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Objective Our objective was to determine a mechanism for the thrombocytopenia of murine Wiskott-Aldrich syndrome (WAS). Materials and Methods Consumption rates of WAS protein (WASP)(−) and wild-type (WT) platelets were measured by injection of 5-chloromethylfluorescein diacetate (CMFDA)-labeled platelets into WT or WASP(−) recipients, and by in vivo biotinylation. Platelet and reticulated platelet counts were performed using quantitative flow cytometry. Bone marrow megakaryocyte number and ploidy was assessed by flow cytometry. Phagocytosis of CMFDA-labeled, opsonized platelets was assessed using bone marrow–derived macrophages. Serum antiplatelet antibodies were assayed via their binding to WT platelets. Results CMFDA-labeled WASP(−) platelets are consumed more rapidly than WT platelets in either WT or WASP(−) recipients. In vivo biotinylation studies corroborate these findings and show a normal consumption rate for WASP(−) reticulated platelets. The number of reticulated platelets is reduced in WASP(−) mice, but a significant number of the mice show an increased proportion of reticulated platelets and more severe thrombocytopenia. Sera from some of the latter group contain antiplatelet antibodies. Compared to WT platelets, WASP(−) platelets opsonized with anti-CD61 or 6A6 antibody are taken up more rapidly by bone marrow–derived macrophages. In vivo consumption rates of WASP(−) platelets are more accelerated by opsonization than are those of WT platelets. Conclusion Both rapid clearance and impaired production contribute to the thrombocytopenia of murine WAS. Increased susceptibility of opsonized WASP(−) platelets to phagocytosis leads to increased in vivo clearance. This correlates with a higher incidence of individuals with an elevated fraction of reticulated platelets, a more severe thrombocytopenia, and antiplatelet antibodies.

Background The Angina With Extremely Serious Operative Mortality Evaluation (AWESOME) study was a multicenter Veterans Affairs randomized trial and registry that compared long-term survival of percutaneous coronary intervention with coronary artery bypass graft surgery for the treatment of patients with medically refractory myocardial ischemia and at least one additional risk factor for an adverse outcome with bypass. Both the randomized trial and the registry demonstrated comparable 3-year survival. The purpose of this study was to compare bypass and percutaneous intervention survival of AWESOME patients who were older than 70 years of age. Methods Over a 5-year period (1995 to 2000), 2,431 patients with medically refractory myocardial ischemia and at least one of the following five risk factors (prior heart surgery, myocardial infarction within 7 days, left ventricular ejection fraction less than 35%, age > 70 years, intraaortic balloon pump requirement to stabilize) were identified. Of these patients, 1,278 were older than 70 years of age. Eight hundred, seventy-one patients were turned down by at least one physician, 407 were acceptable to both physician and surgeon for randomization, and 236 (60%) consented to randomization. Of the 1,042 eligible patients who were not randomized, 871 had their revascularization directed by a physician who was not involved in the study. One hundred, seventy-one patients who were acceptable for randomization by both the interventional cardiologist and the cardiac surgeon refused consent. Results Bypass and percutaneous intervention survival were compared using Kaplan-Meier curves and log rank tests. Bypass and percutaneous intervention 36-month survival rates for patients older than 70 years of age were 76% and 75%, respectively, among the eligible patients. Survival was 71% and 78% among those patients who were randomized and 76% and 67% in the physician-directed subgroup. Of those patients who chose their revascularization techniques, the survivals were 79% and 85%, respectively. The survival differences are not large, and none of the global log rank tests of bypass compared with percutaneous intervention survival showed a statistically significant difference over 5 years. Conclusions Both the randomized and registry subgroups of patients who were older than 70 years of age support the trial conclusions that either bypass or percutaneous intervention effectively relieves medically refractory ischemia among high-risk unstable angina patients whose age was greater than 70 years.

OBJECTIVES This study compared survival after percutaneous coronary intervention (PCI) with survival after coronary artery bypass graft surgery (CABG) among diabetics in the Veterans Affairs AWESOME (Angina With Extremely Serious Operative Mortality Evaluation) study randomized trial and registry of high-risk patients. BACKGROUND Previous studies indicate that CABG may be superior to PCI for diabetics, but no comparisons have been made for diabetics at high risk for surgery. METHODS Over five years (1995 to 2000), 2,431 patients with medically refractory myocardial ischemia and at least one of five risk factors (prior CABG, myocardial infarction within seven days, left ventricular ejection fraction 70 years, or an intra-aortic balloon being required to stabilize) were identified. A total of 781 were acceptable for CABG and PCI, and 454 consented to be randomized. The 1,650 patients not acceptable for both CABG and PCI constitute the physician-directed registry, and the 327 who were acceptable but refused to be randomized constitute the patient-choice registry. Diabetes prevalence was 32% (144) among randomized patients, 27% (89) in the patient-choice registry, and 32% (525) in the physician-directed registry. The CABG and PCI survival rates were compared using Kaplan-Meier curves and log-rank tests. RESULTS The respective CABG and PCI 36-month survival rates for diabetic patients were 72% and 81% for randomized patients, 85% and 89% for patient-choice registry patients, and 73% and 71% for the physician-directed registry patients. None of the differences was statistically significant. CONCLUSIONS We conclude that PCI is a relatively safe alternative to CABG for diabetic patients with medically refractory unstable angina who are at high risk for CABG.

OBJECTIVES This study was designed to compare the three-year survival after percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG) in physician-directed and patient-choice registries with the Angina With Extremely Serious Operative Mortality Evaluation (AWESOME) randomized trial results. BACKGROUND The AWESOME multicenter randomized trial and registry compared the long-term survival after PCI and CABG for the treatment of patients with medically refractory myocardial ischemia and at least one additional risk factor for adverse outcome with CABG. The randomized trial demonstrated comparable three-year survival. METHODS Over a five-year period (1995 to 2000), 2,431 patients with medically refractory myocardial ischemia and at least one of five risk factors (prior heart surgery, myocardial infarction within seven days, left ventricular ejection fraction 70 years, intra-aortic balloon required to stabilize) were identified. By physician consensus, 1,650 patients formed a physician-directed registry assigned to CABG (692), PCI (651) or further medical therapy (307), and 781 were angiographically eligible for random allocation; 454 of these patients constitute the randomized trial, and the remaining 327 constitute a patient choice registry. Survival for CABG and PCI was compared using Kaplan-Meier curves and log-rank tests. RESULTS The CABG and PCI 36-month survival rates for randomized patients were 79% and 80%, respectively. The CABG and PCI 36-month survival rates were both 76% for the physician-directed subgroup; comparable survival rates for the patient-choice subgroup were 80% and 89%, respectively. None of the global log-rank tests for survival demonstrated significant differences. CONCLUSIONS Both registries support the randomized trial conclusion: PCI is an alternative to CABG for some medically refractory high-risk patients.

BACKGROUNDPercutaneous coronary intervention (PCI) and coronary artery bypass graft surgery (CABG) are being applied to high-risk populations, but previous randomized trials comparing revascularization methods have excluded a number of important high-risk groups.OBJECTIVESThis five-year, multicenter, randomized clinical trial was designed to compare long-term survival among patients with medically refractory myocardial ischemia and a high risk of adverse outcomes assigned to either a CABG or a PCI strategy, which could include stents.METHODSPatients from 16 Veterans Affairs Medical Centers were screened to identify myocardial ischemia refractory to medical management and the presence of one or more risk factors for adverse outcome with CABG, including prior open-heart surgery, age >70 years, left ventricular ejection fraction

This multicenter, prospective randomized trial was designed to test the hypotheses that percutaneous coronary intervention (PCI) is a safe and effective alternative to coronary artery bypass grafting (CABG) for patients with refractory ischemia and high risk of adverse outcomes. As a comparison of revascularization strategies, the trial specifically allows surgeons and interventionists to use new techniques as they become clinically available. After 42 months of this 72-month trial, 17,624 patients have been screened and 2022 met eligibility requirements: 341 have been randomized to either CABG or PCI, and the remaining 1681 are being prospectively followed in a registry. The 3-year overall survival of patients in the registry and randomized trial is comparable. To enhance accrual into the randomized trial, site visits were conducted, a few low-accruing hospitals were put on probation and/or replaced, eligibility criteria were reviewed at annual meetings of investigators, and the accrual period was extended by 1 year. These data demonstrate that a prospective randomized trial and registry of coronary revascularization for medically refractory high-risk patients is feasible.

Background We explored the role of dual time point fluorodeoxyglucose positron emission tomography/computed tomography (DTP PET/CT) scan in the differentiation of benign and malignant lung and mediastinal lesions. Methods We studied a sample of 72 consecutive patients who underwent DTP PET/CT scan for intrathoracic lesions. Information on demographics, initial and delayed maximum standardized uptake values (SUVmax) of lesions and final diagnosis were collected. Clinical criteria to diagnose benign lesions were defined as stability or regression of the lesion on follow-up after 2 years of initial detection. Sensitivity, specificity, predictive values and likelihood ratio and retention index were calculated using standard methods. Results Sixty-three (87%) patients had increased SUVmax in delayed scan (1 hour after initial scan). Among the patients with increased delayed uptake, 51 (80%) had malignant lesion and 12 (20%) had nonmalignant lesions. All 9 patients whose SUVmax decreased on delayed scan had nonmalignant lesions. The increased SUV on delayed scan was 100% sensitive in diagnosis of cancer but was only 42% specific. The positive predictive value was 80%, whereas the negative predictive value was 100%. Likelihood ratio for positive test was 1.75. Conclusions All the lesions with decreased SUVmax in delayed PET scan were nonmalignant. This was true for both lung and mediastinal lesions. This could be a very helpful diagnostic finding in areas with high prevalence of benign conditions such as histoplasmosis and sarcoidosis. Multiple invasive diagnostic modalities could be prevented in a significant percentage of patients, with attendant decrease in morbidity and health care costs.