4 research outputs found
Development of A Method for Estimating the Effect of Transformation of the Normalized Frequency Mismatch Function of A Coherent Bundle of Radio Pulses on the Quality of Radar Frequency Resolution
The necessity of studying the influence of the transformation of the frequency mismatch function of a coherent bundle of radio pulses on the quality of solving the radar frequency resolution problem is substantiated. This solution determines the effectiveness of radar observation of high-speed and maneuvering individual and group aerodynamic objects. The method is based on explicit expressions for calculating the normalized frequency mismatch function of a coherent bundle of radio pulses, taking into account its transformation due to the radial motion of high-speed and maneuvering individual and group aerodynamic objects. The estimation of the potential frequency resolution of bundles with different numbers of radio pulses with typical parameters for a coherent pulse radar is carried out. Possible values of frequency resolution under the additive effect of uncorrelated internal noise of the radar receiver and the multiplicative effect of correlated phase fluctuations of the radar signal are estimated. With an insignificant multiplicative effect of correlated phase fluctuations, a twofold increase in the number of radio pulses in a bundle provides an improvement in the frequency resolution (reduction of the width of the normalized frequency mismatch function) by 100 %. With the predominant multiplicative effect of these fluctuations, a twofold increase in the number of radio pulses results in an improvement in the frequency resolution by about 40 %. The developed method is of great theoretical and practical importance for the further development of the radar theory of high-speed and maneuvering individual and group aerodynamic objects
Hypertensive disorders in women with peripartum cardiomyopathy: insights from the ESC EORP PPCM Registry
Aims:
Hypertensive disorders occur in women with peripartum cardiomyopathy (PPCM). How often hypertensive disorders co-exist, and to what extent they impact outcomes, is less clear. We describe differences in phenotype and outcomes in women with PPCM with and without hypertensive disorders during pregnancy.
Methods:
The European Society of Cardiology PPCM Registry enrolled women with PPCM from 2012-2018. Three groups were examined: 1) women without hypertension (âPPCM-noHTNâ); 2) women with hypertension but without pre-eclampsia (âPPCM-HTNâ); 3) women with pre-eclampsia (âPPCM-PEâ). Maternal (6-month) and neonatal outcomes were compared.
Results:
Of 735 women included, 452 (61.5%) had PPCM-noHTN, 99 (13.5%) had PPCM-HTN and 184 (25.0%) had PPCM-PE. Compared to women with PPCM-noHTN, women with PPCM-PE had more severe symptoms (NYHA IV in 44.4% and 29.9%, p<0.001), more frequent signs of heart failure (pulmonary rales in 70.7% and 55.4%, p=0.002), higher baseline LVEF (32.7% and 30.7%, p=0.005) and smaller left ventricular end diastolic diameter (57.4mm [±6.7] and 59.8mm [±8.1], p<0.001). There were no differences in the frequencies of death from any cause, re-hospitalization for any cause, stroke, or thromboembolic events. Compared to women with PPCM-noHTN, women with PPCM-PE had a greater likelihood of left ventricular recovery (LVEFâ„50%) (adjusted OR 2.08 95% CI 1.21-3.57) and an adverse neonatal outcome (composite of termination, miscarriage, low birth weight or neonatal death) (adjusted OR 2.84 95% CI 1.66-4.87).
Conclusion:
Differences exist in phenotype, recovery of cardiac function and neonatal outcomes according to hypertensive status in women with PPCM
Global variations in heart failure etiology, management, and outcomes
Importance: Most epidemiological studies of heart failure (HF) have been conducted in high-income countries with limited comparable data from middle- or low-income countries.
Objective: To examine differences in HF etiology, treatment, and outcomes between groups of countries at different levels of economic development.
Design, Setting, and Participants: Multinational HF registry of 23âŻ341 participants in 40 high-income, upperâmiddle-income, lowerâmiddle-income, and low-income countries, followed up for a median period of 2.0 years.
Main Outcomes and Measures: HF cause, HF medication use, hospitalization, and death.
Results: Mean (SD) age of participants was 63.1 (14.9) years, and 9119 (39.1%) were female. The most common cause of HF was ischemic heart disease (38.1%) followed by hypertension (20.2%). The proportion of participants with HF with reduced ejection fraction taking the combination of a ÎČ-blocker, renin-angiotensin system inhibitor, and mineralocorticoid receptor antagonist was highest in upperâmiddle-income (61.9%) and high-income countries (51.1%), and it was lowest in low-income (45.7%) and lowerâmiddle-income countries (39.5%) (Pâ<â.001). The age- and sex- standardized mortality rate per 100 person-years was lowest in high-income countries (7.8 [95% CI, 7.5-8.2]), 9.3 (95% CI, 8.8-9.9) in upperâmiddle-income countries, 15.7 (95% CI, 15.0-16.4) in lowerâmiddle-income countries, and it was highest in low-income countries (19.1 [95% CI, 17.6-20.7]). Hospitalization rates were more frequent than death rates in high-income countries (ratioâ=â3.8) and in upperâmiddle-income countries (ratioâ=â2.4), similar in lowerâmiddle-income countries (ratioâ=â1.1), and less frequent in low-income countries (ratioâ=â0.6). The 30-day case-fatality rate after first hospital admission was lowest in high-income countries (6.7%), followed by upperâmiddle-income countries (9.7%), then lowerâmiddle-income countries (21.1%), and highest in low-income countries (31.6%). The proportional risk of death within 30 days of a first hospital admission was 3- to 5-fold higher in lowerâmiddle-income countries and low-income countries compared with high-income countries after adjusting for patient characteristics and use of long-term HF therapies.
Conclusions and Relevance: This study of HF patients from 40 different countries and derived from 4 different economic levels demonstrated differences in HF etiologies, management, and outcomes. These data may be useful in planning approaches to improve HF prevention and treatment globally