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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   

3.
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   
4.
BACKGROUND: The COL4A3-COL4A4-COL4A5 network in the glomerular basement membrane is affected in the inherited renal disorder Alport's syndrome (AS). Approximately 85% of the AS patients are expected to carry a mutation in the X-chromosomal COL4A5 gene and 15% in the autosomal COL4A3 and COL4A4 genes. The COL4A5 chain is also present in the epidermal basement membrane (EBM). It is predicted that approximately 70% of the COL4A5 mutations prevent incorporation of this chain in basement membranes. METHODS: We investigated whether or not COL4A5 defects could be detected by immunohistochemical analysis of the EBM. Punch skin biopsies were obtained from 22 patients out of 17 families and two biopsy specimens from healthy males were used as controls. RESULTS: In four cases with the COL4A5 frameshift or missense mutations, the COL4A5 chain was either lacking from the EBM (male) or showed a focally negative pattern (female). In three other patients with a COL4A5 missense mutation, a COL4A3 and a COL4A4 mutation, respectively, the COL4A5 staining was normal. A (focally) negative EBM-COL4A5 staining was found in three patients of six families with a diagnosis of AS and in one family of a group of four families with possible AS. CONCLUSIONS: The (focal) absence of COL4A5 in the EBM of skin biopsy specimens can be used for fast identification of COL4A5 defects. Combined with polymorphic COL4A5 markers, both postnatal and prenatal DNA diagnosis are possible in the family of the patient.  相似文献   
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A group of 390 patients with mild angina pectoris or myocardial infarction without subsequent angina had early coronary bypass operation. Five year survival was significantly higher (95.4%) than in a similarly selected medically treated group (88.5%) reported before. One death occurred in the 30 day postoperative period. Five year survival in the 179 patients who had internal mammary artery grafts was 98.9%. Survival for patients with mild angina and satisfactory left ventricular function (96.2%) was significantly higher than in the medical subset (91.3%). In the patient population studied, five year survival was higher in patients who had early bypass operations than in those who did not.  相似文献   
8.
Frank lead electrocardiograms were recorded from 149 normal and abnormal adult males using four different electrode placements. All chest electrodes were placed at: (1) the fourth intercostal space level, (2) the fifth intercostal space level, (3) the fourth intercostal space level with V4 substituted for C, and (4) the fifth intercostal space level with V4 substituted for C.Differences in mean values of many commonly used amplitudes and orientations were not statistically significant among the four recording methods, but amplitude differences for individual subjects were often large and difficult to predict. When V4 is substituted for C, as commonly done in some laboratories, Rx decreased and Rz increased by more than 10 per cent in about 40 per cent of the cases. In about 70 per cent of the cases, Rx and Rz changed significantly when electrode level was shifted from the fifth to the fourth intercostal space. For these 70 per cent, it does not appear possible to accurately predict increase or decrease of Rx, Rz, or QRSm.Analysis programs which depend on individual amplitude measurements are likely to be significantly affected by electrode placement. It is suggested that criteria for analysis programs developed using a specified version of the Frank system should ideally be applied only to electrocardiograms recorded in the same manner.  相似文献   
9.
Five hundred consecutive patients underwent aortic valve replacement and coronary revascularization in the years from 1967 to 1981, with 29 (5.9%) in-hospital deaths. Current operative mortality (1978-1981) is 3.4%. Univariate and multivariate analyses were used to identify determinants of early and late risk. Female sex, aortic insufficiency, and advanced age increased in-hospital mortality, whereas use of cardioplegia decreased it. At follow-up of 471 patients who survived hospitalization for 1 to 135 months (mean 41) after surgery, 96 late deaths were documented. Survival rates were 87%, 80%, and 55%, and event-free survival rates were 80%, 65%, and 39% at 2, 5, and 10 years after surgery, respectively. The late survival rate was unfavorably influenced by the presence of moderately or severely impaired left ventricular function and double-vessel coronary disease; the rate was enhanced for patients in age group from 50 to 59 years old and was not influenced by the method of myocardial protection. The event-free survival rate decreased with the presence of moderately or severely impaired left ventricular function and was enhanced for patients with New York Heart Association class I or II symptoms before surgery. Patients with bioprostheses who did not receive anticoagulants had higher survival and event-free survival rates than did either patients with bioprostheses who received anticoagulants or patients with mechanical valves, whether they received anticoagulants or not.  相似文献   
10.
BACKGROUND: In the era of cost containment, cost analysis should demonstrate the cost-effectiveness of new anesthetic drugs. METHODS: This single-blind, prospective, randomized study compared the costs of three remifentanil (REM)-based anesthetic techniques with a conventional one in 120 patients undergoing otorhinolaryngeal surgery. The patients were randomized (n=30 each group) to either receive a combination of REM with propofol, desflurane or sevoflurane, or a conventional anesthetic with thiopentone, alfentanil, isoflurane and N2O. RESULTS: The costs for anesthetic and nonanesthetic drugs and for disposables were twice as high in the three REM-based groups as in the conventional group (REM/PRO 0.51 Euro;/min, REM/DES 0.42 Euro;/min, and REM/SEVO 0.41 Euro;/min vs. 0.18 Euro;/min in the ALF/ISO/N2O group; P<0.05). Wastage of intravenous drugs accounted for up to 40% of total costs. In all REM groups, early recovery was predictably faster and more complete (P<0.05). Patient satisfaction was equally high (90-97%) in all groups, with less nausea in the REM/PRO group. CONCLUSION: This study demonstrates that REM-based anesthetic techniques are more expensive than a conventional technique using alfentanil, isoflurane and N2O. This is the result of higher costs of anesthetic and nonanesthetic drugs and of disposables. The wastage of intravenous drugs contributes considerably to these costs.  相似文献   
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