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Simula DV Edwards WD Tazelaar HD Connolly HM Schaff HV 《Mayo Clinic proceedings. Mayo Clinic》2002,77(2):139-147
OBJECTIVE: To quantitate the pathologic features of carcinoid plaques in a relatively large number of surgical specimens from a single institution. PATIENTS AND METHODS: Medical records, operative reports, and surgical specimens were reviewed from all patients with carcinoid heart disease who underwent cardiac valvular surgery at Mayo Clinic, Rochester, Minn, between 1980 and 2000. RESULTS: The study group included 75 patients (45 men, 30 women) who ranged in age from 26 to 78 years (mean, 59 years). From these 75 patients, 139 valves had been excised surgically (73 tricuspid, 55 pulmonary, 6 mitral, 5 aortic). Pure regurgitation was the most common dysfunctional state of the tricuspid valve (80% [60/75]), mitral valve (97% [32/33]), and aortic valve (96% [23/24]). The pulmonary valve was more often both stenotic and insufficient (52% [37/71]) than purely regurgitant (30% [21/71]). In all cases, valve dysfunction was attributed to the presence of carcinoid plaques, which caused both thickening and retraction. Thickening was the result of both cellular proliferation and deposition of extracellular matrix. Proliferation of myofibroblasts was observed in all plaques and was mild in 49% (68/139) and moderate or severe in 51% (71/139). Extracellular matrix included collagen (in 99% of the 139 valves), myxoid ground substance (98% [136/139]), and elastin (20% [28/139]). Carcinoid plaques were also involved by neovascularization (94% [131/139]), chronic inflammation (94% [131/139]), and mast cell infiltration (64% [89/139]). Severe thickening was attributable primarily to collagen deposition in tricuspid valves and to myofibroblast proliferation and myxoid matrix in pulmonary valves. CONCLUSIONS: Among patients undergoing valvular surgery for carcinoid heart disease, tricuspid and pulmonary valves represented 92% of the excised valves (128/ 139). Although numerous cellular and extracellular features were common to the carcinoid plaques, variability in their relative expression produced appreciable differences in the histologic appearance among the plaques. 相似文献
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Dearani JA Danielson GK Puga FJ Schaff HV Warnes CW Driscoll DJ Schleck CD Ilstrup DM 《The Annals of thoracic surgery》2003,75(2):399-410; discussion 410-1
BACKGROUND: Pulmonary ventricle (PV) to pulmonary artery (PA) conduits have made possible the correction of many complex congenital cardiac anomalies. METHODS: Between April 1964 and January 2001, 1270 patients underwent operation with conduit placement from the PV to PA. The present study evaluates late outcome of 1095 patients (612 males, 483 females) having an operation before July 1992. Mean age was 9.6 +/- 8.2 years old. Diagnoses included pulmonary atresia/tetralogy of Fallot (459), transposition of the great arteries (TGA) (232), truncus arteriosus (193), double outlet right ventricle (DORV) (121), corrected TGA (49), septated univentricular heart (36), and other (5). A porcine-valved Dacron conduit was used in 730, homograft in 239, and non-valved conduit in 126. RESULTS: Early mortality decreased from 23.5% prior to 1980 to 3.7% for the most recent decade. Mean follow-up was 10.9 years (maximum, 29 years). Actuarial survival for early survivors at 10 and 20 years was 77.0% +/- 1.5% and 59.5% +/- 2.6%. On univariate analysis, clinical and hemodynamic factors associated with late mortality were male gender, older age at operation, higher post-repair PV/systemic ventricle (SV) pressure ratio, higher distal PA pressure, and longer bypass time (p < or = 0.01 for all). On multivariate analysis, independent risk factors for late mortality were male gender, older age at operation, diagnosis of TGA, corrected TGA, truncus, or univentricular heart, and PV/SV pressure ratio > or = 0.72 (p < or = 0.03 for all). Freedom from reoperation for conduit failure at 10 and 20 years was 55.5% +/- 2.0% and 31.9% +/- 2.7%. On multivariate analysis, independent risk factors for conduit failure were homograft conduit, diagnosis of TGA, younger age at operation, and smaller conduit size (p < or = 0.007 for all). Reoperation for one conduit replacement was performed in 306 patients, two conduit replacements in 55 patients, three in 6 patients, and four in 3 patients. Overall early mortality for conduit replacement in this series was 4.9%; it was 1.7% for patients operated on from 1989 through 1992. At follow-up, 84% of survivors were in NYHA class I or II. CONCLUSIONS: Operations that include conduit placement and replacement can be performed with low early mortality. Younger age at operation was associated with improved late survival. The diagnosis of TGA was associated with increased risk for conduit failure, and the durability of the homograft, in this series, was inferior to the porcine-valved Dacron conduit. Quality of life was excellent for most patients despite the need for reoperation. 相似文献
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Oliver WC Nuttall GA Ereth MH Santrach PJ Buda DA Schaff HV 《Journal of cardiothoracic and vascular anesthesia》2003,17(2):165-170
OBJECTIVE: To assess the effect of heparin-coated circuits on bleeding, transfusion, and platelet count in patients undergoing primary coronary artery bypass grafting with full heparinization. DESIGN: Randomized, double-blind study. SETTING: Tertiary-care academic medical center. PARTICIPANTS: Eighty-eight patients undergoing coronary artery bypass grafting requiring cardiopulmonary bypass (CPB) without previous sternotomy. INTERVENTIONS: Subjects received either a heparin-coated or an uncoated extracorporeal circuit for CPB. Heparin, 300 micro/kg, was administered, and supplemental amounts were administered to maintain an activated coagulation time of greater than 480 seconds. Platelet counts were determined during CPB. Mediastinal chest tube drainage was collected in the intensive care unit for 24 hours. MEASUREMENTS AND MAIN RESULTS: The mean platelet counts were similar between the groups during CPB. There was no significant difference in 24-hour mediastinal chest tube drainage (mean +/- standard deviation; median) between the heparin-coated (n = 44, 1096 +/- 401, 1015 mL) and uncoated group (n = 44, 1150 +/- 548, 1040 mL; p = 0.91). The heparin-coated group received less allogeneic packed red blood cells (0.9 +/- 1.6, 0.0 v 1.5 +/- 1.8, 1.0 U; p = 0.04). CONCLUSIONS: The use of a heparin-coated or uncoated cardiopulmonary bypass circuit and full heparinization marginally reduced only red blood cell transfusion but was not associated with platelet sparing or reduced perioperative bleeding. 相似文献
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The authors present a case of a papillary type renal cell carcinoma. The tumor is mostly discovered accidentally; a histopathological evaluation is indispensable for an exact diagnosis. Because of a better prognosis, differentiation of this tumor type from the classic variant of renal cell carcinoma is necessary, however, the contralateral appearance of a second tumor is not to be excluded, which necessitates a strict patient follow-up. Prevalence of this tumor is higher in patients with chronic dialysis. 相似文献
58.
Englberger L Carrel T Schaff HV Kennard ED Holubkov R;AVERT Investigators 《The Journal of heart valve disease》2001,10(5):562-571
BACKGROUND AND AIM OF THE STUDY: Differences in heart valve procedures between North American (NA) and European (EU) centers were evaluated in a multicenter trial. METHODS: Between July 1998 and January 2000, 807 patients from 12 NA (n = 446) and seven EU centers (n = 361) were randomized to receive either Silzone or conventional valves in the Artificial Valve Endocarditis Reduction Trial (AVERT). Subanalysis was performed to compare demographics, patient risk profile, surgical techniques and perioperative management of patients in NA and EU centers. RESULTS: Mean age was significantly younger and body mass index higher in NA. Patients' risk profiles showed significantly higher incidences of previous myocardial infarction, congestive heart failure, angina, prior cardiovascular surgery, and history of smoking in NA. A different distribution of implant position was observed between groups: aortic valve/mitral valve/double valve replacement in 54.0, 35.7 and 10.3% in NA, and 64.5, 27.4 and 8.0% in EU (p <0.01). Concomitant coronary artery bypass grafting was performed in 31.6% of NA patients and 19.4% of EU patients (p <0.001). Timing of surgery showed a higher incidence of urgent procedures in NA centers. Distribution of valve sizes and perioperative complication rate were similar, but length of hospital stay was longer in EU centers. CONCLUSION: Surprisingly, surgeons in NA and EU centers are faced by different patient populations requiring mechanical heart valve replacement. NA patients were younger, but required more extensive surgery. Surgical technique and perioperative management appear to differ in NA and EU centers. These differences in reporting heart valve procedures might have been influenced by variable interpretations of definitions and different patient expectations, although a uniform study protocol with consistent definitions was used at all sites. 相似文献
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