George Ruiz

Data-Driven Decisions for Reducing Readmissions for Heart Failure: General Methodology and Case Study

Background Several studies have focused on stratifying patients according to their level of readmission risk, fueled in part by incentive programs in the U.S. that link readmission rates to the annual payment update by Medicare. Patient-specific predictions about readmission have not seen widespread use because of their limited accuracy and questions about the efficacy of using measures of risk to guide clinical decisions. We construct a predictive model for readmissions for congestive heart failure (CHF) and study how its predictions can be used to perform patient-specific interventions. We assess the cost-effectiveness of a methodology that combines prediction and decision making to allocate interventions. The results highlight the importance of combining predictions with decision analysis. Methods We construct a statistical classifier from a retrospective database of 793 hospital visits for heart failure that predicts the likelihood that patients will be rehospitalized within 30 days of discharge. We introduce a decision analysis that uses the predictions to guide decisions about post-discharge interventions. We perform a cost-effectiveness analysis of 379 additional hospital visits that were not included in either the formulation of the classifiers or the decision analysis. We report the performance of the methodology and show the overall expected value of employing a real-time decision system. Findings For the cohort studied, readmissions are associated with a mean cost of

Hospital readmission in heart failure, a novel analysis of a longstanding problem

13,679 with a standard error of

Isolation, Culture, and Identification of Amniotic Fluid-Derived Mesenchymal Stem Cells

1,214. Given a post-discharge plan that costs

Impaired exercise capacity following atrial septal defect closure: an invasive study of the right heart and pulmonary circulation

1,300 and that reduces 30-day rehospitalizations by 35%, use of the proposed methods would provide an 18.2% reduction in rehospitalizations and save 3.8% of costs. Conclusions Classifiers learned automatically from patient data can be joined with decision analysis to guide the allocation of post-discharge support to CHF patients. Such analyses are especially valuable in the common situation where it is not economically feasible to provide programs to all patients.

The expression and significance of proto-oncogene c-fos in viral myocarditis

Acute decompensated heart failure is a significant source of morbidity and mortality in the USA. It is the most common reason for admission in the Medicare population and the greatest cause of hospital readmission in both medical and surgical patients. As many of these readmissions are considered preventable, providers and hospital systems are seeking novel strategies to reduce rehospitalization. Several specific interventions have been shown to decrease readmission for heart failure. However, these are typically narrow in scope, focusing on one aspect of patient care and providing a one-size-fits-all approach. We review the data and propose integrating some of these interventions into a comprehensive patient-centered model that is organized into six categories: quality of medical management, early reassessment, health literacy, neuropsychological status, financial means and functional status. By screening for deficiencies in each of these categories, providers and hospital systems can use resources more efficiently to make targeted interventions to improve health outcomes and mitigate readmissions.

Role of the JAK/STAT signaling pathway in the pathogenesis of acute myocardial infarction in rats and its effect on NF-κB expression

Amniotic fluid-derived mesenchymal stem cells (AF-MSC) are newly described, excellent seed cells that have good differentiation capability and are convenient to obtain. However, it is important to develop a method to isolate and culture AF-MSC efficiently. Amniotic fluid samples were obtained from rabbits and the adherence method was used for AF-MSC culture. Flow cytometry, western blot, and immunofluorescence studies were used to analyze the phenotypic characteristics of the cultured AF-MSC. Amniotic fluid-derived mesenchymal stem cells were successfully isolated and cultured from amniotic fluid. Flow cytometric analysis demonstrated that these cells expressed CD29 and CD44, while they did not express CD34. The expression of transcription factor Oct-4 was confirmed by western blot and immunofluorescence analysis. Using the adherence method, we developed a successful, reproducible protocol for the isolation of AF-MSC from amniotic fluid. The results of our phenotypic analysis revealed that the AF-MSC isolated in the present study were multipotent cells.

The Effect of c-fos on Acute Myocardial Infarction and the Significance of Metoprolol Intervention in a Rat Model

Patients with early repair of an isolated atrial septal defect (ASD) are expected to have unremarkable right ventricular (RV) and pulmonary circulation physiology. Some studies, however, suggest persistent functional impairment. We aimed to examine the role of abnormal RV and pulmonary vascular response to exercise in patients who had undergone ASD closure. Using a previously published data set, we reviewed invasive exercise cardiopulmonary testing with right-sided hemodynamic data for 12 asymptomatic patients who had undergone ASD closure. The 5 (42%) patients with impaired maximal oxygen uptake ( V ̇ o2max) were older and exhibited a lower peak cardiac index (5.6 ± 0.8 vs. 9.0 ± 1.2 L/min/m 2 ; P = .005) because of abnormal stroke volume augmentation (+3.2 ± 3.9 vs. +17.4 ± 10.2 mL/m 2 ; P = .02). While all resting hemodynamic variables were similar, patients with low V ̇ o2max tended to have abnormal total pulmonary vascular resistance change during exercise (+11% ± 41% vs. ?28% ± 26%; P = .06) and had a steeper relation between mean pulmonary arterial pressure and cardiac index (5.8 ± 0.6 vs. 2.2 ± 0.1 L/min/m 2 ; P = .02). The increase in peak mean RV power during exercise was also significantly lower in the impaired- V ̇ o2max patients (4.7 ± 1.6 vs. 7.6 ± 2.1 J/s; P = .04). As described in the original study, despite normal resting hemodynamics, a subset of asymptomatic patients with repaired ASD had diminished exercise capacity. Our analysis allows us to conclude that this is due to a combination of abnormal pulmonary vascular response to exercise and impaired RV function.

Intravenous Epoprostenol for Management of Pulmonary Arterial Hypertension during Pregnancy

Backgroundc-fos may play a role in the pathogenesis of some diseases. The expression and function of c-fos in viral myocarditis (VMC) have not yet been reported. To study the change and significance of proto-oncogene c-fos in VMC is the objective of this experiment.MethodsAn animal model of VMC was established via coxsackie virus B3 inoculation. VMC mice were then treated with a c-fos monoclonal antibody and isoproterenol and the protein and mRNA expression of c-fos were studied via immunohistochemical analysis and in situ hybridization. Results were simultaneously analyzed for the significance of c-fos expression in mice with VMC.ResultsMyocardial necrosis and cell infiltration decreased after treatment with c-fos monoclonal antibody compared to control mice, while myocardial necrosis and cell infiltration were increased after treatment with isoproterenol. Positive cardiomyocytes with c-Fos expression increased at 3, 5, 7, 9, and 15 days after virus inoculation in VMC mice compared to control mice, while returning to almost normal levels at 35 days. The expression level of c-fos mRNA at 3 and 7 days after virus inoculation in VMC mice was also higher than that of control mice.Conclusionsc-fos expression in the cardiomyocytes of VMC mice is significantly increased, c-fos plays an important role in myocardial lesions. The apparent increase in expression of c-fos is likely to be involved in the pathogenesis of VMC.