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BACKGROUND: Surgical revascularization employing bilateral internal mammary arteries (IMAs) is an excellent procedure in elective surgery, but its role in urgent/emergent procedures is still debating. This retrospective study evaluates the feasibility, safety and surgical early outcomes of employing double skeletonized IMAs in patients with unstable angina (UA) undergoing urgent/emergent revascularization. METHODS: From January 1997 to May 2004, 824 patients (491 males, 333 females, mean age 64 +/- 12 years) underwent urgent revascularization for UA. Bilateral IMAs were employed in 346 (42%) patients (group B) and isolated and/or saphenous vein grafts in the remaining 478 (58%) patients (group M). There were no significant differences in preoperative risk factors between the two groups (mean EuroSCORE value). RESULTS: Postoperative stay was free from complications in 87% of patients of group B and 91% of group M. In-hospital mortality (group B 5.9%, group M 5.3%, p = NS) and perioperative myocardial infarction (group B 2.2%, group M 1.96%, p = NS), mean coronary care unit stay and total hospital stay were similar in both groups. Actuarial survival at 1, 3, 5 and 7 years was respectively 98.7, 97.5, 96.9 and 96.1% in group B and 99, 93.4, 92.1 and 88.4% in group M (p < 0.05). At a mean follow-up of 6.6 years the event-free survival (p = 0.021) and reoperation-free cardiac survival (p = 0.003) were better in group B. Multivariate analysis identified that age > 65 years (p = 0.01), congestive heart failure (p = 0.001), left ventricular ejection fraction < 35% (p = 0.03), and > 1 ischemic irreversible area (p = 0.02) are negative predictors for reoperation-free cardiac survival. The employment of the left IMA (p = 0.006) and of both IMAs (p = 0.001) were positive predictors for the overall survival and reoperation-free cardiac survival. CONCLUSIONS: Our results show that the use of skeletonized bilateral IMAs is associated with an acceptable risk and a lower incidence of postoperative complications in patients with UA, improving late outcomes in this group of patients.  相似文献   
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Ovarian steroids are important modulators of normal cell growth and differentiation as well as of carcinogenesis. External stimuli trigger cell surface receptors, resulting in activation of central signal transduction pathways, that are mediated by members of the mitogen-activated protein kinase (MAPK) family. These in turn, indirectly regulate cellular functions such as cell proliferation, cell cycle, and maintenance of malignant phenotype. In our in vitro study, we have investigated the effects of two synthetic estrogens on ERK 2 activation. Estrogen receptor positive cells were incubated with the synthetic estrogens, ethinylestradiol (10(-9) mol/l) and 17 beta-estradiol valerate (10(-9) mol/l), epidermal growth factor (EGF) (10 ng/ml) and the natural estrogen 17 beta-estradiol (10(-9) mol/l), for 5 min. The same experiments were repeated prior to preincubation with the antiestrogen ICI 182780. ERK 2 or the active form alone were detected by immunoblotting. A cell proliferation assay was used to study the response of cells to various treatments. Time kinetics were performed to study duration of kinase activated state. Cell incubation with EGF as well as with either natural or synthetic estrogen stimulated proliferation. ICI 182780 inhibited this effect, but only in the case of estrogen. Synthetic estrogens activated MAP kinase in a time-dependent fashion, similar to 17 beta-estradiol. The estrogen receptor antagonist ICI 182780 blocked this effect. EGF induced a more pronounced and prolonged activation, even in the presence of the antiestrogen. Ethinylestradiol as used in oral contraceptives, and 17 beta-estradiol and 17 beta-estradiol valerate as used in hormone replacement therapy, are able to activate MAP kinase. This activation was blocked by an antiestrogen.  相似文献   
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OBJECTIVES: The aim was to review our experience with the surgical repair of the anomalous origin of one pulmonary branch from the aorta (AOPA). MATERIALS AND METHOD: Between January 1991 and March 2002, eight patients with AOPA underwent surgical correction. Three patients presented isolated AOPA. Five patients presented right AOPA and three, left AOPA. Implantation of the AOPA to the main pulmonary artery was performed by: (I) direct anastomosis in two patients with left AOPA; (II) interposition of a synthetic graft in one patient with left AOPA; (III) employing an autologous pericardial patch in two patients with right AOPA; (IV) using an aortic flap in three other patients with right AOPA. The mean follow-up time was 37.7 months. RESULTS: One patient died postoperatively due to progressive heart failure unresponsive to inotropic support. Early postoperative pulmonary hypertension crisis was identified in another patient. Within 1 year after surgery, the mean residual gradient across the anastomotic site at follow-up was 14+/-8 mmHg. The patient undergoing interposition of a synthetic graft presented a residual gradient of 29 mmHg and underwent reoperation at almost 2.5 years after the first correction. The residual gradient in patients undergoing correction according to technique I was 17+/-3 mmHg, and in patients undergoing implantation of the AOPA according to techniques III or IV was 9.5+/-4.6 mmHg (P=0.11). Similarly, the Tc-99m scintigraphy demonstrated that a lower lung perfusion (the lung perfused from the respective AOPA compared with the contralateral lung) in patients undergoing AOPA implantation according to technique I was 59+/-6(%) and in patients undergoing techniques III or IV was 72+/-4.5(%) (P=0.038). At follow-up, all patients were alive. CONCLUSION: The AOPA from the aorta is a rare but important entity, necessitating a scrupulous preoperative and intraoperative evaluation. Patients presenting this anomaly may undergo correction using various surgical techniques with acceptable results. The techniques employing autologous tissues for enlarging and lengthening the AOPA seems to be associated with less restenosis at the anastomotic site, however, larger series of patients are required to confirm such outcome.  相似文献   
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BACKGROUND: The aim of this study was to investigate whether, by using the in situ right internal thoracic artery via the transverse sinus (eventually retrocaval), both the proximal and distal major branches of the circumflex system could be grafted and to evaluate the early and late outcome in these patients. METHODS: Between January 1997 and March 2002, 452 consecutive patients underwent grafting of the circumflex system with the in situ skeletonized right internal thoracic artery routed via the transverse sinus. The mean age was 62.4 +/- 10.3 years. A mean of 2.2 +/- 0.3 arterial grafts per patient were used, and 271 (60%) patients underwent total arterial myocardial revascularization. At 3 months after surgery, 86 patients (right Y or T graft) underwent echo color Doppler imaging before and after an adenosine provocative test. The mean follow-up was 27 +/- 8 months. RESULTS: The success rate of skeletonized right internal thoracic artery grafting to the circumflex system branch was 100%. There were 15 (3.4%) hospital deaths. In 116 patients who underwent postoperative angiography, the total patency rates of the right and left internal thoracic arteries were 94% and 96.6%, respectively. Strong predictors for nonfunctional internal thoracic artery grafts were a small internal thoracic artery caliber (P <.001), recipient coronary artery diameter less than 1.5 mm (P =.012), stenotic lesions of less than 60% (P =.016), and diffuse stenotic lesions (P =.015) of the recipient coronary artery. In 86 patients who underwent postoperative echo color Doppler imaging, the flow reserves at the main stem of the left and right internal thoracic arteries were 2.24 +/- 0.5 and 2.48 +/- 0.6, respectively. Cumulative actuarial survival at 3 years was 96.3%, and event-free cumulative survival was 93%. The Cox model revealed a left ventricular ejection fraction of less than 35% (P =.016), age greater than 70 years (P =.025), New York Heart Association grade greater than III (P =.0019), nontotal arterial myocardial revascularization (P =.002), and the preoperative presence of more than 1 ischemic area (P <.001) as strong predictors for poor overall cumulative event-free survival. CONCLUSIONS: The skeletonized right internal thoracic artery, placed via the transverse sinus and eventually retrocaval, can reach most branches of the circumflex system and is associated with an excellent patency rate. The predictors for poor overall event-free survival seem to be similar to those of the general population undergoing conventional coronary artery bypass grafting. Use of bilateral internal thoracic arteries and in situ right internal thoracic artery grafting via the transverse sinus offers the possibility of various configuration constructions, making possible total arterial myocardial revascularization with a minimum number of arterial conduits.  相似文献   
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OBJECTIVES: To evaluate in a cohort of ESCAD patients (pts) the effects of on-pump/beating-heart versus conventional CABG in terms of early and mid-term survival and morbidity and LV function improvement. METHODS: Between January 1993 and December 2000, 78 (Group I) ESCAD pts underwent on-pump/beating-heart surgery. Mean age in Group I was 66.2+/-6 (58-79), NYHA and CCS class were 3.2+/-0.6 and 3.3+/-0.4 respectively, Myocardial viability index 0.69+/-0.1 (%), LVEF (%) 24.8+/-4, LVEDP (mmHg) 28.1+/-5.8 and LVEDD(mm) 69.5+/-6. Group II consisted in 78 ESCAD patients undergoing conventional CABG selected in a randomized fashion from an age, sex, and LVEF corrected group of patients. Mean age in Group II was 65.7+/-5 (57-78), NYHA 3.1+/-0.7, CCS 3.4+/-0.8, LVEF(%) 25+/-5, LVEDP(mmHg) 27.9+/-4.4 and LVEDD(mm) 69.2+/-7.2. RESULTS: Postoperatively, 5(7.7%) patients died in Group I versus 7(11.5%) patients in Group II (P>0.1). CPB time resulted to be in Group II patients (P=0.001) and the mean distal anastomoses per patient was similar between groups (P=Ns). Perioperative AMI (P=0.039), LCOS (P=0.002), necessity for ultrafiltration (P=0.018) and bleeding>1000 ml (P=0.029) were significantly higher in Group II. None of the Group I patients underwent surgical revision for bleeding versus 8(10.3%) patients in Group II (P=0.011). At 6 months after surgery, the LV function improved significantly in Group I patients, demonstrated by an increased LVEF=27.2+/-4(%)(P=0.001), lower LVEDP=26.4+/-3(mmHg)(P=0.029) and LVEDD=67+/-4(mm) (P=0.004) instead of a lower LVEDD=66.8+/-6(mm)(P=0.032) versus the preoperative data in Group II. The actuarial survival at 1, 3 and 5 yr were 90, 82 and 71% in Group I and 89, 83 and 74% in Group II (P=Ns). CONCLUSION: In ESCAD patients who may poorly tolerate cardioplegic arrest, on-pump/beating-heart CABG may be an acceptable alternative associated with lower postoperative mortality and morbidity. Such a technique offers a better myocardial and renal protection associated with lower postoperative complications due to intraoperative hypoperfusion.  相似文献   
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BACKGROUND AND AIMS OF THE STUDY: The study aims were to evaluate early and mid-term survival and freedom from reoperation in patients with isolated mitral valve (MV) congenital malformation (MVCM) or in association with other cardiac defects, and to identify predictors for poor early and late outcome. METHODS: Between January 1990 and February 2001, 58 children with MVCM underwent MV-conserving surgery; patients were allocated to group I (n = 21) with isolated MVCM, and group II (n = 37) with MVCM and associated congenital heart defects (ACHD). MV stenosis was identified in 10 (48%) group I patients, and 11 (30%) group II patients (p = NS); MV insufficiency was present in 11 (52%) patients in group I, and in 26 (70%) of group II (p = NS). The most frequently found MVCM were annular dilatation (n = 13) cases and elongated chordae (n = 14). Hammock MV was found in nine patients (15%). RESULTS: Six (10%) hospital deaths occurred. Mortality was 5% (n = 1) in group I, and 13% (n = 5) in group II (p = 0.4). Mean repair techniques per patient was 2.05+/-0.4 and 2.3+/-0.3 in groups I and II respectively (p = 0.009). Mechanical ventilation time was 2.1+/-1 and 2.8+/-0.7 days in groups I and II (p = 0.003). The incidence of postoperative mitral regurgitation grade > or =1 was significantly higher in group II (p = 0.008). At five-year follow up, actuarial survival was 91.5% in group I and 86% in group II (p = 0.037). Actuarial reoperation-free survival was 85% in group I and 73% in group II (p = 0.01). Multivariate analysis showed age >12 months (p = 0.033), hammock MV (p = 0.0088) and ACHD (p = 0.0048) were strong predictors for poor event-free survival. CONCLUSION: MV repair for MVCM provides acceptable early and mid-term outcome in terms of mortality and freedom from reoperation. ACHD significantly reduce early and late postoperative survival and freedom from reoperation.  相似文献   
110.
OBJECTIVE: To determine whether alterations in the secretion and regulation of matrix metalloproteinases (MMPs) and their inhibitors are present in uterine endometrial cells from endometriosis patients. STUDY DESIGN: In an in vitro study, uterine endometrial cells from 19 regularly cycling women with and 32 without endometriosis were treated with diethyl stilbestrol, promegestone (R5020), interleukin-1 (IL-1) and tumor necrosis factor a (TNF-alpha). Culture supernatants were assayed for MMPs 1, 2, 3, and 9, and for tissue inhibitors of MMP (TIMP-1 and TIMP-2) by ELISA. RESULTS: MMP-3 was secreted in high concentrations, moderate concentrations were seen for MMP-1 and MMP-2, and very low concentrations for MMP-9. Substantially more TIMP-1 than TIMP-2 was secreted. MMP-1 and MMP-3 were uniformly attenuated by R5020, while MMP-2 was not influenced by hormone treatment. MMP-3 was upregulated by TNF-alpha in all samples while IL-1 only increased secretion in cells from endometriosis patients. CONCLUSION: The upregulation of MMP-3 by IL-1 may contribute to an increased invasiveness of uterine endometrial fragments in endometriosis patients.  相似文献   
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