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ABSTRACT: BACKGROUND: Many patients with stroke-mimicking conditions receive treatment with intravenous fibrinolysis (IVF), a treatment associated with potentially serious complications. We sought to determine if any clinical or radiographic characteristics can help predict stroke mimics among IVF candidates. METHODS: This retrospective study was carried out at a single institution. Patients treated with intravenous recombinant tissue plasminogen activator (rt-PA; n = 193) were divided into 3 categories: acute ischemic stroke (n = 142), aborted stroke (n = 21), and stroke mimics (n = 30). Analysis of variance and the chi-square test were used to assess differences, while logistic regression models were computed to predict groups. RESULTS: Mimics treated with rt-PA did not experience complications (intracranial bleeding, systemic hemorrhage, or angioedema), and had better neurologic and functional outcomes than stroke patients (P < .05). Several variables helped differentiate strokes from mimics, including atherosclerosis on computed tomographic angiography (odds ratio [OR] 23.6; 95% confidence interval [CI] 8.4-66.2), atrial fibrillation (OR 11.4; 95% CI 1.5-86.3), age >50 years (OR 7.2; 95% CI 2.8-18.5), and focal weakness (OR 4.15; 95% CI 1.75-9.8). Other variables decreased chances of stroke: migraine history (OR 0.05; 95% CI 0.01-0.4), epilepsy (OR 0.13; 95% CI 0.02-0.8), paresthesia (OR 0.1; 95% CI 0.04-0.3), and precordialgia (OR 0.045; 95% CI 0.002-0.9). A regression model using focal weakness, computed tomographic angiography findings, and precordialgia had a 90.2% predictive accuracy. CONCLUSIONS: IVF has low complication rates in stroke mimics. Certain clinical characteristics appear predictive of stroke mimics, particularly normal computed tomographic angiography. If confirmed, this may help prevent giving IVF to patients without stroke.
Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 06/2011;
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Lucas Restrepo
Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital 02/2007; 34(2):259. · 0.65 Impact Factor
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ABSTRACT: Hunter syndrome, or mucopolysaccharidosis type II, is an X-linked recessive disorder resulting from iduronate sulfatase deficiency. Typical manifestations include short stature, mental retardation, hydrocephalus, macroglossia and cardiac valvulopathy. We describe a 21-year-old patient who presented with acute ischemic stroke and evidence of cerebral embolization. The echocardiogram demonstrated thickened mitral and aortic valves as potential sources of emboli. We conclude that ischemic stroke secondary to cardioembolization is a potential complication of Hunter syndrome.
Journal of Clinical Neuroscience 01/2007; 13(10):1054-7. · 1.25 Impact Factor
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ABSTRACT: Abnormalities in diffusion-weighted (DWI) and perfusion-weighted (PWI) magnetic resonance imaging (MRI) are thought to reflect the presence of brain tissue at risk for ischemic stroke. Many patients with acute ischemic stroke have a mismatch pattern in which the PWI volume is larger than the DWI lesion. This mismatch typically resolves over 24-48 hours. Little is known about the presence of DWI-PWI mismatch in later stages of stroke.
This is a retrospective study of 122 patients admitted with a diagnosis of acute ischemic stroke who had DWI and PWI abnormalities on studies performed within 7 days of onset of symptoms. Patients were divided into two groups: those with MRI performed <48 hours and those with MRI performed >or=48 hours from onset of symptoms.
Among 42 patients with MRI performed >or=48 hours after onset of stroke symptoms, 15 of 42 (36%) showed a mismatch pattern, compared to 45 of 80 (56%) in the <48 hours group (P < 0.05). Most of the patients in the >or=48 hours group with mismatch had large artery occlusive disease and many had neurological fluctuations. A subset of these patients were treated with induced hypertension and showed clinical improvement.
Some patients have persistent DWI-PWI mismatch up to several days after stroke onset. Further studies are needed to determine if these patients should be candidates for reperfusion therapy.
Journal of Neuroimaging 11/2006; 16(4):329-33. · 1.51 Impact Factor
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ABSTRACT: The management of blood pressure in acute stroke is controversial. Small pilot studies have suggested that blood pressure augmentation improves short-term neurological function, but the rate of adverse events with induced hypertension (IH) therapy is unknown.
We reviewed 100 consecutive patients who underwent perfusion magnetic resonance imaging for acute ischemic stroke. IH therapy was employed in 46 patients and standard therapy (ST) in 54. The two groups had similar baseline characteristics, but more patients in the IH group had significant large-artery stenoses. The IH group achieved significantly higher mean arterial pressure (MAP) than the ST group within 3 days of initiation of therapy with a variety of vasopressor agents. Only 35% of patients in the IH group actually achieved the target MAP augmentation of 10-20% above baseline, however. All patients survived to discharge. Four patients experienced major adverse events in each group. Two patients in the IH group experienced intra cerebral hemorrhage compared to none in the ST group. Two patients in the ST group experienced myocardial ischemia, compared to none in the IH group. The National Institutes of Health Stroke Scale during the hospitalization and place of discharge were similar in both groups. Patients in the IH group were more likely to be admitted to the intensive care unit and had a longer hospital stay by nearly 4 days compared to the ST group.
These data demonstrate the relative safety of IH therapy in acute stroke patients. Given the greater use of resources, however, the role of IH in improving clinical outcomes requires a prospective, randomized trial.
Neurocritical Care 02/2006; 4(1):3-7. · 2.47 Impact Factor
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ABSTRACT: Acute anterior spinal cord ischemia is a rare but disastrous complication of endovascular aortic procedures. Although intravenous thrombolysis with recombinant tissue plasminogen activator is an effective treatment for acute brain ischemia, its use for the treatment of spinal cord ischemia has not previously been reported. We report the case of a patient who developed anterior spinal cord ischemia during diagnostic aortography He was treated with intravenous recombinant tissue plasminogen activator within 3 hours after the onset of symptoms. The patient had a rapid neurologic improvement and was discharged from the hospital 3 days after thrombolysis, regaining his ability to walk unassisted. We propose that acute spinal cord ischemia can be treated with intravenous recombinant tissue plasminogen activator within 3 hours after the onset of symptoms, as can any other case of acute ischemic stroke.
Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital 02/2006; 33(1):74-7. · 0.65 Impact Factor
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ABSTRACT: Diffusion-and perfusion-weighted magnetic resonance imaging (DWI and PWI) are useful tools for the assessment of brain ischemia. Discrepancies between the extent of DWI and PWI abnormalities are thought to depend pre dominantly on time from symptom onset to magnetic resonance imaging (MRI) examination. However, underlying ischemic stroke etiology can also be important. A mismatch may indicate the presence of tissue at risk for infarction, whereas the relevance of other DWI/PWI patterns is uncertain. The authors therefore investigated the etiology of brain ischemia in patients with different DWI/PWI patterns.
Retrospective study of 130 patients with acute brain ischemia and detailed stroke workup, including MRI within a week after symptom onset (40 +/- 39 hours). Patients were divided into the following groups: mis-match (PWI > DWI), reverse mismatch (DWI > PWI), and match (<25% difference between PWI and DWI).
Mismatch occurred in 49% of patients, whereas 22% had reverse mis-match and 29% matched lesions. Time from symptom onset to MRI examination was similar between the 3 groups. Largeartery atherosclerosis increased by almost 4-fold the odds of mismatch (odds ratio: 3.89, 95% confidence interval: 1.72-8.78; P < .001), whereas patients with reverse mismatch were likely to have cryptogenic stroke. Patients with matched lesions were similarly distributed among different stroke subtypes.
Ischemic stroke etiology appears to influence the development of specific DWI/PWI patterns. Prospective studies are needed to confirm these observations.
Journal of Neuroimaging 07/2005; 15(3):254-60. · 1.51 Impact Factor
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ABSTRACT: The so-called rubral tremor is a clinical diagnosis that involves involuntary shaking limb movements during rest and voluntary motion. We report the cases of 2 patients who developed rubral tremor after cardiac catheterization. To our knowledge, this is the 1st report of such an association. In each case, brain magnetic resonance imaging revealed nothing unusual. The onset of tremor after cardiac catheterization may signal the presence of a complex neurologic syndrome, which warrants consultation with a neurologist.
Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital 02/2005; 32(3):427-9. · 0.65 Impact Factor
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ABSTRACT: A variety of fluent and nonfluent aphasias have been reported after left basal ganglia stroke. It has been speculated that this heterogeneity may reflect variations in cortical hypoperfusion resulting from large vessel stenosis. To test this hypothesis, a consecutive series of 24 patients with left caudate infarct identified with diffusion-weighted imaging underwent language testing and perfusion-weighted imaging < 24h from onset of symptoms. Specific regions in perisylvian cortex were rated for the percentage of the region that was hypoperfused. Aphasia type was determined on the basis of speech fluency, comprehension, and repetition performance on the language tests. Association between aphasia type/language impairment and regions of hypoperfusion were identified with Fisher's exact tests. Results demonstrated that in patients with acute left caudate infarct, the presence and type of aphasia reflected regions of hypoperfusion, and generally followed predictions based on chronic lesion studies, regarding anatomical lesions associated with classic aphasia types.
Brain and Language 07/2004; 89(3):524-30. · 3.12 Impact Factor
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ABSTRACT: Management of arterial dissections can be particularly challenging. We report a case of vertebral artery dissection in which perfusion- and diffusion-weighted MR imaging findings suggested the presence of salvageable tissue, despite that the patient had symptoms for more than 40 hours. Direct access to the distal vascular territory was unattainable, and the presence of collateral circulation through an occipital vertebral anastomosis provided the only pathway to administer intraarterial thrombolysis. This case demonstrates that perfusion- and diffusion-weighted MR imaging can be instrumental in the selection of candidates for aggressive stroke therapy. Arterial anastomoses can provide alternate access to ischemic vascular beds and merit careful evaluation during intraarterial thrombolysis.
American Journal of Neuroradiology 11/2003; 24(9):1823-6. · 2.93 Impact Factor
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ABSTRACT: Control of hypertension is a well-established goal of the primary and secondary prevention of stroke. However, management of blood pressure in the setting of acute brain ischemia is complicated by the possible effect of blood pressure changes on cerebral perfusion. In acute stroke, patients may have an ischemic penumbra of brain tissue, which has impaired perfusion but which is not irreversibly damaged. The ischemic penumbra may be salvaged with reperfusion. Lowering of blood pressure in this setting, however, would hasten the progression of the penumbra to infarction. With the exception of patients treated with thrombolytic agents, blood pressure reduction is not recommended in acute ischemic stroke for this reason. Preliminary studies suggest that there may be a role for interventions to elevate blood pressure as a treatment for acute stroke patients. Despite interest in induced hypertension as a treatment of stroke dating back to the 1950s, this practice has not achieved widespread use owing to concerns about potential adverse effects such as intracerebral hemorrhage, cerebral edema, and myocardial ischemia. It is commonly used, however, to treat patients with threatened cerebral ischemia due to vasospasm after subarachnoid hemorrhage. Until future studies clarify the effectiveness of induced hypertension in stroke treatment, maintaining adequate blood pressure and fluid volume is recommended for patients with acute ischemic stroke, particularly if the neurologic deficits are fluctuating or the patient has persistent large-vessel occlusive disease.
Current Treatment Options in Cardiovascular Medicine 08/2003; 5(3):193-199.
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ABSTRACT: Coronary artery bypass grafting (CABG) is a frequently performed surgical procedure that can be associated with neurological complications. Some studies have demonstrated that new focal brain lesions, detected by MRI, can develop after CABG. Furthermore, it has been suggested that the presence of such new lesions is associated with a decline in neurocognitive test scores. Advanced MRI techniques, including diffusion- (DWI) and perfusion-weighted imaging (PWI), offer important diagnostic advantages over conventional imaging in the assessment of patients undergoing CABG. We sought to determine whether focal PWI and DWI abnormalities could occur after CABG, particularly in patients without any measurable neurological deterioration.
Thirteen patients prospectively underwent MRI with DWI and PWI before and after CABG. A battery of neurocognitive tests was administered before and after surgery. Demographic, clinical, and radiographic characteristics of the patients were collected and compared.
Four patients developed new DWI defects after CABG. The lesions were small, rounded, and multiple (3 of 4 patients). One of these patients was diagnosed with stroke on clinical grounds. The patients with new lesions had a larger neurocognitive decline than their counterparts with stable MRI. Other clinical characteristics of patients with new DWI lesions, including stroke risk factors, were similar to those of patients without MRI changes. No focal perfusion abnormalities were observed on preoperative or postoperative scans.
Postoperative DWI abnormalities can occur after CABG, even in patients without overt neurological defects. The PWI scans remained unchanged. Larger prospective studies are required to determine whether the new lesions are clearly associated with neurocognitive decline or with specific perioperative stroke risk factors.
Stroke 01/2003; 33(12):2909-15. · 5.73 Impact Factor
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ABSTRACT: During the evaluation of acute ischemic stroke with diffusion- and perfusion-weighted magnetic resonance imaging (DWI and PWI, respectively), the presence of salvageable brain tissue is suggested by the occurrence of a perfusion-diffusion "mismatch." DWI and PWI, however, are not universally available and have inherent inconveniences, which justify a search for practical diagnostic alternatives. The purpose of this study is to investigate whether there are transcranial Doppler (TCD) markers of mismatch.
Retrospective analysis of 22 patients with acute ischemic stroke affecting the middle cerebral artery (MCA) territory, who had a TCD performed within 24 hours of magnetic resonance imaging (MRI) with DWI and PWI.
MRI and TCD were performed on average 10.8 +/- 9.2 hours apart. Time from symptom onset to MRI and TCD completion were 1.6 +/- 1.6 and 2 +/- 1.9 days, respectively. MCA and intracranial internal carotid artery (ICA) cerebral blood flow velocity (CBFV) asymmetry, together with a large ICA-to-MCA gradient, were associated with the presence of mismatch. The combined use of 2 TCD parameters (MCA CBFV asymmetry of > or = 30% and ICA-to-MCA gradient > or = 20 cm/sec) had a sensitivity of 75%, specificity of 80%, positive predictive value of 82%, and negative predictive value of 73% at detecting mismatch cases.
Diffusion-perfusion mismatch appears to be associated with interhemispheric asymmetry between MCA and ICA CBFVs, and a large CBFV gradient between the ICA and MCA on the affected side. Prospective studies are required to verify these observations and to determine whether TCD can be used to follow patients with mismatch.
Journal of Neuroimaging 01/2003; 13(1):34-42. · 1.51 Impact Factor
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Archives of Neurology 08/2002; 59(7):1074-6. · 7.58 Impact Factor
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ABSTRACT: BACKGROUND: New treatment modalities aimed to decrease both mortality and morbidity in patients with stroke are of the greatest necessity. The rationale for the use of glycerol in stroke is that brain edema is one of the most evident effects of ischemia and a common cause of death and morbidity.
REVIEW SUMMARY: In this review, we describe the basic mechanisms leading to accumulation of brain edema in stroke, followed by a discussion of the pharmacology of glycerol and its properties on brain hemodynamics and metabolism in both normal and pathologic circumstances. We also discuss all of the available trials in the English literature of glycerol for acute stroke.
CONCLUSIONS: Glycerol can be used safely to decrease the brain edema associated with ischemic stroke. However, its routine use has not been proven to significantly decrease morbidity or mortality in this setting. It is apparent that the beneficial effects of glycerol in brain ischemia cannot be explained solely on the basis of its hyperosmolar properties.
(THE NEUROLOGIST 6:338-347, 2000)
(C) 2000 Lippincott Williams & Wilkins, Inc.
The Neurologist 10/2000; 6(6). · 1.26 Impact Factor
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Headache The Journal of Head and Face Pain 42(7):695-6. · 2.52 Impact Factor
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ABSTRACT: Diagnosing TIA can be difficult, since evidence of brain ischemia is habitually lacking on CT and conventional MR imaging. It has been suggested that patients with acute brain infarction on neuroimaging should be considered stroke cases instead of TIA, regardless of duration of symptoms, implying that optimal diagnostic methods need to be utilized. We therefore postulated that perfusion-weighted MR imaging (PW imaging) would be useful in the diagnosis of TIA.
Retrospective analysis of 22 patients with reversible neurologic symptoms lasting less than 24 hours, assessed with DW and PW imaging.
MR imaging was abnormal in 15 patients (68%): 12 had abnormal DW imaging, four had both DW and PW imaging defects (all with a mismatch) and three had an isolated PW imaging abnormality. There were no differences in symptom duration, stroke etiology or cardiovascular risk factors between patients with abnormal MR imaging and those with unremarkable scan. Patients with mismatch were more likely to need conventional angiography or other cerebrovascular procedures.
The combined use of DW imaging and PW imaging provided evidence of brain ischemia in most patients with clinical diagnosis of TIA. Prospective studies using follow-up MR imaging are required to determine the outcome of affected tissue, as well as the clinical implications of DW-PW imaging abnormalities.
American Journal of Neuroradiology 25(10):1645-52. · 2.93 Impact Factor
