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1.
For patients with coronary artery disease and left ventricular dysfunction who undergo revascularization, it is important to estimate the left ventricular ejection fraction (LVEF) improvement after revascularization, as this is a strong indicator of the long-term outcome. Identification of viable segments from echocardiography has been considered a predictive sign of LVEF improvement. However, a quantitative relation between segmental function recovery and global ejection fraction improvement has not been established. There is a clinical need to determine parameters that are predictive to LVEF improvement. A cylindrical left ventricular model is proposed to establish the relation between segmental myocardial function and LVEF based on a 12-segment echocardiograph model. Model results show that LVEF improvement is directly related to the contraction ratio in normal segments and a weighted sum of the number of viable segments that recover to normal or hypokinetic, which is equal to a weighted sum of the change in wall motion scores. This new combined parameter is a better predictor of the amount of LVEF improvement than the total number of viable segments or preoperative ejection fraction. The predictive value of the model was illustrated in a group of four patients with coronary artery disease who underwent revascularization.  相似文献   
2.
Non-invasive imaging plays a growing role in the diagnosis and management of ischemic heart disease from its earliest manifestations of endothelial dysfunction to myocardial infarction along the myocardial ischemic cascade. Experts representing the North American Society for Cardiovascular Imaging and the European Society of Cardiac Radiology have worked together to organize the role of non-invasive imaging along the framework of the ischemic cascade. The current status of non-invasive imaging for ischemic heart disease is reviewed along with the role of imaging for guiding surgical planning. The issue of cost effectiveness is also considered. Preclinical disease is primarily assessed through the coronary artery calcium score and used for risk assessment. Once the patient becomes symptomatic, other imaging tests including echocardiography, CCTA, SPECT, PET and CMR may be useful. CCTA appears to be a cost-effective gatekeeper. Post infarction CMR and PET are the preferred modalities. Imaging is increasingly used for surgical planning of patients who may require coronary artery bypass.  相似文献   
3.
BACKGROUND: Impaired left ventricular diastolic function is a common finding in essential hypertension. METHODS: In order to investigate possible relationships between flow velocity through the mitral valve (E/A; index of left ventricular diastolic function) and 24-hour blood pressure and heart rate variations, 198 patients with mild to moderate essential hypertension were studied by Doppler echocardiography and ambulatory blood pressure monitoring. They were divided according to age into group 1 (n = 88, age 40-54 years) and group 2 (n = 110, age 55-79 years). Each group was divided into subgroups with (1a, 2a) or without (1b, 2b) left ventricular hypertrophy according to the end-diastolic posterior wall thickness and/or the interventricular septum thickness. RESULTS: In a multivariate stepwise regression analysis, age (beta = -0.25, p < 0.0001), posterior wall thickness (beta = -0.31, p < 0.0057) and mean heart rate during the day (beta = -0.34, p < 0.0284) were the independent predictors of E/A in the pooled population. In group 1a (young subjects with left ventricular hypertrophy), mean systolic blood pressure during the night (beta = -0.33, p < 0.041) was the only independent predictor of E/A. In the elderly group without left ventricular hypertrophy (group 2b), the mean heart rate during the day (beta = -0.44, p < 0.0000) and mean pulse pressure during the night (beta = -0.60, p < 0.0007) were the independent predictors of E/A. CONCLUSIONS: The new finding provided by this study is that in elderly hypertensive patients without left ventricular hypertrophy, a large pulse pressure at night may serve as an independent predictor of abnormal left ventricular diastolic filling.  相似文献   
4.
BACKGROUND: The percutaneous left atrial appendage transcatheter occlusion system (PLAATO) is an alternative to coumadin in patients with atrial fibrillation (AF) and contraindications to anticoagulation. It appears to be protective against stroke in intermediate follow-up studies. Hypothesis: The PLAATO system is protective against stroke and is safe in long-term follow-up. METHODS: Eleven patients (age 72 +/- 9 years) enrolled in the PLAATO feasibility and safety trial at our institution were followed (36 +/- 1.4) months. All patients had contraindications to anticoagulation and had at least one risk factor for stroke. The predicted stroke risk for this cohort was 8.6% per year as calculated using the CHADS2 score (A validated scoring system assigning 1 point for CHF, hypertension, diabetes, and age >75 years, and 2 points for history of stroke). The primary end-point was the incidence of stroke, and secondary end points were complications related to PLAATO device and systemic embolic events. RESULTS: There was one stroke during follow-up; the stroke risk in our population was 3% per year. Interestingly, the observed stroke risk in these patients after occluding the left atrial appendage is comparable to what would have been observed with warfarin. No systemic embolic events were noted in our cohort and no long term complications related to PLAATO were seen. CONCLUSION: The PLAATO device decreases the risk of stroke in a high-risk cohort of AF patients. Furthermore, the safety of this device is confirmed during this long-term follow-up study. A larger trial is needed to validate these findings.  相似文献   
5.
Aortic valve abscesses (AVAs) are a devastating complication of aortic valve endocarditis. Over 8 years, 25 patients were diagnosed with AVA by transesophageal echo (TEE). Management and outcomes were then analyzed. Eleven (44%) AVAs involved prosthetic valves, and 6 (24%) occurred in congenitally malformed valves. Twenty patients (80%) underwent surgical intervention; the rest were treated medically. Eleven (44%) of the patients died [6 (30%) surgery patients and all the medical patients]. Eight of 11 (73%) patients who died were culture positive for Staphylococcus aureus. All patients with congenitally malformed aortic valves underwent surgical intervention and survived. We conclude that: (1) despite advances in therapy and diagnosis, patients with AVAs have a high mortality rate; (2) prognosis with AVA is especially poor when S aureus is the infectious organism; (3) patients with AVAs in congenitally malformed valves have a great outcome with surgery; (4) patients treated medically have a very poor prognosis; earlier identification by TEE may be critical to improving survival.  相似文献   
6.
BACKGROUND: L-Arginine is a nitric oxide precursor, which augments endothelium-dependent vasodilatation in hypercholesterolemic humans and animals. Endothelium-dependent vasodilation is attenuated in patients with hypertension; however the effects of oral L-arginine on endothelial function of the conduit arteries in patients with essential hypertension have not previously been investigated. METHODS: In a prospective randomized double blind trial, 35 patients with essential hypertension received either 6 g L-arginine (18 subjects) or placebo (17 subjects). Patients were examined for flow-mediated endothelium-dependent dilatation of the brachial artery before and 1.5 h after administration of L-arginine or placebo. At the end of the protocol the nitrate-induced, endothelium-independent vasodilatation was evaluated. RESULTS: Two groups of L-arginine and placebo were similar regarding age, sex, blood lipids, smoking, diabetes, coronary artery disease, body mass index, intima-media thickness of the common carotid artery, clinics blood pressure and baseline brachial artery parameters. Administration of L-arginine or placebo did not change significantly heart rate, blood pressure, baseline diameter, blood flow or reactive hyperemia. L-Arginine resulted in a significant improvement of flow-mediated dilatation (1.7+/-3.4 vs. 5.9+/-5.4%, P=0.008) while placebo did not significantly change this parameter (3.0+/-2.7 vs. 3.1+/-2.2%, P=ns). The effect of L-arginine on flow-mediated dilatation was significantly different from the effect of placebo (P=0.05). L-Arginine did not significantly influence nitrate-induced dilatation (16+/-6.9 vs. 17.7+/-6.7%, P=ns). CONCLUSIONS: Oral administration of L-arginine acutely improves endothelium-dependent, flow-mediated dilatation of the brachial artery in patients with essential hypertension. The long-term effects of L-arginine in these patients require further investigation.  相似文献   
7.
8.
Hepatic encephalopathy can be a life-threatening complication of fulminant hepatic failure. By understanding the pathophysiology involved in the induction of this neuropsychiatric disorder, future therapeutic and/or preventive attempts could be considered. In this study, an attempt has been made in order to shed more light on the mechanisms involved in the effects of thioacetamide (TAA)-induced fulminant hepatic encephalopathy on: (a) the adult rat brain total antioxidant status (TAS) and (b) the activities of acetylcholinesterase (AChE), (Na(+),K(+))-ATPase and Mg(2+)-ATPase. Moreover, in vitro experiments were conducted in order to evaluate the possible role of ammonia (incubated as NH(4)Cl, in a toxic concentration of 3mM) in the observed effects of TAA-induced fulminant hepatic encephalopathy on the examined adult rat brain enzyme activities. Fulminant hepatic encephalopathy caused a significant decrease in TAS (-22%, p < 0.001) and the activity of Na(+),K(+)-ATPase (-26%, p < 0.001), but had non-significant effects on the whole brain AChE and Mg(2+)-ATPase activities. The in vitro experiments (conducted through a 3h incubation with ammonia), showed no significant alterations in any of the examined parameters. Our in vitro and in vivo findings suggest that alterations in AChE and Mg(2+)-ATPase activities are not involved in the pathophysiology of the adult-onset fulminant hepatic encephalopathy, while the observed Na(+),K(+)-ATPase inhibition could be a result of the oxidative stress, neurotransmission deregulation, and/or of the presence of other toxic substances (that appear to act as direct or indirect inhibitors of the enzyme) and not due to the excess accumulation of ammonia in the brain.  相似文献   
9.
Synchronous malignancies in a pleural effusion are rare. A case of concurrent pleural infiltration by adenocarcinoma of unknown primary site and chronic lymphocytic leukemia (CLL) is presented in this case study, which was diagnosed by effusion cytology. Pleural effusion is not an uncommon complication in patients with B‐CLL. Even in a pleural effusion rich in monoclonal lymphocytes, the presence of a second cancer must be excluded because this can be the main cause of mortality. The role of cytology in such cases is of paramount importance. Diagn. Cytopathol. 2014;42:151–155. © 2012 Wiley Periodicals, Inc.  相似文献   
10.
The use of vaginal meshes has been an advance in the surgical management of women with pelvic organ prolapse. We reviewed the literature to synthesize the evidence regarding the infectious complications related to this new type of foreign body. We searched PubMed, current contents, and references of initially identified relevant articles and extracted data regarding the incidence, clinical manifestation, and management of vaginal mesh-related infections. The incidence of mesh-related infections and erosion ranged from 0 to 8%, and 0 to 33%, respectively, in the published studies. Various factors influence the development of vaginal mesh-related infectious complications such as the kind of biomedical material (e.g. filament structure, pore size) of the mesh, the type of procedure, the preventive measures taken, and the age and underlying comorbidity of the treated women. Non-specific pelvic pain, persistent vaginal discharge or bleeding, dyspareunia, and urinary or faecal incontinence are the most common manifestation of vaginal mesh-related infection. Clinical examination may reveal induration of the vaginal incision, vaginal granulation tissue, draining sinus tracts, and prosthesis erosion or rejection. Various pathogens have been implicated, including Gram-positive and Gram-negative aerobic and anaerobic bacteria. The management of mesh-related infections in women who underwent pelvic organ reconstruction is combined surgical and medical treatment. Although the use of vaginal meshes has become a new effective method of pelvic organ prolapse surgery clinicians should be aware of the various post-operative complications, including mesh-related infections.  相似文献   
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