200 research outputs found
LOWER HOSPITAL VOLUME IS ASSOCIATED WITH HIGHER IN-HOSPITAL MORTALITY FOR PATIENTS UNDERGOING PRIMARY PCI FOR ST ELEVATION MYOCARDIAL INFARCTION
Percutaneous Coronary Intervention and Drug-Eluting Stent Use Among Patients ≥85 Years of Age in the United States
ObjectivesThis study assessed the comparative effectiveness of drug-eluting stents (DES) versus bare-metal stents (BMS) among patients ≥85 years of age.BackgroundDespite an aging population, little is known about the comparative effectiveness of DES versus BMS among patients age ≥85 years undergoing percutaneous coronary intervention (PCI).MethodsWe examined 471,006 PCI patients age ≥65 years at 947 hospitals in the National Cardiovascular Data Registry between 2004 and 2008 and linked to Medicare claims data. Long-term outcomes (median follow-up 640.8 ± 423.5 days) were compared between users of DES and BMS.ResultsPatients age ≥85 years comprise an increasing proportion of PCIs performed among elderly subjects, yet rates of DES use declined the most in this age group. Compared with BMS, use of DES was associated with lower mortality: age ≥85 years, 29% versus 38% (adjusted hazard ratio [HR]: 0.80 [95% confidence interval (CI): 0.77 to 0.83]); age 75 to 84 years, 17% versus 25% (HR: 0.77 [95% CI: 0.75 to 0.79]); and age 65 to 74 years, 10% versus 16% (HR: 0.73 [95% CI: 0.71 to 0.75]). However, the adjusted mortality difference narrowed with increasing age (pinteraction <0.001). In contrast, the adjusted HR for myocardial infarction rehospitalization associated with DES use was significantly lower with increasing age: age ≥85 years, 9% versus 12% (HR: 0.77 [95% CI: 0.71 to 0.83]); age 75 to 84 years, 7% versus 9% (HR: 0.81 [95% CI: 0.77 to 0.84]); and age 65 to 74 years, 7% versus 8% (HR: 0.84 [95% CI: 0.80 to 0.88]) (pinteraction <0.001).ConclusionsIn this national study of older patients undergoing PCI, declines in DES use were most pronounced among those aged ≥85 years, yet lower adverse-event rates associated with DES versus BMS use were observed
Comparative Effectiveness of Drug-Eluting Versus Bare-Metal Stents in Elderly Patients Undergoing Revascularization of Chronic Total Coronary Occlusions Results From the National Cardiovascular Data Registry, 2005–2008
ObjectivesThis study sought to investigate the long-term effectiveness of drug-eluting stents (DES) versus bare-metal stents (BMS).BackgroundImproved recanalization techniques have increased interest in percutaneous coronary intervention (PCI) for chronic total coronary occlusion (CTO). The long-term effectiveness of DES and BMS is not known.MethodsWe used data from 10,261 stable patients age ≥65 years at 889 U.S. hospitals who underwent CTO PCI from January 1, 2005, to December 31, 2008, in the NCDR (National Cardiovascular Data Registry) CathPCI Registry with linked Medicare inpatient claims for follow-up. Patient and procedural characteristics, and 30-month death, myocardial infarction, revascularization, and hospitalization for bleeding were evaluated by stent type. Outcomes following stenting were adjusted and compared using propensity score matching.ResultsDES were used for CTO PCI in 8,218 (80%) and BMS in 2,043 (20%). DES patients were younger (74.0 vs. 75.5 years, p < 0.001), had longer lesions (18.8 vs. 16.5 mm, p < 0.001), received more stents (≥2 stents in 45.7% vs. 37.9%, p < 0.001), and underwent multivessel PCI (18.9% vs. 15.1%, p < 0.001). DES implantation was associated with a lower hazard of mortality (hazard ratio [HR]: = 0.72, 95% confidence interval [CI]: 0.60 to 0.86, p < 0.001), a similar hazard for myocardial infarction (HR: 0.85, 95% CI: 0.61 to 1.19, p = 0.35), and subsequent revascularization (HR: 0.94, 95% CI: 0.79 to 1.12, p = 0.48), including PCI (HR: 0.98, 95% CI: 0.83 to 1.19, p = 0.87) and coronary artery bypass grafting (HR: 0.71, 95% CI: 0.46 to 1.10, p = 0.12). Hospitalization for bleeding was also similar for DES versus BMS (HR: 0.92; 95% CI: 0.61 to 1.39, p = 0.70).ConclusionsCompared with BMS, DES use in stable patients undergoing CTO PCI was associated with lower mortality, as well as similar myocardial infarction and repeat revascularization rates without an increase in subsequent bleeding requiring hospitalization
Inference on inspiral signals using LISA MLDC data
In this paper we describe a Bayesian inference framework for analysis of data
obtained by LISA. We set up a model for binary inspiral signals as defined for
the Mock LISA Data Challenge 1.2 (MLDC), and implemented a Markov chain Monte
Carlo (MCMC) algorithm to facilitate exploration and integration of the
posterior distribution over the 9-dimensional parameter space. Here we present
intermediate results showing how, using this method, information about the 9
parameters can be extracted from the data.Comment: Accepted for publication in Classical and Quantum Gravity, GWDAW-11
special issu
Use of mechanical circulatory support devices among patients with acute myocardial infarction complicated by cardiogenic shock
Importance: Mechanical circulatory support (MCS) devices, including intravascular microaxial left ventricular assist devices (LVADs) and intra-aortic balloon pumps (IABPs), are used in patients who undergo percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) complicated by cardiogenic shock despite limited evidence of their clinical benefit.
Objective: To examine trends in the use of MCS devices among patients who underwent PCI for AMI with cardiogenic shock, hospital-level use variation, and factors associated with use.
Design, Setting, and Participants: This cross-sectional study used the CathPCI and Chest Pain-MI Registries of the American College of Cardiology National Cardiovascular Data Registry. Patients who underwent PCI for AMI complicated by cardiogenic shock between October 1, 2015, and December 31, 2017, were identified from both registries. Data were analyzed from October 2018 to August 2020.
Exposures: Therapies to provide hemodynamic support were categorized as intravascular microaxial LVAD, IABP, TandemHeart, extracorporeal membrane oxygenation, LVAD, other devices, combined IABP and intravascular microaxial LVAD, combined IABP and other device (defined as TandemHeart, extracorporeal membrane oxygenation, LVAD, or another MCS device), or medical therapy only.
Main Outcomes and Measures: Use of MCS devices overall and specific MCS devices, including intravascular microaxial LVAD, at both patient and hospital levels and variables associated with use.
Results: Among the 28 304 patients included in the study, the mean (SD) age was 65.4 (12.6) years and 18 968 were men (67.0%). The overall MCS device use was constant from the fourth quarter of 2015 to the fourth quarter of 2017, although use of intravascular microaxial LVADs significantly increased (from 4.1% to 9.8%; P \u3c .001), whereas use of IABPs significantly decreased (from 34.8% to 30.0%; P \u3c .001). A significant hospital-level variation in MCS device use was found. The median (interquartile range [IQR]) proportion of patients who received MCS devices was 42% (30%-54%), and the median proportion of patients who received intravascular microaxial LVADs was 1% (0%-10%). In multivariable analyses, cardiac arrest at first medical contact or during hospitalization (odds ratio [OR], 1.82; 95% CI, 1.58-2.09) and severe left main and/or proximal left anterior descending coronary artery stenosis (OR, 1.36; 95% CI, 1.20-1.54) were patient characteristics that were associated with higher odds of receiving intravascular microaxial LVADs only compared with IABPs only.
Conclusions and Relevance: This study found that, among patients who underwent PCI for AMI complicated by cardiogenic shock, overall use of MCS devices was constant, and a 2.5-fold increase in intravascular microaxial LVAD use was found along with a corresponding decrease in IABP use and a significant hospital-level variation in MCS device use. These trends were observed despite limited clinical trial evidence of improved outcomes associated with device use
SYSTEMIC BUT NOT LOCAL BLEEDING IS ASSOCIATED WITH LONG-TERM MORTALITY IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION
Camouflaging in a Complex Environment—Octopuses Use Specific Features of Their Surroundings for Background Matching
Living under intense predation pressure, octopuses evolved an effective and impressive camouflaging ability that exploits features of their surroundings to enable them to “blend in.” To achieve such background matching, an animal may use general resemblance and reproduce characteristics of its entire surroundings, or it may imitate a specific object in its immediate environment. Using image analysis algorithms, we examined correlations between octopuses and their backgrounds. Field experiments show that when camouflaging, Octopus cyanea and O. vulgaris base their body patterns on selected features of nearby objects rather than attempting to match a large field of view. Such an approach enables the octopus to camouflage in partly occluded environments and to solve the problem of differences in appearance as a function of the viewing inclination of the observer
Predicting In-Hospital Mortality in Patients Undergoing Percutaneous Coronary Intervention
Background
Standardization of risk is critical in benchmarking and quality improvement efforts for percutaneous coronary interventions (PCI). In 2018, the CathPCI Registry was updated to include additional variables to better classify higher-risk patients.
Objectives
We sought to develop a model for predicting in-hospital mortality risk following PCI incorporating these additional variables.
Methods
Data from 706,263 PCIs performed between 7/2018-6/2019 at 1,608 sites were used to develop and validate a new full and pre-catheterization model to predict in-hospital mortality, and a simplified bedside risk score. The sample was randomly split into a development (70%, n=495,005) and validation cohort (30%, n=211,258). We created 1,000 bootstrapped samples of the development cohort and used stepwise selection logistic regression on each sample. The final model included variables that were selected in at least 70% of the bootstrapped samples and those identified a priori due to clinical relevance.
Results
In-hospital mortality following PCI varied based on clinical presentation. Procedural urgency, cardiovascular instability, and level of consciousness after cardiac arrest were most predictive of in-hospital mortality. The full model performed well, with excellent discrimination (c-index: 0.943) in the validation cohort and good calibration across different clinical and procedural risk cohorts. The median hospital risk-standardized mortality rate was 1.9% and ranged from 1.1% to 3.3% (interquartile range: 1.7%-2.1%).
Conclusions
The risk of mortality following PCI can be predicted in contemporary practice by incorporating variables that reflect clinical acuity. This model, which includes data previously not captured, is a valid instrument for risk stratification and for quality improvement efforts
The Effectiveness of Non-pyrethroid Insecticide-treated Durable Wall Lining to Control Malaria in Rural Tanzania: Study Protocol for a Two-armed Cluster Randomized Trial.
Despite considerable reductions in malaria achieved by scaling-up long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), maintaining sustained community protection remains operationally challenging. Increasing insecticide resistance also threatens to jeopardize the future of both strategies. Non-pyrethroid insecticide-treated wall lining (ITWL) may represent an alternate or complementary control method and a potential tool to manage insecticide resistance. To date no study has demonstrated whether ITWL can reduce malaria transmission nor provide additional protection beyond the current best practice of universal coverage (UC) of LLINs and prompt case management. A two-arm cluster randomized controlled trial will be conducted in rural Tanzania to assess whether non-pyrethroid ITWL and UC of LLINs provide added protection against malaria infection in children, compared to UC of LLINs alone. Stratified randomization based on malaria prevalence will be used to select 22 village clusters per arm. All 44 clusters will receive LLINs and half will also have ITWL installed on interior house walls. Study children, aged 6 months to 11 years old, will be enrolled from each cluster and followed monthly to estimate cumulative incidence of malaria parasitaemia (primary endpoint), time to first malaria episode and prevalence of anaemia before and after intervention. Entomological inoculation rate will be estimated using indoor CDC light traps and outdoor tent traps followed by detection of Anopheles gambiae species, sporozoite infection, insecticide resistance and blood meal source. ITWL bioefficacy and durability will be monitored using WHO cone bioassays and household surveys, respectively. Social and cultural factors influencing community and household ITWL acceptability will be explored through focus-group discussions and in-depth interviews. Cost-effectiveness, compared between study arms, will be estimated per malaria case averted. This protocol describes the large-scale evaluation of a novel vector control product, designed to overcome some of the known limitations of existing methods. If ITWL is proven to be effective and durable under field conditions, it may warrant consideration for programmatic implementation, particularly in areas with long transmission seasons and where pyrethroid-resistant vectors predominate. Trial findings will provide crucial information for policy makers in Tanzania and other malaria-endemic countries to guide resource allocations for future control efforts
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