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1.
The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.  相似文献   
2.
Radiation therapy in the management of desmoid tumors   总被引:4,自引:0,他引:4  
Purpose: To evaluate the outcome of patients with extra-mesenteric desmoid tumors treated with radiation therapy, with or without surgery.

Methods and Materials: The outcome for 75 patients receiving radiation for desmoid tumor with or without complete gross resection between 1965 and 1994 was retrospectively reviewed utilizing univariate and multivariate statistical methods.

Results: With a median follow-up of 7.5 years, the overall freedom from relapse was 78% and 75% at 5 and 10 years, respectively. Of the total, 23 patients received radiation for gross disease because it was not resectable. Of these 23 patients, 7 sustained local recurrence, yielding a 31% actuarial relapse rate at 5 years. Radiation dose was the only significant determinant of disease control in this group. A dose of 50 Gy was associated with a 60% relapse rate, whereas higher doses yielded a 23% relapse rate (p < 0.05). The other 52 patients received radiation in conjunction with gross total resection of tumor. The 5- and 10-year relapse rates were 18% and 23%, respectively. No factor correlated significantly with disease outcome. There was no evidence that radiation doses exceeding 50 Gy improved outcome. Positive resection margins were not significantly deleterious in this group of irradiated patients. For all 75 patients, there was no evidence that radiation margins exceeding 5 cm beyond the tumor or surgical field improved local-regional control. Ultimately, 72 of the 75 patients were rendered disease-free, but 3 required extensive surgery (amputation, hemipelvectomy) to achieve this status. Significant radiation complications were seen in 13 patients. Radiation dose correlated with the incidence of complications. Doses of 56 Gy or less produced a 5% 15-year complication rate, compared to a 30% incidence with higher doses (p < 0.05).

Conclusions: Radiation is an effective modality for desmoid tumors, either alone or as an adjuvant to resection. For patients with negative resection margins, postoperative radiation is not recommended. Patients with positive margins should almost always receive 50 Gy of postoperative radiation. Unresectable tumors should be irradiated to a dose of approximately 56 Gy, with a 75% expectation of local control.  相似文献   

3.
BackgroundTo explore the prognostic value of left ventricular (LV) longitudinal systolic dysfunction in patients with hypertension.MethodsIn 156 hypertensive subjects, LV longitudinal systolic function was assessed by echocardiographic measurement of M-mode left atrioventricular plane displacement (AVPD) and Tissue Doppler (TD)-derived mitral annulus peak systolic velocity (S(m)). Patients were followed for development of the following cardiovascular events: congestive heart failure requiring hospitalization, new-onset angina, nonfatal myocardial infarction, coronary revascularization procedures, transient ischemic attack, nonfatal stroke, and cardiovascular death.ResultsOver a follow-up of 23.3 +/- 5.4 months, 24 patients had 29 events. Both longitudinal systolic indices were predictive of outcome (hazard ratios: AVPD, 0.24, P < 0.001; S(m), 0.22; P < 0.001). AVPD 相似文献   
4.
Compression of the heart outside the pericardial sac is a rare cause of hemodynamic compromise and cardiac tamponade. We report an atypical case of regional cardiac compression caused by a large loculated anaerobic bacterial empyema.  相似文献   
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There is still some debate regarding the prognostic significance of left ventricular longitudinal systolic dysfunction as assessed by tissue Doppler (TD) imaging in patients with chronic heart failure (HF), since previous studies have included patients with postischemic wall motion abnormalities. Thus, this study was designed to ascertain whether TD-derived longitudinal systolic dysfunction may influence the outcome of patients with nonischemic chronic HF. In 200 consecutive patients with chronic HF secondary to dilated cardiomyopathy and no history of ischemic heart disease, peak systolic mitral annular velocity (S(m) ) was measured by pulsed TD at the septal and lateral annular sites. The end points were cardiac death or hospitalization for worsening HF. Mean follow-up duration was 30 months. In a time independent analysis, averaged S(m) calculated as the average of septal and lateral S(m) , resulted to be a significant predictor of outcome in the study population (area under receiver-operator characteristic curve: cardiovascular death, 0.69, P < 0.0001; cardiovascular events, 0.64, P = 0.0005). In a time-dependent analysis, average S(m) was associated with both cardiovascular death (hazard ratio 0.832, P = 0.0019) and cardiovascular events (hazard ratio 0.904, P = 0.039), independently of other clinical risk factors and echocardiographic parameters of systolic function. Septal S(m) but not lateral S(m) was independently associated with the outcome measures. In conclusion, the assessment of systolic mitral annular velocity by pulsed TD is a useful indicator for prognostic stratification of patients with nonischemic dilated cardiomyopathy and chronic HF.  相似文献   
7.
The impact of left ventricular (LV) diastolic dysfunction on risk of atrial fibrillation (AF) recurrence is still unknown. The aim of this study was to assess the role of LV diastolic dysfunction in predicting AF recurrence after successful electrical cardioversion in patients with nonvalvular AF. In 51 patients with a first episode of nonvalvular AF undergoing successful electrical cardioversion, tissue Doppler echocardiography was performed to measure peak early diastolic mitral annulus velocity (E(m)) and the ratio of mitral inflow to mitral annulus velocity at end-diastole (E/E(m)). Clinical end points were recurrent persistent AF at 2-week follow-up (early AF recurrence [ERAF]) and at 1-year follow-up (including ERAF and late AF recurrence). Seventeen patients showed evidence of ERAF, whereas late AF recurrence occurred in another 5 patients. In time-independent analysis E/E(m) (odds ratio [OR] 1.746, p = 0.0084) and indexed LV end-systolic volume (OR 1.083, p = 0.040) were independent predictors of ERAF. Based on a logistic model risk of ERAF was 25% for an E/E(m) of 5.6 but increased to 50% for an E/E(m) of 8.1 and to 75% for an E/E(m) of 10.5. In time-dependent analysis E/E(m) emerged as the only predictor of ERAF (OR 1.757, p = 0.0078). E/E(m) also independently predicted risk of recurrence at 1 year in time-independent (OR 1.757, p = 0.0078) and time-dependent (OR 1.319, p = 0.0003) analyses. In conclusion LV diastolic dysfunction independently predicts AF recurrence in patients with nonvalvular AF undergoing successful electrical cardioversion.  相似文献   
8.
Spermatic cord sarcoma: outcome, patterns of failure and management   总被引:2,自引:0,他引:2  
PURPOSE: We evaluate the outcome, clarify the patterns of failure and suggest treatment strategies for sarcoma in the spermatic cord. MATERIALS AND METHODS: Between 1956 and 1998, 32 patients with spermatic cord sarcoma were treated at M. D. Anderson Cancer Center. A retrospective review of disease outcome, patterns of relapse and patient survival was performed. RESULTS: Histological subtypes of sarcoma were malignant fibrous histiocytoma in 12 patients, leiomyosarcoma in 6, liposarcoma in 8 and other subtypes in 6. All except 2 patients underwent radical orchiectomy with or without additional resection to achieve negative margins. Margins were microscopically negative in 29 cases and positive in 3. There were 3 patients who received adjuvant radiation to the surgical site. With a median followup of 9 years the 10 and 15-year actuarial local control, distant metastasis-free and overall survival rates were 72% and 61%, 85% and 85%, and 63% and 52%, respectively. The major pattern of failure was local recurrence that occurred in 8 of the 12 patients in whom disease relapsed and was the sole site of relapse in 7. Pelvic nodes had relapsed in 2 patients and para-aortic nodes in 1. Hematogenous metastases had developed in 4 patients. Of the 7 cases of disease that recurred locally only 3 were salvaged. No relapse occurred in the 3 patients treated with combined surgery and radiation. CONCLUSIONS: Spermatic cord sarcoma has a high propensity for local recurrence after surgery. Nodal relapse is less frequent than commonly believed. Because of the relatively high local failure rate seen in surgery alone and durable local control noted in 3 patients treated with surgery plus radiotherapy, combined modality treatment should be considered in those with spermatic cord sarcoma who are believed to be at high risk for local failure.  相似文献   
9.
OBJECTIVE: To use an established dysphagia clinical screening system to evaluate outcomes in acute stroke patients. DESIGN: Case-control study. SETTING: Tertiary care center. PARTICIPANTS: Acute stroke patients (n = 56) consecutively referred to a speech pathology service. MAIN OUTCOME MEASURES: Outcomes (ie, pneumonia, dietary status at discharge) in patients who were referred for a videofluoroscopic swallow study (VSS) based on results of a previously validated clinical screening system were compared with outcomes in patients who were not referred for VSS based on the clinical evaluation. RESULTS: Thirty-eight of 56 patients (68%) presented with 2 or more clinical predictors of moderate to severe dysphagia and were further evaluated with VSS, whereas 18 patients (32%) had fewer than 2 clinical features and were not evaluated radiographically. Based on patient outcomes and VSS results, identification of at least 2 clinical predictors significantly distinguished patients with moderate to severe dysphagia from patients with mild dysphagia or normal swallowing. None of the patients in either group developed pneumonia while following recommendations of the clinical or dynamic swallowing evaluation, and 93% of the patients returned to a regular diet. CONCLUSIONS: These data demonstrate that clinical use of this screening system can objectively identify acute stroke patients who warrant further diagnostic studies and can safely determine which patients need no further deglutitive evaluation.  相似文献   
10.
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