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21.
All patients undergoing heart surgery experience a certain amount of nonspecific myocardial injury documented by the release of cardiac biomarkers and associated with poor outcome. We investigated the role of unipolar radiofrequency ablation of atrial fibrillation on the release of cardiac biomarkers in 71 patients undergoing mitral valve surgery and concomitant left atrial ablation case-matched with 71 patients undergoing isolated mitral surgery. The study was powered to detect a 3 ng/mL difference. There was no difference between the 2 groups in terms of cardiac troponin I (10 +/- 5.3 versus 12 + 10.4 ng/mL; P = 0.7) or creatine kinase-MB (50 +/- 21.8 versus 57 +/- 62.0 ng/mL; P = 0.5) release. Postoperative peak cardiac troponin I levels had univariate associations with the duration of cardiopulmonary bypass (P = 0.002) and aortic cross-clamping (P = 0.001) and with the surgical technique (15 +/- 12 ng/mL for mitral valve replacement versus 9 +/- 4.8 for mitral valve repair; P = 0.0007) at univariate analysis. Mitral valve replacement was the only independent predictor of postoperative peak release of cardiac troponin I identified with multivariate analysis (P = 0.005). Radiofrequency ablation of atrial fibrillation does not significantly increase cardiac biomarker release compared with isolated mitral surgery; mitral valve repair is associated with less release of cardiac biomarkers compared with mitral valve replacement.  相似文献   
22.
Endoscopic endonasal approach to the pterygopalatine fossa: anatomic study   总被引:21,自引:0,他引:21  
Alfieri A  Jho HD  Schettino R  Tschabitscher M 《Neurosurgery》2003,52(2):374-78; discussion 378-80
OBJECTIVE: The pterygopalatine fossa is a relatively small anatomic region. Because of its rich vasculonervous contents and its connections with several intracranial and extracranial compartments, it is of particular surgical interest. Because of its deep localization and despite its small size, however, it can require extensive anatomic approaches, especially for invasive cranial base lesions. We performed a cadaveric study through a minimally invasive endoscopic endonasal approach to the pterygopalatine fossa. METHODS: We studied 16 pterygopalatine fossae in eight adult cadaveric heads in which the arteries and veins were injected with latex. For visualization, we used rod-lens endoscopes, 4 mm in diameter and 18 cm in length, with 0-, 30-, 45-, and 70-degree lenses. An endonasal middle meatal transpalatine approach, an endonasal middle meatal transantral approach, and an endonasal inferior turbinectomy transantral approach were used. RESULTS: The middle meatal transpalatine approach allows for medial exposure of the pterygopalatine fossa contents, the middle meatal transantral approach allows a lateral view, and the inferior turbinectomy transantral approach allows the widest view and room for surgical maneuvering in the medial and lateral compartments of the pterygopalatine fossa and the infratemporal fossa. CONCLUSION: Our anatomic study shows that this approach can be considered a valid minimally invasive option to approach pterygopalatine fossa lesions.  相似文献   
23.
Intraductal papillary mucinous neoplasms (IPMNs) are rare tumours rising from the pancreatic duct epithelium. They are characterized by intraductal papillary growth and thick mucin secretion; mucin fills the Wirsung and/or branch pancreatic ducts and may cause ductal dilatation. IPMNs are classified into three types, according to the site of involvement: main duct type, branch duct type, and combined type. Most branch type IPMNs are benign, while the other two types are frequently malignant. Recent advances in diagnostic imaging have led to an increased frequency of diagnosis of IPMNs, but the clinical features of them can range broadly from benign, borderline, and malignant non-invasive to invasive lesions, and their management has not yet been clearly defined. The most of patients are asymptomatic. The possibility of malignancy is increased in cases which large mural nodules are presented. Presence of a large branch type IPMN and marked dilatation of the main duct indicate the existence of adenoma. Not infrequently, synchronous or metachronous malignancies may be developed in various organs. Endoscopic retrograde cholangiopancreatography (ERCP), endoscopic ultrasonography (EUS), intraductal ultrasonography, and magnetic resonance cholangiopancreatography (MRCP) are the most valuable imaging techniques for diagnosis of these lesions. Prognosis is excellent after complete resection of benign and non-invasive malignant IPMNs. Total pancreatectomy should be reserved for patients with resectable but extensive IPMN involving the whole pancreas; its benefits must be balanced against perioperative risks.  相似文献   
24.
An endoscopic endonasal approach was performed to remove an intra-suprasellar Rathke's cleft cyst. Rathke's cleft cyst are benign lesions, rarely diagnosed because they are often asymptomatic. To the best of our knowledge, at least 475 cases of Rathke's cleft cysts have been reported. They seem to arise from remnants of Rathke's pouch, an invagination of the stomodeum. A 52-year-old woman, complaining of bilateral frontal headaches, was operated on by using an endoscopic endonasal approach, for an intra-suprasellar tumor. The pre-operative diagnosis was non-functioning pituitary adenoma. Intra-operatively a creamy-coloured viscous tissue was found. After the removal of the cyst contents and of the capsule, the suprasellar structures were seen well. The chiasmatic cistern, the chiasm, the pituitary stalk and the pituitary gland were visualized with 0 and 30 degree endoscopes. The pathological findings showed a well-differentiated cuboidal epithelium. The diagnosis was Rathke's cleft cyst. No post-operative complications were observed. The endoscopic technique was particularly suitable in this case, both for the Rathke's cleft features and for an excellent outcome. The Rathke's cleft cyst was easily removed by suction and the cyst wall was entirely removed with curettes and pituitary punches. The hypophysis was distinguished from the cyst and was preserved. The surgical manoeuvres were all done under direct visual control. The absence of nasal packing and of breathing difficulties made comfortable the post-operative outcome. Thus, the endoscopic endonasal approach can be considered the favourite technique in case of either intra- and/or suprasellar Rathke's cleft cysts.  相似文献   
25.
Background : The authors studied the changes in selected hemostatic variables in patients undergoing coronary surgery with on-pump coronary artery bypass grafting (CABG) or off-pump coronary artery bypass surgery (OPCAB) techniques.

Methods : Platelet counts and plasma concentrations of antithrombin, fibrinogen, D dimer, [alpha]2 antiplasmin, and plasminogen were measured preoperatively, 5 min after administration of heparin, 10 min after arrival in the intensive care unit, and 24 h after surgery in patients scheduled to undergo OPCAB (n = 15) or CABG (n = 15). To correct for dilution, hemostatic variables and platelet counts were adjusted for the changes in immunoglobulin G plasma concentrations and hematocrit, respectively.

Results : Adjusting for dilution, antithrombin and fibrinogen concentrations decreased to a similar extent in patients undergoing OPCAB or CABG (pooled means and 95% confidence limits of the mean: 95.5% of baseline, 93-98%, P = 0.002, and 91.7% of baseline, 88-95%, P = 0.0001), respectively, whereas [alpha]2-antiplasmin concentrations were unchanged. Only CABG was associated with a reduction in platelet counts (76% of baseline, 66-85%, P = 0.0001), plasminogen concentrations (96% of baseline, 91-99%, P = 0.011), and increased D-dimer formation (476%, 309-741%, P = 0.004). Twenty-four hours after surgery, platelet counts were still lower in patients undergoing CABG (P = 0.049), but all the investigated variables adjusted for dilution were similar in the two groups.  相似文献   

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Twenty-two patients (19 men) with heart failure (16 ischemic, 6 dilated cardiomyopathy; mean age of 67 +/- 6 years) in New York Heart Association classes I (2 patients), II (18 patients), and III (2 patients) under optimal therapy were strictly monitored after carvedilol supplementation. The Tei index decreased significantly from 0.87 +/- 0.17 to 0.53 +/- 0.29 (p <0.03). Conversely, the ejection fraction and transmitral Doppler flow analysis did not show significant improvement, despite a trend toward the amelioration of the ejection fraction, the E-/A-wave ratio, and atrial contribution. The Tei index could represent an earlier marker to evaluate drug-induced left ventricular function improvement in patients with heart failure and could represent a more sensitive tool to monitor left ventricular function during drug interventions.  相似文献   
29.
The authors performed the experimental model of infarct-like myocardial lesions in rats treated with large doses of ISP. Myocardial necrosis was assessed on the basis of serum enzyme changes as well as of gross and microscopic findings. The infarct size was measured by a direct enzymatic method assaying creatine kinase (CK) depletion in infarcted myocardium. Pretreatment of the infarcted rats with antiplatelet (Lysin Acetyl Salicylate) or calcium antagonist drugs (Verapamil or Nifedipine) allowed the reduction of the necrotic area. Since a smaller size of infarct was achieved through different types of interventions it should be suggested that ISP-myocardial damage is due to several effects of the drug involving metabolic, vascular and/or coagulative patterns.  相似文献   
30.
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