Search results for "HEART"

Mitral valve therapy still surgical?

2015

Mitral regurgitation (MR) is the second most common valvular heart disease after aortic valve stenosis. With increased understanding of the heterogenic pathophysiology of MR, cardiac surgeons have developed various techniques that increase the likelihood of successful mitral valve repair (MVR). Nowadays, a rate of repair >90% may be reached in some mitral valve reference centres. In recent years, the introduction of transcatheter mitral valve intervention techniques has opened up new frontiers in mitral therapy, specifically in patients at high risk for standard surgery. Current percutaneous technologies for MVR have been developed on the basis of some of the surgical principles. Based on c…

Monitoring stress and recovery states: Structural and external stages of the short version of the RESTQ sport in elite swimmers before championships

2016

Background: Psychological stress and recovery monitoring is a key issue for increasing athletes' health, well-being, and performance. This multi-study report examined changes and the dose–response relationships between recovery–stress psychological states, training load (TL), heart rate (HR), heart rate recovery (HRR), and heart rate variability (HRV) while providing evidence for the factorial validity of a short French version of the Recovery–Stress Questionnaire for Athletes (RESTQ-36-R-Sport). Methods: Four hundred and seventy-three university athletes (Study 1), 72 full expert swimmers (Study 2), and 11 national to international swimmers (Study 3) participated in the study. Data were an…

Neuronal and extraneuronal uptake and efflux of catecholamines in the isolated rabbit heart

1974

1. Isolated rabbit hearts were perfused with (−)-noradrenaline, (−)-adrenaline and (±)-isoprenaline for various time periods (1–180 min) and then washed with an amine-free medium. The venous concentration of the amine was estimated fluorimetrically during the infusion and after its end, to study removal and efflux, respectively. 2. In untreated hearts and after pretreatment with reserpine the removal had a constant rate over 20–60 min. After pretreatment with pargyline to block monoamine oxidase (MAO), however, the removal of noradrenaline declined exponentially to zero. Inhibition of the neuronal uptake (desipramine) and chemical sympathectomy (6-hydroxydopamine) abolished the removal of n…

The neuronal efflux of noradrenaline: Dependency on sodium and facilitation by ouabain

1974

Rabbit hearts were isolated after pretreatment with the MAO inhibitor pargyline and with reserpine and were perfused with 200 ng/ml noradrenaline for 1 h. During the subsequent wash-out with an amine-free solution for 2 h, the neuronal efflux of noradrenaline declined mono-exponentially with a mean halftime of 42 min. Both Na+-free solution and ouabain caused facilitation of the efflux which thereafter declined in a multi-exponential fashion. The maximum facilitation was reached after 3 min of Na+-free perfusion and 25 min after introduction of ouabain. The amount of exogenous noradrenaline accumulated in the heart was only partially released when the extracellular Na+-concentration was nor…

RELEASE OF CATECHOLAMINES FROM THE HEART

1966

Publisher Summary This chapter discusses the release of catecholamines from the heart. The isolated heart of the rabbit with the sympathetic nervous supply from the right stellate ganglion intact was set up according to Hukovio and Muscholl. The ganglion was stimulated for 30 s at supramaximal voltage with rectangular impulses of 3–5 ms duration a frequency of 10 shocks/s. Each stimulation period was followed by a resting period of 30 s. In the rabbit, four doses of 50 mg/kg l-α-methyldopa decreased the noradrenaline concentration in auricles, right, and left ventricles by 38–60%. An equimolar amount of α-methyl noradrenaline was detected in the tissues. Reserpine and guanethidine in doses,…

2018

Background The aim of our study was to evaluate the feasibility of exercise cardiac magnetic resonance (CMR) in patients with repaired tetralogy of Fallot (RTOF) and to assess right and left ventricular adaptation and aortic wall response to exercise in comparison with volunteers. Methods 11 RTOF and 11 volunteers underwent prospective CMR at rest and during exercise. A supine bicycle ergometer was employed to reach twice the resting heart rate during continuous exercise, blood pressure and heart rate were recorded. Bi-ventricular parameters and aortic stiffness were assessed using accelerated cine sequences and flow-encoding CMR. A t-test was used to compare values between groups. A Mann W…

Transcatheter Vs. Surgical Closure of Atrial Septal Defects in Adults

2018

Abstract Percutaneous transcatheter device closure of secundum atrial septal defects (ASD) has now largely replaced surgical closure in most centres. The aim of this study was to compare results of transcatheter and surgical ASD closure in adults in Latvia during the years 2002–2014 and to analyse long-term outcomes of transcatheter closure. We analysed data from 334 patients with secundum ASD who underwent ASD closure in Pauls Stradiņš Clinical University Hospital. Patients were included into device or surgical closure groups. In the device group, three follow-ups were made 1, 6, and 12 months after the procedure. No follow-up data were available for surgical arm patients beyond their hosp…

Evaluation of the Complexity of Myocardial Activation During Ventricular Fibrillation. An Experimental Study

2013

A B S T R A C T Introduction and objectives: An experimental model is used to analyze the characteristics of ventricular fibrillation in situations of variable complexity, establishing relationships among the data produced by different methods for analyzing the arrhythmia. Methods: In 27 isolated rabbit heart preparations studied under the action of drugs (propranolol and KB-R7943) or physical procedures (stretching) that produce different degrees of change in the complexity of myocardial activation during ventricular fibrillation, use was made of spectral, morphological, and mapping techniques to process the recordings obtained with epicardial multielectrodes. Results: The complexity of ve…

Clinical utility of antigen carbohydrate 125 for planning the optimal length of stay in acute heart failure.

2021

BACKGROUND: The optimal length of stay (LOS) in patients hospitalized for acute heart failure (AHF) remains controversial. Plasma antigen carbohydrate 125 (CA125) has emerged as a reliable proxy of congestion. We aimed to evaluate whether there is a differential impact of LOS on the risk of 6-month AHF readmission across CA125 levels. METHODS: This is a retrospective study that included 1,387 patients discharged for AHF in two third-level centers. CA125 was measured 48±24h after admission. The association between CA125 and LOS with the risk of subsequent AHF readmission at 6 months was analyzed by Cox regression analysis accounting for death as a competing event. RESULTS: The median (IQR) a…

Preparation, Execution and Experience: A Multivariate Evaluation of ANS-SNS Patterns

1985

Aims to verify with multivariate methods how autonomic-somatic changes (composed by skin conductance, heart rate, pulse amplitude, respiration, blood volume and flexor, frontal and orbicutaris oris EMG-measures) from specific patterns according to event-related demands both during (or after) and before events when contentual and temporal knowledge allowing preparation is varied.