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131.

Purpose

To assess the feasibility and reproducibility of real‐time radial kt sensitivity encoding (SENSE) magnetic resonance imaging (MRI) for biventricular volumetric assessment during exercise.

Materials and Methods

In all, 12 healthy young adults underwent MRI at rest and during supine exercise at three different workload intensities. Biventricular volumes and function were assessed with 1) a radial kt SENSE real‐time sequence and 2) a scanner vendor supplied (standard) real‐time sequence. Global image quality, motion fidelity, and agreement in right ventricular (RV) and left ventricular (LV) stroke volume (SV) as a surrogate measure for accuracy were assessed. Exercise MR was repeated within 1 month for assessment of reproducibility.

Results

Imaging scores were superior for radial real‐time kt SENSE images (P < 0.001). Agreement in RV and LV SV during exercise was better with radial kt real‐time (SD of difference ±3.43 vs. ±8.97 mL; P < 0.001). Agreement in cardiac output (CO) in the same subject at two different imaging sessions was better for radial kt SENSE. This was significant for the CO calculated for the RV (SD of difference ±0.6 vs. ±0.95 L/min; P = 0.01) and LV (±0.45 vs. ±0.92 L/min; P < 0.001).

Conclusion

Radial kt SENSE real‐time imaging represents a feasible and reproducible imaging technique for biventricular assessment during exercise. J. Magn. Reson. Imaging 2009;29:1062–1070. © 2009 Wiley‐Liss, Inc.  相似文献   
132.
Nucleosome core particles have been efficiently assembled in vitro by direct interaction of histones and DNA at physiological ionic strength, as assayed by digestion with DNases, supercoiling of relaxed circular DNA, and electron microscopy. Reconstitution was achieved either by the simultaneous addition of all core histones, or by the sequential binding of H3 . H4 tetramer and H2A . H2B dimer to DNA. Micrococcal nuclease digestion and electron microscopy studies indicated that there is heterogeneity in the spacings at which core particles are assembly on the DNA. Length measurements of oligomeric DNA produced during the course of the digestion suggest that the core histone octamer can organize 167 (+/- 4) rather than 145 base pairs of DNA, the extra 20 base pairs being quickly digested. Binding of histone H1 to core particles resulted in the protection of about 165 base pairs of DNA from nuclease attack. Because the core histone octamer is fully dissociated into H3 . H4 tetramer and H2A . H2B dimer at physiological ionic strength, our results would suggest that in vivo core particle assembly may also occur by interaction of these two complexes on the nascent DNA.  相似文献   
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135.
The incidence of coronary artery disease (CAD) is greater in men than in women. The aim of the study was to analyze whether any gender-related differences in patients with CAD and documented spontaneous sustained ventricular tachyarrhythmias exist, and which parameters influence the induction of sustained ventricular tachyarrhythmias. The data of 250 patients [43 women (17.2%) and 207 men (82.8%)] with spontaneous sustained ventricular tachycardia [n = 190 (76%)] and fibrillation [n = 60 (24%)] who underwent coronary and left ventricular angiography, electrophysiological study, and signal-averaging electrocardiogram (ECG) form the basis of this analysis. No gender-related differences could be observed in age, number of diseased coronary arteries, history, location and number of myocardial infarctions, presence of left ventricular aneurysm, ejection fraction, type of spontaneous or induced arrhythmias, right ventricular effective refractory period, and signal-averaged ECG parameters. Age, presence of previous myocardial infarction, and ejection fraction were significant predictors (p<0.001) of inducibility of sustained ventricular tachyarrhythmias. Once CAD has begun, female and male patients present similar clinical and electrophysiologic characteristics. Thus, both genders should benefit similarly from diagnostic and therapeutic approaches if they are referred to the hospital or to invasive interventions at similar intervals in the course of their illness.  相似文献   
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137.
Due to its high prevalence, atopic dermatitis is an important problem in the dermatologic practice. The chronicity of the disease together with numerous triggering factors of varying individual impact create a complex situation which is difficult to manage under the current circumstances in our health care system. We describe the concept of an outpatient clinic especially for atopic dermatitis as established in our Department of Dermatology. A high degree of standardization is combined with a high measure of individual care. The aims of this clinic are an optimized outpatient management of atopic dermatitis, the gathering of epidemiologic data, the performance of controlled studies, and potentially the reduction of costs.  相似文献   
138.
Granulomatous cheilitis and Crohn's disease in a 3-year-old boy   总被引:1,自引:0,他引:1  
Granulomatous cheilitis and Crohn's disease are disorders of unknown etiology. There are case reports describing their coincidence and pointing out the necessity of ruling out systemic disorders once the diagnosis of granulomatous cheilitis is made. However, such reports are few and the causal association of both diseases is controversial in the literature. We report the youngest patient so far, a 3-year-old boy, who had granulomatous cheilitis and Crohn's disease simultaneously. This coincidence so early in life strongly suggests that both represent manifestations of the same disease.  相似文献   
139.

Objectives

The present study aimed to test the clinical benefit of combined transcatheter mitral plus tricuspid valve edge-to-edge repair (TMTVR) as compared with transcatheter mitral valve edge-to-edge repair (TMVR) alone in patients with both significant mitral (MR) and tricuspid regurgitation (TR) at high surgical risk.

Background

A growing number of patients with severe MR at increased surgical risk are treated by transcatheter techniques. Evidence suggests that residual TR remains a predictor of adverse outcome in these patients.

Methods

Sixty-one patients (mean age 79.5 ± 8.4 years, EuroSCORE II 8.6 ± 5.9%) underwent TMTVR (n = 27) or TMVR (n = 34). Echocardiographic and cardiac magnetic resonance imaging was performed before and after the procedure.

Results

Reduction of MR was similar in patients undergoing TMTVR and TMVR. Effective regurgitant orifice area of TR was reduced from 0.51 to 0.29 cm2 in patients with TMTVR (p < 0.01), but remained unchanged after TMVR. On cardiac magnetic resonance imaging, only patients in the TMTVR group exhibited improved effective right and left ventricular stroke volume, and increased cardiac index (2.1 vs. 2.5 l/min/m2; p < 0.01). TMTVR led to superior improvement in New York Heart Association functional class, NT-proBNP levels, and 6-min walking distance as compared with TMVR. After up to 18 months of follow-up, patients with TMTVR experienced fewer hospitalizations for heart failure when compared with patients with TMVR (p = 0.02), whereas rates of death were comparable between both groups of patients.

Conclusions

TMTVR appears superior to TMVR in terms of cardiac output and functional improvement early after the intervention, and improves clinical outcome up to 18 months of follow-up.  相似文献   
140.
ObjectivesThe purpose of this observational first-in-human experience was to investigate the feasibility and safety of the PASCAL transcatheter valve repair system and its impact on short-term clinical outcomes in patients with severe tricuspid regurgitation (TR).BackgroundTranscatheter repair of severe TR is a promising treatment option for patients at prohibitive surgical risk. Large leaflet coaptation gaps and tethering represent common features that challenge the application of transcatheter repair techniques.MethodsTwenty-eight patients with severe TR were treated with the PASCAL system in a compassionate use experience at 6 sites. All patients had heart failure due to severe TR and were deemed at high surgical risk by institutional heart teams. The primary outcome was procedural success, defined as the implantation of at least 1 device with post-procedural TR grade ≤2+, without mortality or conversion to surgery.ResultsAll patients (mean age 78 ± 6 years, 54% women) were at high surgical risk (mean European System for Cardiac Operative Risk Evaluation II score 6.2 ± 5.2%). TR etiology was functional in 92%, with mean tricuspid annular diameter of 49.5 ± 6 mm and mean coaptation gap of 6.9 ± 3 mm. Procedural success was 86%, with 1.4 ± 0.6 devices implanted per patient. There were no intraprocedural complications. At 30-day follow-up, mortality was 7.1%, 88% of patients were in New York Heart Association functional class I or II, with TR grade ≤2+ in 85%. There were 2 single-leaflet device attachments, which were managed conservatively. Six-min walk distance improved from 240 m (interquartile range: 172 to 337 m) to 335 m (interquartile range: 251 to 385 m) (p < 0.001).ConclusionsThis first-in-human experience evaluating transcatheter tricuspid repair with the PASCAL system demonstrated high procedural success, acceptable safety, and significant clinical improvement. Larger prospective studies with long-term follow-up are needed to confirm these initial promising results and further define the impact of PASCAL tricuspid repair on clinical outcomes.  相似文献   
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