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Real time two-dimensional transthoracic and transesophageal echocardiography demonstrated a mobile echolucent mass attached to the pulmonary valve in a 25-year-old adult, 20 years following balloon pulmonary valvuloplasty. The mass was surgically excised and pathology showed it to be a cyst.  相似文献   
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Background. The use of two internal mammary artery grafts in coronary artery bypass grafting has been associated with decreased risks of death, reoperation, and angioplasty. However, bilateral internal mammary artery takedown is associated with higher incidence of sternal wound infection, particularly in people with diabetes and in elderly and obese patients. This study was conducted to explore the feasibility of using right internal mammary artery (RIMA) and radial artery (RA) as a composite graft while preserving the distal two thirds of the RIMA to leave the sternal blood supply intact.

Methods. Eighteen patients underwent coronary artery bypass grafting using proximal RIMA and RA composite graft as one of the bypass conduits. The distal two thirds of the RIMA was left intact to preserve sternal blood supply. The graft-free flows of the RIMA and RA composite graft and of the left internal mammary artery graft and the length of the composite graft had been measured. The graft patency and the flow in the distal part of the unharvested RIMA was evaluated postoperatively 2 weeks after the procedure. In 6 of these patients the graft patency was evaluated by selective angiography.

Results. There was no hospital mortality or incidence of perioperative myocardial infarction. None of the patients needed intraaortic balloon pump support postoperatively. There was no sternal wound infection. The vessels grafted were distal right coronary artery (n = 7), posterior descending artery (n = 8), obtuse marginal branches (n = 3), and posterolateral ventricular branch (n = 1); 1 patient received the composite graft as a sequential graft to the posterior descending artery and posterolateral left ventricular branches. The mean graft-free flow of the RIMA and RA composite graft was 98.06 ± 16.93 mL/min compared to left internal mammary artery flows of 55.80 ± 8.99 mL/min. All 16 patients who had a good echo window showed patent grafts when evaluated by two-dimensional echocardiography and color Doppler echocardiography. All of the 6 patients in whom the angiogram was repeated postoperatively showed patent RIMA and RA grafts.

Conclusions. Myocardial revascularization using proximal RIMA and RA in situ pedicle graft was safe in patients with diabetes and in obese and chronic obstructive pulmonary disease patients. This graft was useful to revascularize posterior descending artery, posterolateral ventricular branches of right coronary artery, and obtuse marginal branches where a left internal mammary artery and RA composite graft cannot be used because of technical reasons. Its usage was not associated with sternal wound infection.  相似文献   

25.
Venu KM  Koka R  Garikipati R  Shenava Y  Madhu TS 《Injury》2001,32(5):395-400
We present a retrospective review of 13 patients with periprosthetic femoral fractures treated with the Dall-Miles cable and plate fixation system between 1995 and 1999. Of these, 12 fractures were in relation to hip arthroplasty and one was proximal to the femoral component of a total knee replacement. Mean age at presentation was 77 years (range 66-87) with the male female ratio of 6:7. All patients were followed up until there was evidence of clinical and radiological union. The average follow-up period was 6.5 months (range 2.5-24). We achieved satisfactory results in ten patients with average time to union of 4.4 months. The results were unsatisfactory in three patients who required further revision procedures due to failure of fixation or non-union. Internal fixation of the fracture with the loose femoral component left in-situ led to failure of union in one patient. Varus mal-alignment of the femoral component to the shaft of more than 6 degrees was associated with unsatisfactory outcome in two patients. The Dall-Miles cable and plate system is a useful method of internal fixation for majority of periprosthetic femoral fractures. This method may not be suitable if the femoral component is loose or if it is in varus angulation of more than 6 degrees to the shaft of the femur.  相似文献   
26.
The use of the radial artery (RA) as a coronary artery bypass graft has assumed a revival and thus a multitude of issues have arisen surrounding the routine and widespread use of this conduit in myocardial revascularization. There has been no uniformity regarding harvest techniques, assessment of the adequacy of hand collateral circulation, antispasm protocols, selection of target vessels, and the site of proximal anastomosis. It is widely believed and practiced that the RA should be harvested as a pedicle graft and preferably be used to bypass critically stenosed (>70% stenosis) coronary arteries. It is used either as a free graft with proximal anastomosis to the ascending aorta or as a composite arterial graft along with the left or right internal thoracic artery. The patency of RA grafts depends on the severity of the target coronary artery stenosis and target artery location rather than its use as an aortocoronary conduit or composite graft. In this article, we reviewed the current knowledge regarding the use of RA grafts as a coronary bypass conduit in an attempt to suggest a few acceptable strategies concerning the above issues in a given clinical scenario.  相似文献   
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PURPOSE: To correlate pulmonary artery catheterization (PAC) use and 30-day outcomes and to characterize the use of pulmonary artery catheters among patients with acute coronary syndromes (ACS). SUBJECTS AND METHODS: We retrospectively studied 26437 ACS patients from two large multicenter, international randomized clinical trials. Multivariable and causal inference analyses were applied to adjust for differences in baseline risk. RESULTS: PAC was performed in 735 patients (2.8%), with a median time to insertion of 24 hours. Patients undergoing PAC were older (median, 67 vs. 64 years), more often diabetic (25.7% vs.16.2%), and more likely to present with ST-segment elevation (81.6% vs. 70.2%) or Killip class III or IV (7.9% vs. 1.4%). US patients were 3.8 times more likely than non-US patients to undergo PAC. Patients managed with PAC also underwent more procedures, including percutaneous intervention (40.7% vs. 18.1%), coronary artery bypass grafting (12.5% vs. 7.7%), and endotracheal intubation (29.3% vs. 2.2%). Mortality at 30 days was substantially higher among patients with PAC for both unadjusted (odds ratio [OR] 8.7; 95% confidence interval [CI] 7.3-10.2) and adjusted analyses (OR 6.4; 95% CI 5.4-7.6) in all groups except in patients with cardiogenic shock (OR 0.99; 95% CI 0.80-1.23). CONCLUSIONS: PAC was associated with increased mortality, both before and after adjustment for baseline patient differences and subsequent events that may have led to PAC use, except in patients with cardiogenic shock. The definitive role of PAC in managing patients with ACS is still to be determined.  相似文献   
29.
OBJECTIVE: To examine the incidence of postoperative bleeding after coblation and noncoblation tonsillectomy and to use postoperative bleeding as an outcome measure to determine the presence of a learning curve with this new surgical technique. STUDY DESIGN: A retrospective review of records from January 1999 to April 2003 to determine type of tonsillectomy performed and the presence of postoperative bleeding. A chi-square analysis was used to determine a statistical difference between the postoperative bleed rate of coblation and noncoblation procedures. The examined time period was divided into 3-month intervals, and the coblation postoperative bleeds were tallied for each interval. The Cochraine-Armitage test of linear trend was used to assess change in the postoperative bleeds. RESULTS: One thousand seven hundred sixty-two tonsillectomies were performed. The postoperative bleed rate for noncoblation tonsillectomy was 6.1% (74/1,216). The bleeding rate for coblation tonsillotomy was 5.9% (18/303) and 5.4% (13/239) for coblation tonsillectomy. There was no statistical difference (P = .93) between bleed rates for coblation versus noncoblation techniques. There was no difference in the need for operative intervention to control postoperative bleeding: 16.2% (12/74) for noncoblation technique and 25.85 (8/31) for coblation procedures (P = .25). The postoperative coblation bleed rates for the 3-month periods did not reveal an increasing or decreasing trend in the postoperative bleed rate (P = .49). CONCLUSION: Coblation is a safe procedure for performing tonsil surgery with no significant difference in postoperative bleeding from previous techniques and no increased need for operative intervention to control postoperative bleeding. A learning curve could not be identified when using postoperative bleeding as an outcome measure for coblation tonsillectomy.  相似文献   
30.
A method that considerably reduces the computational and memory complexities associated with the generation of high-dimensional (≥3) feature maps for image segmentation is described. The method is based on the K-nearest neighbor (KNN) classification and consists of two parts: preprocessing of feature space and fast KNN. This technique is implemented on a PC and applied for generating 3D and 4D feature maps for segmenting MR brain images of multiple sclerosis patients.  相似文献   
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