Hypoadiponectinemia is associated with valvular inflammation and faster disease progression in patients with aortic stenosis.

OBJECTIVES: Adiponectin is a protein secreted by adipocytes which has anti-inflammatory properties. The objective of this study was to examine the relationship between adiponectinemia and the hemodynamic progression of aortic stenosis (AS) as well as the degree of inflammation in the valve explanted at the time of aortic valve replacement (AVR). METHODS: The plasma level of adiponectin was measured in 122 patients undergoing AVR. The explanted aortic valves were analyzed and the density of leukocytes (CD45+), T cells (CD3+) and blood vessels (von Willebrand factor positive; vWF+) was documented. Also, a subset of patients (n = 67) had ≥2 echocardiographic studies separated by at least 6 months, thereby allowing assessment of the rate of progression of stenosis during the preoperative period. RESULTS: Patients with lower plasma levels of adiponectin (<5.4 µg/ml) had a faster progression rate of the mean transvalvular gradient before surgery than those with higher levels (9 ± 1 vs. 4 ± 1 mm Hg/year; p = 0.008). Moreover, these patients with hypoadiponectinemia had significantly more leukocytes (CD45+), T cells and blood vessels (vWF+) in their explanted valves compared to those with higher adiponectin levels. CONCLUSION: These findings support the concept that adiponectin may play a protective role against the inflammatory process and progression of calcific AS.

Lipid-mediated inflammation and degeneration of bioprosthetic heart valves.

BACKGROUND: The durability of bioprosthetic valves is limited by structural valve degeneration (SVD) leading to bioprostheses (BPs) stenosis or regurgitation. We hypothesized that a lipid-mediated inflammatory mechanism is involved in the SVD of BPs. MATERIAL AND METHODS: Eighteen Freestyle stentless BP valves were explanted for SVD at a mean time of 5.9 +/- 3 years after implantation and were analysed by immunohistochemistry and transmission electron microscopy (TEM). RESULTS: The mean age of the patients was 65 +/- 8 years and there were 11 male and seven female patients. Two of the 18 BPs had macroscopic calcification, whereas the other valves had minimal or no macroscopic calcification. Tears at the commissures leading to regurgitation was present in 16 BPs. Immunohistochemistry showed the presence of oxidized low-density lipoprotein (ox-LDL) and glycosaminoglycans in the fibrosa layer of 13 BPs. Areas with ox-LDL were infiltrated by macrophages (CD68(+)) co-expressing the scavenger receptor CD36 and metalloproteinase-9 (MMP-9). Zymogram showed the active form of MMP-9 within explanted BPs. EM studies revealed the presence of lipid-laden cells featuring foam cells and fragmented collagen. Nonimplanted control BPs obtained from the manufacturer (n = 4) had no evidence of lipid accumulation, inflammatory cell infiltration or expression of MMP9 within the leaflets. CONCLUSIONS: These results support the concept that lipid-mediated inflammatory mechanisms may contribute to the SVD of BPs. These findings suggest that modification of atherosclerotic risk factors with the use of behavioural or pharmacological interventions could help to reduce the incidence of SVD.

Polyglycerophosphatide metabolism in Escherichia coli.

When Escherichia coli B cells were labelled with [14-C] glycerol and chased, there was a marked sparing of the phosphatidyl moiety compared to the nonacylated glycerol moiety of phosphatidylglycerol. When energy-depleted cells were restored to an energy-rich medium there resulted a conversion of 32-P-labelled cardiolipin to phosphatidylglycerol, a lack of phosphatidic acid accumulation and no loss in total polyglycerophosphatide counts. In cell-free extracts, phosphatidic acid produced from 32-P-labelled cardiolipin by the action of Escherichia coli phosphalipase D, was readily recycled to form poly-glycerophosphatide. In the presence of glycerol, such extracts displayed traansphosphatidylase activity by degrading cardiolipin to phosphatidyglycerol mainly. The results as a whole indicate that the enzyme synthesizing cardiolipin together with cardiolipin-hydrolyzing phospholipase D constitute a cycle which is normally involved in the turnover of polyglycerophosphatides in Escherichia coli.

Short-term treatment with mycophenolic acid and tacrolimus is tolerogenic for INS-1 cell clone transplantation and the deleterious effects of the drugs are limited: in vivo and in vitro studies.

One of the major requirements for a successful and life-lasting organ transplant is the access to safe, least toxic and permanent tolerance-inducing drugs. In this study we wished to evaluate the effects of tolerogenic doses of the immunosuppressive drugs mycophenolic acid (MPA) and tacrolimus (Tac) on clonal beta-cell lines, both in vivo and in vitro. Here we demonstrate that combined administration of low-dose MPA and Tac for 23 days induced permanent tolerance in an allogeneic beta-cell line transplant in Wistar rat liver through the portal vein. This short-term treatment of tolerogenic doses of the two drugs was deleterious to the survival of the transplanted cells but a small percentage of the cells could resist the effect and become fully active when the drugs were removed. The surviving cells, retrieved from growth in vivo, did not exhibit increased resistance in comparison to the original cells when tested in vitro at two glucose concentrations, 10 and 20 mM. The presence of a small percentage of resistant cells at the two glucose concentrations was also detected in the in vitro study after a continuous 8-day treatment demonstrating that the in vivo resistance was not related to micro-environmental protection but possibly to a phenotypic cell state that is yet to be determined.

Practices in the Prevention of Venous Thromboembolism.

Objective: The objective of this study was to determine the proportion of Massachusetts Medicare patients who received prophylaxis for venous thromboembolism following colectomy, hysterectomy, or total hip arthroplasty. Sample frame: All 90 Massachusetts acute care hospitals. Time frame: 1 April through 30 September, 1994. Target population: Patients discharged with an International Classification of Disease (ICD-9-CM) discharge diagnostic code (recorded in the Massachusetts Medicare Claims Database) for colectomy, hysterectomy, or total hip arthroplasty were used to identify the target patient population. Sample population: 1,397 patients randomly selected from the target population, including 467 total hip arthroplasties, 474 colectomies, and 456 hysterectomies. Data extraction: Medical records were reviewed by trained nurse abstractors who collected information on the use of prophylaxis for venous thromboembolism. Results: Prophylaxis for venous thromboembolism was employed by surgeons practicing in Massachusetts hospitals in 93% of total hip arthroplasty cases (regional variation 85-98%), 84% of colectomies (regional variation 57-93%), 66% of hysterectomies (regional variation 35-71%), and in 87% of the subset of 111 hysterectomies with malignancy (regional variation 25-100%). Conclusions: The results of this statewide study demonstrated significant regional and hospital-to-hospital variation in the use of prophylaxis for venous thromboembolism following major surgery. A lower rate of prophylaxis use was observed in hospitals with fewer than 200 beds and in hospitals that did not have teaching programs. Hospitals with below-average rates of prophylaxis were targeted for intensive quality improvement interventions.

Screening for HBsAg in pregnant women: a cost analysis of the universal screening policy in the province of Quebec.

We carried out a cost analysis of a universal prenatal screening policy for hepatitis B virus infection in pregnant women. A universal screening policy in the province of Quebec (87,000 births per year) would cost about $473,000 per year and the prevention of one chronic carrier, $8,915. The cost varied greatly according to the ethnic origin of the mother and the cost of the serologic test. Strategies to reduce the cost of the serologic test could greatly reduce the cost of this screening policy.

Transfusion-associated circulatory overload in orthopedic surgery patients: a multi-institutional study.

Although recognized as a serious complication of hemotherapy, few data are available on the incidence of transfusion-associated circulatory overload (TACO). Detailed demographic and clinical information was obtained from records of 382 Medicare patients undergoing total hip or knee replacements (and receiving transfusions) from January 1992 to December 1993 at five Massachusetts hospitals. Seventy-eight percent of the patients were women with a mean age of 77 years. Thirty-two percent had co-morbidities including myocardial or coronary disease. Transfusion-related complications and comorbidities were identified and reviewed by transfusion experts. Patients were excluded from consideration if non-transfusion factors such as myocardial disease could have contributed to the development of acute pulmonary edema. Four (3 females, 1 male) patients (1.05%) developed TACO postoperatively. Mean age of these patients was 84 years (range, 75-101) versus 77 years for non-TACO. The mean intraoperative estimated blood loss was 375 mL. Each patient received only 1-2 units of red blood cells prior to onset of TACO, and in two cases only autologous blood was used. The mean positive fluid balance was 2,480 mL. The mean pretransfusion hematocrit prior to circulatory overload (CO) was 26.0 percent. Symptoms were reversed with diuretics. Length of stay was significantly prolonged by these incidents. TACO is a frequent and serious event in an orthopedic surgical setting. It is associated with advanced age, increased health care costs, and may occur in the setting of modest transfusion volumes. The utilization of conservative transfusion criteria and fluid management in the perioperative setting may decrease the incidence of this complication in this population.

Improving the appropriateness of red blood cell transfusions in patients undergoing orthopedic surgery.

Orthopedic surgery is a common procedure among the elderly, and patients are at risk of receiving unnecessary blood transfusions. The goals of this project were to analyze current transfusion practices, identify opportunities for improvement, implement hospital-based quality improvement programs, and measure their impact on transfusion practices. Our aims were to decrease unnecessary transfusions and overall exposure to blood products. Data were abstracted from medical records, at baseline and postintervention. The results demonstrated significant improvements: a 55% decrease in avoidable transfusion events (from 42% to 19%, p < .001) and a decrease in the pre-transfusion hematocrit from a baseline of 29% to 26.9% in the postintervention period (p < .01). The percentage of single unit transfusion events increased from 71.9% to 77.2% (p = .05). These results suggest that the interventions had a significant impact on the use of blood. In the long term, these results should translate into cost savings and improved patient outcomes.

[Evaluation of quality of care in the United States]. / L'évaluation de la qualité des soins aux Etats-Unis.

Quality assessment in the USA has been undertaken during the past twenty years by different institutions sponsored by the Congress, the government and professional associations. The evaluation tools which were developed reflect both the diversity of the American medical scene fashions in health care management. They evolved from norms to incentives, but each step in this evolution left its marks in the form of regulations, financial incentives and traditions.

The prevention of venous thromboembolism: a statewide evaluation of practices in Massachusetts.

The objective of this study was to determine the proportion of Massachusetts Medicare patients who received prophylaxis for venous thromboembolism following colectomy, hysterectomy or total hip arthroplasty. The sample frame was all 90 Massachusetts acute care hospitals, and the time frame was 1 April to 30 September 1994. The patients discharged with an International Classification of Disease (ICD-9-CM) discharge diagnostic code (recorded in the Massachusetts Medicare Claims Database) for colectomy, hysterectomy or total hip arthroplasty were used to identify the target patient population. The sample population comprised 1397 patients randomly selected from the target population, including 467 total hip arthroplasties, 474 colectomies, and 456 hysterectomies. Medical records were reviewed by trained nurse abstractors who collected information on the use of prophylaxis for venous thromboembolism. Prophylaxis for venous thromboembolism was employed by surgeons practicing in Massachusetts hospitals in 93 per cent of total hip arthroplasty cases (regional variation 85-98 per cent), 84 per cent of colectomies (regional variation 57-93 per cent), 66 per cent of hysterectomies (regional variation 35-71 per cent), and in 87 per cent of the subset of 111 hysterectomies with malignancy (regional variation 25-100 per cent). The results of this statewide study demonstrated significant regional and hospital-to-hospital variation in use of prophylaxis for venous thromboembolism following major surgery. A lower rate of prophylaxis use was observed in hospitals with fewer than 200 beds and in hospitals that did not have teaching programmes. Hospitals with below-average rates of prophylaxis were targeted for intensive quality improvement interventions.

Physician practices in the prevention of deep vein thrombosis: the MassPRO DVT Study.

Numerous well-designed clinical trials have demonstrated that prophylaxis reduces the incidence of acute deep vein thrombosis (DVT) in high-risk surgical patients by two-thirds, with a corresponding reduction in mortality from pulmonary embolism. However, studies of clinical practices suggest that DVT prophylaxis is underused-for example, only 39% of high-risk surgical patients in 16 central Massachusetts hospitals were administered DVT prophylaxis in 1986. Subsequently, an intensive educational initiative was launched to improve utilization of DVT prophylaxis. Although some improvement was reported, the level of use was not optimal. The Massachusetts Peer Review Organization (MassPRO) DVT study was designed to gather data on recent practice patterns among Massachusetts surgeons and determine the need for additional educational and quality assurance efforts. The results indicate that there is broad compliance among orthopedic surgeons with consensus recommendations for the use of DVT prophylaxis. Nearly all patients who undergo total hip replacement in Massachusetts are protected from DVT by one or more methods of prophylaxis. These data suggest that the ongoing efforts to improve the use of DVT prophylaxis in Massachusetts since 1986 have come to fruition, at least with respect to total hip replacement.

Physician practices in the prevention of deep vein thrombosis: the masspro dvt study.

ABSTRACTNumerous well-designed clinical trials have demonstrated that prophylaxis reduces the incidence of acute deep vein thrombosis (DVT) in high-risk surgical patients by two-thirds, with a corresponding reduction in mortality from pulmonary embolism. However, studies of clinical practices suggest that DVT prophylaxis is underused - for example, only 39% of high-risk surgical patients in 16 central Massachusetts hospitals were administered DVT prophylaxis in 1986. Subsequently, an intensive educational initiative was launched to improve utilization of DVT prophylaxis. Although some improvement was reported, the level of use was not optimal. The Massachusetts Peer Review Organization (MassPRO) DVT study was designed to gather data on recent practice patterns among Massachusetts surgeons and determine the need for additional educational and quality assurance efforts. The results indicate that there is broad compliance among orthopedic surgeons with consensus recommendations for the use of DVT prophylaxis. Nearly all patients who undergo total hip replacement in Massachusetts are protected from DVT by one or more methods of prophylaxis. These data suggest that the ongoing efforts to improve the use of DVT prophylaxis in Massachusetts since 1986 have come to fruition, at least with respect to total hip replacement.

Red blood cell transfusion practices in patients undergoing orthopedic surgery: a multi-institutional analysis.

This retrospective review analyzed and compared transfusion practices in patients undergoing orthopedic surgery in five Massachusetts hospitals with current practice guidelines; opportunities for improvement were identified. Patient-specific clinical information and data about transfusion practices were obtained from the medical records of 384 Medicare patients undergoing orthopedic surgery between January 1992 and December 1993. The number of patients who donated autologous blood preoperatively differed significantly among hospitals as did the number of autologous units that were unused. The number of blood units transfused at each transfusion event also differed significantly; some surgeons transfused > or =2 units in the majority of their patients, while others transfused 1 unit at a time. This variation in practice was not explained by differences in patients' clinical status. The mean pretransfusion hematocrit was higher for autologous versus allogeneic blood, suggesting more liberal criteria to transfuse autologous blood. Nearly half of all transfusion events were determined to have been potentially avoidable. Avoidable transfusions were also three to seven times more likely with autologous than with allogeneic blood. Significant inter-hospital differences existed in the number of elective surgery patients exposed to allogeneic blood. The major determinant of allogeneic blood use in these patients was the availability of autologous blood. Each additional autologous blood unit available decreased the odds of allogeneic blood exposure twofold. Differences in intraoperative and postoperative blood salvage use also were noted. These findings indicate that significant variations in practice exist. Comparative data enabled hospitals to identify and target specific areas for improvement.

The Uniform Clinical Data Set: an evaluation of the proposed national database for Medicare's quality review program.

The accuracy, reliability, and validity of the Medicare Peer Review Organization (PRO) review process have all been questioned. Evidence concerning the PRO program's effect on cost and quality of care remains lacking. The Health Care Financing Administration has thus committed itself to reform, and the Uniform Clinical Data Set (UCDS) has been proposed as the national database for Medicare's quality review program. The UCDS is an automated, computerized data set designed to standardize the evaluation of quality. It should allow an objective, consistent, and efficient process for peer review, based on explicit decision criteria and on aggregated information about patterns of care and quality. But is this truly so? We review the existing evidence on the UCDS and compare it with the current PRO reviews of quality, concluding that although the UCDS can potentially improve the accuracy and the reliability of data abstraction and the validity of reviews, this remains to be shown. Preliminary data on the UCDS suggest that work is needed before it can meet appropriate expectations for a national database for quality assessments. We also propose a model for reviews of quality in which we show that reviews of care done in the context of internal quality improvement programs will differ in goals and intensity from reviews of care done at the national level. We suggest that the UCDS has a unique, but limited role--that of national surveillance of practice patterns. Detailed assessments of quality are more appropriately done at local or institutional levels.

[Malocclusion: dental or skeletal?]. / Malocclusion: dentaire ou squelettique?

This article presents a simple rapid and practical method, based both on clinical and radiographic examinations, which the dentist can use to the patient's advantage in differentiating dental from skeletal malocclusion.