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41.
Jones CM Athanasiou T Dunne N Kirby J Aziz O Haq A Rao C Constantinides V Purkayastha S Darzi A 《The Annals of thoracic surgery》2007,83(1):341-348
Multi-detector computed tomography (MDCT) has become an alternative to coronary angiography in diagnosis of graft occlusion and stenosis after coronary artery bypass. A literature search was performed for studies comparing angiography to 8-slice, 16-slice, and 64-slice MDCT in the assessment of coronary grafts. In assessing occlusion, 14 studies produced pooled sensitivity of 97.6%, specificity of 98.5%, diagnostic odds ratio of 934.2, area under the curve of 0.996, and Q* of 0.977. Ninety-six percent of all grafts were visualized for occlusion assessment. Beta blockers, symptomatic status, and postoperative period did not significantly affect diagnostic performance. Stenosis assessment produced sensitivity of 88.7% and specificity of 97.4%. Eighty-eight percent of patent grafts could be assessed for stenosis. The diagnostic accuracy of MDCT approaches angiography for diagnosing graft occlusion and stenosis in patients with venous and arterial coronary bypass grafts. Our findings show that cardiac surgeons will need to interpret MDCT images of both native and grafted vessels soon in preparation for primary or re-do coronary bypass grafting procedures. 相似文献
42.
Giorgos L. Chouliaras Antonis Kattamis Vasilis Berdoukas Efstathios D. Gotsis Sophie Mavrogeni Vassilis Ladis 《British journal of haematology》2010,151(4):397-401
Cardiac Magnetic Resonance (CMR) has replaced all other surrogate measurements in the determination of transfusional cardiac iron overload in patients with thalassaemia major. We aimed to determine the diagnostic value of CMR T2* with respect to cardiac dysfunction (CD) as determined by CMR‐derived left ventricular ejection fraction (LVEF). Cardiac T2* values and LVEF measured by CMR were recorded in 303 patients with thalassaemia major, at the time of their first CMR. T2* was correlated with LVEF (regression coefficient: 0·57, P < 0·001). The prevalence of CD was 32·9% in patients with T2* ≤ 8 ms, 12·5% in patients with T2* > 8 ms and ≤14 ms and reduced to 9·1% in patients with T2* between 14–20 ms. As the probability of CD is progressively, and not suddenly, reduced with increasing values of T2*, CMR has a limited diagnostic value for CD (Receiver operating characteristic analysis, area under the curve = 0·68). Patients with cardiac T2* ≤ 8 ms require careful and intensive management. This risk decreases with increasing values of T2* but even in mildly loaded patients the probability of impaired LVEF is not negligible. 相似文献
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Contribution of acquired immunodeficiency syndrome/human immunodeficiency virus (HIV) infection to pregnancy mortality rates is difficult to estimate; however, it appears to be one of the leading causes of death, at least in developing countries. Prenatal HIV testing affords the best opportunity for the prevention of perinatal HIV transmission. Rapid HIV testing substantially increases the proportion of women who obtain HIV results compared with conventional enzyme-linked immunosorbent assay testing, thus maximizing perinatal HIV interventions. Pregnancy appears to have no effect on the course of HIV disease. Infections due to a variety of pathogens influence the clinical course of the HIV infection and may complicate pregnancy and increase maternal mortality. The main risk factors for mother-to-child HIV transmission are high maternal viral load and CD4 cell count <700 cells/mm3. The main protective factor is antiretroviral therapy. 相似文献
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Efstathios D. Pagourelias Ph.D. Georgios K. Efthimiadis Ph.D. Evangelia Kouidi Ph.D. Paraskevi Zorou M.Sc. Georgios Giannoglou Ph.D. Asterios Deligiannis Ph.D. Vasilis G Athyros Ph.D. Asterios Karagiannis Ph.D. Paraschos Geleris Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(2):131-139
Left ventricular hypertrophy (LVH) with intraventricular septum thickness (IVST) between 1.2 and 1.5 cm in athletes represents a “gray zone” between physiologic adaptation and mild hypertrophic cardiomyopathy (HCM). Various echo and laboratory parameters have been reported till now in the literature to discriminate the “gray zone” entities. Aim of this study was to assess the efficacy of these “classic” parameters in differentiating physiologic LVH in athletes from mild HCM in a highly selected population. Nine highly trained athletes with IVST (1.28 ± 0.07 cm), 9 patients with mild HCM (1.38 ± 0.11 cm), and 26 athletes without LVH (1.06 ± 0.09 cm; P < 0.0005) underwent echocardiographic study, cardiopulmonary treadmill exercise stress test, and brain natriuretic peptide (BNP) measurement before and after exercise. Among all parameters tested, 7 were found to significantly differ between “gray zone” groups. After bootstrapping analysis, it was found that athletes with left ventricular end‐diastolic diameter <4.74 cm, mitral deceleration time >200 ms, isovolumic relaxation time >94 ms, tricuspid E/A < 1.63, septum Em < 9.5 cm/sec, relative wall thickness >0.445, and a BNP value at rest >9.84 pg/mL had a greater possibility for having underlying cardiomyopathy. A 10‐point score based on these parameters showed accuracy (area under the curve = 0.958 [95%CI: 0.738–1.0; P = 0.00005, standard error = 0.0342]) for revealing HCM in a gray zone athletic population. Differentiation of adaptive LVH versus HCM in a gray zone population could be facilitated by recognition of certain features referring to LV dimensions, diastolic function, and BNP. 相似文献
49.
Hope Caughron Dennis Kim Norihiko Kamioka Stamatios Lerakis Altayyeb Yousef Aneesha Maini Shawn Reginauld Anurag Sahu Subhadra Shashidharan Maan Jokhadar Fred H. Rodriguez Wendy M. Book Michael McConnell Peter C. Block Vasilis Babaliaros 《JACC: Cardiovascular Interventions》2018,11(24):2495-2503
Objectives
This study compares 30-day, 1-year, and 3-year echocardiographic findings and clinical outcomes of transcatheter pulmonary valve-in-valve replacement (TPVR) and repeat surgical pulmonary valve replacement (SPVR).Background
In patients with adult congenital heart disease and previous pulmonary valve replacement (PVR) who require redo PVR, it is unclear whether TPVR or repeat SPVR is the preferred strategy.Methods
We retrospectively identified 66 patients (TPVR, n = 36; SPVR, n = 30) with bioprosthetic pulmonary valves (PVs) who underwent either TPVR or repeat SPVR at Emory Healthcare from January 2007 to August 2017.Results
The TPVR cohort had fewer men and more patients with baseline New York Heart Association (NYHA) functional class III or IV. There was no difference in mortality, cardiovascular readmission, or post-procedural PV reintervention at 30 days, 1 year, or 3 years. Post-procedural echocardiographic findings showed no difference in mean PV gradients between the TPVR and SPVR groups at 30 days, 1 year, or 3 years. In the TPVR cohort, there was less right ventricular dysfunction at 30 days (2.9% vs. 46.7%; p < 0.01), despite higher baseline NYHA functional class in the SPVR cohort.Conclusions
In patients with bioprosthetic PV dysfunction who underwent either TPVR or SPVR, there was no difference in mortality, cardiovascular readmission, or repeat PV intervention at 30 days, 1 year, or 3 years. Additionally, TPVR and SPVR had similar intermediate-term PV longevity, with no difference in PV gradients or PVR. The TPVR cohort also had less right ventricular dysfunction at 30 days despite a higher baseline NYHA functional classification. These intermediate-term results suggest that TPVR may be an attractive alternative to SPVR in patients with previous bioprosthetic surgical PVs. 相似文献50.