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Percutaneous balloon aortic valvotomy was attempted in six consecutiveadolescents and young adults, (meanage 18 ± 5 years),with severe congenital aortic valvular stenosis. Peak systolicaortic valve gradient measurement and aortography was performedbefore and immediately after valvotomy, and a 16 monthsfollow-up. The single-balloon technique was used in two patientsand the double-balloon technique in four patients. After balloonvalvotomy the mean peak systolic aortic valve gradient (PSG)decreased from 122 ± 53 to 43 ± 20 mmHg (P >001). The haemodynamic improvement persisted at follow-up (PSG= 47 ±31 mmHg), except in one patient who had previouslyundergone aortic surgical valvotomy. One balloon valvotomy wasunsuccessful, presumably because of the selection of an inappropriatelysmall balloon. Two patients with critical aortic stenosis (PSG>165mmHg), who exhibited a thick aortic valve on echocardiographywith a relatively small aortic root and annulus, had a dramaticreduction in PSG. However, the degree of aortic regurgitationincreased significantly in both cases. The theoretical haemodynamicadvantage of the double versus the single balloon techniqueswas confirmed in one patient. We have demonstrated that percutaneousballoon aortic valvotomy using either the single- or double-balloontechnique is feasible in young adults with severe congenitalaortic stenosis. Further studies are required both to defineappropriate patients and the selection of balloon diameter andlength. 相似文献
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Christoph A. Nienaber Yskert von Kodolitsch Carsten J. Brockhoff Dietmar H. Koschyk Rolf P. Spielmann 《The International Journal of Cardiac Imaging》1994,10(1):1-14
Thirty-five consecutive patients with clinically suspected aortic dissection were subjected to a dual noninvasive imaging protocol using comprehensive echocardiography and ECG-triggered MRI with multi-slice spin echo and cine sequences in random order. The purpose of this dual imaging study was to compare the diagnostic accuracy of two-dimensional and color-coded Doppler echocardiography using the conventional transthoracic (TTE) and the transesophageal approach (TEE) with magnetic resonance imaging (MRI) for the exact morphologic evaluation and anatomical mapping of the thoracic aorta. The results of each diagnostic method were validated independently against the gold standard of intraoperative findings (n=17), necropsy (n=4) or contrast angiography (n=22).Compared to conventional transthoracic echocardiography both TEE and MRI were more reliable in detecting aortic dissections (TTE vs TEE: p<0.02; TTE vs MRI: p<0.01) and associated epiphenomena. Moreover, the reliability of TTE decreased significantly from proximal to distal segments of the aorta, e.g. from the ascending segment to the arch (p<0.05) and to the descending aorta (p<0.005), whereas the sensitivities of both TEE and MRI were excellent irrespective of the site of dissection. With regard to epiphenomena such as thrombus formation and entry location, MRI emerged as the optimal method for detailed morphologic information in all segments of the aorta. No serious side effects were encountered with either method.Thus, in patients with suspected acute or subacute aortic dissections the echocardiographic assessment should include the transesophageal approach for significant improvement of the moderate sensitivity and specificity of TTE. Both TEE and MRI are non-traumatic, safe and diagnostically accurate to identify and classify acute and subacute dissections of the thoracic aorta irrespective of their location. MRI provides superb anatomical mapping of all type A and B dissections and more detailed information on the site of entry and thrombus formation than TEE. These features of TEE and MRI may render retrograde contrast angiography obsolete in the setting of thoracic aortic dissection and may encourage surgical interventions exclusively on the basis of noninvasive imaging. 相似文献
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Yousra H. AL JAZAIRY Hassan Suliman HALAWANY Nawaf AL HUSSAINAN Nassr AL MAFLEHI Nimmi Biju ABRAHAM Vimal JACOB 《Industrial health》2014,52(4):324-333
A disparity exists in the educational qualifications of dental assistants working in
various public and private institutions in Riyadh, Saudi Arabia. The aim of this study was
to assess the influence of professional and personal characteristics on job satisfaction
among dental assistants. A cross-sectional survey was performed among dental assistants
using a 24-item self-administered questionnaire. Multinomial logistic regression was used
to assess the relationship between overall job satisfaction and other variables. The
overall response rate was 72.1%. Factor analysis suggested that five underlying factors
were related to job satisfaction. The mean score for overall job satisfaction was 3.86
(satisfied) out of 5. Among the work environment factors, the highest mean score, 4.26
(satisfied), was obtained for quality of service, and the lowest mean score, 2.78
(neutral), was obtained for the perception of income. The income and general prospects of
the profession was significantly associated with overall job satisfaction. This study
suggests that for dental assistants, professional and personal life, quality of service,
perception of income and prestige and self-respect are important factors for job
satisfaction. Despite differences in professional formation standards, in general, the
study participants were considerably satisfied with their jobs. 相似文献
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Iman Amy Betawi Sinaria Kamil Abdel Jabbar Mohammad. A. AL Jabery Haidar Ibrahim Zaza Muhannad Al-Shboul 《Early child development and care》2014,184(12):1992-2003
This study examined fathers' perceptions regarding their home-based activities (HBA) and the influence of fathers' demographic characteristics on their perceptions and practices at home. A total of 396 fathers completed a survey questionnaire describing their demographic information, perceptions and their practices regarding their involvement in HBA. Results indicated that fathers have moderate level of practice concerning their HBA, yet they have low perception of their actual practice at HBA. In addition, there was a statistical significance in HBA due to fathers' age, educational level and specialisation which had an influence on their perceptions as well. Recommendations and implications of future research were discussed. 相似文献
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Danielle Carpenter Carmen Taype Jon Goulding Mike Levin Brian Eley Suzanne Anderson Marie-Anne Shaw John AL Armour 《BMC medical genetics》2014,15(1):1-8
Background
22q11.2 deletion syndrome (22q11.2DS) is a common microdeletion syndrome, which occurs in approximately 1:4000 births. Familial autosomal dominant recurrence of the syndrome is detected in about 8-28% of the cases. Aim of this study is to evaluate the intergenerational and intrafamilial phenotypic variability in a cohort of familial cases carrying a 22q11.2 deletion.Methods
Thirty-two 22q11.2DS subjects among 26 families were enrolled.Results
Second generation subjects showed a significantly higher number of features than their transmitting parents (212 vs 129, P?=?0.0015). Congenital heart defect, calcium-phosphorus metabolism abnormalities, developmental and speech delay were more represented in the second generation (P?<?0.05). Ocular disorders were more frequent in the parent group. No significant difference was observed for the other clinical variables. Intrafamilial phenotypic heterogeneity was identified in the pedigrees. In 23/32 families, a higher number of features were found in individuals from the second generation and a more severe phenotype was observed in almost all of them, indicating the worsening of the phenotype over generations. Both genetic and epigenetic mechanisms may be involved in the phenotypic variability.Conclusions
Second generation subjects showed a more complex phenotype in comparison to those from the first generation. Both ascertainment bias related to patient selection or to the low rate of reproductive fitness of adults with a more severe phenotype, and several not well defined molecular mechanism, could explain intergenerational and intrafamilial phenotypic variability in this syndrome. 相似文献59.
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