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51.
The sliding leaflet technique reduces the incidence of left ventricular outflow tract obstruction after mitral valve repair. We report a modification of this technique that simplifies the procedure. 相似文献
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Katzan IL Masaryk TJ Furlan AJ Sila CA Perl J Andrefsky JC Cosgrove DM Sabik JF McCarthy PM 《Neurology》1999,52(5):1081-1084
Recent major surgery is an exclusion criterion for thrombolysis. Six patients with acute ischemic stroke underwent intra-arterial thrombolysis after recent open heart surgery without clinically significant bleeding complications, although one patient developed a small, asymptomatic cerebellar hemorrhage. Intra-arterial thrombolysis may be an option for patients with cerebral embolism in the perioperative period. 相似文献
55.
Stephen E. Jones Yuji Kasamaki Toshitsugu Ogura Lesya M. Shuba John R. McCullough Terence F. McDonald 《European journal of pharmacology》1999,370(3):863-327
The antispasmodic agent terodiline has cardiotoxic effects that include QT lengthening. To determine whether inhibition of inwardly-rectifying K+ current (IK1) might be a factor in the cardiotoxicity, we measured IK1 in guinea pig ventricular myocytes. Terodiline reduced outward IK1 with an IC50 of 7 μM; maximal reduction was 60% with 100–300 μM concentration. Inhibition was independent of current direction, and persisted after removal of the drug. Terodiline (3–5 μM) lengthened action potentials in guinea pig papillary muscles by ca. 10%, primarily by slowing phase 3 repolarization; higher concentrations abbreviated the plateau and markedly slowed late repolarization. Terodiline washout provoked an extra lengthening, consistent with persistent inhibition of IK1 and rapid recovery of net inward plateau current. The results suggest that inhibition of IK1 is a likely factor in the cardiotoxicity of the drug. 相似文献
56.
Renal cell carcinoma with inferior vena cava tumor thrombi 总被引:5,自引:0,他引:5
J E Montie R el Ammar J E Pontes S V Medendorp A C Novick S B Streem R Kay D K Montague D M Cosgrove 《Surgery, gynecology & obstetrics》1991,173(2):107-115
Renal cell carcinoma is a unique neoplasm because of its common propensity to propagate into the renal vein and inferior vena cava (IVC) as tumor thrombus. Historically, the surgical difficulties encountered in removal of these cancers limited the ability of a single institution to obtain experience with large numbers of instances. Between January 1956 and July 1987, 68 patients with renal cell carcinoma extending into the IVC or right atrium underwent radical nephrectomy with vena cava thrombus extraction at the Cleveland Clinic. Twenty-five patients had partial resection of the IVC with reconstruction. Fifteen patients had partial resection and reconstruction of the IVC; however, because of narrowing of the infrarenal IVC, persisting bland thrombus in the proximal IVC or iliac veins or concern regarding postoperative pulmonary emboli, the infrarenal IVC was either ligated or clipped. Seven patients underwent cavectomy with division of the IVC. A right atriotomy was performed upon 14 patients and cardiopulmonary bypass was used in 20 patients, with 17 also having deep hypothermic circulatory arrest. The tumor thrombus was removed intact in 64 per cent of the patients and in multiple small fragments ("piecemeal") in 36 per cent of the patients. The mortality rate was 7 per cent. Survival was examined relative to extent of vena caval thrombus. Patients with extension into the atrium had a significantly worse prognosis than those with other levels of vena caval involvement. Other factors, such as lymph node status, perinephric fat involvement, resection of IVC and intact or "piecemeal" extraction, did not influence the survival rate. Patients with pre-existing metastases preoperatively had an extremely poor survival rate. The techniques now available for surgical resection of all levels of tumor thrombus of the IVC make resection feasible in most patients. In our opinion, the addition of deep hypothermic circulatory arrest has been a significant advance. 相似文献
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J E Montie J E Pontes A C Novick S Vanderburg Mendendorp S B Streem D K Montague D Cosgrove 《The American surgeon》1991,57(1):56-61
Renal cell carcinoma is an unusual cancer with the propensity to invade not only the renal vein but to propagate into the inferior vena cava (IVC) as a tumor thrombus. Experience has recently confirmed that MRI will be valuable in evaluating the extent of the tumor thrombus. The surgical techniques used to remove the thrombus are dependent on the extent of the cancer. For lesions involving the infrahepatic IVC, only proximal and distal control of the IVC are necessary. For a thrombus involving the intrahepatic IVC, isolation of the suprahepatic IVC, hepatic circulation, and infrahepatic IVC or cardiopulmonary bypass can be used. For the large thrombus in the supradiaphragmatic IVC or atrium, cardiopulmonary bypass either with or without deep hypothermic circulatory arrest is appropriate. In a review of 48 cases with renal cell carcinoma with IVC tumor thrombi, the tumor thrombus was removed intact in 58 per cent and in multiple fragments ("piece-meal") in 42 per cent of the patients. Cardiac bypass has been used in 26 cases with 22 undergoing deep hypothermic circulatory arrest. The postoperative mortality of 48 cases between 1965 and 1987 was 4 per cent. Removal of the most complicated and extensive renal cell carcinoma tumor thrombi is now technically feasible. In patients with large tumor thrombi, however, the ultimate outlook remains poor in the absence of effective systemic adjuvant therapy. 相似文献
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Eskandar EN Shinobu LA Penney JB Cosgrove GR Counihan TJ 《Journal of neurosurgery》2000,92(3):375-383
OBJECT: Pallidotomy for the treatment of medically refractory Parkinson's disease (PD) has enjoyed renewed popularity. However, the optimal surgical technique, lesion location, and long-term effectiveness of pallidotomy remain subjects of debate. In this article the authors describe their surgical technique for performing pallidotomy without using microelectrode guidance, and the clinical and radiological results of this procedure. METHODS: Patients were evaluated preoperatively by using a battery of validated clinical rating scales and magnetic resonance (MR) imaging of the brain. Individuals with severe treatment-refractory idiopathic PD who were believed to be good candidates for surgery underwent computerized tomography scanning- and MR imaging-guided stereotactic pallidotomy. Intraoperative macrostimulation was used to optimize lesion placement and to avoid injury to nearby structures. Lesion location and size were calculated from MR imaging sequences of the brain obtained within the first 24 hours after surgery and again 3 months later. Clinical examinations were conducted at 1.5, 3, 6, 12, and 24 months after surgery. Seventy-five patients (mean age 61 years, range 38-79 years) underwent unilateral pallidotomy. Significant improvements were observed in the "off' period scores for the activities of daily living portion of the Unified Parkinson's Disease Rating Scale (UPDRS), the UPDRS motor scores, total "on" time, levodopa-induced dyskinesias, and contralateral tremor. These improvements were maintained 24 months postoperatively. The mean lesion volume measured on the immediate postoperative MR image was 73 +/- 5.4 mm3. Radiological analysis suggests that initial lesion volume does not predict outcome. The only permanent major complication was a single visual field defect. CONCLUSIONS: Pallidotomy performed without using microelectrode guidance is a safe and effective treatment for selected patients with medically refractory PD. 相似文献
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