Search results for "Atrial"

Effects of chronic exercise on myocardial refractoriness: a study on isolated rabbit heart

2008

Aim:  To determine whether chronic physical training increases atrial and ventricular refractoriness in isolated rabbit heart. Methods:  Trained rabbits were submitted to a protocol of treadmill running. The electrophysiological parameters of refractoriness investigated in an isolated heart preparation were: (1) atrial effective refractory period (AERP) and atrial functional refractory period and ventricular effective and functional refractory periods (VERP and VFRP) using the extrastimulus technique at four different pacing cycle lengths; (2) the dominant frequency (DF) of ventricular fibrillation (VF). A multi-electrode plaque containing 256 electrodes and a spectral method were used to o…

From 12 to 1 ECG lead: multiple cardiac condition detection mixing a hybrid machine learning approach with a one-versus-rest classification strategy

2022

Abstract Objective. Detecting different cardiac diseases using a single or reduced number of leads is still challenging. This work aims to provide and validate an automated method able to classify ECG recordings. Performance using complete 12-lead systems, reduced lead sets, and single-lead ECGs is evaluated and compared. Approach. Seven different databases with 12-lead ECGs were provided during the PhysioNet/Computing in Cardiology Challenge 2021, where 88 253 annotated samples associated with none, one, or several cardiac conditions among 26 different classes were released for training, whereas 42 896 hidden samples were used for testing. After signal preprocessing, 81 features per ECG-le…

Cross-Sectional Associations between Homoarginine, Intermediate Phenotypes, and Atrial Fibrillation in the Community—The Gutenberg Health Study

2018

Homoarginine has come into the focus of interest as a biomarker for cardiovascular disease. Atrial fibrillation (AF) causes a substantial increase in morbidity and mortality. Whether circulating homoarginine is associated with occurrence or persistence of AF and may serve as a new predictive biomarker remains unknown. We measured plasma levels of homoarginine in the population-based Gutenberg health study (3761 patients included, of them 51.7% males), mean age 55.6 &plusmn

Intake of Vitamin K Antagonists and Worsening of Cardiac and Vascular Disease: Results From the Population‐Based Gutenberg Health Study

2018

Background Preclinical data have indicated a link between use of vitamin K antagonists ( VKA ) and detrimental effects on vascular structure and function. The objective of the present study was to determine the relationship between VKA intake and different phenotypes of subclinical cardiovascular disease in the population. Methods and Results Clinical and laboratory data, as well as medical–technical examinations were assessed from 15 010 individuals aged 35 to 74 years during a highly standardized 5‐hour visit at the study center of the population‐based Gutenberg Health Study. In total, the study sample comprised 287 VKA users and 14 564 VKA nonusers. Multivariable analysis revealed an in…

Novel Analgesic Agents Obtained by Molecular Hybridization of Orthosteric and Allosteric Ligands

2019

AbstractDespite the high incidence of acute and chronic pain in the general population, the efficacy of currently available medications is unsatisfactory. Insufficient management of pain has a profound impact on the quality of life and can have serious physical, psychological, social, and economic consequences. This unmet need reflects a failure to develop novel classes of analgesic drugs with superior clinical properties and lower risk of abuse. Nevertheless, recent advances in our understanding of the neurobiology of pain are offering new opportunities for developing different therapeutic approaches. Among those, the activation of M2 muscarinic acetylcholine receptors, which play a key ro…

Episodes of second-degree ventriculo-atrial block during ventricular tachycardia

2017

Incidence, determinants and prognostic relevance of dyspnea at admission in patients with Takotsubo syndrome: results from the international multicen…

2020

AbstractClinical presentation of Takotsubo syndrome (TTS) may range from acute chest pain to dyspnea: the prognostic role of clinical onset is still controversial. Aim of this study was therefore to investigate the prognostic relevance of dyspnea at presentation in patients with TTS. We analyzed 1,071 TTS patients (median age 72 years, 90% female) enrolled in the international multicenter GEIST registry. Patients were divided according to the presence or absence of dyspnea at hospital admission, as clinically assessed by the accepting physician. The primary endpoint was occurrence of in-hospital complications defined as a composite of pulmonary edema, cardiogenic shock and death. Overall, 3…

Exome sequencing of a family with lone, autosomal dominant atrial flutter identifies a rare variation in ABCB4 significantly enriched in cases

2015

Background Lone atrial flutter (AFL) and atrial fibrillation (AF) are common and sometimes consequential cardiac conduction disorders with a strong heritability, as underlined by recent genome-wide association studies that identified genetic modifiers. Follow-up family-based genetic analysis also identified Mendelian transmission of disease alleles. Three affected members were exome-sequenced for the identification of potential causative mutations, which were subsequently validated by direct sequencing in the other 3 affected members. Taqman assay was then used to confirm the role of any mutation in an independent population of sporadic lone AFL/AF cases. Results The family cluster analysis…

Characterization of the muscarinic receptor subtype(s) mediating contraction of the guinea-pig lung strip and inhibition of acetylcholine release in …

1997

1 The muscarinic receptor subtypes mediating contraction of the guinea-pig lung strip and inhibition of the release of acetylcholine from cholinergic vagus nerve endings in the guinea-pig trachea in vitro have previously been characterized as M-2-like, i.e. having antagonist affinity profiles that are qualitatively similar but quantitatively dissimilar compared to cardiac M-2 receptors. The present study sought to establish definitely the identity of these receptor subtypes by using the selective muscarinic receptor antagonist, tripitramine. Guinea-pig atria and guinea-pig trachea (postjunctional contractile response) were included for reference.2 It was found that tripitramine antagonized …

Impact of frailty and atrial fibrillation in elderly patients with acute coronary syndromes

2021

Background: There is scarce information on the prognostic role of frailty and Atrial Fibrillation (AF) in elderly patients Acute Coronary Syndrome (ACS). Methods: The aim was to analyse the management of elderly patients with frailty and AF who suffered an ACS using data of the prospective multicentre LONGEVO-SCA registry. We evaluated the predictive performance of FRAIL, Charlson scores and AF status for adverse events at 6 months follow-up. Results: A total of 531 unselected patients with ACS and above 80 years old [mean age 84.4 (SD=3.6) years; 322 (60.6%) male] were enrolled, of whom 128 (24.1%) with AF and 145 (27.3%) with frailty. Mutually exclusive number of patients were as follows:…