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101.
Acute coronary syndromes (ACS) without persistent ST-segment elevation are the main cause of hospitalization, morbidity and mortality. The objective of this study was to compare clinical and angiographic parameters as well as in-hospital results of treating 307 consecutive patients with ACS without persistent ST-segment elevation with either PCI or CABG. Inclusion criteria were: rest angina within the last 24 hours, ST-segment depression (> 0.5 mm), T-wave inversion (> 1 mm) in at least two leads, positive serum cardiac markers. PCI was performed in 75.9% of patients and 24.1% of patients underwent CABG. Both groups did not differ as to age, sex, history of diabetes, arterial hypertension, heart failure, smoking and ejection fraction. Positive troponin was significantly more frequent in the PCI group. 51% of PCI patients and 80% of CABG patients had complete revascularization (p = 0.00001). Independent predictors of in-hospital death in the CABG group were: inability to determine culprit vessel during coronary angiography due to lesions' severity (OR 13.65; 95% CI 9.40-15.20; p = 0.007) and heart failure (OR 15.58; 95% CI 12.29-18.01; p = 0.003). In the PCI group these independent predictors were: Braunwald's IIIC unstable angina (OR 5.48; 95% CI 3.10-7.17; p = 0.04) and diabetes (OR 2.22; 95% CI 1.07-3.90; p = 0.003). In-hospital mortality rate was significantly higher in the CABG group (8.1% vs 1.7% p < 0.01). Patients with multivessel coronary artery disease and ACS without ST-segment elevation treated with PCI have better in-hospital outcome than patients assigned to CABG, but the rate of complete revascularization is lower.  相似文献   
102.
The molecular genetic basis for hypertrophic cardiomyopathy   总被引:48,自引:0,他引:48  
Hypertrophic cardiomyopathy (HCM), a relatively common disease, is diagnosed clinically by unexplained cardiac hypertrophy and pathologically by myocyte hypertrophy, disarray, and interstitial fibrosis. HCM is the most common cause of sudden cardiac death (SCD) in the young and a major cause of morbidity and mortality in elderly. Hypertrophy and fibrosis are the major determinants of morbidity and SCD. More than 100 mutations in nine genes, all encoding sarcomeric proteins have been identified in patients with HCM, which had led to the notion that HCM is a disease of contractile sarcomeric proteins. The beta -myosin heavy chain (MyHC), cardiac troponin T (cTnT) and myosin binding protein-C (MyBP-C) are the most common genes accounting for approximately 2/3 of all HCM cases. Genotype-phenotype correlation studies suggest that mutations in the beta -MyHC gene are associated with more extensive hypertrophy and a higher risk of SCD as compared to mutations in genes coding for other sarcomeric proteins, such as MyBP-C and cTnT. The prognostic significance of mutations is related to their hypertrophic expressivity and penetrance, with the exception of those in the cTnT, which are associated with mild hypertrophic response and a high incidence of SCD. However, there is a significant variability and factors, such as modifier genes and probably the environmental factors affect the phenotypic expression of HCM. The molecular pathogenesis of HCM is not completely understood. In vitro and in vivo studies suggest that mutations impart a diverse array of functional defects including reduced ATPase activity of myosin, acto-myosin interaction, cross-bridging kinetics, myocyte contractility, and altered Ca2+ sensitivity. Hypertrophy and other clinical and pathological phenotypes are considered compensatory phenotypes secondary to functional defects. In summary, the molecular genetic basis of HCM has been identified, which affords the opportunity to delineate its pathogenesis. Understanding the pathogenesis of HCM could provide for genetic based diagnosis, risk stratification, treatment and prevention of cardiac phenotypes.  相似文献   
103.
Purpose: This article aims to clarify the current state-of-the-art of robotic/mechanical devices for post-stroke thumb rehabilitation as well as the anatomical characteristics and motions of the thumb that are crucial for the development of any device that aims to support its motion.

Methods: A systematic literature search was conducted to identify robotic/mechanical devices for post-stroke thumb rehabilitation. Specific electronic databases and well-defined search terms and inclusion/exclusion criteria were used for such purpose. A reasoning model was devised to support the structured abstraction of relevant data from the literature of interest.

Results: Following the main search and after removing duplicated and other non-relevant studies, 68 articles (corresponding to 32 devices) were left for further examination. These articles were analyzed to extract data relative to (i) the motions assisted/permitted – either actively or passively – by the device per anatomical joint of the thumb and (ii) mechanical-related aspects (i.e., architecture, connections to thumb, other fingers supported, adjustability to different hand sizes, actuators – type, quantity, location, power transmission and motion trajectory).

Conclusions: Most articles describe preliminary design and testing of prototypes, rather than the thorough evaluation of commercially ready devices. Defining appropriate kinematic models of the thumb upon which to design such devices still remains a challenging and unresolved task. Further research is needed before these devices can actually be implemented in clinical environments to serve their intended purpose of complementing the labour of therapists by facilitating intensive treatment with precise and repeatable exercises.
  • Implications for Rehabilitation
  • Post-stroke functional disability of the hand, and particularly of the thumb, significantly affects the capability to perform activities of daily living, threatening the independence and quality of life of the stroke survivors. The latest studies show that a high-dose intensive therapy (in terms of frequency, duration and intensity/effort) is the key to effectively modify neural organization and recover the motor skills that were lost after a stroke. Conventional therapy based on manual interaction with physical therapists makes the procedure labour intensive and increases the costs.

  • Robotic/mechanical devices hold promise for complementing conventional post-stroke therapy. Specifically, these devices can provide reliable and accurate therapy for long periods of time without the associated fatigue. Also, they can be used as a means to assess patients? performance and progress in an objective and consistent manner.

  • The full potential of robot-assisted therapy is still to be unveiled. Further exploration will surely lead to devices that can be well accepted equally by therapists and patients and that can be useful both in clinical and home-based rehabilitation practice such that motor recovery of the hand becomes a common outcome in stroke survivors.

  • This overview provides the reader, possibly a designer of such a device, with a complete overview of the state-of-the-art of robotic/mechanical devices consisting of or including features for the rehabilitation of the thumb. Also, we clarify the anatomical characteristics and motions of the thumb that are crucial for the development of any device that aims to support its motion.

  • Hopefully, this?combined with the outlined opportunities for further research?leads to the improvement of current devices and the development of new technology and knowledge in the field.

  相似文献   
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