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61.
Doppler echocardiographic examinations were performed in 146 patients with normal and 42 patients with pathological (31 regurgitations and 11 obstructions) mitral valve prostheses confirmed by catheterisation and/or surgery. The maximum and mean transprosthetic gradients and pressure half times (PHT) were calculated from continuous wave Doppler recordings and regurgitant signals were searched for by continuous and pulsed wave Doppler. In the group of normal mitral valve prostheses, the mean gradients and PHT were very variable even within the subgroups of the same type and size of prosthesis. The best haemodynamic profile was observed with the St Jude prosthesis (mean gradient = 5 +/- 2 mmHg, PHT = 90 +/- 22 ms, p less than 0.05 vs other prostheses). Minimal mitral regurgitation was detected in 12 per cent of bioprostheses and 20 per cent of mechanical prostheses. No correlations were found between the mean pressure gradient or PHT and the size of the prostheses. Regular Doppler echocardiographic follow-up over 2.4 years was obtained in 25 patients and showed a remarkable stability of the Doppler parameters in 17 patients whereas prosthetic valve dysfunction was diagnosed in the other 8 cases. In the group of pathological mitral valve prostheses, regurgitation (N = 31) was associated with a high early diastolic pressure gradient (20.2 +/- 8 mmHg) and a normal or shortened PHT (84 +/- 28 ms). Obstructed prostheses (N = 11) had high mean pressure gradients (17 +/- 5 mmHg) and increased PHT (195 +/- 53 ms). All cases of obstruction were correctly identified by the Doppler but 4 prosthetic valve regurgitations were missed or underestimated (4 mechanical prostheses).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
62.
A 69-year-old woman presented with chest pain and electrocardiographic evidence of subacute anterior ischaemia. Transthoracic and transesophageal echocardiography allowed correct diagnosis of a posttraumatic pseudoaneurysm of the left sinus of Valsalva. The large pseudoaneurysm caused compression of the left main coronary artery and was successfully treated by aortic root replacement, left main coronary artery ligation, and arterial bypass.  相似文献   
63.
Echocardiography predicts embolic events in infective endocarditis   总被引:14,自引:0,他引:14  
OBJECTIVES: The aim of our study was to assess the value of transesophageal echocardiography (TEE) in predicting embolic events (EEs) in a large group of patients with definite endocarditis according to the Duke criteria, including silent embolism. BACKGROUND: The value of echocardiography in predicting embolism in patients with endocarditis remains controversial. Some studies reported an increased risk of embolism in patients with large and mobile vegetations, whereas other studies failed to demonstrate such a relationship. METHODS: Multiplane transesophageal echocardiograms of 178 consecutive patients with definite infective endocarditis (IE) were analyzed. The incidence of embolism was compared with the echocardiographic characteristics (localization, size and mobility) of the vegetations. To detect silent embolism, cerebral and thoraco-abdominal scans were performed in 95% of patients. RESULTS: Among 178 patients, 66 (37%) had one or more EEs. There was no difference between patients with and without embolism in terms of age, gender and left valve involved. On univariate analysis, Staphylococcus infection, right-side valve endocarditis and vegetation length and mobility were significantly related to EEs. A significant higher incidence of embolism was present in patients with vegetation length >10 mm (60%, p < 0.001) and in patients with mobile vegetations (62%, p < 0.001). Embolism was particularly frequent among 30 patients with both severely mobile and large vegetations (> 15 mm) (83%, p < 0.001). On multivariate analysis, the only predictors of embolism were vegetation length (p = 0.03) and mobility (p = 0.01). CONCLUSIONS: Our study shows that the presence of vegetations on TEE is predictive of embolism and that the morphologic characteristics of vegetations are helpful in predicting EEs in both mitral and aortic valve IE. It also suggests that early operation may be recommended in patients with vegetations > 15 mm and high mobility, irrespective of the degree of valve destruction, heart failure and response to antibiotic therapy.  相似文献   
64.
The objectives were to determine the prevalence and clinical significance of anti-cyclic citrullinated peptide (anti-CCP) antibodies in patients with juvenile idiopathic arthritis (JIA). Anti-CCP antibodies were checked by ELISA in 68 children with JIA, 38 males and 30 females with mean age of 10.6 (±4.02) years and disease duration of 3.7 (±1.8) years. Thirty-eight (56%) patients had polyarticular disease, 20 (29%) patients had oligoarticular disease and 10 (15%) patients had systemic onset disease. All patients had their antinuclear antibodies (ANA), rheumatoid factor (RF) and ESR checked and x-rays performed to look for erosions. Results were compared to those of 20 healthy children, 14 children with juvenile systemic lupus erythematosus (JSLE) and 30 adults with rheumatoid arthritis (RA). Anti-CCP antibodies were positive in 14/68 (20.6%) patients with JIA, all had polyarticular-onset disease. All patients with positive anti-CCP antibodies had RF-positive polyarthritis. Anti-CCP antibodies were negative in all patients with oligoarticular-onset and systemic-onset disease including 2 patients with extended oligoarthritis. Anti-CCP antibodies were negative in healthy and JSLE controls but were positive in 20/30 (66.5%) adults with RA. Anti-CCP antibodies correlated significantly with joint erosions in patients with JIA (p?=?0.004) but no significant relation was found between anti-CCP antibodies and ANA positivity or raised ESR. These data confirm that anti-CCP antibodies are less prevalent in JIA than adult RA but are detectable in a significant proportion of RF-positive patients with polyarticular-onset JIA. The current study showed significant relation between anti-CCP positivity and erosive joint disease in JIA.  相似文献   
65.
Camelidae are known to produce immunoglobulins (Igs) devoid of light chains and constant heavy-chain domains (CH1). Antigen-specific fragments of these heavy-chain IgGs (VHH) are of great interest in biotechnology applications. This paper describes the first example of successfully raised heavy-chain antibodies in Camelus dromedarius (single-humped camel) and Camelus bactrianus (two-humped camel) against a MUC1 related peptide that is found to be an important epitope expressed in cancerous tissue. Camels were immunized against a synthetic peptide corresponding to the tandem repeat region of MUC1 mucin and cancerous tissue preparation obtained from patients suffering from breast carcinoma. Three IgG subclasses with different binding properties to protein A and G were purified by affinity chromatography. Both conventional and heavy-chain IgG antibodies were produced in response to MUC1-related peptide. The elicited antibodies could react specifically with the tandem repeat region of MUC1 mucin in an enzyme linked immunosorbant assay (ELISA). Anti-peptide antibodies were purified after passing antiserum over two affinity chromatography columns. Using ELISA, immunocytochemistry and Western blotting, the interaction of purified antibodies with different antigens was evaluated. The antibodies were observed to be selectively bound to antigens namely: MUC1 peptide (tandem repeat region), human milk fat globule membrane (HMFG), deglycosylated human milk fat globule membrane (D-HMFG), homogenized cancerous breast tissue and a native MUC1 purified from ascitic fluid. Ka values of specific polyclonal anti-peptide antibodies were estimated in C. dromedarius and C. bactrianus, as 7 × 1010 M? 1 and 1.4 × 1010 M? 1 respectively.  相似文献   
66.
In this study, the (5,10,15,20-tetrakis[(4-methoxyphenyl)]porphyrinato)cadmium(ii) complex ([Cd(TMPP)]) was successfully used as a modifier in a carbon paste electrode (CPE) and exploited for bisphenol A (BPA) detection. Analytical performance revealed two linear ranges from 0.0015–15 μM and 0.015–1.5 mM with a detection limit of 13.5 pM. The proposed method was implemented in water samples, which resulted in quantitative signals over the range 6.5–1000 μM with recoveries between 92.6 and 107.7% for tap water and between 96.6 to 106.0% for mineral water.

In this study, the (5,10,15,20-tetrakis[(4-methoxyphenyl)]porphyrinato)cadmium(ii) complex ([Cd(TMPP)]) was successfully used as a modifier in a carbon paste electrode (CPE) and exploited for bisphenol A (BPA) detection.  相似文献   
67.
BACKGROUND: Sphincter of Oddi dysfunction is diagnosed at manometry and, after cholecystectomy, non-invasively at quantitative choledochoscintigraphy. Patients may benefit from endoscopic sphincterotomy. AIMS: The aim of this study was to assess the usefulness of choledochoscintigraphy compared with manometry in predicting outcome of sphincterotomy in post cholecystectomy patients with sphincter of Oddi dysfunction. PATIENTS AND METHODS: Thirty patients with biliary-type pain complying with the Rome diagnostic criteria of sphincter of Oddi dysfunction and belonging to biliary group I and II were subjected to clinical evaluation, choledochoscintigraphic assessment of the hepatic hilum-duodenum transit time, endoscopic retrograde cholangiopancreatography, and perendoscopic manometry. Twenty two biliary group I and II patients with prolonged hepatic hilum-duodenum transit times were invited to undergo sphincterotomy. Fourteen patients underwent sphincterotomy; eight refused. Clinical and scintigraphic assessments were performed at follow up. RESULTS: Hepatic hilum-duodenum transit time was delayed in all patients with manometric evidence of sphincter of Oddi dysfunction, in all biliary group I patients and in 64% of biliary group II patients. At follow up, all patients who underwent sphincterotomy were symptom free and hepatic hilum-duodenum transit time had either normalised or significantly improved. A favourable post sphincterotomy outcome was predicted in 93% of cases at choledochoscintigraphy and in 57% at manometry. CONCLUSIONS: Quantitative choledochoscintigraphy is a useful and non-invasive test to diagnose sphincter of Oddi dysfunction as well as a reliable predictor of sphincterotomy outcome in post cholecystectomy biliary group I and II patients, irrespective of clinical classification and manometric findings.  相似文献   
68.
69.

Background

Coronary computed tomography angiography (CCTA) is increasingly being used for the evaluation of coronary artery disease; however, radiation exposure remains a major limitation of its use.

Objective

To compare image quality and radiation exposure in two groups of patients undergoing CCTA using a 256-slice dual-source helical computed tomography scanner with high-pitch (FLASH) or prospective [step-and-shoot (SAS)] gating protocols.

Methods

A prospective, single-center study was performed in our cardiac center. In total, 162 patients underwent CCTA with either FLASH or SAS scanning protocols. Subjective image quality was graded on the basis of a four-point grading system (1, non-diagnostic; 2, adequate; 3, good; 4, excellent). Objective image quality was assessed using image signal, noise, and signal-to-noise ratio (SNR). The effective radiation dose was also estimated.

Results

The clinical and demographic characteristics of the patients in both groups were similar. The median age of the patients in both groups was 48.43?years, and males accounted for 63% and 68.7% of the FLASH and SAS groups, respectively. We found that the subjective image quality obtained with the FLASH protocol was superior to that obtained with the SAS protocol (3.35?±?0.6?mSv vs. 2.82?±?0.61?mSv; p?<?0.001). Image noise was higher in the FLASH group but was not statistically significant (25.0?±?6.13 vs. 24.0?±?6.8; p?=?0.10), whereas the signal and SNR was significantly higher with the FLASH protocol than with the SAS protocol [(469?±?116 vs. 397?±?106; p?>?0.001) and (21.6?±?8.7?mSv vs. 16.6?±?7.7?mSv; p?<?0.001), respectively]. Radiation exposure was 62% lower in the FLASH protocol than in the SAS protocol, (1.9?±?0.4?mSv vs. 5.12?±?1.8?mSv; p?<?0.001).

Conclusion

The use of 256-slice CCTA performed with the FLASH protocol has a better objective and subjective image quality as well as lower radiation exposure when compared with the use of prospective electrocardiography gating.  相似文献   
70.
PURPOSE: To describe clinical features and outcomes of enterococcal left-sided native valve endocarditis and to compare it to endocarditis caused by other pathogens. SUBJECTS AND METHODS: Patients in the International Collaboration on Endocarditis-Merged Database were included if they had left-sided native valve endocarditis. Demographic characteristics, clinical features, and outcomes were analyzed. Multivariable analysis evaluated enterococcus as a predictor of mortality. RESULTS: Of 1285 patients with left-sided native valve endocarditis, 107 had enterococcal endocarditis. Enterococcal endocarditis was most frequently seen in elderly men, frequently involved the aortic valve, tended to produce heart failure rather than embolic events, and had relatively low short-term mortality. Compared to patients with non-enterococcal endocarditis, patients with enterococcal endocarditis had similar rates of nosocomial acquisition, heart failure, embolization, surgery, and mortality. Compared to patients with streptococcal endocarditis, patients with enterococcal endocarditis were more likely to be nosocomially acquired (9 of 59 [15%] vs 2 of 400 [1%]; P <.0001) and have heart failure (49 of 107 [46%] vs 234 of 666 [35%]; P = 0.03). Compared to patients with S. aureus endocarditis, patients with enterococcal endocarditis were less likely to embolize (28 of 107 [26%] vs 155 of 314 [49%]; P <.0001) and less likely to die (12 of 107 [11%] vs 83 of 313 [27%]; P = 0.001). Multivariable analysis of all patients with left-sided native valve endocarditis showed that enterococcal endocarditis was associated with lower mortality (odds ratio [OR] 0.49; 95% confidence interval [CI] 0.24 to 0.97). CONCLUSIONS: Enterococcal native valve endocarditis has a distinctive clinical picture with a good prognosis.  相似文献   
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