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To assess the accuracy of quantitative analysis of global and regional wall motion and wall thickening of the left ventricle with cine magnetic resonance (MR), images obtained in eight pigs before and after myocardial infarction were compared with those obtained using gadolinium diethylenetriaminepen-taacetic acid (Gd-DTPA)-enhanced multislice spin-echo MR imaging and determination of pathology. The region with abnormal wall motion and wall thickening, as determined with cine MR imaging, identified the same region of infarction as indicated by Gd-DTPA-enhanced spin-echo MR imaging and pathology. Within the infarcted region wall motion and wall thickening analyzed with the centerline method were significantly reduced. We conclude that the use of quantitative analysis of cine MR images accurately determines localization and extent of regional left ventricular dysfunction in the infarcted heart in vivo. This analysis using dedicated software including the centerline method allows sequential assessment of regional left ventricular function in normal and infarcted hearts.  相似文献   
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Goal of this study was to compare the quantitative coronary arteriographic (QCA) results obtained with the Philips DCI/ACA analytical software package with those from postmortem casts in an animal experimental setting. Standard digital coronary arteriograms were obtained from 6 mongrel dogs. After the imaging procedure, the dogs were sacrificed and casts were made of the coronary trees by filling the vessels with a mixture of radio-opaque barium and silicone gel at a fixed pressure of 100 mmHg. Vessel diameters were measured from the digital arteriograms at a total of 118 selected locations with the ACA package. Thin slices were cut from the casts at these same measurement locations and the areas of the cross sections were obtained by manual tracing of the outline of each slice in an approximately 40 × magnified image. From these cross-sectional areas, cast diameters were derived using the formula for circular cross-sections. Cast diameters ranged in size from 0.69 to 3.30 mm. The systematic error between the measurements was found to be 0.058 mm; (p < 0.015) and the standard deviation of the signed difference 0.255 mm; the correlation coefficient was r = 0.91. The largest error sources are supposed to be the slight differences in the selection of identical positions in the X-ray images and on the casts, and the ‘out-of-plane’ magnification for a number of vessel locations. This postmortem study demonstrates that the diameters of coronary vessels can be measured from digital arteriograms with the DCI/ACA package with a high degree of accuracy and precision.  相似文献   
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OBJECTIVE: To determine the extent to which chronic illness and disease severity affect patient satisfaction with their primary care provider in general internal medicine clinics. DESIGN: Cross-sectional mailed questionnaire study. SETTING: Primary care clinics at 7 Veterans Affairs medical centers. PATIENTS/PARTICIPANTS: Of 62,487 patients participating in the Ambulatory Care Quality Improvement Project, 35,383 (57%) returned an initial screening questionnaire and were subsequently sent a satisfaction questionnaire. Patients (N=21,689; 61%) who returned the Seattle Outpatient Satisfaction Survey (SOSQ) were included in the final analysis, representing 34% of the original sample. MEASUREMENTS AND MAIN RESULTS: The organizational score of the SOSQ measures satisfaction with health care services in the internal medicine clinic, and the humanistic scale measures patient satisfaction with the communication skills and humanistic qualities of the primary care physician. For ischemic heart disease (IHD), chronic obstructive pulmonary disease (COPD), and diabetes, patient ability to cope with their disease was more strongly associated with patient satisfaction than disease severity. Among IHD patients, improvement in ability to cope emotionally with their angina was associated with higher SOSQ organizational scores (standardized beta=0.18; P<.001) but self-reported physical limitation due to angina was not (beta=0.01; P=.65). Similarly, in COPD, improved ability to cope with dyspnea was associated with greater organizational scores (beta=0.11; P<.001) but physical function was not (beta=-0.03; P=.27). For diabetes, increased education was associated with improved organizational scores (beta=0.31; P<.001) but improvement in symptom burden was not (beta=0.03; P=.14). Similar results were seen with prediction of SOSQ humanistic scores. CONCLUSIONS: Patient education and ability to cope with chronic conditions are more strongly associated with satisfaction with their primary care provider than disease severity. Further improvements in patient education and self-management may lead to improved satisfaction and quality of care.  相似文献   
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Side branches in the atherosclerotic lesion region are important as they highly influence the treatment strategy selection and optimization. Moreover, they are reliable landmarks for image registration. By providing high resolution delineation of coronary morphology, intravascular optical coherence tomography (IVOCT) has been increasingly used for side branch analysis. This paper presents a fully automated method to detect side branches in IVOCT images, which relies on precise segmentation of the imaging catheter, the protective sheath, the guide wire and the lumen. 25 in-vivo data sets were used for validation. The intraclass correlation coefficient between the algorithmic results and manual delineations for the imaging catheter, the protective sheath and the lumen contour positions was 0.997, 0.949 and 0.974, respectively. All the guide wires were detected correctly and the Dice’s coefficient of the shadow regions behind the guide wire was 0.97. 94.0% of 82 side branches were detected with 5.0% false positives and the Dice’s coefficient of the side branch size was 0.85. In conclusion, the presented method has been demonstrated to be accurate and robust for side branch analysis.OCIS codes: (100.6950) Tomographic image processing, (110.4500) Optical coherence tomography  相似文献   
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The previously study found, using a mouse model, that acute myocardial infarction accelerated atherosclerosis. This study assessed whether ST elevation myocardial infarction (STEMI) accelerates the progression of non-culprit coronary lesion (NCCL) in patients who underwent percutaneous coronary interventions (PCI). Four hundred and forty-nine patients who underwent successful PCI with stents and follow-up coronary angiography in a single center were enrolled. The NCCL progression was assessed using three-dimensional quantitative coronary angiography and was defined as ≥10 % diameter reduction of a preexisting stenosis ≥50, ≥30 % diameter reduction of a stenosis <50 %, development of a new stenosis ≥30 % in a previously normal segment, or progression to total occlusion. The patients were classified into two groups according to whether the progression existed or not. The median age of patients was 58.4 years. The mean angiographic follow-up period was 12.3 months, 134 (29.8 %) patients had NCCL progression. Multivariate Cox regression analysis (step-wise) showed that STEMI was the only independent determinant of NCCL progression. Compared to the other coronary artery disease group, the crude hazard ratio (HR) of NCCL progression for the STEMI group was 3.20 (95 % CI 2.27–4.50; p < 0.001), and the association remained significantly after adjustment for age, sex, BMI, SBP, DBP, serum lipids, fasting blood glucose, peak monocyte count, smoking, drinking, hypertension, diabetes mellitus and lesion characteristics of NCCL (adjusted HR 3.56, 95 % CI 2.41–5.27; p < 0.001). The ST elevation acute myocardial infarction accelerates non-culprit coronary lesion atherosclerosis.  相似文献   
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