43 research outputs found

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    Multi-messenger Observations of a Binary Neutron Star Merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 {{s}} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of {40}-8+8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 {M}ȯ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 {{Mpc}}) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.</p

    Can a Score Accurately Predict Readmissions in Geriatric Patients with Congestive Heart Failure?

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    Background: Congestive heart failure (CHF) affects 5.7 million Americans, It is considered the main cause of readmissions in adult population, associated with 134,500 readmissions annually. The LACE index is a commonly used tool to identify patients at risk of readmission or death within 30 days after hospital discharge. Methods: This is a retrospective study, we analyzed Electronic Medical Records of geriatric patients admitted with discharged diag- nose of acute Congestive Heart Failure decompensation from January 2012 to December 2014; selected patients were followed up for the next 30 days to determine if they were readmitted due acute CHF decompensation. Patients with admission no related to acute decompensation of CHF were excluded. For each patient we collected data regarding age, sex, ethnicity, body mass index, reason for admission, comorbidities (DM, renal/liver disease, etc.). Results: 49 patients were enrolled in the study, with 33 patients readmitted within 30 days and 16 patients with no readmissions within 30 days. We found patients in the readmission group had higher mean age compared with those who were not readmitted (77 years vs 71 years, p-value 0.04). In both groups LACE index was found elevated, when comparing high risk patients vs no high risk patients using LACE index there was no statistically significance (OR 2.13 95%CI 0.12-36.0 p-value 0.6). Length of hospital staying on readmis- sion group was 5.6 days and in no readmission group 4.5 days (P-value 0.23). Emergency department visit on readmission group was 1.4 and in no readmission group 1.1 (P-value 0.46). There was no statistical difference in both groups regarding Gender, ischemic heart disease, systolic heart failure and BMI. Conclusion: In this single retrospective study, LACE index score did not accurately predicted readmission within 30 days in geriatric patients with CHF. Not statistically difference among low risk patient and high risk using LACE index in terms of readmission within 30 days was found. Predicting who will be re-hospitalized is difficult, and much is unexplained

    Atrial Fibrillation in Patients with Heart Failure: Current State and Future Directions

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    Heart failure affects nearly 26 million people worldwide. Patients with heart failure are frequently affected with atrial fibrillation, and the interrelation between these pathologies is complex. Atrial fibrillation shares the same risk factors as heart failure. Moreover, it is associated with a higher-risk baseline clinical status and higher mortality rates in patients with heart failure. The mechanisms by which atrial fibrillation occurs in a failing heart are incompletely understood, but animal studies suggest they differ from those that occur in a healthy heart. Data suggest that heart failure-induced atrial fibrosis and atrial ionic remodeling are the underlying abnormalities that facilitate atrial fibrillation. Therapeutic considerations for atrial fibrillation in patients with heart failure include risk factor modification and guideline-directed medical therapy, anticoagulation, rate control, and rhythm control. As recommended for atrial fibrillation in the non-failing heart, anticoagulation in patients with heart failure should be guided by a careful estimation of the risk of embolic events versus the risk of hemorrhagic episodes. The decision whether to target a rate-control or rhythm-control strategy is an evolving aspect of management. Currently, both approaches are good medical practice, but recent data suggest that rhythm control, particularly when achieved through catheter ablation, is associated with improved outcomes. A promising field of research is the application of neurohormonal modulation to prevent the creation of the structural substrate for atrial fibrillation in the failing heart

    Low Skeletal Muscle Mass Independently Predicts Mortality in Patients With Chronic Heart Failure after an Acute Hospitalization

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    BACKGROUND: Heart failure (HF) is a syndrome associated with exercise intolerance, and its symptoms are more common in patients with low skeletal muscle mass (SMM). Estimation of muscle mass can be cumbersome and unreliable, particularly in patients with varying body weight. The psoas muscle area (PMA) can be used as a surrogate of sarcopenia and has been associated with poor outcomes in other populations. OBJECTIVES: The aim of this study was to assess if sarcopenia is associated with the survival of patients with HF after an acute hospitalization. METHOD: We retrospectively studied a cohort of 160 patients with HF who had abdominopelvic computed tomography during an acute hospitalization. We obtained standardized measurements of their PMA and defined sarcopenia as the lowest gender-based tertile of the said area. The patients were followed until death or discontinuation of care. We used Kaplan-Meier estimates and Cox regression analysis to assess the relationship between sarcopenia and all-cause mortality. RESULTS: We found that the 52 patients with sarcopenia had 4.5 times the risk of all-cause mortality at 1 year compared to the rest of the cohort (CI 1.784-11.765; p = 0.0016) after adjusting for significant covariates. Stratification by age and sex revealed that this association could be limited to males and patients \u3c 75 years old. CONCLUSION: The PMA, used as a surrogate of low SMM, is independently associated with an increased risk of late mortality after an acute hospitalization in patients with HF

    Clinical Outcomes of Beta-Blocker Therapy in Cocaine-Associated Heart Failure

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    BACKGROUND: Cocaine is associated with deleterious effects in the heart, including HFrEF. Although beta-blockers are recommended for this condition in other populations, their use is discouraged in cocaine users due to the possibility of exacerbating cocaine-related cardiovascular complications. This study was designed to determine if patients with heart failure and a reduced ejection fraction (HFrEF) who continue to use cocaine have better outcomes when they receive beta-blocker therapy than when they do not. METHODS: We performed a retrospective analysis of 72 beta-blocker-naive patients with HFrEF and active cocaine use. Patients who were prescribed beta-blockers as part of their therapy were compared to those who were not, and clinical and structural outcomes were compared after 12months of treatment. RESULTS: When patients with HFrEF and active cocaine use received beta-blocker therapy, they were more likely to have an improvement in their New York Heart Association functional class (p=0.0106) and left ventricular ejection fraction (p=0.0031) than when they did not receive beta-antagonists. In addition, the risk of cocaine-related cardiovascular events (p=0.0086) and of heart failure hospitalizations (p=0.0383) was significantly lower in patients who received beta-blockade than those who did not. CONCLUSIONS: beta-Blocker therapy is associated with improvement in the exercise tolerance and the left ventricular ejection fraction in patients with HFrEF and active cocaine use. They are also associated with a lower incidence of cocaine-related cardiovascular events and HFrEF-related readmissions

    Brugada Phenocopy Induced by Recreational Drug Use

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    Recreational drugs are commonly abused in all age groups. Intoxication with these substances can induce silent but significant electrocardiographic signs which may lead to sudden death. In this case study, we present a 49-year-old male with no medical comorbidities who came to the emergency department requesting opioid detoxification. Toxicology screen was positive for cocaine, heroin, and cannabis. Initial electrocardiogram (EKG) showed features of a Brugada pattern in the right precordial leads, which resolved within one day into admission. This presentation is consistent with the recently recognized clinical entity known as Brugada phenocopy

    Relationship Between Pulmonary Hypertension and Outcomes Among Patients With Heart Failure With Reduced Ejection Fraction

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    Objectives: To identify predictors of pulmonary hypertension (PHT) and the predictive value of PHT for rehospitalization among patients with heart failure with reduced ejection fraction (HFrEF). Methods: A retrospective study of 351 hospitalized patients with heart failure (HF). Patients 18 years and above with HFrEF secondary to non-ischemic cardiomyopathy were reviewed. Patients with coronary artery disease, preserved ejection fraction and other secondary causes of PHT apart from HF were excluded. PHT as a predictor of 30-day and six-month re-admission was assessed as well as important possible predictors of PHT. Cox regression analysis, multiple linear regression as well as other statistical tools were employed as deemed appropriate. Results: Thirty-seven (37) and 99 patients were re-hospitalized within 30 days and 6 months after discharge for decompensated HF, respectively. After Cox regression analysis, higher hemoglobin reduced the odds of rehospitalization for decompensated HF (p = 0.015) within 30 days after discharge while higher pulmonary artery systolic pressure (PASP) (p = 0.002) and blood urea nitrogen (BUN) (p = 0.041) increased the odds of rehospitalization within 6 months of discharge. The predictors of the PHT among patients with HFrEF after multiple linear regression were low BMI (p = 0.027), increasing age (p = 0.006) and increased left atrial diameter (LAD) on echocardiography (p = 0.0001). Conclusion: Patients with HFrEF have a high predisposition to developing PHT if at admission, they have low BMI, dilated left atrium or are older. Patients with one or more of these attributes may need more intensive therapy to reduce the risk of developing PHT and in turn reduce readmission rates
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