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991.
BackgroundIn obstructive sleep apnea (OSA), the upper airway is obstructed during sleep due to obesity and/or posterior collapse of the tongue root. Maxillofacial morphological abnormalities increase the risk of OSA in the Asian population. This study sought to elucidate whether three-dimensional (3D) photogrammetry measurements correlate with the severity of OSA irrespective of sex and degree of obesity.MethodsA prospective pilot study was performed, in which 37 consecutive adult patients (M/F = 28/9) underwent polysomnography and 3D photogrammetry in the supine position for the diagnosis of OSA. Measurements obtained from 3D photogrammetry included mandibular width (Mw), mandibular length (Ml), mandibular depth (Md), mandibular width–length angle (Mwla), and mandibular area (Ma). The effects of sex and body mass index (BMI) on the measurements and their association with the apnea–hypopnea index (AHI) were statistically analyzed. The inter-rater reliability of the measurements was evaluated using intraclass correlation coefficients (ICC).ResultsMwla (R = 0.73, p < 0.01), Mw (R = 0.39, p < 0.05), and Md (R = ?0.34, p < 0.05) were significantly correlated with the severity of OSA. On multivariate analysis, Mwla (p < 0.01) and Md (p < 0.05) remained independent factors for AHI after adjusting for sex, age, BMI, and neck circumference. In addition, diagnosability analysis revealed that Mwla was useful for identifying the presence of OSA (AHI ≥5) (cutoff: 78.6°, sensitivity: 0.938, specificity: 0.800, area under the curve: 0.931). The ICC was >0.9, showing high reliability.ConclusionsThis study suggests that Mwla measured using 3D photogrammetry can predict the presence of OSA and correlates with the severity of OSA, independent of obesity and sex.  相似文献   
992.
The purpose of this study was to determine the intracellular pH of the whole head and in voxels localized to the basal ganglia in patients with chronic liver disease using phosphorus-31 magnetic resonance spectroscopy (31P MRS). The study group compromised 82 patients with biopsy-proven cirrhosis (43 Child's grade A, 25 Child's grade B and 14 Child's grade C). Eleven subjects showed no evidence of neuropsychiatric impairment on clinical, psychometric and electrophysiological testing, 37 showed evidence of minimal hepatic encephalopathy and 34 had overt hepatic encephalopathy. Unlocalized31P MRS of the whole head was performed in 48 patients and 10 healthy volunteers. Localized31P MRS of the basal ganglia was performed in the 34 patients and in 20 healthy volunteers. The intracellular pH values were calculated from the chemical shift difference between the inorganic phosphate (Pi) and phosphocreatine (PCr) resonances. The percentage inorganic phosphate (%Pi), phosphocreatine (%PCr) and βNTP signals, relative to the total31P signal, and peak area ratios of inorganic phosphate and phosphocreatine, relative to βNTP were also measured. There were no differences between patients and volunteers in intracellular pH in31P MR spectra measured from the whole head or the basal ganglia. There was no correlation between the severity of encephalopathy (West Haven criteria) or liver dysfunction (Child score) and intracellular pH values. There was also no significant change in the inorganic phosphate, phosphocreatine or βNTP resonances in spectra acquired from the whole head. However, in spectra localized to the basal ganglia, there was a significant increase in mean Pi/NTP (p=0.02) and PCr/NTP (p=0.009). The mean %Pi and mean %PCr were also increased (p=0.06; p=0.05, respectively), but there was no significant change in mean %βNTP. When the patient population was classified according to the severity of encephalopathy, those with overt disease had a higher mean Pi/NTP and %Pi (p=0.03; p=0.01), compared to the reference population. Our results suggest that there are detectable bioenergetic abnormalities in patients with minimal hepatic encephalopathy or stable, overt chronic hepatic encephalopathy, but any associated intracellular pH change is probably a secondary, rather than a primary phenomenon.  相似文献   
993.
缺碘地区母婴分娩状态性别体重对新生儿TSH水平的影响   总被引:4,自引:1,他引:4  
为探讨缺碘地区母婴不同分娩状态及各种生理因素对新生儿促甲状腺激素(TSH)水平分布的影响,应用免疫放射分析(IRMA)测定了1579名新生儿脐带血TSH水平。结果发现,TSH值>5mU/L者所占百分数,城镇新生儿的为19.7%,农村的为25.9%(P<0.05),女婴的为28.1%,男婴的为21.4%(P<0.01),难产的为31.8%,足月顺产的为23.3%(P<0.05);TSH值≥20mU/L者所占百分数,早产的为5.3%,足月顺产的为0.4%(P<0.01),重度缺氧的为12.5%,正常的为0.4%(P<0.01)。提示不同地区、新生儿性别、母亲分娩状态及新生儿缺氧程度对新生儿TSH水平分布有一定影响。因此应用新生儿TSH评价人群中碘缺乏病流行状况时应当考虑这些因素  相似文献   
994.
《JACC: Cardiovascular Imaging》2019,12(12):2373-2385
ObjectivesThis study sought to compare the prognostic value of 2-dimensional (2D) right ventricular (RV) speckle tracking (STE) against cardiac magnetic resonance (CMR) RV ejection fraction (EF) and feature tracking (FT) and conventional echocardiographic parameters on overall and cardiovascular (CV) survival in patients with heart failure with reduced EF (HFrEF).BackgroundPrior works showed that RV systolic function predicts prognosis in HFrEF. 2D RVSTE had recently been proposed as new echocardiographic method to evaluate RV dysfunction.MethodsA total of 266 patients with HFrEF (mean LVEF 23 ± 7%, 60 ± 14 years of age; 29% women) underwent RV function assessment using CMR and 2D echocardiography and were followed for a primary endpoint of overall death and secondary endpoint of CV death.ResultsAverage CMR-RVEF was 42 ± 15%, average STE RV global longitudinal strain (STE-RVGLS) was −18.0 ± 4.9%, and average CMR-FT-RVGLS was −11.8 ± 4.3%. After a median follow-up of 4.7 years, 102 patients died, 84 of a CV cause. RVEF, FT-RVGLS, tricuspid annulus plane systolic excursion (TAPSE), fractional area change (FAC), and STE-RVGLS were significant univariate predictors of overall and cardiac death. In multivariate Cox regression, age, ischemic etiology, diabetes, New York Heart Association functional class III to IV, and beta-blocker treatment were independent clinical predictors of overall mortality. CMR-RVEF (chi-square to enter = 3.9; p < 0.05), FT-RVGLS (chi-square to enter 3.7; p = 0.05), FAC (chi-square to enter 6.2; p = 0.02), and TAPSE (chi-square to enter = 4.1; p = 0.04) provided additional prognostic value over these baseline parameters, but the additional predictive value of STE-RVGLS (chi-square to enter = 10.8; p < 0.001) was significantly (p < 0.05) higher than the other tests. Additional hazard ratio to predict overall mortality was 2.5 (95% confidence interval [CI]: 1.6 to 3.9) for STE-RVGLS <−19%, 2.15 (95% CI: 1.34 to 3.43) for TAPSE >15 mm, 1.6 (95% CI: 1.02 to 2.49) for FAC >39%, 1.93 (95% CI: 1.25 to 2.99) for RVEF >41%, and 1.87 (95% CI: 1.10 to 3.19) for CMR-FT-RVGLS <−15%.Conclusions2D RVGLS provides strong additional prognostic value to predict overall and CV mortality in HFrEF, with higher predictive value than CMR-RVEF, CMR-FT-RVGLS, TAPSE, or FAC. This supports use of STE-RVGLS to identify higher-risk HFrEF patients.  相似文献   
995.
《JACC: Cardiovascular Imaging》2019,12(12):2517-2537
Rheumatic diseases are immune-mediated inflammatory multisystem diseases with frequent cardiovascular manifestations including perimyocarditis, valvular disease, coronary artery disease, heart failure with or without preserved ejection fraction, pulmonary hypertension, aneurysms, and thrombosis. Echocardiography, carotid ultrasonography, cardiac computed tomography, cardiac magnetic resonance imaging, and positron emission tomography are valid diagnostic tools for the detection of the cardiovascular complications of the multisystem diseases that frequently determine prognosis. Furthermore, the findings of these methods may offer additive risk stratification in asymptomatic patients over the conventional risk scores used to assess cardiovascular risk in the primary prevention setting. Finally, the imaging methods offer a unique opportunity to monitor the effects of treatment on atherosclerotic lesions, coronary microcirculatory dysfunction, myocardial inflammation and fibrosis. However, studies are needed to investigate whether improvement of imaging markers by treatment or selection of treatment according to its effects on surrogate imaging markers is linked to improved prognosis.  相似文献   
996.
The MESA (Multi-Ethnic Study of Atherosclerosis) is a National Heart, Lung, and Blood Institute–sponsored prospective study aimed at studying the prevalence, progression, determinants, and prognostic significance of subclinical cardiovascular disease in a sex-balanced, multiethnic, community-dwelling U.S. cohort. MESA helped usher in an era of noninvasive evaluation of subclinical atherosclerosis presence, burden, and progression for the evaluation of atherosclerotic cardiovascular disease risk, beyond what could be predicted by traditional risk factors alone. Concepts developed in MESA have informed international patient care guidelines, providing new tools to effectively guide public health policy, population screening, and clinical decision-making. MESA is grounded in an open science model that continues to be a beacon for collaborative science. In this review, we detail the original goals of MESA, and describe how the scope of MESA has evolved over time. We highlight 10 significant MESA contributions to cardiovascular medicine, and chart the path forward for MESA in the year 2021 and beyond.  相似文献   
997.
Background: T1 mapping allows quantitative assessment of “diffuse” deposition of amyloid protein in the myocardium. Early detection of cardiac involvement and potential prognostic improvement could benefit patients with AL amyloidosis.

Objectives: This study aims to evaluate the regional variation of amyloid infiltration in the left ventricle and the prognostic value of T1 mapping in patients with AL amyloidosis.

Methods: We prospectively enrolled 77 patients with AL amyloidosis who underwent cardiac magnetic resonance on a 3.0-T scanner. Native T1 and extracellular volume (ECV) were quantitated on the basal, mid, and apical levels of the left ventricle. Late gadolinium enhancement (LGE) pattern (no or non-specific LGE, sub-endocardial LGE, and transmural LGE) was also assessed. Forty healthy subjects served as controls. The primary end point was all-cause mortality.

Results: Basal ECV (26.9?±?2.8% versus 31.1?±?4.9%, p?<?.001) were lower than apical ECV in the healthy controls; however, basal ECV (60.6?±?11.5% versus 53.0?±?9.6%, p?=?.003) were significantly higher than apical ECV in patients with transmural LGE. During the follow-up period (median duration, 28?months; 25th–75th percentile, 13.5–38.0?months), 46 patients died. Basal ECV has the largest area under the curve of 0.845 (95% CI, 0.747–0.917) to predict all-cause mortality. Multivariable Cox analysis indicated that basal ECV was an independent prognostic factor and showed incremental prognostic value beyond NYHA class, Mayo stage, and LGE pattern.

Conclusion: We demonstrated that T1 mapping may have the potential to detect a characteristic amyloid deposition with a decreasing gradient from base to apex. Furthermore, myocardial ECV indicated that basal amyloid infiltration provided robust and incremental prognostic value in patients with AL amyloidosis.  相似文献   

998.
《JACC: Cardiovascular Imaging》2020,13(12):2561-2572
ObjectivesThe aim of this study was to investigate the relationship between extracellular volume fraction (ECV), a noninvasive parameter that quantifies the degree of diffuse myocardial fibrosis on cardiac magnetic resonance (CMR), and left ventricular diastolic dysfunction (LVDD) in patients with aortic stenosis (AS).BackgroundMyocardial fibrosis on invasive myocardial biopsy is associated with LVDD. However, there is a paucity of data on the association between noninvasively quantified diffuse myocardial fibrosis and the degree of LVDD and how these are related to symptoms and long-term prognosis in patients with AS.MethodsPatients with moderate or severe AS (n = 191; mean age 68.4 years) and 30 control subjects without cardiovascular risk factors underwent CMR. LVDD grade was evaluated using echocardiography according to the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines. Clinical outcomes were defined as a composite of all-cause mortality or hospitalization for heart failure aggravation.ResultsPatients in higher ECV quintiles had a significantly higher prevalence of LVDD. Higher ECV was particularly associated with decreased myocardial relaxation (septal e′ <7 cm/s) and increased LV filling pressure (E/e′ ratio ≥15). Although both impaired diastolic function and higher ECV were significantly associated with a worse degree of dyspnea, patients with higher ECV showed greater dyspnea within the same grade of LVDD. During a median follow-up period of 5.6 years, 37 clinical events occurred. Increased ECV, as well as lower septal e′ and higher E/septal e′ ratio, were independent predictors of clinical events, irrespective of age, AS severity, aortic valve replacement, and left ventricular (LV) ejection fraction. ECV provided incremental prognostic value on top of clinical factors and LV systolic and diastolic function.ConclusionsDiffuse myocardial fibrosis, assessed using ECV on CMR, was associated with LVDD in patients with AS, but both ECV and LV diastolic function parameters provided a complementary explanation for dyspnea and clinical outcomes. Concomitant assessment of both LVDD and diffuse myocardial fibrosis may further identify patients with AS with greater symptoms and worse prognosis.  相似文献   
999.
BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has adversely affected diagnosis and treatment of noncommunicable diseases. Its effects on delivery of diagnostic care for cardiovascular disease, which remains the leading cause of death worldwide, have not been quantified.ObjectivesThe study sought to assess COVID-19’s impact on global cardiovascular diagnostic procedural volumes and safety practices.MethodsThe International Atomic Energy Agency conducted a worldwide survey assessing alterations in cardiovascular procedure volumes and safety practices resulting from COVID-19. Noninvasive and invasive cardiac testing volumes were obtained from participating sites for March and April 2020 and compared with those from March 2019. Availability of personal protective equipment and pandemic-related testing practice changes were ascertained.ResultsSurveys were submitted from 909 inpatient and outpatient centers performing cardiac diagnostic procedures, in 108 countries. Procedure volumes decreased 42% from March 2019 to March 2020, and 64% from March 2019 to April 2020. Transthoracic echocardiography decreased by 59%, transesophageal echocardiography 76%, and stress tests 78%, which varied between stress modalities. Coronary angiography (invasive or computed tomography) decreased 55% (p < 0.001 for each procedure). In multivariable regression, significantly greater reduction in procedures occurred for centers in countries with lower gross domestic product. Location in a low-income and lower–middle-income country was associated with an additional 22% reduction in cardiac procedures and less availability of personal protective equipment and telehealth.ConclusionsCOVID-19 was associated with a significant and abrupt reduction in cardiovascular diagnostic testing across the globe, especially affecting the world’s economically challenged. Further study of cardiovascular outcomes and COVID-19–related changes in care delivery is warranted.  相似文献   
1000.
A patient with a ruptured left ventricular pseudoaneurysm complicating an acute posteroinferior myocardial infarction is described. Left ventricular pseudoaneurysms are a rare complication of acute myocardial infarction, usually occurring with inferior and/or posterior infarction. In contrast to true aneurysms, pseudoaneurysms are much more likely to rupture, regardless of size, causing hemopericardium and death. Therefore, once the diagnosis has been confirmed, prompt surgical resection is the current accepted treatment. The most accurate noninvasive diagnostic method has been echocardiography, with recent reports suggesting improved diagnosis with color flow Doppler echocardiography. Ventriculography confirms the diagnosis with more accurate anatomic detail, but is an invasive procedure. In our patient, two-dimensional and color Doppler echocardiography could not demonstrate the suspected pseudoaneurysm, which was demonstrated by ventriculography. However, magnetic resonance imaging (MRI) demonstrated the pseudoaneurysm, showing detailed anatomy not obvious on ventriculography. Before surgery could be performed, the patient died and was autopsied. Heart sections corresponding to MRI planes confirmed the MRI findings. A review of the literature has revealed no similar reports using MRI in the diagnosis of postinfarction pseudoaneurysms. Major advantages of MRI are generation of three-dimensional soft tissue images noninvasively, and generation of tissue contrast by rapid imaging sequences, obviating the need for contrast injection. Major disadvantages of MRI are the high cost of instrumentation, nonportability, and a requirement for patient immobility during the study. In cases of suspected pseudoaneurysm with equivocal echocardiography findings, MRI could provide early diagnosis, leading to early surgical intervention and increased patient survival.  相似文献   
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