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Biomedical subjects

J Biller

Publications and source records attributed to J Biller.

At least 73 records · Page 4Linked to original sources
PubMed1991

Ischemic cerebrovascular complications and risk factors in idiopathic hypertrophic subaortic stenosis.

To determine the risk and time to cerebrovascular complications with idiopathic hypertrophic subaortic stenosis, we studied 119 patients (66 men and 53 women) with evidence of this disease based on strict echocardiographic criteria and followed them up for a mean +/- SEM of 6.5 +/- 0.6 years. Cerebral ischemic events occurred in 26 patients (22%), and in five patients stroke was the initial presenting event. Men had cardiac symptoms at a younger age than women, but there was no significant difference in age at the time of stroke. Cardioembolic cerebrovascular events were associated with atrial fibrillation and left atrial enlargement, whereas atheroembolic events were associated with hypertension. An increased risk of stroke was associated with female sex, mitral anulus calcification, hypertension, and atrioventricular conduction delay. Unlike most previous series, this study shows that patients with idiopathic hypertrophic subaortic stenosis may present with stroke.

Adult↗
PubMed1991

Mortality in acute cerebral infarction in young adults--a ten-year experience.

We reviewed the one-month mortality among 213 patients aged fifteen to forty-five years (mean thirty-five) with acute cerebral infarction (CI) evaluated during the period July 1, 1977, to February 1, 1988. Atherosclerotic cerebral infarction (ACI) was diagnosed in 59 (27.7%) patients, 53 (24.9%) had non-atherosclerotic vasculopathies (NAV); 46 (21.6%) had cardioembolic infarcts (CEI). Hematologically related disorders were diagnosed in 30 (14.1%) patients; the cause of CI could not be established in 25 (11.7%) patients. Fourteen patients (9 men, 5 women, mean age 34.8 years), (6.6%) died within thirty days of their CI: 7 had CEI (7/46,15.2%); 4 had ACI (4/59, 6.7%); and 3 had NAV (3/53, 5.6%). Our data suggest that young patients with acute CI have a thirty-day mortality rate lower than older patients. Deaths were most common in patients with CEI. Brain edema and herniation accounted for 6 (43%) of the deaths.

Acute Disease↗
PubMed1991

Medical management of acute cerebral ischemia in the elderly.

Stroke ranks third as a cause of death in much of the industrial world, surpassed only by heart disease and cancer. Thrombotic and embolic arterial occlusions are the leading causes of cerebral infarction. Once a major cerebral infarction has occurred, therapy is limited to the prevention of complications and rehabilitation. Identification and treatment of stroke-prone patients are now not a standard part of medical practice. However, the proper management of the patient with acute cerebral ischemic or progressing stroke is a subject of debate. Treatment of progressing or acute cerebral ischemia is aimed at prevention of infarction in areas of the brain that are still viable. A number of therapeutic strategies are currently being investigated in the management of ischemic stroke.

Acute Disease↗
PubMed1990

Cigarette smoking. A risk factor for cerebral infarction in young adults.

To assess the impact of cigarette smoking on stroke in young adults (15 to 45 years old), we compared smoking data from 181 patients with cerebral infarction with that of 307 control subjects matched for age, gender, geographic location, and hospital admission dates. While controlling for these matching variables and hypertension, an analysis based on a conditional logistic regression model indicated that a smoker was 1.6 times more likely to have a cerebral infarction than a non-smoker (95% confidence interval, 1.07 to 2.42). There was a cumulative dose effect with each additional pack-year causing a greater risk of having a cerebral infarction. In fact, after adjusting for all other risk factors, there was a significant quadratic component to the dose-response relationships, with the result that individuals with a larger number of pack-years were invariably the stroke patients. There was no significant difference in smoking status among the various subtypes of cerebral infarction (atherosclerotic, nonatherosclerotic vasculopathy, cardioembolic, hematologic related, undetermined). These data indicate that cigarette smoking is an important risk factor for cerebral infarction in young adults. Risk factor modification through cessation of smoking may reduce the risk of ischemic stroke in young adults.

Adolescent↗
PubMed1990

Circadian variation in onset of acute ischemic stroke.

A circadian pattern for the onset of myocardial and cerebral infarction has been identified. To evaluate this phenomenon further, we analyzed prospectively collected data from 151 patients with acute ischemic stroke. The number of strokes per 6-hour period were the following: midnight to 6 AM, 20 (13%); 6 AM to noon, 86 (57%); noon to 6 PM, 21 (14%); and 6 PM to midnight, 24 (16%). This pattern was not affected by previous use of aspirin. The most frequent time of onset was 6 AM to noon for all subgroups of ischemic stroke: small artery, 71%; cardioembolic, 62%; large artery atherothrombotic, 57%; large artery atheroembolic, 46%; and "other" or unknown cause, 40%. We also investigated the time between awakening and stroke onset in 145 patients and found that 24% of ischemic strokes occurred within the first hour after awakening. Our data demonstrate that an early morning peak exists for all subtypes of stroke. Our data also suggest that the most critical period is the first hour after awakening.

Acute Disease↗
PubMed1990

Cardiac evaluation of the patient with stroke.

Coronary artery disease and ischemic cerebrovascular disease are leading causes of morbidity and mortality in the United States. Coronary artery disease often coexists with asymptomatic carotid artery atherosclerosis, transient ischemic attacks, or ischemic stroke. Numerous studies have shown that mortality from all forms of ischemic cerebrovascular disease is primarily due to coronary artery disease. Thus, there is increasing interest in identifying coronary artery disease in patients with cerebrovascular disease, including those without clinical manifestations of heart disease. We review the use of current noninvasive techniques to detect coronary artery disease and present practical approaches to screen for ischemic heart disease. Current diagnostic imaging methods for potential cardioembolic sources of cerebral infarction are also discussed.

Atrial Fibrillation↗
PubMed1990

Transient monocular visual loss patterns and associated vascular abnormalities.

To determine if certain transient monocular visual loss patterns predict the associated vascular abnormalities, we prospectively evaluated 100 consecutive patients. Each patient had hematologic tests, a carotid artery study (arteriography in 74, duplex ultrasonography in the remaining 26), and an ophthalmologic examination. Patients with altitudinal or lateralized transient monocular visual loss were more likely to have carotid artery stenosis, carotid artery ulceration, cardiac sources of emboli, or visible retinal emboli than patients with other visual loss patterns. Our findings suggest that altitudinal or lateralized transient monocular visual loss is primarily caused by embolism but that other visual loss patterns are usually caused by nonembolic mechanisms.

Adult↗
PubMed1990

Retinal infarction during sleep and wakefulness.

Brain and retinal infarctions during sleep have been attributed to focal hypoperfusion caused by systemic hypotension combined with underlying arterial stenosis, rather than to embolism. Because some retinal emboli may be visualized on ophthalmoscopy, we studied 24 consecutive patients (18 men and six women) aged 26-78 (mean 58) years with recent retinal infarction and determined whether the infarction had occurred during sleep or wakefulness. All patients underwent dilated ophthalmoscopy and a carotid artery study (arteriography in 20, duplex ultrasound in the remaining four), and 12 had echocardiography. Retinal infarction occurred during sleep at an unexpectedly rate (14 of 24 observed compared with eight of 24 expected, p = 0.02). Retinal cholesterol emboli were seen in one half of the patients regardless of whether the retinal infarction had occurred during sleep or wakefulness. Carotid artery disease was found in seven of the 14 patients in whom infarction had occurred during sleep and in eight of the 10 patients in whom infarction had occurred during wakefulness (p = 0.21). Cerebrovascular occlusive disease was not found in the five patients aged less than 50 years. Our findings suggest that embolism is a common mechanism of retinal infarction during sleep or wakefulness, that in patients aged greater than 50 years extracranial carotid artery disease is a common source of retinal emboli, and that the retina may be especially susceptible to infarction during sleep.

Cerebral Infarction↗
PubMed1990

Surgical experience with cerebral amyloid angiopathy.

Cerebral amyloid angiopathy can present as lobar intracerebral hemorrhage in an elderly person, presumably due to increased fragility of the vessels affected by amyloid deposition. For this reason, patients presenting with intracerebral hemorrhage and suspected of having cerebral amyloid angiopathy have often been treated nonsurgically. Since 1983 we have evaluated 11 patients with cerebral amyloid angiopathy (nine women and two men, mean age 73 years) who have undergone either intracerebral hematoma evacuation or brain biopsy. Nine of the 11 patients presented with intracerebral hemorrhage, which was unilobar in three patients and multilobar in six and involved the parietal lobes seven times, the frontal lobes four times, the temporal lobes four times, and the occipital lobes twice. These nine patients underwent hematoma removal, with no cases of abnormal intraoperative bleeding or recurrent hemorrhage. Six patients improved neurologically, and two were unchanged after hematoma evacuation; the remaining patient had a fatal cardiopulmonary arrest during the immediate postoperative period. During follow-up in seven patients (median 11 months, range 1 week to 74 months) none experienced a recurrent intracerebral hemorrhage and four continued to improve. Two of the 11 patients had cerebral amyloid angiopathy diagnosed by brain biopsy as part of an evaluation for dementia, also without surgical complications. This series suggests that patients with cerebral amyloid angiopathy may safely undergo operative procedures, and patients presenting with intracerebral hemorrhage may show neurologic improvement following evacuation of the hematoma.

Aged↗
PubMed1990

Neurologic complications of late prosthetic valve endocarditis.

We reviewed the records of 20 patients with late prosthetic valve endocarditis who were hospitalized at the University of Iowa between 1985 and 1988. There were 14 men and six women, aged 20-80 (mean 57.9) years. The infected valves were mechanical in 11 patients (six aortic and five mitral) and bioprosthetic in the other nine. Echocardiography in 12 patients demonstrated vegetations in one. Among the 20 patients, neurologic complications occurred in eight (40%), six of whom had mechanical valves (five mitral and one aortic). Infection with Staphylococcus aureus occurred in four of the eight patients (50%) with neurologic complications. Of the eight patients with neurologic complications, ischemic stroke was diagnosed in four, transient ischemic attacks in one, and intracranial hemorrhage in three. Prothrombin times at the time of the intracranial hemorrhage were 2.2, 1.5, and 1.3 times control in these three patients. Cerebral angiography done in four of the eight patients with neurologic complications failed to show mycotic aneurysms. Nine of the 20 patients (seven men and two women, mean age 66.8 years) died less than or equal to 90 days after the diagnosis of late prosthetic valve endocarditis. Half of the eight patients with neurologic complications died (three men and one woman, mean age 62.3 years), and all three patients with intracranial hemorrhage died. Our data suggest that the neurologic complications of late prosthetic valve endocarditis are more common with mechanical valves, particularly in the mitral position, and are associated with a high mortality.

Adult↗
PubMed1990

High-dose intravenous naloxone for the treatment of acute ischemic stroke.

To evaluate the safety and possible efficacy of high-dose naloxone for the treatment of acute cerebral ischemia, 38 patients received a loading dose of 160 mg/m2 over 15 minutes followed by a 24-hour infusion at the rate of 80 mg/m2/hr. Nausea and/or vomiting were common side effects. Naloxone was discontinued in seven patients (because of hypotension in one, bradycardia and hypotension in two, myoclonus in one, focal seizures in two, and hypertension in one); all seven patients responded to treatment and no permanent sequelae to naloxone were noted. Twelve of the 38 patients showed early neurologic improvement (by completion of the naloxone loading dose). However, there was no correlation between such a loading dose response and clinical outcome at 3 months. Our experience suggests that naloxone is safe at the dose used, but data for efficacy are inconclusive.

Acute Disease↗
PubMed1990

Spontaneous improvement after acute ischemic stroke. A pilot study.

Recent clinical studies emphasize the importance of early (less than 12 hours after onset) treatment of patients with acute ischemic stroke. Therapies have been proposed as being effective because of early clinical improvement. The frequency and degree of spontaneous improvement in such patients, however, is unknown. We prospectively evaluated the course of 29 patients (19 men, 10 women) aged 33-82 years who were seen less than or equal to 12 hours after the onset of acute ischemic stroke. Seventeen patients were first evaluated less than or equal to 6 hours and the remaining patients at 6-12 hours after onset. All patients were examined using a modified National Institutes of Health Stroke Scale at baseline, 1, 2, 3, and 6 hours. No specific treatment for acute ischemic stroke was given during this time. Improvement (defined as a decrease of greater than or equal to 2 points from baseline score) was noted at 1 hour in seven patients (24%). By 6 hours 15 patients (52%) had improved, 12 (41%) were unchanged, and two (7%) were worse. Our results suggest that spontaneous, often dramatic improvement occurs in patients with acute ischemic stroke and should be taken into consideration in the design of any trial of acute treatment.

Adult↗
PubMed1990

Comparison of two-dimensional echocardiography and ultrafast cardiac computed tomography for evaluating intracardiac thrombi in cerebral ischemia.

Two-dimensional echocardiography has a high specificity for the detection of intracardiac thrombi, but technically difficult studies are often encountered. Ultrafast cardiac computed tomography may be useful in such cases. Using transthoracic two-dimensional echocardiography and ultrafast cardiac computed tomography, we studied 36 patients with cerebral ischemia; one patient had the studies performed on two occasions, making a total of 37 sets of studies. Technical difficulties occurred in 12 echocardiographic (32%) and two ultrafast cardiac computed tomographic (5%) studies. The two techniques agreed in 29 sets of studies (78%). Among the eight discrepant sets of studies, two-dimensional echocardiography was positive for a left ventricular thrombus while ultrafast cardiac computed tomography was negative in three and equivocal in one and echocardiography was equivocal while ultrafast cardiac computed tomography was negative in two and positive in one. In the latter case, a left ventricular thrombus was confirmed at autopsy. In the other discrepant set of studies echocardiography was negative while ultrafast cardiac computed tomography revealed a left atrial and appendage thrombus. Because of its ease of performance and safety, two-dimensional echocardiography is the appropriate initial screening test for left ventricular thrombus. Ultrafast cardiac computed tomography can provide additional information in patients with technically difficult or equivocal two-dimensional echocardiographic studies or patients with cardiac disorders predisposing to atrial thrombi formation.

Adult↗
PubMed1990

Large-dose infusions of heparinoid ORG 10172 in ischemic stroke.

We evaluated the safety and possible efficacy of large doses of the heparinoid ORG 10172 in 57 patients with acute or progressing ischemic stroke. Patients received a loading bolus of the drug followed by a maintenance intravenous infusion for 7 days. The plasma level of ORG 10172 was monitored by the degree of inhibition of coagulation factor Xa. In general, the drug was well tolerated and few hemorrhagic complications occurred. Two patients with large cardioembolic hemispheric strokes had intracranial hemorrhagic complications. Most patients improved during treatment. By 3 months after the stroke, 37 patients (65%) had a favorable outcome (minimal or no residual disability). This study suggests that high-dose intravenous infusions of ORG 10172 can be safely given to patients with acute ischemic stroke.

Adolescent↗
PubMed1990

Leukoencephalopathy in cerebral amyloid angiopathy: MR imaging in four cases.

We report four cases of biopsy proved cerebral amyloid angiopathy demonstrated by MR imaging. White matter signal hyperintensities on T2-weighted spin-echo pulse sequences were present in three patients. We believe the white matter lesions associated with cerebral amyloid angiopathy are not specific to this disorder but rather reflect hypoperfusion of distal white matter resulting from vascular disease.

Aged↗