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D Lefkowitz

Publications and source records attributed to D Lefkowitz.

At least 19 recordsLinked to original sources
PubMed2002

Development of a method for extraction of methyl tert-butyl (MTBE) from soil samples.

Methyl tert-Butyl Ether (MTBE) is ubiquitous in both ground and surface waters in the United States, and it can also be found in many unsaturated soil systems. Until recently, MTBE was not thought to adsorb appreciably to soil solids. MTBE, however, will adsorb to some soil types, and additionally, can be found in both soil water and soil gas. Since sorbed MTBE can serve as a long term, low level, source to water systems, a practical method for quantifying soil concentrations is needed to fully understand the environmental impact of MTBE. In this paper, we examine the analytical parameters critical to MTBE extraction methods, including extraction solvent and gas chromatograph characteristics. As the result, we have discovered toluene to be an effective solvent (exhibiting adequate recovery and excellent separation from MTBE) using a GC/FID with Suppelcowax column.

Adsorption↗
PubMed2001

Cluster analysis and patterns of findings on cranial magnetic resonance imaging of the elderly: the Cardiovascular Health Study.

OBJECTIVE: To characterize patterns of findings on cranial magnetic resonance imaging (MRI) of the elderly using a statistical technique called cluster analysis. SUBJECTS AND METHODS: The Cardiovascular Health Study is a population-based, longitudinal study of 5888 people 65 years and older. Of these, 3230 underwent cranial MRI scans, which were coded for presence of infarcts and grades for white matter, ventricles, and sulci. Cluster analysis separated participants into 5 clusters based solely on patterns of MRI findings. Participants comprising each cluster were contrasted with respect to cardiovascular risk factors and clinical manifestations. RESULTS: One cluster was low on all the MRI findings (normal) and another was high on all of them (complex infarcts). Another cluster had evidence for infarcts alone (simple infarcts), whereas the last 2 clusters lacked infarcts, one having enlarged ventricles and sulci (atrophy) and the other having prominent white matter changes and enlarged ventricles (leukoaraiosis). Factors that distinguished these clusters in a discriminant analysis were age, sex, several measures of hypertension, internal carotid artery wall thickness, smoking, and prevalent claudication before the MRI. The atrophy group had the highest percentage of men and the normal group had the lowest. Cognitive and motor performance also differed across clusters, with the atrophy cluster performing better than may have been expected. CONCLUSIONS: These MRI patterns identified participants with different vascular disease risk factors and clinical manifestations. Results of these exploratory analyses warrant consideration in other populations of elderly people. Such patterns may provide clues about the pathophysiology of structural brain changes in the elderly.

Aged↗
PubMed2000

Daytime sleepiness predicts mortality and cardiovascular disease in older adults. The Cardiovascular Health Study Research Group.

INTRODUCTION: As part of the baseline examination in the Cardiovascular Health Study, sleep disturbance symptoms including snoring and daytime sleepiness, were assessed as potential risk factors or precipitants of cardiovascular disease (CVD). Because of the association of sleep disturbance with poorer health and the possible associations of sleep apnea with CVD, we hypothesized that those with poorer sleep or daytime sleepiness may be at increased risk of mortality or incident CVD. SETTING: Participants (n = 5888) were recruited in 1989, with an additional minority cohort recruited in 1993, in four US communities for a cohort study designed to evaluate risk factors for cardiovascular disease. METHODS: An interview-administered questionnaire regarding health and sleep habits with ongoing ascertainment of total mortality and cardiovascular disease morbidity and mortality, including total CVD morbidity and mortality, incident myocardial infarction, and congestive heart failure. RESULTS: Daytime sleepiness was the only sleep symptom that was significantly associated with mortality in both men and women. The unadjusted hazard ratio was 2.12 (1.66, 2.72) in women and 1.40 (1.12, 1.73) in men. Men who reported difficulty falling asleep also had an increased mortality rate (HR = 1.43 (1.14, 1.80)) which was not seen in women. The risks were attenuated with adjustment for age but remained significant for daytime sleepiness in women (HR = 1.82 (1.42, 2.34)) and for difficulty falling asleep in men. (HR = 1.29 (1.03, 1.63)). Frequent awakenings, early morning awakening, and snoring were not associated with a significantly increased risk of mortality in these older men and women. Crude event rates were evaluated for total incident cardiovascular morbidity and mortality, incident myocardial infarction, and incident congestive heart failure (CHF). Incident CVD rates were higher in both men and women with daytime sleepiness. The aged adjusted HR was 1.35 (95% CI = 1.03, 1.76) in men and was 1.66 (95% CI = 1.28, 2.16) in women. Incident CVD was not higher in those with any other sleep disturbance including snoring. The risk of CVD events associated with daytime sleepiness was attenuated but remained significant in women after adjustment for age. Incident myocardial infarction (MI) rates were also higher in women with daytime sleepiness but were not significantly higher in men. Incident CHF rates were increased in both men and women with daytime sleepiness. In men, the age adjusted HR was 1.49 (95% CI, 1.12- 1.98) and in women, was 2.21 (95% CI, 1.64-2.98). Women reporting both daytime sleepiness and frequent awakening had a hazard ratio of 2.34 (95% CI, 1.66-3.29) for incident CHF compared with those with daytime sleepiness but without frequent awakening. This interaction was not found in men. CONCLUSIONS: In this study, daytime sleepiness was the only sleep disturbance symptom that was associated with mortality, incident CVD morbidity and mortality, MI, and CHF. These findings were stronger in women than men, i.e., the associations persisted for mortality, CVD, and CHF in women after adjustment for age and other factors. Thus, a report of daytime sleepiness identifies older adults at increased risk for total and cardiovascular mortality, and is an independent risk factor in women.

Age Factors↗
PubMed2000

Echocardiographic validation of gated SPECT ventricular function measurements.

UNLABELLED: Left ventricular (LV) volumes are valuable prognostic indicators in the management of coronary artery disease and traditionally have been obtained by x-ray contrast angiography or echocardiography. There now are several scintigraphic methods to compute volumes that are based on different LV modeling assumptions. Both the reasons that calculations from different nuclear techniques can disagree with one another and the relationship of these values to the more conventional echocardiographic measurements must be investigated thoroughly for calculations to be interpretable for individual patients. METHODS: Echocardiographic volumes were determined in 33 retrospective subjects with coronary artery disease (mean age, 61 +/- 12 y; 42% men; 70% with abnormal perfusion and 58% with abnormal segmental wall motion) using the modified Simpson's rule technique applied to digitized apical 4-chamber and apical 2-chamber views of 4 averaged heartbeats. These volumes were compared with those from 3 gated SPECT methods based on Simpson's rule LV modeling similar to standard echocardiographic algorithms (SPECT EF from St. Luke's-Roosevelt Hospital) (method 1), Gaussian myocardial count profile curve fitting (QGS from Cedars-Sinai Medical Center) (method 2), and an endocardial model based on perfusion sampling and count-based thickening (Cardiac Toolbox from Emory University) (method 3). RESULTS: By ANOVA, there were no significant differences among ejection fractions (EFs), but there were for volumes. Paired t test analysis showed volumes from methods 2 and 3 to be significantly larger than echocardiographic volumes and larger than those of method 1. Linear regression analysis comparing gated SPECT and echocardiographic volumes showed a nearly identical strong correlation (r = 0.92; P < 0.000001) for all 3 methods. Excellent correlation also was found among gated SPECT volumes from the 3 methods (r = 0.94). Bland-Altman analysis and t tests showed that method 1 volumes (70 +/- 61 mL) were the same as for echocardiography (77 +/- 55 mL), but volumes were overestimated by method 2 (105 +/- 74 mL) and method 3 (127 +/- 92 mL), particularly for larger volumes. Pearson coefficients for EFs compared with echocardiography were r = 0.82, 0.75, and 0.72 for methods 1-3, respectively. EFs correlated strongly among the 3 gated SPECT methods (r = 0.86-0.92). The Fisher z test showed no differences among these methods for any of the volume or EF linear correlation analyses. CONCLUSION: All gated SPECT parameters correlated well with echocardiographic values. However, the gated SPECT method for which underlying assumptions most closely resembled those commonly used in echocardiography produced mean volume values closest in agreement with echocardiographic measurements.

Analysis of Variance↗
PubMed1998

The care of HIV-infected adults in the United States. HIV Cost and Services Utilization Study Consortium.

BACKGROUND AND METHODS: In order to elucidate the medical care of patients with human immunodeficiency virus (HIV) infection in the United States, we randomly sampled HIV-infected adults receiving medical care in the contiguous United States at a facility other than military, prison, or emergency department facility during the first two months of 1996. We interviewed 76 percent of 4042 patients selected from among the patients receiving care from 145 providers in 28 metropolitan areas and 51 providers in 25 rural areas. RESULTS: During the first two months of 1996, an estimated 231,400 HIV-infected adults (95 percent confidence interval, 162,800 to 300,000) received care. Fifty-nine percent had the acquired immunodeficiency syndrome according to the case definition of the Centers for Disease Control and Prevention, and 91 percent had CD4+ cell counts of less than 500 per cubic millimeter. Eleven percent were 50 years of age or older, 23 percent were women, 33 percent were black, and 49 percent were men who had had sex with men. Forty-six percent had incomes of less than $10,000 per year, 68 percent had public health insurance or no insurance, and 30 percent received care at teaching institutions. The estimated annual direct expenditures for the care of the patients seen during the first two months of 1996 were $5.1 billion; the expenditures for the estimated 335,000 HIV-infected adults seen at least as often as every six months were $6.7 billion, which is about $20,000 per patient per year. CONCLUSIONS: In this national survey we found that most HIV-infected adults who were receiving medical care had advanced disease. The patient population was disproportionately male, black, and poor. Many Americans with diagnosed or undiagnosed HIV infection are not receiving medical care at least as often as every six months. The total cost of medical care for HIV-infected Americans accounts for less than 1 percent of all direct personal health expenditures in the United States.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Hypoechoic plaque at US of the carotid artery: an independent risk factor for incident stroke in adults aged 65 years or older. Cardiovascular Health Study.

PURPOSE: To investigate the association between incident (first) stroke and the echogenicity of internal carotid arterial plaque at ultrasonography (US). MATERIALS AND METHODS: A cohort of 4, 886 individuals who, at baseline, were 65 years of age or older and without symptoms of cerebrovascular disease was followed up for an average of 3.3 years. Baseline clinical findings were from color Doppler and duplex US studies of the carotid arteries and a record of traditional risk factors: age, sex, presence of diabetes mellitus, pack-years of cigarette smoking, presence of hypertension, elevated systolic and diastolic blood pressure, elevated low-density lipoprotein cholesterol level. RESULTS: Incident strokes, excluding hemorrhagic strokes and strokes of cardiac origin, were seen in 104 individuals (2.1%) at risk. Age- and sex-adjusted odds ratios for incident stroke were significant for hypoechoic plaque (odds ratio, 2.53; 95% CI, 1,42,4.53). After controlling for risk factors in a Cox proportional hazards model, the relative risk (RR) of incident stroke was 1.72 (p = .015) for hypoechoic plaque and 2.32 (P = .004) for internal carotid arterial narrowing of at least 50%. In addition, hypoechoic plaque (RR, 2.78; CI, 1.36,5.69) and 50%-100% stenosis (RR, 3.08; CI, 1.28, 7.41) were associated with ipsilateral, nonfatal stroke. CONCLUSION: In asymptomatic adults aged 65 years or older, that risk of incident stroke was associated with two US features: hypoechoic internal carotid arterial plaque and an estimated internal carotid arterial stenosis of 50%-100%.

Aged↗
PubMed1998

Asymptomatic internal carotid artery stenosis defined by ultrasound and the risk of subsequent stroke in the elderly. The Cardiovascular Health Study.

BACKGROUND AND PURPOSE: We sought in this study to relate carotid ultrasound findings in asymptomatic older adults to the 5-year risk of various cerebrovascular outcomes used in the Asymptomatic Carotid Atherosclerosis Study (ACAS). METHODS: The Cardiovascular Health Study (CHS) is a longitudinal study of people 65 years and older. Analyses of internal carotid artery stenosis defined by multiple different cutoffs of peak systolic velocity, rather than one particular cutoff, were performed in the 5441 participants who underwent carotid ultrasound and lacked a history of transient ischemic attack or stroke. The 5-year risks of 7 cerebrovascular disease outcomes used in ACAS were estimated for each cutoff. RESULTS: Associations with the 5-year risk of outcomes were substantially elevated only at cutoffs with high peak systolic velocities. In this population, the number of people with such high velocities was small. For example, with a cutoff of approximately 2.5 m/s, suggesting a stenosis of >70%, the 5-year risk of an ipsilateral fatal or nonfatal stroke was 5%, and only 0.5% of the group had velocities at least this high. CONCLUSIONS: In a group of older adults likely to participate in a screening program, as evidenced by willingness to participate in CHS, high peak systolic velocities consistent with high-grade carotid stenosis were uncommon and risk of subsequent cerebrovascular disease outcomes was relatively low. These findings do not suggest that similar populations of older adults would benefit from a program using ultrasound to screen for asymptomatic carotid stenosis.

Aged↗
PubMed1995

Estrogen replacement therapy and progression of intimal-medial thickness in the carotid arteries of postmenopausal women. ACAPS Investigators. Asymptomatic Carotid Atherosclerosis Progression Study.

The effect of estrogen replacement therapy (ERT) on 3-year changes in carotid intimal-medial thickness (IMT) was explored using serial B-mode ultrasound measurements collected during 1989-1993 as part of the Asymptomatic Carotid Atherosclerotic Progression Study (ACAPS). Eligibility included increased IMT and elevated low density lipoprotein cholesterol. Of the 186 postmenopausal ACAPS women randomly assigned to receive either placebo or lovastatin, 34% reported use of ERT. Users tended to be younger than nonusers by an average of 3 years, to have more favorable high and low density lipoprotein cholesterol levels, and to be more likely to have had hysterectomies. Baseline blood pressure, body mass index, and cross-sectional IMT were similar among ERT users and nonusers. In the placebo group, IMT tended to progress among ERT nonusers but to regress among ERT users: Mean covariate-adjusted progression rates were 0.015 +/- 0.007 mm/year versus -0.012 +/- 0.012 mm/year, respectively (p = 0.05). This difference appeared to be independent of lipoprotein concentrations. Lovastatin was associated with an approximately 25% lowering of low density lipoprotein cholesterol among both ERT users and nonusers and had a marked impact on IMT progression (p = 0.004) in these women. ERT appeared to have little additional effect on IMT in women assigned to lovastatin. ERT may reduce or halt the progression of early atherosclerosis in women not receiving active lipid-lowering medication.

Adult↗
PubMed1995

Decision logic for retreatment of asymptomatic lung cancer recurrence based on positron emission tomography findings.

PURPOSE: The purpose of the study was to determine if Positron emission tomography (PET) 2-[F-18] fluoro-2-deoxy-D-glucose (FDG) imaging could detect subclinical local lung cancer recurrence and whether retreatment of such recurrence was feasible and beneficial. METHODS AND MATERIALS: Twenty patients with biopsy proven lung cancer were studied with Positron emission tomography for the purpose of detecting subclinical lung cancer recurrence over a period of 4.25 years. All patients were treated with external radiation as part or all of their therapy. Twenty patients had baseline PET and computed tomography (CT) studies for comparison with later studies. Surviving patients had a total of 40 sequential PET scans and 35 CT scans. The follow-up interval ranged from 5 to 40 months posttreatment. The differential uptake ratio (DUR) was determined for regions of interest of increased FDG uptake. RESULTS: The median DUR value of the 20 baseline PET studies was 5.59. The DUR value of greater than 3 was empirically selected as being positive for tumor detection. On baseline studies, PET had a 100% correlation with the CT findings in regard to detection of the site of primary tumor involvement. Four of 20 patients showed areas of discordance in the mediastinal and hilar areas on initial PET and CT studies. Seven of 17 patients showed discordant posttreatment PET-CT findings. Two false positive PET studies were due to radiation pneumonitis and one to macrophage glycolysis in tumor necrosis. For detection of asymptomatic tumor recurrence, analysis of sequential PET and CT studies, biopsy results, and the patient's clinical course suggested that PET had a sensitivity of 100%, specificity of 89.3%, and accuracy of 92.5%. Computerized Tomography was found to have a sensitivity of 67%, specificity of 85%, and accuracy of 82% for detection of such early-stage recurrence. Five patients went on to have retreatment with external irradiation based upon the PET evidence. Four retreated patients had biopsies that corroborated the positive PET findings, and one patient was retreated on the basis of the qualitative appearance of the posttreatment PET study. Two of the five retreated patients remain alive without evidence of tumor to 34 months following initial therapy. CONCLUSION: Positron emission tomography scanning appears to be effective in detecting and following the progression of recurrent lung cancer. Retreatment of patients with asymptomatic recurrent tumor has resulted in absent or decreased FDG activity. Monitoring of patients with PET may provide prolonged survival in patients who otherwise would fail treatment because of local tumor recurrence.

Adenocarcinoma↗
PubMed1995

Pilot study of intravenous magnesium sulfate in refractory cardiac arrest: safety data and recommendations for future studies.

UNLABELLED: Recent case reports have evidenced a temporal association between administration of i.v. magnesium sulfate (M) and resuscitation from prolonged cardiac arrest refractory to standard (S) ACLS attempts. However, speculation has arisen that M as a vasodilator, may decrease aortic diastolic and coronary perfusion pressure (CPP), aortic systolic and cerebral perfusion pressures (CePP), which may decrease resuscitation rates and neurologic recovery, as compared to standard ACLS alone (SA). OBJECTIVE: To resolve positive beginning evidence vs. negative theory, we conducted a pilot study of M+S vs. SA in refractory cardiac arrest on resuscitation rates (% R, return of stable pulses > 30 min without CPR, first in-hospital cardiac arrest > 5-min duration) and neurologic recovery/survival to hospital discharge (SHD). METHODS: All patients from 1 January 1990-31 December 1991 at Rose Hospital, in cardiac arrest refractory to S through the first epinephrine dose (including 3 defibrillation attempts with pulseless VT/VF) were included in the data analysis, except: (1) patients with trauma, known poisoning, < 18 years, pregnancy excluded; (2) Standard ACLS alone patients with cardiac arrest < 5-min duration were not included in the SA comparison group, because the shortest cardiac arrest time before i.v. MgSO4 administration in the M+S group was 5 min. M+S (N = 29) and SA (N = 33) groups were also comparable on mean age (72-73 years) in this open-label prospective case-matched control group study. RESULTS: SHD rates were nearly equivalent between M+S (5.2%) and SA (4.5%). Complete or partial neurologic recovery, as best neurologic status post-R, occurred in 21% (6/29) M+S patients vs. 9% (3/33) SA (P = 0.17), even though cardiac arrest time on the study code call for resuscitated patients averaged shorter with SA (14.2 min) than M+S (19.8 min). M was frequently administered late in the resuscitation attempt--code call to M administration averaged 16.5 min (< 10 min in only 4/28 patients). A trend toward increased % R with M was evidenced: 21% (7/33) SA vs. 35% (10/29) M+S (P = 0.21). A temporal association between M administration and first return of spontaneous circulation (ROSC) was also documented in 4 of 10 M+S patients (pulseless electrical activity (3)/pulseless VT (1)), who had first ROSC/R occur within 0.5-2.25 min following first i.v. M bolus delivery, after 11-30 min (mean = 20 min) of continuous pulseless rhythm refractory to standard ACLS. All M+S resuscitations occurred within the dose range 2.5-5 g (i.v. push): 3/6 (50%) and 7/13 (54%) R occurred with 1-3 g and 4-5 g MgSO4, respectively (at least 11/13 patients had peripheral i.v. delivery with 4-5 g M). Analyzing post-ROSC hypotension proved important, as 50% of pts with first recorded systolic BP post-ROSC < 90 mmHg were resuscitated vs. 83% with > 90 mmHg (P = 0.10). A trend toward increased post-ROSC hypotension was evidenced with i.v. MgSO4: Recorded first or second systolic BP < 90 mmHg post-ROSC occurred in 66% of M+S vs. 42% of SA patients. All 3 M+S patients having a wide open i.v. levophed infusion as vasopressor support, started immediately post-ROSC/i.v. MgSO4 with systolic BP < 90 mmHg and continued at least 15 min (titrating to a systolic BP approximately 110 mmHg), had a temporal association between M delivery and R after 14-30 min of continuous pulselessness refractory to S. CONCLUSION: Human research determining whether i.v. MgSO4 increases long-term survival from refractory cardiac arrest should be vigorously pursued, as it is safe to proceed given the above described considerations.

Aged↗
PubMed1991

Application of positron emission tomography to neurological oncology.

PET has a promising role in neuroradiology for accurate diagnosis and prognostication of malignant tumors as well as differential diagnosis of radiation necrosis and recurrent tumors. Particularly, PET has proven its ability to accurately differentiate radiation necrosis from recurrent brain tumor. Active tumors have accelerated glycolysis, and a remarkable accumulation of FDG radiotracer in high grade brain tumors is evident on PET images. Tumor metabolism also proportionally increases with increasing pathologic grades of brain tumor, and accelerated tumor metabolism indicates a poor prognosis for the tumor.

Adult↗
PubMed1991

Asymptomatic carotid artery disease in the elderly. Diagnosis and management strategies.

Carotid atherosclerosis is commonly detected in the asymptomatic elderly and in patients with known vascular disease in other distributions. Although there has been considerable interest in carotid bruits, they are not a reliable indicator of asymptomatic stenosis. In patients with asymptomatic stenosis detected by carotid ultrasound or angiography, the annual risk of ipsilateral infarction is approximately 1% to 2%. If ischemic events occur, they are usually transient ischemic attacks. Stroke risk is higher when there is progressive stenosis, stenosis exceeding 75% to 80%, and, possibly, complicated plaque-morphologic characteristics. The treatment of asymptomatic carotid stenosis remains controversial. Antiplatelet agents are of unproven value in asymptomatic patients. The role of surgical management is disputed because of uncertainties regarding the natural history of asymptomatic stenosis and the efficacy and complication rates of endarterectomy. Pending results of several ongoing randomized clinical trials, it may be advisable to withhold endarterectomy from those asymptomatic patients with stenosis of less than 75% to 80%. Prophylactic carotid endarterectomy is not necessary in the patient with asymptomatic stenosis who will undergo another operative procedure such as coronary artery bypass.

Aged↗
PubMed1989

Cause specific mortality following cerebral infarction.

Mortality from four causes (index stroke, subsequent stroke, cardiac disease and non-cardiovascular causes) was examined during a 5 year follow-up of 1694 cerebral infarction patients admitted to 25 community hospitals between 1969 and 1973. The hazard for mortality from the index stroke was high initially, but declined to a negligible level by 6 months post-stroke. In contrast, hazards for mortality from subsequent strokes, cardiac diseases and non-cardiovascular causes each peaked midway through the first year, declined during the remainder of that year, and then increased in the latter part of the follow-up. Proportional hazards analysis indicated that advanced age and increased stroke severity were the only factors significantly related to increased risk from each of the four causes of death. Other risk factors were significant only for one or two select causes of death. White patients were less likely to die from subsequent strokes, but more likely to die from cardiac diseases, than were non-white patients (primarily blacks). Males were more likely to die from both the index stroke and non-cardiovascular causes than females. A history of cardiac disease increased the risk of death from both the index stroke and from future cardiac events, while a history of hypertension or diabetes increased the risk of death from non-cardiovascular causes, and a history of previous stroke increased the risk of death from subsequent stroke.

Age Factors↗
PubMed1988

Enhancement of macrophage spreading and phagocytosis by peroxidative enzymes.

Macrophages stimulated by various substances exhibit altered morphology, metabolism, and enhanced phagocytosis. The present studies were done to show if peroxidative enzymes would affect macrophage spreading and phagocytosis. Resident peritoneal macrophages, collected from C57BI mice were exposed to various concentrations of peroxidases and compared with appropriate controls. Results indicated that 0.01 microM myeloperoxidase (MyPO), 0.09 microM horseradish peroxidase (HRP), 0.16 microM lactoperoxidase (LPO) and 70 microM microperoxidase (MPO) significantly enhanced macrophage spreading. It was also noted that peroxidases were able to stimulate phagocytosis by increasing the number of cells with internalized zymosan at least twofold. Stimulation of these functions suggests a possible role of endogenous peroxidases as natural cell activators.

Animals↗
PubMed1986

Asymptomatic carotid bruit and stenosis. A prospective follow-up study.

We observed 70 patients with asymptomatic carotid bruits with and without stenoses for cerebral and myocardial ischemic events. Four patients developed transient ischemic attacks (TIAs) without subsequent cerebral infarctions; all of the TIAs occurred distal to vessels with greater than or equal to 50% stenoses. Three cerebral infarctions occurred, but only one was distal to a vessel with stenosis greater than or equal to 50%. Six myocardial infarctions occurred, predominantly in patients with previous myocardial infarctions, congestive heart failure, and left ventricular hypertrophy. Our results confirm previous reports that an asymptomatic carotid stenosis is more often complicated by a TIA than an unheralded cerebral infarction. Cerebral infarctions that do occur are often only marginally related to the carotid bifurcation lesion. In patients with asymptomatic carotid bruit and stenosis, myocardial infarctions occur more frequently and are more commonly the cause of death than cerebral infarctions.

Aged↗