Search results for " atrium"
showing 10 items of 35 documents
Effect of intravenous flecainide on atrial vulnerability in man.
1983
Sixteen patients were investigated by means of programmed atrial stimulation at two different driving rates: 100 and 120/min. All patients had an increased atrial vulnerability at both driving rates. After intravenous flecainide application (1 mg/kg body weight as a bolus followed by the same amount given by infusion over a period of 20 min) the increased vulnerability was abolished in 11 and 9 patients respectively. In the remaining patients the rate of induced atrial tachyarrhythmia decreased. These findings correlate with a significant prolongation of the effective refractory period of the right atrium and a significant shortening of the relative refractory period of the right atrium. It…
Wave similarity mapping shows the spatiotemporal distribution of fibrillatory wave complexity in the human right atrium during paroxysmal and chronic…
2005
Introduction: The complexity of waveforms during atrial fibrillation may reflect critical activation patterns for the arrhythmia perpetuation. In this study, we introduce a novel concept of map, based on the analysis of the wave morphology, which gives a direct evidence in the human right atrium on the spatiotemporal distribution of fibrillatory wave complexity in paroxysmal (PAF) and chronic (CAF) atrial fibrillation. Methods and Results: Electrograms were recorded from a 64-electrode catheter in the right atrium of 15 patients during PAF (n = 8) and CAF (n = 7). Wave similarity maps were constructed by calculating the degree of morphological similarity of activation waves (S) at each atri…
Implantation Strategy of the Atrial Dipole Impacts Atrial Sensing Performance of Single Lead VDD Pacemakers
2002
WIEGAND, U.K.H., et al.: Implantation Strategy of the Atrial Dipole Impacts Atrial Sensing Perfor-mance of Single Lead VDD Pacemakers. Intermittent atrial undersensing is observed in a considerable percentage of patients with single lead VDD pacemakers. Analyzing the 2-year data of the Saphir Multicenter Follow-Up Study, the authors investigated predictors for the occurrence of undersensing. The study included 194 patients with high degree AV block who received a VDD pacemaker system with an identical sensing amplifier. Placement strategy of the atrial dipole was left to the discretion of the implanting physician. At the final position, atrial potential amplitudes were measured during deep …
Per una lettura socio-economica dei contesti abitativi: L’insula I del Quartiere ellenistico-romano di Agrigento. La domus I A – I B
2021
In linea con le ultime ricerche organizzate dal Parco Archeologico Regionale Valle dei Templi di Agrigento, il cui scopo è la conoscenza dell'antica città di Akragas/Agrigentum come sistema integrato e unitario, si è dedicata nuova attenzione alle forme dell'abitare, in particolare nell'area del cosiddetto "Quartiere ellenistico-romano". Quest'area fu scavata negli anni '50 e '60 del secolo scorso, ma è con la pubblicazione di E. De Miro, avvenuta solo nel 2009, che è stato possibile conoscere i risultati delle indagini. In questo contributo ci si vuole concentrare sull'isolato I del Quartiere, contraddistinto da due grandi abitazioni (I A/B e I E/F) che dominano l'area pubblica dell'agorà.…
Safety and efficacy of left atrial appendage occlusion with the ACP or Watchman device guided by intracardiac echocardiography from the left atrium
2021
Abstract Background There is a paucity of randomized data regarding the safety and efficacy of the use of intracardiac echocardiography (ICE) from the left atrium (LA) to guide left atrial appendage occlusion (LAAO) procedures under local anesthesia using either of the available devices. Hypothesis The aim of this study was to compare the efficacy and safety of ICE from the LA with transesophageal echocardiography (TEE) for guidance during transcatheter LAAO procedures. Methods Single‐center, cohort study of patients undergoing LAAO with the Amplatzer Cardiac Plug or Watchman device. Procedures were guided by ICE from the LA with local anesthesia (n = 175) or TEE under general anesthesia (n…
Left atrial strain and left atrial stiffness for early detection of cardiotoxicity in cancer patients
2021
Abstract Background Anti-cancer drugs can cause cardiovascular complications. Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) are usually used to identify clinical and subclinical cardiotoxicity. Purpose The aim of our study was to assess the addictional role of left atrial reservoir strain (LAS-S) and left atrial stiffness (LASI – the ratio of E/e' to LAS-S) in identifying patients at higher risk of cardiotoxicity. Methods 102 breast cancer patients (median age 53±9.5 years), without cardiovascular diseases, were enrolled before starting chemotherapy. Electrocardiogram and transthoracic echocardiogram (conventional measurements based on EACVI recommendations;…
Comparison of Nonclassic and Classic Phenotype of Hypertrophic Cardiomyopathy Focused on Prognostic Cardiac Magnetic Resonance Parameters: A Single-C…
2022
Patients with nonclassic phenotypes (NCP)—more advanced stages of hypertrophic cardiomyopathy (HCM)—constitute an intriguing and heterogeneous group that is difficult to diagnose, risk-stratify, and treat, and often neglected in research projects. We aimed to compare cardiac magnetic resonance (CMR) parameters in NCP versus classic phenotypes (CP) of HCM with special emphasis given to the parameters of established and potential prognostic importance, including numerous variables not used in everyday clinical practice. The CMR studies of 88 patients performed from 2011 to 2019 were postprocessed according to the study protocol to obtain standard and non-standard parameters. In NCP, the late …
Effect of DB-c-AMP on mechanical characteristics of ventricular and atrial preparations of several mammalian species
1974
Conflicting results exist about the influence of cyclic N6-2′-O-dibutyryl-AMP (DB-c-AMP) on myocardial contractile force. The present study was designed to examine whether the positive inotropic action of DB-c-AMP is restricted to certain model preparations or whether it can be assumed to represent a more general effect of the drug. Therefore, the effects of DB-c-AMP on myocardial force and on various parameters of the isometric contraction curve were examined in isolated electrically driven (0.5–2Hz) ventricular and atrial preparations of several mammalian species (cat, rabbit, calf, sheep, rat and guinea-pig). The following results were obtained:
Atrial fibrillation in highly trained endurance athletes — Description of a syndrome
2016
Atrial fibrillation (AF) is the most common heart arrhythmia, the risk of which typically increases with age. This condition is commonly associated with major cardiovascular diseases and structural heart damage, while it is rarely observed in healthy young people. However, increasing evidence indicates that paroxysmal AF can also onset in young or middle-aged and otherwise healthy endurance athletes (e.g., cyclists, runners and cross-country skiers). Here we review the topic of AF associated with strenuous endurance exercise (SEE), for example cycling, running and cross-country skiing, especially at a competitive level, and we propose the definition of a new syndrome based on the accumulati…