Classification Model of Heart Transplant Outcomes Based on Features of Left Ventricular Functional Geometry

The function of the transplanted heart can be significantly affected by acute allograft rejection, chronic rejection, high blood pressure. These factors may induce cardiac remodelling with further adverse consequences for the patients. Dynamic change in the configuration of the left ventricle (LV) from end diastole to end systole (LV functional geometry) is an important factor of the heart pump function. The objective of this study is to evaluate the time dependent changes in parameters of LV functional geometry in the transplanted heart and to assess relations between the changes and adverse outcomes of the heart transplantation (HT). We used linear discriminant analysis (LDA) to build classification models based on either the standard echocardiographic parameters of LV systolic function and global longitudinal strain (GLS) or LV function geometry indexes. The training set for model building included data from patients with different degrees of systolic dysfunction. Using the models, we retrospectively classified data from 31 patients after orthotropic HT. In contrast to the LDA models based on the standard echocardiographic characteristics and GLS, the model based on the LV functional geometry data showed high accuracy in predicting allograft rejection and development of the heart failure in the HT patients. © 2018 Creative Commons Attribution

Derivation of a screening tool to identify patients with right ventricular dysfunction or tricuspid regurgitation after negative computerized tomographic pulmonary angiography of the chest

Many dyspneic patients who undergo computerized tomographic pulmonary angiography (CTPA) for presumed acute pulmonary embolism (PE) have no identified cause for their dyspnea yet have persistent symptoms, leading to more CTPA scanning. Right ventricular (RV) dysfunction or overload can signal treatable causes of dyspnea. We report the rate of isolated RV dysfunction or overload after negative CTPA and derive a clinical decision rule (CDR). We performed secondary analysis of a multicenter study of diagnostic accuracy for PE. Inclusion required persistent dyspnea and no PE. Echocardiography was ordered at clinician discretion. A characterization of isolated RV dysfunction or overload required normal left ventricular function and RV hypokinesis, or estimated RV systolic pressure of at least 40 mmHg. The CDR was derived from bivariate analysis of 97 candidate variables, followed by multivariate logistic regression. Of 647 patients, 431 had no PE and persistent dyspnea, and 184 (43%) of these 431 had echocardiography ordered. Of these, 64 patients (35% [95% confidence interval (CI): 28%-42%]) had isolated RV dysfunction or overload, and these patients were significantly more likely to have a repeat CTPA within 90 days (P = .02, [Formula: see text] test). From univariate analysis, 4 variables predicted isolated RV dysfunction: complete right bundle branch block, normal CTPA scan, active malignancy, and CTPA with infiltrate, the last negatively. Logistic regression found only normal CTPA scanning significant. The final rule (persistent dyspnea + normal CTPA scan) had a positive predictive value of 53% (95% CI: 37%-69%). We conclude that a simple CDR consisting of persistent dyspnea plus a normal CTPA scan predicts a high probability of isolated RV dysfunction or overload on echocardiography

Texture spectrum coupled with entropy and homogeneity image features for myocardium muscle characterization

People in middle/later age often suffer from heart muscle damage due to coronary artery disease associated to myocardial infarction. In young people, the genetic forms of cardiomyopathies (heart muscle disease) are the utmost protuberant cause of myocardial disease. Accurate early detected information regarding the myocardial tissue structure is a key answer for tracking the progress of several myocardial diseases. The present work proposes a new method for myocardium muscle texture classification based on entropy, homogeneity and on the texture unit-based texture spectrum approaches. Entropy and homogeneity are generated in moving windows of size 3x3 and 5x5 to enhance the texture features and to create the premise of differentiation of the myocardium structures. Texture is then statistically analyzed using the texture spectrum approach. Texture classification is achieved based on a fuzzy c–means descriptive classifier. The noise sensitivity of the fuzzy c–means classifier is overcome by using the image features. The proposed method is tested on a dataset of 80 echocardiographic ultrasound images in both short-axis and long-axis in apical two chamber view representations, for normal and infarct pathologies. The results established that the entropy-based features provided superior clustering results compared to homogeneity

Aerospace medicine and biology: A continuing bibliography with indexes, supplement 218, April 1981

This bibliography lists 161 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1981

Prevalence and etiologies of pulmonary hypertension at Somalia-Turkey Training and Research Hospital in Mogadishu

Introduction: pulmonary hypertension (PH) is one of the leading causes of mortality in the world. This study aimed to determine the ratio distribution and etiological characteristics of PH in Somalia-Turkey Training and Research Hospital. Methods: the study was designed as a hospital-based retrospective observational study and included 260 patients who were diagnosed with PH by transthoracic echocardiography (TTE) in the cardiology outpatient clinic in Somalia-Turkey Training and Research Hospital in Mogadishu. Sociodemographic and clinical characteristics and data on morbidity were retrieved from clinical records. Results: the echocardiographic prevalence of PH was found to be 18% (n=260). PH due to left heart disease was the most common form of PH (n=151, 58%), followed by PH due to lung disease (n=61, 23%), group 1 PH (n=38, 16%), group 5 PH (n=7, 2%), and chronic thromboembolic PH (CTEPH) (n=3, 1%). Conclusion: the present study showed that the prevalence of PH in Somalia is relatively higher than the rest of the world's average. The distribution characteristics of the disease could be related to the region-specific differences of the causative diseases. Further studies are needed to better capture the epidemiology of PH in Somalia

Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) is one of the most common congenital diseases, affecting 1–2% of the general population. Although most of them are sporadic, some familial cases have also been detected. BAV is a complex developmental and progressive pathology, which may present with various clinical findings from newborn to adulthood. It may be suspected during cardiac auscultation or may be diagnosed by echocardiography incidentally. Some BAV cases may remain symptomless for years, with findings like valvular stenosis, insufficiency, or dilatation in the ascending aorta, whereas some others may present with early severe aortic valve dysfunction, premature congestive heart failure, and aortic aneurysms even in the newborn period. Such heterogeneous presentations of BAV phenotypes may be associated with congenital, genetic, and/or connective tissue abnormalities. The natural course of BAV is nonpredictable, it may lead to severe morbidity and mortality

Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 153)

This bibliography lists 175 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1976