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1.
Replacement of the ascending aorta. Early and late results   总被引:1,自引:0,他引:1  
From 1978 through 1987, 225 patients underwent operations that included replacement of the ascending aorta. One hundred twenty-three patients underwent composite aortic valve and ascending aortic replacement, 30 had aortic valve replacement with separate graft replacement of the ascending aorta, and 72 underwent replacement of the ascending aorta without aortic valve replacement. Thirty-one (13.8%) in-hospital deaths occurred. Univariate testing of preoperative and operative variables followed by logistic regression analyses identified miscellaneous aortic disease, coronary artery bypass grafting, aortic arch replacement, emergency operation, surgical date (1978 to 1983), and age (all p less than 0.05) as factors having independent association with in-hospital mortality. Follow-up of in-hospital survivors (mean interval 46 months, range 8 to 123 months) documented an overall 5-year survival rate of 76%, 83% after primary operation and 37% after reoperation. Univariate analyses followed by multivariate testing indicated that previous operation (p less than 0.0001) and a history of preoperative neurologic symptoms (p = 0.021) were associated with decreased late survival. At follow-up 88% of late survivors were free of symptoms. Seven patients have undergone reoperation 1 day to 69 months postoperatively. Although the in-hospital mortality for operations that include ascending aortic replacement exceeds that for isolated aortic valve replacement, the late death rate and rate of reoperation are low.  相似文献   
2.
Is There an Advantage to Repairing Infected Mitral Valves?   总被引:5,自引:0,他引:5  
Background. The therapy for native mitral valve endocarditis is in evolution. Antibiotics have significantly improved survival rates, but patients with complications of endocarditis may require surgical treatment.

Methods. Between January 1985 and December 1995, 146 patients underwent surgical therapy (repair or replacement) for native mitral valve endocarditis. All patients had documented bacterial endocarditis. Univariate and multivariate analyses were performed to determine predictors of hospital death, long-term event-free survival, and probability of repair. Patients were evaluated in three groups: all patients, patients with acute endocarditis, and patients with chronic endocarditis.

Results. There were ten hospital deaths (6.8%). Patients undergoing repair had a lower hospital mortality rate (p = 0.008) then those having replacement. Event-free survival was improved after mitral valve repair in the overall group (p = 0.02) and in the group with healed (chronic) endocarditis (p = 0.05). Although the acute endocarditis group demonstrated an improved event-free survival rate after mitral valve repair versus replacement (74% versus 20% at 6 years), this did not reach statistical significance.

Conclusions. We conclude that mitral valve repair is preferable to mitral valve replacement when possible, in patients with complications of endocarditis, as repair results in a lower hospital mortality and an improved long-term survival.  相似文献   

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The Class of 1989 was part of the Minnesota Heart Health Program, a research and demonstration project designed to reduce cardiovascular disease in three intervention communities. This paper describes the long-term outcomes of a school- and community-based intervention on healthy eating behaviors in one intervention and matched reference community. Beginning in the sixth grade (1983), seven annual waves of behavioral measurements were taken from both communities (baseline N = 2376). Self-reported data were collected at each time period including measures of knowledge and preferences for certain foods, and food salting behavior. Data were analyzed using an ANCOVA model adjusting for baseline dependent variable differences, with the school as the unit of analysis. Knowledge, healthy food choices and restraint in food salting behavior variables were significantly higher throughout most of the follow-up period in the intervention community for females. Males also indicated greater knowledge of healthier choices in the intervention community and greater restraint in salting behavior but results are less conclusive for healthy food choices. These results suggest that multiple intervention components such as behavioral education in schools coupled with community-wide health promotion strategies can produce modest but lasting improvement in adolescent knowledge and choices of heart healthy foods and less frequent food salting practices, and that this improvement is most notable among females.  相似文献   
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BACKGROUND: The purpose of this study was to determine the prevalence, outcome, and operative strategies for patients having injury to a patent left internal thoracic artery (LITA) graft to the left anterior descending coronary artery (LAD) at coronary reoperation. METHODS: Of 655 patients with a patent LITA graft to the LAD undergoing coronary reoperation from 1986 to 1997, 35 (5.3%) sustained intraoperative injury to the LITA graft. RESULTS: Strategies to restore flow to the LAD included new saphenous vein graft to the LAD in 15 patients, saphenous vein graft to the LITA stump in 7, saphenous vein graft to the LAD and repair of the LITA graft in 6, and other strategies in 7. All or part of the LITA graft to the LAD was salvaged in 20 patients (57%). Fourteen patients (40%) sustained perioperative myocardial infarction, and 3 patients died (8.6%). The 3 patients who died all had stenosis or thrombosis of the graft to the LAD documented at autopsy. CONCLUSIONS: We conclude that (1) the prevalence of injury to a patent LITA graft is 5.3%; (2) a variety of techniques can be used to restore blood flow to the LAD; and (3) ineffective revascularization of the LAD in this situation is associated with operative mortality. At primary coronary artery bypass grafting, the LITA pedicle should be positioned in the left chest away from the posterior sternal table; this strategy may minimize the risk of LITA graft injury at coronary reoperation.  相似文献   
8.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age.  相似文献   
9.
The research community has criticized Drug Abuse Resistance Education (D.A.R.E.) because the extant literature indicates a lack of evidence that the elementary school program prevents drug use. Yet D.A.R.E. continues to be the most widely implemented drug use prevention program in the United States and has considerable community support. To date, the junior high D.A.R.E. program has not been evaluated. The Minnesota DARE PLUS Project is a randomized trial of 24 schools and communities. During 1999-2001, students in eight schools will receive the junior high D.A.R.E. curriculum in 7th grade; eight schools also will receive the curriculum as well as additional parent involvement, peer leadership, and community components in the 7th and 8th grades; and eight schools will serve as controls. This article describes the background and conceptualization, the curriculum and additional intervention components, and the evaluation methods of the DARE PLUS Project.  相似文献   
10.
Dose-dependent, amphetamine-induced reductions in protein synthesis were determined in vivo by measuring [3H]lysine incorporation into trichloroacetic acid precipitated protein in homogenates prepared from different regions of the brain or liver. Low-to-moderate doses of amphetamine (1-5 mg/kg) decreased striatal protein synthesis whereas higher doses (10 mg/kg) reduced it in the cerebral cortices, cerebellum, and remaining portions of the cerebrum, as well as in the striatum and liver. Reductions in regional brain protein synthesis occur following amphetamine treatment in relatively low doses known to change various aspects of physiology and behavior.  相似文献   
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