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71.
OBJECTIVE: Truncal valve regurgitation and interrupted aortic arch have frequently been identified as risk factors in the repair of truncus arteriosus. We wished to examine these factors in the current era including the impact of truncal valve repair. METHODS: Between January 1992 and August 1998, 50 patients underwent surgical repair of truncus arteriosus. Their ages ranged from 2 days to 6 months (median, 2 weeks). Nine patients had associated interrupted aortic arch. Of the 14 patients (28%) in whom truncal valve regurgitation was diagnosed preoperatively, 5 had mild regurgitation, 5 had moderate regurgitation, and 4 had severe regurgitation. Five underwent truncal valve repair and 1 underwent homograft replacement of the truncal valve with coronary reimplantation. RESULTS: The actuarial survival was 96% at 30 days, 1 year, and 3 years. There were no deaths in patients with associated interrupted aortic arch. The 2 deaths in the series occurred in patients with truncal valve regurgitation, neither of whom underwent repair. Postoperative transthoracic echocardiography in patients who underwent valve repair showed minimal residual valvular regurgitation. None of the patients has required reoperation because of truncal valve problems or aortic arch stenosis at a median follow-up of 23 months (range, 1-60 months). Conduit replacement has been done in 17 patients (34%) after a mean duration of 2 years. The freedom from reoperation for those who had an aortic homograft was 4 years and for those who had a pulmonary homograft was 3 years. CONCLUSION: Despite the magnitude of the operation, excellent results can be achieved in complex forms of truncus arteriosus. In the current era interrupted aortic arch is no longer a risk factor for repair of truncus. Aggressive application of truncal valvuloplasty methods should neutralize the traditional risk factor of truncal valve regurgitation.  相似文献   
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PURPOSE: Knowledge of the functional anatomy, hemodynamics, neurophysiology and pharmacology of penile erection has improved tremendously during the last 2 decades. However, only few in vivo studies on human peripheral neurotransmission have been carried out up until now. Therefore, we conducted a study to examine plasma levels of catecholamines norepinephrine (NE) and epinephrine (E) in the peripheral and cavernous blood of healthy men during penile flaccidity and in different phases of erection. MATERIALS AND METHODS: Blood samples were drawn simultaneously from the corpus cavernosum (CC) and the cubital vein (P) in 53 healthy volunteers with normal erectile function, in four different functional states of the cavernous erectile tissue (flaccidity = 1, tumescence = 2, rigidity = 3, detumescence = 4). Penile erections were induced by audiovisual and tactile stimulation and the plasma concentrations of NE and E were determined by means of a radioimmunoassay (RIA). RESULTS: A significant (p <0.001) reduction of NE in CC plasma was found from flaccidity (362 + or - 173 pg./ml.) to rigidity (248 + or - 122 pg./ml.), followed by an increase in the detumescence phase (336 + or - 199 pg./ml.), (p <0.001). In contrast, changes in NE levels in the peripheral plasma were less pronounced from 1P (202 + or - 102 pg./ml.) to 3P (229 + or - 118 pg./ml.), (p = 0.006) and from 3P to 4P (222 + or - 127 pg./ml.), respectively (p = 0.370). The most pronounced increase in cavernous E levels were observed from flaccidity (47 + or - 41 pg. /ml.) to tumescence (130 + or - 106 pg./ml.) (p <0.001). Cavernous E levels dropped significantly from 113 + or - 67 pg./ml. during rigidity to 76 + or - 57 pg./ml. + or - during detumescence (p <0.001). The course of peripheral plasma levels of E was similar to that in the cavernous blood. Mean peripheral E level was 69 + or - 55 pg./ml. in the state of penile flaccidity, reaching 98 + or - 78 pg./ml. in tumescence and 82 + or - 64 pg./ml. in rigidity (p <0.001), respectively, and finally decreasing to 62 + or - 46 pg./ml. in detumescence. CONCLUSION: Penile erection, based on the relaxation of cavernous and arterial smooth muscle, is accompanied by a significant reduction of NE in cavernous blood, while E levels rose in peripheral and cavernous blood during developing erection.  相似文献   
74.
OBJECTIVE: A number of patients with Williams syndrome or other forms of elastin arteriopathy have stenoses of pulmonary arteries in addition to supravalvular aortic stenosis. We sought to investigate the effect of the degree of pulmonary arterial stenosis on the prognosis after an operation for supravalvular aortic stenosis to help define the optimal treatment strategy for patients with severe forms of elastin arteriopathy. METHODS: Between 1960 and 1999, 33 patients underwent operations for supravalvular aortic stenosis while having significant stenoses of the pulmonary arteries. We retrospectively reviewed patient charts, obtained current follow-up information, and determined risk factors for survival and reoperation. RESULTS: Fifteen patients with moderate right-sided obstructions (confirmed by pulmonary artery Z-scores and right ventricular/descending aortic pressure ratio) underwent operations for supravalvular aortic stenosis only. Eighteen patients had more severe right-sided obstructions and underwent surgical relief of pulmonary arterial stenoses or right ventricular outflow tract obstruction in addition to operations for supravalvular aortic stenosis. Eight patients had undergone preoperative balloon dilations of stenotic pulmonary arteries. There were 6 early deaths and 1 late death in our series. Survival at 10 and 20 years was 76% (70% confidence interval, 68%-84%) and freedom from reintervention was 59% (70% confidence interval, 46%-71%) at 10 years and 49% (70% confidence interval, 35%-62%) at 20 years. Multivariate analysis revealed that patients with a right ventricular/descending aortic pressure ratio of 1.0 or more were at higher risk for reintervention but not for death. CONCLUSIONS: Surgical treatment of pulmonary artery obstructions in elastin arteriopathy is palliative but, in conjunction with balloon dilation of peripheral pulmonary arteries, offers good long-term survival to patients with the severest form of elastin arteriopathy.  相似文献   
75.
OBJECTIVE: Our purpose was to describe the outcome of the Rastelli repair in D -transposition of the great arteries and to determine the risk factors associated with unfavorable events. METHODS: From March 1973 to April 1998, 101 patients with D -transposition of the great arteries and ventricular septal defect underwent a Rastelli type of repair. Median age and weight were 3.1 years (10th to 90th percentiles 0.3-9.9 years) and 12.8 kg (5.9-28.2). Pulmonary stenosis was present in 73 patients and pulmonary atresia in 18; 10 patients had no left ventricular outflow tract obstruction. RESULTS: There were 7 early deaths (7%) and no operative deaths in the last 7 years of the study. Risk factors for early death, by univariable analysis, included straddling tricuspid valve (P =.04) and longer aortic crossclamping times (P =.04). At a median follow-up of 8.5 years, there were 17 late deaths and 1 patient had undergone heart transplantation. Forty-four patients had reoperations for conduit stenosis, 11 for left ventricular outflow tract obstruction, and 28 had interventional catheterization to relieve conduit stenosis. Nine patients had late arrhythmias, and there were 5 sudden deaths. Overall freedom from death or transplantation (Kaplan-Meier) was 82%, 80%, 68%, and 52% at 5, 10, 15, and 20 years, respectively. Freedom from death or reintervention (catheterization or surgical treatment) was 53%, 24%, and 21% at 5, 10, and 15 years of follow-up, respectively. CONCLUSIONS: The Rastelli repair can be performed with low early mortality. However, substantial late morbidity and mortality are associated with conduit obstruction, left ventricular outflow tract obstruction, and arrhythmia.  相似文献   
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BACKGROUND: From May 1996 to August 1998 a minimal access approach was used for 135 of 200 consecutive surgical atrial septal defects closures in children through young adults ranging in age from 6 months to 25 years (median 5 years). METHODS: A 3.5- to 5-cm midline incision was centered over the xiphoid with division of the xiphoid alone (transxiphoid) or of the lower sternum (ministernotomy); both groups underwent bicaval venous cannulation through the incision. Cardioplegia and aortic cross-clamping were administered through the incision. Cephalad retraction of the sternum with a fixed-arm retractor aided exposure. RESULTS: There have been no early or late deaths and no bleeding or wound complications. No procedure required conversion to a full sternotomy, and no cannulation attempt was abandoned for an alternate site. Cross-clamp and cardiopulmonary bypass times were equivalent to those in the full sternotomy group. The mean length of hospital stay in the ministernotomy group was 2.7 days. CONCLUSIONS: The closure of atrial septal defects can be performed through a transxiphoid or ministernotomy approach, conferring a satisfactory cosmetic result without compromising the safety or accuracy of the repair.  相似文献   
78.
Supplementation with antioxidant vitamins has been associated with decreased risk of stomach cancer or regression of precancerous lesions in high-risk areas of China and Colombia. We examined the association between stomach cancer mortality and regular use (> or =15 times per month) of individual vitamin C supplements, individual vitamin E supplements, and multivitamins among 1,045,923 United States adults in the Cancer Prevention Study II (CPS-II) cohort. CPS-II participants completed a questionnaire at enrollment in 1982 and were followed for mortality through 1998. During follow-up, there were 1,725 stomach cancer deaths (1,127 in men and 598 in women). After adjustment for multiple potential stomach cancer risk factors, vitamin C use at enrollment was associated with reduced risk of stomach cancer mortality [rate ratio (RR), 0.83; 95% confidence interval (CI), 0.68-1.01]. However, this reduction in risk was observed only among participants with short duration use at enrollment (RR, 0.68; 95% CI, 0.51-0.91 for <10 years of use; RR, 1.00; 95% CI, 0.73-1.38 for > or =10 years of use). There was no association between stomach cancer mortality and regular use of vitamin E (RR, 1.02; 95% CI, 0.82-1.27) or multivitamins (RR, 0.89; 95% CI, 0.77-1.03), regardless of duration of use. Our results suggest that the use of vitamin C, vitamin E, or multivitamin supplements may not substantially reduce risk of stomach cancer mortality in North American populations in which stomach cancer rates are relatively low. Our results do not rule out effects of vitamin supplementation in areas in which stomach cancer rates are high and stomach cancer etiology may differ.  相似文献   
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