Diagnostik kardiovaskulärer Erkrankungen mit Hilfe der suprasternalen M-mode Echokardiographie

Summary The suprasternal approach can be used to image the aortic arch, the right pulmonary artery and the left atrium. Dilatation or dissections involving the aortic arch were detected echocardiographically from the suprasternal notch. The echocardiogram of the right pulmonary artery is altered in cases of acute and chronic pulmonary hypertension. Intrapulmonary thrombi in patients with acute pulmonary embolism were visualized with this technique. A volume overloading of the pulmonary circulation due to a congenital left to right shunt, as well as a decreased pulmonary blood flow due to a congenital right to left shunt causes characteristic changes in the wall motion pattern of the right pulmonary artery. Hypoplasia or aplasia of the central pulmonary arteries can be diagnosed as well. Imaging of the left atrium from the suprasternal notch may help to differentiate between supraventricular and ventricular rhythm disturbances. The suprasternal approach is therefore recommended to be used as a routine part of each echocardiographic examination.

---

Abkürzungen AO_d enddiastolischer Diameter der Aorta - AO_s mittsystolischer Diameter der Aorta - ASD Vorhofseptumdefekt - AO Aorta - DCM dilative Kardiomyopathie - F₄ Fallot'sche Tetralogie - LA linker Vorhof - NP Normalperson - PH pulmonale Hypertonie - PI Pulmonalinsuffizienz - PSE_AO prozentuale systolische Erweiterung der Aorta - PSE_RPA prozentuale systolische Erweiterung der rechten Pulmonalarterie - PAD_m mittlerer Pulmonalarteriendruck - PC praecordial - Q_RPA maximale Zunahme der Querschnittsfläche der rechten Pulmonalarterie während der Systole - RPA_d end-diastolischer Diameter der rechten Pulmonalarterie - RPA_s mittsystolischer Diameter der rechten Pulmonalarterie - SS suprasternal - SX subxiphoidal Teile der Arbeit wurden durch das BMFT-Projekt 01ZSO31-ZA/NT02 gefördert     

Comparison of Discrete Cardiovascular Fitness Groups on Plasma Catecholamine and Selected Behavioral Responses to Psychological Stress

Discrete cardiovascular fitness groups consisting of high-fit (n=10) and low-fit (n=9) men performed a well-learned vigilance task and their self-report, performance, and plasma catecholamine responses were compared. No significant differences were observed between the fitness groups on self-report or psychomotor performance responses to the vigilance task. However, the low-fit group took significantly longer than high-fit subjects to complete the first of three sets of anagrams administered immediately after the vigilance task. Plasma norepinephrine but not epinephrine response was greater in the low-fit group compared to their high-fit counterparts. The findings indicate that enhanced cardiovascular fitness may be characterized by an attenuated plasma norepinephrine response to a vigilance task with sustained cognitive performance subsequent to the task.     

Defensive hostility and anger expression: Relationship to additional heart rate reactivity during active coping

The main purpose of the present study was twofold: (a) to assess the relationship between defensive hostility (high hostility/high defensiveness) and additional heart rate reactivity during active coping and (b) to determine if the construct of anger-out might lend additional, sensitivity to the predictive power of the defensive hostility model. Forty individuals were randomly assigned to complete a mental arithmetic task with or without the threat of shock. Participants also completed the Cook-Medley Hostility Inventory (Ho), the Marlowe-Crowne Social Desirability Scale (MC), and the Spielberger Anger Expression Scale. Defensive hostile subjects (high Ho/high MC) were significantly more reactive than any other subgroup. In addition, the combination of low Ho/high anger-out scores yielded a subgroup significantly less reactive than any other subgroup. These findings clarify the complex relationship of hostility and cardiovascular reactivity.     

PCSK9 inhibition with alirocumab in pediatric patients with heterozygous familial hypercholesterolemia: The ODYSSEY KIDS study

1. Download : Download high-res image (435KB)
2. Download : Download full-size image

     

Does Low FEV1 in Addition to Fixed Ratio and/or Lower Limit of Normal of FEV1/FVC Improve Prediction of Mortality in COPD? The NHANES-III-linked-mortality Cohort

Purpose

There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.

3D MRI-Based Multicomponent FSI Models for Atherosclerotic Plaques

A three-dimensional (3D) MRI-based computational model with multicomponent plaque structure and fluid-structure interactions (FSI) is introduced to perform mechanical analysis for human atherosclerotic plaques and identify critical flow and stress/strain conditions which may be related to plaque rupture. Three-dimensional geometry of a human carotid plaque was reconstructed from 3D MR images and computational mesh was generated using Visualization Toolkit. Both the artery wall and the plaque components were assumed to be hyperelastic, isotropic, incompressible, and homogeneous. The flow was assumed to be laminar, Newtonian, viscous, and incompressible. The fully coupled fluid and structure models were solved by ADINA, a well-tested finite element package. Results from two-dimensional (2D) and 3D models, based on ex vivo MRI and histological images (HI), with different component sizes and plaque cap thickness, under different pressure and axial stretch conditions, were obtained and compared. Our results indicate that large lipid pools and thin plaque caps are associated with both extreme maximum (stretch) and minimum (compression when negative) stress/strain levels. Large cyclic stress/strain variations in the plaque under pulsating pressure were observed which may lead to artery fatigue and possible plaque rupture. Large-scale patient studies are needed to validate the computational findings for possible plaque vulnerability assessment and rupture predictions.     

Change in sympathetic activity,cardiovascular functions and plasma hormone concentrations due to cold water immersion in men

The purpose of this study was to determine whether or not repeated short-term cold water immersions can induce a change in the activity of the sympathetic nervous system and, consequently, in cardiovascular functions in healthy young athletes. Changes in some plasma hormone concentrations were also followed. A single cold water immersion (head-out, at 14°C, for 1 h) increased sympathetic nervous system activity, as evidenced by a four-fold increase (P < 0.05) in plasma noradrenaline concentration. Plasma adrenaline and dopamine concentrations were not increased significantly. Plasma renin-angiotensin activity was reduced by half (P < 0.05) during immersion but plasma aldosterone concentration was unchanged. Stimulation of the sympathetic nervous system during immersion did not induce significant changes in heart rate, but induced peripheral vasoconstriction (as judged from a decrease in skin temperature) and a small increase (by 10%) in systolic and diastolic blood pressures. No clear change in reactivity of the sympathetic nervous system was observed due to repeated cold water immersions (three times a week, for 6 weeks). Neither the plasma renin-angiotensin activity, aldosterone concentration nor cardiovascular parameters were significantly influenced by repeated cold water immersions. A lowered diastolic pressure and an increase in peripheral vasoconstriction were observed after cold acclimation, however. Evidently, the repeated cold stimuli were not sufficient to induce significant adaptational changes in sympathetic activity and hormone production.     

Physiological Detection of Deception: Measurement of Responses to Questions and Answers During Countermeasure Maneuvers

Physiological detection of deception (“lie detection”) procedures were evaluated with 24 actors, half of whom were “guilty” of a mock-crime and half were “innocent.” All subjects were trained in the Stanislavsky method of acting and were instructed to use this method to appear innocent on the polygraph test. Two versions of the control question detection of deception test were employed: one in which subjects verbally answered immediately following each question and the other in which they delayed their verbal answer for 8 sec following each question. The delayed answer technique allowed the separate measurement of physiological responses to the questions and the answers. Skin resistance responses, cardiovascular changes, and respiration were recorded and analyzed. Excluding inconclusive results, the overall accuracy of the decisions varied between 78% and 91% depending on the test employed. The principal results were: 1) attempts by guilty subjects to appear innocent were totally ineffective, 2) physiological responses elicited by the questions were more valid indicators of deception and nondeception than were the responses elicited by the verbal answers, and 3) errors occurred more frequently with innocent subjects (between 17% and 25% depending on the measure used) than with guilty subjects (0% with each measure). Variables which may affect the generalizability of these results to the field situation are discussed and suggestions for increasing the generalizability of laboratory findings are made.     

Vortex Shedding in Steady Flow Through a Model of an Arterial Stenosis and Its Relevance to Mural Platelet Deposition

In this study, the development of unsteady vortical formations in the separated flow region distal to a stenosis throat is presented and compared with the platelet deposition measurements, to enhance our understanding of the mechanisms involved in platelet kinetics in flowing blood. Qualitative and quantitative flow visualization and numerical simulations were performed in a model of a streamlined axisymmetric stenosis with an area reduction of 84% at the throat of the stenosis. Measurements were performed at Reynolds numbers (Re), based on upstream diameter and average velocity, ranging from 300 to 1800. Both the digital particle image visualization method employed and the numerical simulations were able to capture the motion of the vortices through the separated flow region. Periodic shedding of vortices began at approximately Re=375 and continued for the full range of Re studied. The locales at which these vortices are initiated, their size, and their life span, were a function of Re. The numerical simulations of turbulent flow through the stenosis model entailed a detailed depiction of the process of vortex shedding in the separated flow region downstream of the stenosis. These flow patterns were used to elucidate the mechanisms involved in blood platelet kinetics and deposition in the area in and around an arterial stenosis. The unsteady flow development in the recirculation region is hypothesized as the mechanism for observed changes in the distribution of mural platelet deposition between Re=300, 900, and 1800, despite only a marginal variation in the size and shape of the recirculation zone under these flow conditions. © 1999 Biomedical Engineering Society. PAC99: 8719Uv, 8710+e