ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeDuring our annual audits of carotid endarterectomy (CEA) in Toronto metropolitan hospitals, we have been aware of major changes in the practice of this operation in recent years. To evaluate the effect of changing practice on costs of carotid endarterectomy, we have therefore compared the effects of changes in length of stay, complication rates, and other variables on cost during the last 3 years for which we have complete data.MethodsWe evaluated 757 consecutive patients, of whom 600 had CEA procedures in 3 teaching hospitals, and 190 procedures in 2 community hospitals in metropolitan Toronto. We estimated costs using a specially designed computer program. Transitional System Incorporated, including surgical complications, in patients admitted between January 1994 and December 1996.ResultsThere was a significant decrease in length of stay in both groups of hospitals, mainly due to preoperative outpatient evaluation but also due to lower complication rates, which probably reflect an increase in asymptomatic surgery in both hospital groups. Costs fell from approximately $8000 per procedure to $5000 in asymptomatic patients and from approximately $10 000 to $7000 in symptomatic patients (Can $).ConclusionsMajor changes in the management of patients undergoing CEA have resulted in a significant decrease in both length of hospital stay and utilization of postoperative intensive care. At the same time, complication rates have significantly fallen, although our mortality and morbidity figures remain slightly higher than those from published multicenter trials. Future changes in surgical practice in Canada, including noninvasive carotid imaging, should produce even lower costs within the next few years. (Stroke. 1998;29:2014-2017.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeWe sought to determine the incidence of recurrent carotid stenosis in patients in the Asymptomatic Carotid Atherosclerosis Study (ACAS) who had undergone carotid endarterectomy and were prospectively followed with Doppler ultrasound for up to 5 years.Methodsor=to60%) based up angiogram-validated Doppler data, with a 90% and a 95% positive predictive value, as well as information concerning the technologists' interpretation of percent stenosis. These 3 parameters are reported for each of 3 time intervals: within 3 months of operation (residual disease), between 3 and 18 months (early restenoses), and between 18 and 60 months (late restenosis).ResultsOf the 825 patients randomized to the surgical arm of the study, 720 actually underwent carotid endarterectomy, and 645 had complete ultrasound data. The aggregate incidence of residual and recurrent carotid stenosis for all time intervals ranged from 12.7% to 20.4%, depending on the positive predic.tive value confidence level desired. Residual disease occurred in 4.1% to 6.5%; true, early restenosis was found in 7.6% to 11.4%; and late restenosis occurred in 1.9% to 4.9%. None of the traditional risk factors showed a statistically significant effect on recurrent stenosis. The use of patch angioplasty closure reduced overall risk of restenosis from 21.2% to 7.1%, from 16.7% to 4.6%, and from 27.4% to 8.2%, depending on the PPV confidence level desired (P<0.001). Of the 136 patients judged to have recurrent stenosis, only 8 (5.9%) underwent reoperation (only 1 for symptoms). There was no correlation between late stroke and recurrent stenosis.ConclusionsCarotid endarterectomy is a durable procedure with a low rate of true restenosis, particularly when patch angioplasty is used to close the arteriotomy. (Stroke. 1998;29:2018-2025.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeIt has been proved that symptomatic patients with severe carotid stenosis benefit from endarterectomy. Currently used methods for quantitation of the severity of carotid stenosis have limitations, and the impact of endarterectomy on the operated region of carotid artery remains unknown. The purpose of this study was to examine the accuracy of a 3-D ultrasound system for quantitation of stenotic lesions and to evaluate changes in regional vessel volume and cross-sectional area after carotid endarterectomy.MethodsWe studied 14 patients with both carotid angiography and 3-D ultrasound. Of 13 patients who underwent surgery, 12 were reexamined with 3-D ultrasound after surgery. The length and volume of 20 randomly selected plaques were measured from 3-D data sets. The severity of stenosis was quantified by 3-D ultrasound using both a diameter method and an area method on cross-sectional views at the most stenotic site; the results were then compared with those from carotid angiography. The segmental vessel volume and average cross-sectional area of the operated artery both before and after endarterectomy were measured from 3-D ultrasound data.ResultsGood correlation was obtained between 3-D ultrasound and carotid angiography in quantitative analysis of carotid stenosis (SEE=12.4%, r=0.76, and mean difference=7.0 +/- 12.3% with the diameter method; SEE=10.5%, r=0.82, and mean difference=1.8 +/- 10.5% with the area method by 3-D ultrasound). 3-D ultrasound had excellent reproducibility and small intraobserver and interobserver variability in plaque length and volume measurements. No significant changes in segmental vessel volume and average cross-sectional area of the operated artery were observed after surgery in patients with suture closure. However, a significant increase in segmental vessel volume was obtained in patients with polyfluorethylene patches applied to the surgical opening of the artery.Conclusions3-D ultrasound can be used for both qualitative and quantitative analysis of plaques in the carotid artery and to detect and quantify significant carotid stenosis. Its volumetric potential has important clinical implications in serial follow-up studies for observing the progression or regression of stenotic lesions and for evaluating the outcome of interventional procedures such as endarterectomy or stent placement. (Stroke. 1998;29:2026-2031.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeWe sought to assess the clinical value of regional cerebral saturation (rSo2) obtained by means of the cerebral oximeter INVOS 3100A (Somanetics) in comparison to monitoring of somatosensory evoked potentials (SEP) for the reliable detection of severe cerebral ischemia requiring shunt placement in the individual patient undergoing carotid surgery under general anesthesia.MethodsIn 317 patients undergoing reconstructive surgery on the internal carotid artery, simultaneous recordings of SEP and rSo2were obtained throughout the operation.ResultsAll 287 patients with preserved cortical SEP remained neurologically intact. Shunt placement was performed in 27 patients (9%) after flattening of cortical SEP during cross-clamping of the internal carotid artery. A stable rSo2value just before cross-clamping and the lowest value after cross-clamping were registered, and the decrease was calculated. A statistically significant (P<0.01) decrease of rSo2after cross-clamping could be found in patients without (64.9 +/- 8.3% to 60.9 +/- 9.9%) as well as in patients with consecutive loss of cortical SEP (65.8 +/- 9.1% to 56.1 +/- 13.4%). The difference of the decrease of rSo2in both groups was highly significant (6.9 +/- 9.0% versus 15.6 +/- 14.0%; P<0.001). However, substantial interindividual variability of rSo2and derived change of rSo2did not allow the definition of a threshold value indicating need of shunt placement.ConclusionsThe reliability of SEP for the detection of clamp-related hypoperfusion has been reaffirmed. As long as rSo2threshold values indicating critical cerebral ischemia are not defined, therapeutic interventions based on monitoring with the cerebral oximeter INVOS 3100A are not justified. (Stroke. 1998;29:2032-2037.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeWe correlated the mean transcranial Doppler blood flow velocity (FVm) during carotid endarterectomy with the functional collateral pathway(s) documented by angiography.MethodsThree patient groups were established: group 1 was dependent on the anterior communicating artery, group 2 on the anterior communicating artery and ipsilateral posterior communicating artery, and group 3 on the ipsilateral posterior communicating artery. Continuous middle cerebral artery FVm and electroencephalographic monitoring were performed in 45 patients during carotid endarterectomy.ResultsClamped FVm was lowest in group 3 at 17 +/- 9 cm/s versus 36 +/- 16 and 33 +/- 11 cm/s for groups 1 and 2 (P<0.01). FVm values in groups 1 and 2 were similar. There was significant cerebral arterial vasodilation in group 3 patients on the basis of a pulsatility index of 0.38 +/- 0.15. The maximum FVm after clamp release was similar among the 3 groups. Normalized blood flow velocity 1 minute before release of the clamp was increased from the minimum flow velocity after clamping only in group 1 and 2 patients.ConclusionsThe ipsilateral posterior communicating artery is a minor collateral pathway during acute carotid occlusion that contributes little to the collateral flow if there is a functional anterior communicating artery. Collateral flow through the middle cerebral artery is not recruited during occlusion in group 3 patients. The reperfusion FVm transient is independent of the primary collateral pathway. Documentation of functional collateral pathways on the basis of Doppler or angiographic examination may be advantageous in future studies since it can provide the basis for comparison among studies. (Stroke. 1998;29:2038-2042.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeGenetic polymorphism at the paraoxonase locus is associated with serum concentration and activity of paraoxonase and with increased risk for coronary heart disease. Two frequent polymorphisms present at the paraoxonase gene are the methionine (M allele) leucine (L allele) interchange at position 54 and the arginine (B allele) glutamine (A allele) interchange at position 191. This is the first study to determine the effect of these polymorphisms on carotid atherosclerosis.MethodsThe paraoxonase genotypes at positions 54 and 191 of 316 randomly selected individuals aged 44 to 75 years were determined by polymerase chain reaction-based restriction enzyme digestion. Carotid atherosclerosis was assessed by color-coded Duplex scanning and was graded on a 5-point scale ranging from 0 (normal) to 5 (complete luminal obstruction).ResultsThe LL, LM, and MM genotypes at position 54 were noted in 137 (43.4%), 132 (41.8%), and 47 (14.9%) subjects; the AA, AB, and BB genotypes at position 191 occurred in 172 (54.4%), 124 (39.2%), and 20 (6.3%) individuals. The LL genotype was significantly associated with the presence and severity of carotid disease (P=0.022), whereas the 191 polymorphism had no effect. Logistic regression analysis with age and sex forced into the model demonstrated plasma fibrinogen (odds ratio [OR], 1.005 per mg/dL), LDL cholesterol (OR, 1.01 per mg/dL), cardiac disease (OR, 1.75), and the paraoxonase LL genotype to be significant predictors of carotid atherosclerosis. The ORs for the associations with age and sex were 1.09 (P=0.0003) and 1.66 (P=0.052) per year.ConclusionsThese data suggest that the paraoxonase LL genotype may represent a genetic risk factor for carotid atherosclerosis. (Stroke. 1998;29:2043-2048.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposePhysiologically, it appears plausible for physical activity to decrease stroke risk; however, epidemiological studies have produced mixed findings. Furthermore, few studies have examined specific kinds and intensities of activities. The purpose of this study was to examine the association between physical activity, including its various components (walking, climbing stairs, participation in sports and receational activities), and stroke risk.MethodsThis was a prospective cohort study of 11 130 Harvard University alumni (mean age, 58 years) without cardiovascular disease and cancer at baseline. Men reported their walking, stair climbing, and participation in sports or recreation on baseline questionnaires in 1977. Stroke occurrence was assessed with another questionnaire in 1988. Death certificates were obtained for decedents through 1990 to determine strokes not previously reported (total strokes=378). We used Cox proportional hazards regression to estimate the relative risks and 95% CIs for stroke occurrence associated with physical activity.Resultsor=to4.5 METs, or multiples of resting metabolic rate) each showed U-shaped relations to stroke risk, with the risk being significantly lower at the nadir of the curve. Light intensity activities (<4.5 METs), however, were unrelated to stroke risk.ConclusionsPhysical activity is associated with decreased stroke risk in men. A decreased risk was observed at energy expenditures of 1000 to 1999 kcal/wk, with further risk decrement seen at 2000 to 2999 kcal/wk but not beyond. Confirmation of the U-shaped relation observed in these data requires similar observations in other populations. (Stroke. 1998;29:2049-2054.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeMany stroke survivors have minimal to moderate neurological deficits but are physically deconditioned and have a high prevalence of cardiovascular problems; all of these are potentially modifiable with exercise. The purposes of this randomized, controlled pilot study were (1) to develop a home-based balance, strength, and endurance program; (2) to evaluate the ability to recruit and retain stroke subjects; and (3) to assess the effects of the interventions used.MethodsTwenty minimally and moderately impaired stroke patients who had completed inpatient rehabilitation and who were 30 to 90 days after stroke onset were randomized to a control group or to an experimental group that received a therapist-supervised, 8-week, 3-times-per-week, home-based exercise program. The control group received usual care as prescribed by the patients' physicians. Baseline and postintervention assessments included the Fugl-Meyer Motor Assessment, the Barthel Index of Activities of Daily Living (ADL), the Lawton Scale of Instrumental ADL, and the Medical Outcomes Study-36 Health Status Measurement. Functional assessments of balance and gait included a 10-m walk, 6-Minute Walk, and the Berg Balance Scale. Upper extremity function was evaluated by the Jebsen Test of Hand Function.ResultsOf 22 patients who met study criteria, 20 completed the study and 2 refused to participate. The experimental group tended to improve more than the control group in motor function (Fugl-Meyer Upper Extremity: mean change in score, 8.4 versus 2.2; Fugl-Meyer Lower Extremity: 4.7 versus -0.9; gait velocity: median change, 0.25 versus .09 m/s; 6-Minute Walk: 195 versus 114 ft; Berg Balance Score: 7.8 versus 5; and Medical Outcomes Study-36 Health Status Measurement of Physical Function: 15.5 versus 9). There were no trends in differences in change scores by the Jebsen Test of Hand Function, Barthel Index, and Lawton Instrumental ADL Scale.ConclusionsThis study demonstrated that a randomized, controlled clinical trial of a poststroke exercise program is feasible. Measures of neurological impairments and lower extremity function showed the most benefit. Effects of the intervention on upper extremity dexterity and functional health status were equivocal. The lasting effects of the intervention were not assessed. (Stroke. 1998;29:2055-2060.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Background and PurposeSouth Carolina and the southeastern United States have maintained the highest stroke mortality in the country. The Anderson and Pee Dee Stroke Study is an assessment of cerebrovascular disease incidence in 2 geographically defined communities in the stroke belt.MethodsStrokes were identified in the Anderson and Pee Dee areas of South Carolina. All hospitalized and out-of-hospital deaths occurring during 1990 among the residents of these 2 areas were included. Strokes were classified by an independent panel of neurologists using a standard protocol that included specific criteria for stroke and subtypes.ResultsThe overall age-adjusted stroke incidence rates (per 100 000 population) were significantly higher in the Pee Dee population (293.1) compared with Anderson (211.2). The geographic differences were more dramatic in the younger age groups of 35 to 64 years. Likewise, incidence rates for blacks were nearly twice the rates for whites. The rates in the Pee Dee were higher than the rates from other studies in the United States and other parts of the world. Although the stroke subtypes did not vary between the 2 regions, race-sex differences were identified.ConclusionsHigh stroke incidence and disease rates persist for all 4 race-sex groups in the Southeast and reflect similar risks as mortality rates. However, geographic variability in stroke rates suggests that the pattern of disease in the region is not so much a "belt" of increased stroke in contiguous areas but rather more a "necklace" of different levels of risk. These results should be useful in the identification of factors associated with this geographic enigma. (Stroke. 1998;29:2061-2068.)

ISSN:0039-2499    

出版商:OVID    

年代:1998

数据来源: OVID