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991.
992.
Sylvia SM Chen Jennifer Keegan Andrew W Dowsey Tevfik Ismail Ricardo Wage Wei Li Guang-Zhong Yang David N Firmin Philip J Kilner 《Journal of cardiovascular magnetic resonance》2011,13(1):80
Background
Right ventricular ejection fraction (RV-EF) has traditionally been used to measure and compare RV function serially over time, but may be a relatively insensitive marker of change in RV myocardial contractile function. We developed a cardiovascular magnetic resonance (CMR) tagging-based technique with a view to rapid and reproducible measurement of RV long axis function and applied it in patients with congenital heart disease.Methods
We studied 84 patients: 56 with repaired Tetralogy of Fallot (rTOF); 28 with atrial septal defect (ASD): 13 with and 15 without pulmonary hypertension (RV pressure > 40 mmHG by echocardiography). For comparison, 20 healthy controls were studied. CMR acquisitions included an anatomically defined four chamber cine followed by a cine gradient echo-planar sequence in the same plane with a labelling pre-pulse giving a tag line across the basal myocardium. RV tag displacement was measured with automated registration and tracking of the tag line together with standard measurement of RV-EF.Results
Mean RV displacement was higher in the control (26 ± 3 mm) than in rTOF (16 ± 4 mm) and ASD with pulmonary hypertension (18 ± 3 mm) groups, but lower than in the ASD group without (30 ± 4 mm), P < 0.001. The technique was reproducible with inter-study bias ± 95% limits of agreement of 0.7 ± 2.7 mm. While RV-EF was lower in rTOF than in controls (49 ± 9% versus 57 ± 6%, P < 0.001), it did not differ between either ASD group and controls.Conclusions
Measurements of RV long axis displacement by CMR tagging showed more differences between the groups studied than did RV-EF, and was reproducible, quick and easy to apply. Further work is needed to assess its potential use for the detection of longitudinal changes in RV myocardial function. 相似文献993.
Akihisa KataokaNobusada Funabashi Akiyo TakahashiRei Yajima Maiko TakahashiMasae Uehara Hiroyuki TakaokaMariko Saito Chiharu YamaguchiKwangho Lee Fumio NomuraIssei Komuro 《International journal of cardiology》2011,153(1):47-54
Purpose
To evaluate efficacy and reproducibility of 320-slice computed tomography (CT) for measuring left atrial (LA) maximum (LAVmax) and minimum volume (LAVmin) during the cardiac cycle, we compared CT with three- and two-dimensional (3D and 2D) transthoracic echocardiogram (TTE).Materials and methods
LAVmax and LAVmin (ml), and LA ejection fraction (LAEF) (%) were assessed in 22 consecutive subjects (15 males, 59.5 ± 15.1 years) using retrospective electrocardiogram gated 320-slice CT (Aquilion One, Toshiba Medical) and 3D-TTE (IE-33, Phillips). LAVmax and LAVmin were selected from the time volume curve. LAEF was calculated as (LAVmax − LAVmin)/LAVmax × 100(%).Results
Mean ± standard deviation (SD) of LAVmax and LAV min were significantly larger by CT than 3D-TTE or 2D-TTE (both P < 0.01). LAEF was 25.3 ± 13.1% by CT, 30.2 ± 6.8% by 3D-TTE (P = NS) and 33.9 ± 8.9% by 2D-TTE (P < 0.05). The correlation coefficients (CCs) between CT and 3D-TTE in LAVmax, LAmin, and LAEF were 0.64, 0.68 and 0.57, respectively. Mean difference ± 1.96SD of LAVmax, LAVmin and LAEF by Bland and Altman analysis calculated from CT minus 3D-TTE were 48.8 ± 59.1 ml, 41.1 ± 63.2 ml, and −4.9 ± 21.1%, respectively. The CCs and mean difference ± 1.96SD between CT and 2D-TTE had similar tendencies. The CCs of interobserver variation were (for CT, 3D-TTE, 2D-TTE, respectively): 0.90, 0.95 and 0.94 (LAVmax), 0.97 and 0.97 and 0.93 (LAVmin), and 0.64, 0.77 and 0.34 (LAEF).Conclusions
320-slice CT enables direct LAV measurements and has high reproducibility and positive correlation with 3D and 2D TTE. Absolute value of LAV by CT was larger than that by 3D and 2D TTE. 相似文献994.
Victoria PolyakovaIvo Loeffler Stefan HeinShigeru Miyagawa Izabela PiotrowskaSebastian Dammer Juha RisteliJutta Schaper Sawa Kostin 《International journal of cardiology》2011,151(1):18-33
Objectives
We studied fibrosis, collagen metabolism, MMPs/TIMPs and cytokine expression in various forms of human heart failure (HF) by quantitative immunofluorescent microscopy, Western blot, zymography, RT-PCR and in situ hybridization. In explanted human hearts with HF due to either dilated (DCM, n = 6) or ischemic (ICM-BZ-borderzone, ICM-RZ-remote zone, n = 7) or inflammatory (myocarditis, MYO, n = 6) cardiomyopathy and 8 controls MMP2, 8, 9, 19, and TIMP1, 2, 3, 4 as well as procollagens I and III (PINP, PIIINP), mature collagen III (IIINTP) and the cross-linked collagen I degradation product (ICTP) were measured.Results
In comparison with controls, MMPs and TIMPs were significantly upregulated ranging (from highest to lowest) from ICM-BZ, DCM, ICM-RZ, MYO for all MMPs with the exception of MMP9 (highest in DCM), and for TIMPs from ICM-BZ, ICM-RZ, DCM and MYO. MMP2 and 9 were activated in all groups. The TIMP/MMP ratio was 1.3 for control, 1.9 in ICM-BZ (TIMP > MMP) and lowered to 1.0 in the other groups. Collagen I/collagen III ratio correlated significantly with the decrease in LVEDP. PINP was higher than ICTP in all groups. PIIINP elevation was present in DCM and ICM-RZ and IIINTP was up to 4-fold augmented in all groups. Fibrosin mRNA was upregulated in ICM-BZ, activin A in MYO but FGF1 and FGF2 remained unchanged. ANP mRNA was increased in all groups.Conclusions
Although different degrees of severity of collagen metabolism, MMP/TIMP imbalance and cytokine expression in diverse forms of HF are present, the end product is collagen deposition. These findings suggest multiple mechanisms acting alone or in concert in fibrosis development in HF. 相似文献995.
Hitesh PatelBaris A. Ozdemir Mitesh PatelHan B. Xiao Philip A. Poole-Wilson Stuart D. Rosen 《International journal of cardiology》2011,151(1):34-39
Background
Autonomic dysfunction (AD) is associated with morbidity and mortality in patients with systolic heart failure (SHF). The extent of AD when LV ejection fraction is preserved (HF-NEF), is unclear. Our objectives were: 1) quantitative assessment of autonomic function in SHF and HF-NEF; and 2) exploration of relationships among AD, symptoms and cardiac function.Methods
This was an observational study of patients newly referred from primary care with a heart failure diagnosis; 21 SHF, 20 HF-NEF patients and 21 normal subjects were recruited. All subjects underwent clinical evaluation, 6-minute walk test (6MWT), Minnesota Questionnaire (MLWHFQ) and echocardiography. Autonomic assessment included haemodynamic responses to standing, deep breathing and handgrip. Concomitant blood pressure variability (BPV) and heart rate variability (HRV) parameters were also derived.Results
There were significant differences in all haemodynamic responses between SHF, HF-NEF and normal. Log transformed (ln) low frequency spectral component of BPV was lower in SHF (4.1 ± 0.3) than HF-NEF (4.2 ± 0.4) and normal (4.4 ± 0.1; p = 0.001 SHF vs HF-NEF and vs normal). Ln LF/HF was greater in normal than HF-NEF and SHF (1.5 ± 0.7 vs 0.9 ± 1.0 vs 0.6 ± 0.6; p = 0.003). Autonomic modulations correlated negatively with severity of heart failure.Conclusions
Autonomic responses in heart failure were blunted and the attenuation of responses correlated strongly with symptomatic and functional markers of disease severity. Autonomic dysfunction is a feature of the heart failure syndrome but is not dependent on ejection fraction. 相似文献996.
997.
Orcajo B Muruzabal F Isasmendi MC Gutierrez N Sánchez M Orive G Anitua E 《Diabetes research and clinical practice》2011,93(2):e65-e67
A 71 year old person with diabetes with a severe mal perforant ulcer in the right foot was treated twice with autologous plasma-rich in growth factors (PRGF) obtained from her own blood. After PRGF treatment the severe mal perforant ulcer completely healed in 10 weeks. 相似文献
998.
999.
1000.
Although orthotopic heart transplantation is the gold standard for definitive surgical treatment of end-stage heart failure, other operative therapies exist for dealing with severe systolic left ventricular dysfunction. The choice of surgical intervention depends on the etiology and functional characteristics of the patient's ventricular dysfunction. In patients with ischemic cardiomyopathy, surgical revascularization improves survival. Patients with mitral regurgitation experience significant functional improvement from mitral valve repair and replacement. In patients with aortic valve dysfunction, aortic valve replacement results in improved survival and functional status. Although surgical ventricular reconstruction is controversial, significant data exist suggesting that it is an effective therapy in a subset of patients with left ventricular dysfunction. Finally, passive restraint devices are effective at halting further ventricular dilation. Although cardiac surgery in patients with severe ventricular dysfunction can be complicated by significant morbidity and mortality, experienced centers have demonstrated acceptable outcomes in carefully selected patients. 相似文献