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91.
OBJECTIVE: To determine the late effectiveness of partial left ventriculectomy and risk factors for failure. METHODS: Between May 1996 and December 1998, partial left ventriculectomy and concomitant mitral valve surgery were performed in 62 patients (95% transplant candidates) with a mean age of 54 years (range 17-72 years). All patients were in New York Heart Association functional class III (38%) or IV (62%) because of idiopathic dilated cardiomyopathy (59 patients) or ischemic, valvular, or familial cardiomyopathy (1 patient each). Outcomes considered for multivariable analysis included implantation of left ventricular assist device, return to class IV heart failure, relisting for transplantation, and death. RESULTS: Partial left ventriculectomy reduced the left ventricular end-diastolic diameter immediately preoperatively to immediately postoperatively (from 8.4 +/- 1.1 cm to 5.92 +/- 0.8 cm; P =.01), reduced the left ventricular end-diastolic volume index (from 133 +/- 48.6 mL to 64.1 +/- 26 mL; P <.0001), and increased the left ventricular ejection fraction (from 16 +/- 7.6 to 31.5 +/- 10.9; P <.0001). Survival was 80% and 60% at 1 and 3 years after surgery and freedom from failure was 49% and 26%, respectively. Increased systolic pulmonary artery pressure, decreased maximum exercise oxygen consumption, and increased left atrial pressure were associated with failure and/or death. The degree of preoperative mitral regurgitation did not correlate with clinical outcome. CONCLUSIONS: Early and late failures preclude the widespread use of partial left ventriculectomy. However, in view of its sometimes beneficial effect, use in situations that do not allow for transplantation or as a biologic bridge to transplantation may be appropriate.  相似文献   
92.
OBJECTIVE: This study audited operative risk in patients undergoing urgent carotid surgery for crescendo transient ischemic attacks (TIAs). METHODS: Interrogation of the vascular unit database (January 1992 to July 2004) identified 42 patients operated on urgently for crescendo TIAs, which were defined as>or=3 TIAs within the preceding 7 days. Stroke, death, and any major cardiac events were analyzed. RESULTS: Thirty-nine patients underwent conventional endarterectomy, and three underwent interposition vein bypass. Crescendo TIA patients had sustained a median of five TIAs (range, 3 to 20) in the 7 days before surgery. Three patients died or had a stroke after surgery, for a combined stroke/death rate of 7%. This compares with 2.4% in 1000 patients undergoing elective carotid endarterectomy in this unit during the same time period. The combined stroke/death/major cardiac event rate was 14% (n=6). CONCLUSIONS: The combined risk of neurologic and cardiac complications after urgent carotid surgery for crescendo TIA is higher than that expected after elective cases but is still acceptable considering the natural history of patients with unstable neurologic symptoms.  相似文献   
93.
OBJECTIVES: Hemophilia is a sex-linked condition affecting about 1 of every 5000 males in the United States. The management of children with hemophilia can be improved with regular intravenous infusion of factor VIII or IX, thus preventing crippling and sometimes fatal hemorrhage. Maintaining this vital intravenous access is often hampered by gradual loss of superficial veins or repeated central catheter sepsis and thrombosis. This study reviewed an experience with arteriovenous fistula in selected hemophilia patients with limited venous access. METHODS: Consecutive patients operated on between October 2000 and July 2006 for venous access with the creation of an arteriovenous fistula were reviewed. They were selected because of repeated problems with other venous access. Patency, ease of use, duplex scan derived brachial artery diameter, and arm length were assessed. RESULTS: During a 69-month period, 10 arteriovenous fistulas (five brachial artery-basilic vein fistulas, 5 brachial artery-cephalic vein fistulas) were created for nine patients. The patients were a median age of 5.5 years (range, 1 to 27 years), and all were <13 except the 27-year-old patient. There were no postoperative hematomas requiring evacuation. One arteriovenous fistula failed to mature and was redone in the opposite arm, which subsequently occluded after 13 months. Of the mature fistulas, patency was 100% at 1 year, 80% (4/5) at 3 years, and 75% (3/4) at 4 years, with mean follow-up of 22 months. Brachial artery diameter increased in the involved arm by a ratio of 1.95 (range, 1.51 to 2.5) compared with the opposite arm. Arm length disparity was increased by 0.5 cm (range, 0.8 to 1.5 cm) in the involved arm. All fistulas allowed good access at home by a care provider. CONCLUSIONS: For hemophilia patients with compromised venous access, arteriovenous fistulas provide good early patency. Brachial artery diameter and arm length require continued follow-up.  相似文献   
94.

Background

We have recently shown that human epididymis protein 4 (HE4) levels correlate with the severity of cystic fibrosis (CF) lung disease. However, there are no data on how HE4 levels alter in patients receiving CFTR modulating therapy.

Methods

In this retrospective clinical study, 3 independent CF patient cohorts (US-American: 29, Australian: 12 and Irish: 19 cases) were enrolled carrying at least one Class III CFTR CF-causing mutation (p.Gly551Asp) and being treated with CFTR potentiator ivacaftor. Plasma HE4 was measured by immunoassay before treatment (baseline) and 1–6?months after commencement of ivacaftor, and were correlated with FEV1 (% predicted), sweat chloride, C-reactive protein (CRP) and body mass index (BMI).

Results

After 1?month of therapy, HE4 levels were significantly lower than at baseline and remained decreased up to 6?months. A significant inverse correlation between absolute and delta values of HE4 and FEV1 (r?=??0.5376; P?<?.001 and r?=??0.3285; P?<?.001), was retrospectively observed in pooled groups, including an independent association of HE4 with FEV1 by multiple regression analysis (β?=??0.57, P?=?.019). Substantial area under the receiver operating characteristic curve (ROC-AUC) value was determined for HE4 when 7% mean change of FEV1 (0.722 [95% CI 0.581–0.863]; P?=?.029) were used as classifier, especially in the first 2?months of treatment (0.806 [95% CI 0.665–0.947]; P?<?.001).

Conclusions

This study shows that plasma HE4 levels inversely correlate with lung function improvement in CF patients receiving ivacaftor. Overall, this potential biomarker may be of value for routine clinical and laboratory follow-up of CFTR modulating therapy.  相似文献   
95.
We treated 50 patients with fractures of the waist of the scaphoid in a below-elbow plaster cast for up to 13 weeks. Displacement of the fragments was assessed independently by two observers using MRI and radiographs performed within two weeks of injury. The MRI assessments showed that only the measurement of sagittal translation of the fragments and an overall assessment of displacement had satisfactory inter- and intra-observer reproducibility and revealed that nine of the 50 fractures were displaced. Only three of the 49 fractures with adequate follow-up failed to unite, and all were displaced with more than 1 mm of translation in the sagittal plane. If the MRI assessment of displacement of the fracture was used as the measurement of choice, assessment of displacement on the initial scaphoid series of radiographs showed a sensitivity of between 33% and 47% and a positive predictive value of between 27% and 86%. Neither observer was able correctly to identify more than 33% to 47% of the displaced fractures from the plain radiographs. Although the overall assessment of displacement and gapping and translation in the coronal plane on the plain radiographs influenced the rate of union, none of these parameters identified all three fractures which failed to unite. We conclude that the assessment of displacement of scaphoid fractures on MRI can probably be used to assess the likelihood of union although the small number of nonunions limits the power of the study. In contrast, the assessment of displacement on routine radiography is inaccurate and of less value in predicting union.  相似文献   
96.
OBJECTIVES: Activation of the neuroendocrine axis in congestive heart failure is of prognostic significance, and neurohumoral blocking therapy prolongs survival. The hypothesis that surgical reduction of left ventricular size and function decreases neuroendocrine activation is less established. We evaluated the neurohormonal response to left ventricular reconstruction surgery in ischemic cardiomyopathy. METHODS: Norepinephrine, plasma renin activity, and angiotensin II were measured in 10 patients before and 12 months after left ventricular reconstruction. In an additional 5 patients, brain natriuretric peptide was measured before and 3 months postoperatively. Three-dimensional cardiovascular imaging was used to assess ejection fraction and left ventricular end-diastolic volume index. RESULTS: Concurrent with improvements of New York Heart Association functional class (2.9 +/- 0.5 preoperatively vs 2.0 +/- 0.4 postoperatively, P <.001), ejection fraction (23.9% +/- 6.6% vs 36.2% +/- 6.2%, P <.01), and left ventricular end-diastolic volume index (140.8 +/- 33.8 mL/m(2) vs 90.6 +/- 18.3 mL/m(2), P <.01), considerable reductions were observed for median plasma profiles of norepinephrine (562.0 pg/mL vs 319.0 pg/mL, P <.05), plasma renin activity (5.75 microg/L/h vs 3.45 microg/L/h, P <.05), angiotensin II (41.0 ng/mL vs 23.0 ng/mL, P =.051), and brain natriuretric peptide (771.0 pg/mL vs 266.0 pg/mL, P <.05). The more plasma renin activity or angiotensin II decreased after left ventricular reconstruction, the higher was the increase in ejection fraction (R = -.745, P <.05 [plasma renin activity]; R = -.808, P <.05 [angiotensin II]). CONCLUSIONS: Surgical improvements of ejection fraction and left ventricular end-diastolic volume index by left ventricular reconstruction were accompanied by improvement of both the neuroendocrine activity and the functional status in patients with congestive heart failure. Whether this favorable neurohormonal response is predictive of an improved survival requires further evaluation.  相似文献   
97.
Background: Postdural puncture headache (PDPH) occurs in up to 80% of parturients who experience inadvertent dural puncture during epidural catheter placement. The authors performed a randomized double blind study to assess the effect of prophylactic epidural blood patch on the incidence of PDPH and the need for therapeutic epidural blood patch.

Methods: Sixty-four parturients who incurred inadvertent dural puncture were randomized to receive a prophylactic epidural blood patch with 20 ml autologous blood (prophylactic epidural blood patch group) or a sham patch (sham group). Subjects were evaluated daily for development of PDPH for a minimum of 5 days after dural puncture. Those who developed a PDPH were followed daily for a minimum of 3 days after resolution of the headache. Subjects with moderate headaches who reported difficulties performing childcare activities and all those with severe headaches were advised to receive a therapeutic epidural blood patch.

Results: Eighteen of 32 subjects in each group (56%) developed PDPH. Therapeutic blood patch was recommended in similar numbers of patients in each group. The groups had similar onset time of PDPH, median peak pain scores, and number of days spent unable to perform childcare activities as a result of postural headache. The median duration of PDPH, however, was shorter in the prophylactic epidural blood patch group.  相似文献   

98.
Imaging findings in hippocampal sclerosis: correlation with pathology   总被引:15,自引:0,他引:15  
We evaluated the ability of preoperative radiologic imaging to detect hippocampal sclerosis in 31 patients who underwent surgery for intractable epilepsy. Hippocampal sclerosis is commonly associated with surgically treatable temporal lobe epilepsy. It is pathologically described as neuronal cell loss with associated gliosis in the hippocampus. While previous reports have correlated imaging results with clinical or qualitative histologic findings, this study used quantitative pathologic criteria (neuronal cell density) to diagnosis hippocampal sclerosis. We focused our study on the 11 patients with cryptogenic temporal lobe epilepsy. Of these, nine had hippocampal sclerosis by pathologic criteria. MR findings included unilateral hippocampal atrophy, an increased signal in the hippocampus on long TR scans, and atrophy in the adjacent white matter and temporal lobe. Hippocampal atrophy was most frequently seen in the red nucleus plane on coronal scans, corresponding to the body of the hippocampus. We also compared hippocampal size on MR with neuronal density in surgical specimens of the 11 patients with cryptogenic temporal lobe epilepsy. A statistically significant correlation was found between MR size and neuronal density in CA3 and CA4 of the cornu ammonis and the granular cell layer of the hippocampus. Since temporal lobectomy eliminated seizures in seven of nine patients with hippocampal sclerosis, preoperative diagnosis by MR has important therapeutic consequences.  相似文献   
99.
PURPOSE: To determine the number of patients who received a diagnosis of breast cancer after having an area of clinical concern at presentation and combined negative mammographic and ultrasonographic (US) findings. MATERIALS AND METHODS: During a 4-year period, 829 patients with a palpable abnormality at presentation and combined negative mammographic and US findings were identified. The number of women who went on to receive a diagnosis of breast cancer was determined retrospectively. The authors searched the breast imaging database and the pathology database, sent a contact letter to the referring physicians, and linked their data to the State Cancer Registry. They also analyzed the breast parenchymal density among all patients who had more than 2 years of follow-up. RESULTS: Of the 829 women, 374 had follow-up information. Two-hundred thirty-three patients had negative imaging findings with more than 2 years of follow-up. The other 141 women were presumed to be cancer free, as they were not identified by the State Cancer Registry. Six (2.6%) of the 233 women had a diagnosis of breast cancer in the area of the palpable abnormality. The six cancers were diagnosed among the 156 women who had radiographically dense breast tissue (Breast Imaging Reporting and Data System category 3 or 4). Among the 77 women with predominantly fatty tissues, no cancers were diagnosed. CONCLUSION: A negative mammographic and US finding of a palpable abnormality does not exclude breast cancer, but the likelihood of breast cancer is low, approximately 2.6%-2.7%. It may be higher if the breast tissues are dense and lower if they are predominantly fatty.  相似文献   
100.
Arthroscopic intervention in early hip disease   总被引:11,自引:0,他引:11  
Advancement in diagnostic and therapeutic applications for hip arthroscopy have dispelled previous myths about early hip disease. Arthroscopic findings have established the following facts: Acetabular labral tears do occur; acetabular chondral lesions do exist; tears are most frequently anterior and often associated with sudden twisting or pivoting motions; and labral tears often occur in association with articular cartilage lesions of the adjacent acetabulum or femoral head, and if present for years, contribute to the progression of delamination process of the chondral cartilage. Magnetic resonance arthrography represents an improvement over conventional magnetic resonance imaging, it does have limitations when compared with direct observation. Although indications for hip arthroscopy are constantly expanding, the most common indications include: labral tears, loose bodies, chondral flap lesions of the acetabular or femoral head, synovial chondromatosis, foreign body removal, and crystalline hip arthropathy (gout, pseudogout, and others). Contraindications include conditions that limit the potential for hip distraction such as joint ankylosis, dense heterotopic bone formation, considerable protrusio, or morbid obesity. Complication rates have been reported between 0.5 and 5%, most often related to distraction and include sciatic or femoral nerve palsy, avascular necrosis, and compartment syndrome. Transient peroneal or pudendal nerve effects and chondral scuffing have been associated with difficult or prolonged distraction. Meticulous consideration to patient positioning, distraction time and portal placement are essential. Judicious patient selection and diagnostic expertise are critical to successful outcomes. Candidates for hip arthroscopy should include only those patients with mechanical symptoms (catching, locking, or buckling) that have failed to respond to conservative therapy. The extent of articular cartilage involvement has the most direct relationship to surgical outcomes. Improvements in technique and instrumentation have made hip arthroscopy an efficacious way to diagnose and treat a variety of intra-articular problems.  相似文献   
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