (P < 0.00001) and 7.95% (P = 0.0003), respectively, and between paralyzed and nonparalyzed legs the differences were 4.5% (P = 0.0012) and 3.42% (P = 0.0028), respectively. A better correlation was noted between the time elapsed since the stroke and the degree of demineralization in the upper limbs (r = 0.75, P < 0.0001), than in the lower limbs (r = 0.60, P = 0.0004). In conclusion, patients who have strokes associated with muscle weakness are at an increased risk of developing osteoporosis on the paralyzed side and particularly in the upper limbs.

Cardiopulmonary bypass in patients with previously completed stroke

It has been assumed that patients with neurological residua after a completed stroke are at increased risk of neurological complications associated with cardiac operations requiring cardiopulmonary bypass. To evaluate these assumptions, we reviewed retrospectively 1,163 consecutive patients undergoing cardiac operations with cardiopulmonary bypass. Among these 1,163 patients were 43 patients having a previously completed stroke with neurological residua, but without clinically significant extracranial carotid artery disease. Forty-one underwent coronary artery bypass grafting; of these, 1 required concomitant aortic valve replacement, 1 had mitral valve replacement, and 1 had aortic valve replacement. There was one death in this group of 43 patients, due to massive pulmonary embolism. Only 1 of these 43 patients experienced new neurological symptoms after operation, which would appear to indicate that patients with a previous, completed stroke may not be at increased risk of neurological complications from cardiac operations requiring cardiopulmonary bypass.

Surgical reconstruction of failed indirect anastomosis in childhood Moyamoya disease.

Thirty-one patients with moyamoya disease, who had been treated for encephaloduroarteriosynangiosis (EDAS), encephalomyosynangiosis (EMS) or EMS with encephaloarteriosynangiosis (EAS) in other hospitals, were admitted to Osaka Neurological Institute from January 1985 to September 1991. Twenty-seven of 57 sides treated by indirect anastomosis showed good filling of the middle cerebral artery (MCA) territory via the anastomosis, whereas 16 and 14 showed fair and poor collaterals via the anastomosis, respectively. Twenty-eight cerebral hemispheres treated by indirect anastomosis underwent further surgery and received superficial temporal artery-MCA anastomosis with or without EMS for still-existent recurrent transient ischemic attacks or completed stroke even after the indirect anastomosis. One patient still had recurrent transient ischemic attacks with quadriparesis after bilateral encephaloduroarteriosynangiosis, which had produced no effective collaterals in the MCA territory; the patient then underwent omental transplantation to the bilateral anterior cerebral artery and MCA territories, resulting in the cessation of the transient ischemic attacks. Clinical improvement after superficial temporal artery-MCA anastomosis with or without EMS was noted in all patients, except on one side, where a completed stroke had resulted in fixed neurological deficits. We do not know the reasons for the uncertainty of the development of collaterals via the indirect anastomosis, but there are many patients who still need direct reconstruction of the indirect anastomosis.

Acetazolamide test in detecting reduced cerebral perfusion reserve and predicting long-term prognosis in patients with internal carotid artery occlusion.

In a series of 32 patients with internal carotid artery occlusion, regional cerebral blood flow (rCBF) and regional cerebral vasoreactivity (rCVR) were measured by xenon-133 single photon emission computed tomography and the acetazolamide test. We evaluated its usefulness in detecting the reduced cerebral perfusion reserve and predicting long-term prognosis. All Type 1 patients (normal rCBF and rCVR) were medically treated and experienced no recurrent ischemic attack. Cerebral hemodynamics remained unchanged. Type 2, 3, and 4 patients underwent superficial temporal artery-middle cerebral artery double anastomosis, if they consented to surgery. All Type 2 (normal rCBF and reduced rCVR) and Type 3 (reduced rCBF and rCVR) patients, who underwent surgery, showed no further ischemic attacks, as well as long-term normalization of rCVR, although long-term rCBF normalization was obtained in only three of seven Type 3 patients. Cerebral hemodynamics remained unchanged in Type 4 patients after surgery. In follow-up periods, major completed stroke occurred in all 3 Type 2 and Type 3 patients who were medically treated. These results suggest that the acetazolamide test is valuable in assessing the cerebral perfusion reserve and predicting long-term prognosis in patients with internal carotid artery occlusion, although further long-term or randomized studies are needed.

Risk of stroke in adults with cyanotic congenital heart disease.

Adults with cyanotic congenital heart disease and elevated hematocrit levels are often phlebotomized because of an assumed risk of cerebral arterial thrombotic stroke. Whether a relation exists between hematocrit level, symptomatic erythrocytosis (hyperviscosity), and stroke remains to be established in this patient population. Accordingly, 112 cyanotic patients 19-74 years old (mean, 36 +/- 11.7 years) in the UCLA Adult Congenital Heart Disease Center Registry were selected for study by virtue of continuous observation for 1-12 years (total, 748 patient-years). Patients with independent risk factors for embolic or vasospastic stroke were excluded. The study patients were then divided into two groups: 1) compensated erythrocytosis (stable hematocrit levels of 46.0-72.7% [mean, 57.5 +/- 7.2%], iron replete, absent or mild hyperviscosity symptoms), and 2) decompensated erythrocytosis (unstable rising hematocrit levels of 61.5-75.0% [mean, 69.5 +/- 10.6%], iron deficiency, marked-to-severe hyperviscosity symptoms). No patient with either compensated or decompensated erythrocytosis, irrespective of hematocrit level, iron stores, or the presence, degree, or recurrence of cerebral hyperviscosity symptoms, progressed to clinical evidence of a complete stroke (cerebral arterial thrombosis with brain infarction). Because a risk of stroke caused by cerebral arterial thrombosis was not demonstrated, because the circulatory effects of phlebotomy are transient, and because of the untoward sequelae of phlebotomy-induced iron deficiency, we recommend phlebotomy for the temporary relief of significant, intrusive hyperviscosity symptoms but not for the hematocrit level per se. According to our data, phlebotomy is not warranted to reduce an assumed risk of stroke because that risk did not materialize.

Prophylaxis and treatment of stroke. The state of the art in 1993.

The most significant impact on cerebral infarction comes from the primary prevention of the processes that lead to stroke in at-risk individuals prior to the development of symptoms. Antithrombotic therapy with warfarin or aspirin significantly reduces thromboembolic risk in non-valvular atrial fibrillation. The failure of primary preventive measures and the progression of disease is heralded by the development of cerebral or retinal ischaemic events; the majority of clinical trials investigating stroke prevention have targeted the secondary prevention of stroke in patients with ischaemic symptoms. A 25% risk reduction has been demonstrated with antiplatelet therapy. This was typically aspirin 1000 to 1300 mg/day, but more recently even lower doses have been beneficial, with lower rates of minor and major bleeding. Ticlopidine has demonstrated efficacy in the secondary prevention of stroke after transient ischaemic attacks and completed stroke, with a 2% risk of significant neutropenia. The benefits of carotid endarterectomy have been demonstrated in patients with symptomatic internal carotid artery stenosis involving 70 to 99% of the arterial diameter. Surgery is not indicated in patients with less than 30% internal carotid artery stenosis; 30 to 69% continues to be studied. When primary and secondary preventive measures have failed, strategies directed at managing acute focal cerebral ischaemia include re-establishing cerebral blood flow and limiting ischaemic neuronal injury. Advances in basic research that have identified components of the ischaemic cascade have been translated clinically into numerous clinical trials, each targeted to one or sometimes two steps in the hope of improving neuronal salvage.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of superficial temporal to middle cerebral artery anastomosis against hemodynamic stroke.

The effect of superficial temporal artery-middle cerebral artery anastomosis on regional cerebral blood flow (rCBF) was measured on 31 patients with ischemic cerebrovascular diseases. rCBF was measured on the precentral and superior temporal gyri during surgery using the thermal diffusion technique. The mean rCBF was significantly lower than controls before anastomosis, but increased significantly after. Severer clinical symptoms were associated with lower rCBF. The rCBF increased significantly in patients with transient ischemic attack, reversible ischemic neurological deficit, and minor and major completed stroke. All 31 patients demonstrated dysautoregulation, both before and after anastomosis. However, the rCBF had increased above the ischemic threshold during hypotension, achieving a reserve capacity to prevent hemodynamic stroke.

Secular trends in stroke incidence and mortality. The Framingham Study.

The reduction in US stroke mortality has been attributed to declining stroke incidence. However, evidence is accumulating of a trend in declining stroke severity. We examined secular trends in stroke incidence, prevalence, and fatality in Framingham Study subjects aged 55-64 years in three successive decades beginning in 1953, 1963, and 1973. No significant decline in overall stroke and transient ischemic attack incidence or prevalence occurred. In women, but not men, incidence of completed ischemic stroke declined significantly. Stroke severity, however, decreased significantly over time. Stroke with severe neurological deficit decreased in later decades, with a fall in rates of severe stroke cases in which patients were unconscious on admission to the hospital. There was no substantial change in the case mix of infarcts and hemorrhages and no decline in hemorrhage to account for the decline in severity. The proportion of isolated transient ischemic attacks increased significantly over the 30 years studied, yielding an apparent and significant decline in case-fatality rates in men only. Secular trends in stroke incidence and fatality did not follow a clear or definite pattern of decline. While a significant decline in stroke severity occurred over three decades, incidence of infarction fell only in women. The decline in total case fatality rates occurred only in men and resulted largely from an increased incidence of isolated transient ischemic attacks. The severity of completed stroke was significantly lower in the later decades under study.

Long-term follow-up study after extracranial-intracranial bypass surgery for anterior circulation ischemia in childhood moyamoya disease.

Between May, 1974, and March, 1991, 104 patients with moyamoya disease, all under 16 years old at the time of first surgery, underwent superficial temporal-to-middle cerebral artery anastomosis and/or encephalomyosynangiosis. The mean follow-up period was 9.6 years (range 4.8 to 16.0 years). Hemiplegia was the most frequent symptom before the first operation. Transient ischemic attacks (TIA's) were noted in 57 patients and minor stroke with hemiplegia in 44. The most frequent type of cortical dysfunction was aphasia (21 cases). Postoperatively, the incidence of TIA's and/or completed stroke with motor weakness of the extremities was markedly decreased, but visual disturbance progressed and major or minor stroke with visual disturbance was found in two cases. In patients under the age of 3 years, a major stroke prior to surgery resulted in a poor outcome in 36% of cases. Preoperative major stroke in patients between the ages of 3 and 7 years was less frequent, and poor outcomes were seen in 17% of this group. There were no major preoperative strokes in patients with surgery after the age of 7 years, and no poor outcomes were recorded in this group. A major preoperative stroke prior to surgery had adverse impact on the ultimate patient intelligence quotient (IQ) following surgery. All patients operated on after the age of 7 years had a normal or borderline IQ at follow-up examination.

A Critical Appraisal of Ticlopidine, a New Antiplatelet Agent

Recommendations are broadening for the prophylaxis of atherosclerotic disorders, but aspirin is the only widely used agent. Ticlopidine hydrochloride, a new antiplatelet medication, has recently been approved for prescription in North America. We reviewed the major clinical trials of ticlopidine and derived guidelines for its use. Studies of ticlopidine were sought through MEDLINE for 1980 to 1990 and through bibliographies of retrieved articles. All published, randomized trials of ticlopidine were appraised if they reported major morbidity and mortality as primary end points. All eligible studies were formally reviewed by an expert panel according to published principles for critical appraisal of the medical literature. Both benefits and risks were quantified. Four randomized trials reported major clinical end points. In these, ticlopidine was more effective than placebo for preventing recurrences after completed stroke; was more effective than aspirin for patients with transient ischemic attacks and partial strokes; and reduced vascular death and nonfatal myocardial infarction in an open trial among patients with unstable angina. For patients with intermittent claudication ticlopidine, was not significantly better than placebo for preventing myocardial infarction or stroke. Side effects were more common with ticlopidine than with aspirin or placebo. Ticlopidine should be prescribed in place of aspirin for stroke prophylaxis or unstable angina if the patient is unable to tolerate aspirin. Ticlopidine may also benefit patients who experience new ischemic events while taking aspirin or, probably, patients with peripheral vascular disease. A complete blood cell count should be performed every 2 weeks during the first 3 months of therapy to check for leukopenia.

Vergleich des EEG-Mapping mit und ohne visuelle Artefakt-Kontrolle bei fokalen zerebralen Läsionen

In 163 patients with focal cerebral lesions, 43 of them with completed stroke, 43 patients with TIA, 33 patients with ICH and 29 patients with malignant and 15 patients with benign tumors EEG mapping and CT was performed. The results of EEG mapping obtained using automated artifact detection were compared to those achieved by means of visual control of raw EEG. Furthermore the impact of long (850 ± 250 s) or short (32 s) analysis time was studied. Eliminating artifacts by means of visual control of raw EEG significantly more positive results were obtained than using automated artifact detection. That was found in patients with as well as in patients without lesions in CT.