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71.
We assessed patients' health-related quality of life after myocardial infarction and identified related variables. Clinical data were obtained retrospectively from medical records of consecutive patients admitted to a Midwestern university-affiliated medical center with diagnosis of myocardial infarction from July 1999-July 2000. Telephone interviews 7 months after discharge were made to administer the Short Form-12 (SF-12) and obtain patient, disease, drug, and intervention data. Complete information was obtained from 200 patients (mean age 63.4 +/- 13.1 yrs, 68% men). The mean Physical Component Summary (PCS)-12 score was 40.6 +/- 12.0, and the mean Mental Component Summary (MCS)-12 score was 52.1 +/- 10.0. Based on univariate analyses, low PCS-12 scores were associated with women; non-Q-wave infarctions; greater number of illnesses; history of myocardial infarction, chronic heart failure (CHF), transient ischemic attack (TIA), renal disease, peripheral vascular disease, or percutaneous coronary intervention (PCI); rehospitalization during the interim period; and unscheduled PCI since index myocardial infarction. Low MCS-12 scores were associated with age below 65 years, low overall self-reported drug therapy compliance, low self-reported compliance with angiotensin-converting enzyme inhibitor and lipid-lowering therapy, no history of coronary artery bypass graft, and no stress test since index myocardial infarction. A multivariate regression model for PCS-12 kept the following variables: greater number of illnesses, history of CHF or TIA, and rehospitalization since index myocardial infarction. The MCS-12 model contained age below 65 years, low overall compliance, and low compliance with lipid-lowering therapy. Further work is necessary to determine noncardiovascular predictors of quality of life and whether interventions for these patients will result in improved quality of life.  相似文献   
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BACKGROUND: Although increasing age has been associated with greater risk of mortality for patients undergoing mitral valve replacement, it is less clear whether this elevated risk is related to age-related differences in comorbidity or other clinical characteristics. METHODS: A population of 31,688 patients from The Society of Thoracic Surgeons National Cardiac Database undergoing mitral valve replacement either alone or in combination with coronary artery bypass grafting or tricuspid surgical procedures from 1997 to 2000 was examined to assess age-related variation in clinical features, morbidity, and mortality. Multivariable logistic regression was used to determine the effect of age after adjusting for other known risk factors. A classification tree was used to identify low-risk elderly (> or = 75 years) patients. RESULTS: Operative mortality increased four-fold from 4.1% in patients aged less than 50 years up to 17.0% in patients aged 80 years or more. Similarly, major operative complications (stroke, prolonged ventilation, reoperation for bleeding, renal failure, and sternal infection) also increased with age, rising from 13.5% (age < 50 years) to 35.5% (age > or = 80 years). Multivariable adjustment attenuated the odds of operative mortality, but age remained a significant risk factor. After adjusting for other patient risk factors, age accounted for 13% and 10% of the explainable risk for mortality and morbidity, respectively. Among the elderly, four variables (hemodynamic instability, New York Heart Association class IV, renal failure, and concomitant coronary artery bypass grafting) were identified to distinguish levels of risk, from operative mortality rates exceeding 31% to those with 7.7% mortality. CONCLUSIONS: Operative mortality and morbidity rise with increasing age of patients undergoing mitral valve replacement. Although this excess risk is partially a result of increased comorbid burden and other operative factors, age remains an independent powerful risk factor for operative risk for mitral valve replacement. Understanding the relationship of age with other risk factors for mitral valve replacement can help stratify risk, enabling physicians to identify lower risk patients.  相似文献   
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Context  Quality of care of patients with acute myocardial infarction (AMI) has received intense attention. However, it is unknown if a structured initiative for improving care of patients with AMI can be effectively implemented at a wide variety of hospitals. Objective  To measure the effects of a quality improvement project on adherence to evidence-based therapies for patients with AMI. Design and Setting  The Guidelines Applied in Practice (GAP) quality improvement project, which consisted of baseline measurement, implementation of improvement strategies, and remeasurement, in 10 acute-care hospitals in southeast Michigan. Patients  A random sample of Medicare and non-Medicare patients at baseline (July 1998–June 1999; n = 735) and following intervention (September 1–December 15, 2000; n = 914) admitted at the 10 study centers for treatment of confirmed AMI. A random sample of Medicare patients at baseline (January–December 1998; n = 513) and at remeasurement (March–August 2001; n = 388) admitted to 11 hospitals that volunteered, but were not selected, served as a control group. Intervention  The GAP project consisted of a kickoff presentation; creation of customized, guideline-oriented tools designed to facilitate adherence to key quality indicators; identification and assignment of local physician and nurse opinion leaders; grand rounds site visits; and premeasurement and postmeasurement of quality indicators. Main Outcome Measures  Differences in adherence to quality indicators (use of aspirin, -blockers, and angiotensin-converting enzyme [ACE] inhibitors at discharge; time to reperfusion; smoking cessation and diet counseling; and cholesterol assessment and treatment) in ideal patients, compared between baseline and postintervention samples and among Medicare patients in GAP hospitals and the control group. Results  Increases in adherence to key treatments were seen in the administration of aspirin (81% vs 87%; P = .02) and -blockers (65% vs 74%; P = .04) on admission and use of aspirin (84% vs 92%; P = .002) and smoking cessation counseling (53% vs 65%; P = .02) at discharge. For most of the other indicators, nonsignificant but favorable trends toward improvement in adherence to treatment goals were observed. Compared with the control group, Medicare patients in GAP hospitals showed a significant increase in the use of aspirin at discharge (5% vs 10%; P<.001). Use of aspirin on admission, ACE inhibitors at discharge, and documentation of smoking cessation also showed a trend for greater improvement among GAP hospitals compared with control hospitals, although none of these were statistically significant. Evidence of tool use noted during chart review was associated with a very high level of adherence to most quality indicators. Conclusions  Implementation of guideline-based tools for AMI may facilitate quality improvement among a variety of institutions, patients, and caregivers. This initial project provides a foundation for future initiatives aimed at quality improvement.   相似文献   
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The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
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Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.  相似文献   
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