Search results for "Heart Atria"
showing 10 items of 78 documents
CSF shunt infections in children
1993
The incidence of shunt infections and possible risk factors was investigated by chart analysis. From 1986 to 1989 350 shunt procedures were performed including 273 ventriculoperitoneal shunts and 75 ventriculoatrial shunts. Twenty-eight infectious episodes (8%) occurred in 25 patients during a median follow-up time of 20 months. For 204 patients the follow-up time could be prolonged until September 1992. In these patients no infectious episodes occurred in the extended observation period. In 24 cases (85.7%) a causative organism could be isolated. The infecting organisms were gram-positive cocci in 22 cases (78.6%) and gram-negative bacilli in two cases. The main signs and symptoms were fev…
Brain and kidney, victims of atrial microembolism in elderly hospitalized patients? Data from the REPOSI study
2015
Abstract Background It is well known that atrial fibrillation (AF) and chronic kidney disease (CKD) are associated with a higher risk of stroke, and new evidence links AF to cognitive impairment, independently from an overt stroke (CI). Our aim was to investigate, assuming an underlying role of atrial microembolism, the impact of CI and CKD in elderly hospitalized patients with AF. Methods We retrospectively analyzed the data collected on elderly patients in 66 Italian hospitals, in the frame of the REPOSI project. We analyzed the clinical characteristics of patients with AF and different degrees of CI. Multivariate logistic analysis was used to explore the relationship between variables an…
Echocardiographic reference ranges for normal left atrial function parameters results from the EACVI NORRE study
2018
International audience; Aims - To obtain the normal ranges for echocardiographic measurements of left atrial (LA) function from a large group of healthy volunteers accounting for age and gender. Methods and results - A total of 371 (median age 45 years) healthy subjects were enrolled at 22 collaborating institutions collaborating in the Normal Reference Ranges for Echocardiography (NORRE) study of the European Association of Cardiovascular Imaging (EACVI). Left atrial data sets were analysed with a vendor-independent software (VIS) package allowing homogeneous measurements irrespective of the echocardiographic equipment used to acquire data sets. The lowest expected values of LA function we…
The total absence of atrial automaticity in a child with sinus node dysfunction
2007
Background A routine sports evaluation identified constant alternation between a junctional and idioventricular rhythm in a 9-year-old child. During exercise testing, electrography demonstrated that the child was in junctional rhythm without any apparent P waves, and had a reduced increase in heart rate. Endocardial atrial pacing captured the atrium and demonstrated that atrioventricular conduction was normal, but the recovery time of the ectopic rhythm was very long. Three-dimensional electrophysiological mapping revealed 1:1 retrograde homogeneous conduction through the right atrium. Investigations Electrocardiography, Holter monitoring, echocardiography, exercise stress testing, atrial p…
Left atrial thrombi despite anticoagulant and antiplatelet therapy
1994
To investigate risk factors for embolization in patients with echocardiographically detected left atrial thrombi and to evaluate thrombus development, we examined 29 patients with transesophageal and transthoracic echocardiography at two points during a follow-up of 18 months. We compared patients with a history of possible arterial embolization (n = 13) with those without (n = 16) in regard to age, gender, left atrial dilatation, localization of the thrombus in the left atrial cavity, spontaneous echo contrast, and atrial fibrillation. Eight patients were treated with aspirin, 20 with phenprocoumon. Only left atrial spontaneous contrast was associated with thromboembolism (10/15 patients w…
Gerbode-type left ventricular outflow tract to right atrial fistula complicating prosthetic aortic valve replacement identified by cardiac computed t…
2012
Abstract Acquired left ventricular-right atrial communication ( Gerbode-type defect) is a rare complication of infective endocarditis. Although transesophageal echocardiography remains the technique of choice for the evaluation of complications of endocarditis this case highlights the usefulness of cardiac computed tomography in this scenario, particularly in cases where assessment of coronary anatomy is required before surgery.
Modulation of cytosolic free calcium concentration by ?1-adrenoceptors in rat atrial cells
1992
The effects of α1-adrenoceptor stimulation by phenylephrine (PE) and β-adrenoceptor stimulation by isoprenaline (ISO) on Ca2+ current (ICa) and free intracellular Ca2+ concentration ([Ca2+]i) were studied in isolated atrial myocytes from rat hearts. PE did not significantly affect the magnitude of ICa, whereas large increases of peak ICa were observed in response to ISO. In electrically driven cells, PE evoked a concentration-dependent, gradual increase in diastolic [Ca2+]i and, initially, an increase in the height of peak [Ca2+]i transients. When the diastolic [Ca2+]i was increased to a greater extent, the amplitude of [Ca2+]i transients was decreased. Simultaneous measurements of [Ca2+]i …
A useful muscarinic parameter and the differential recording of atrial and ventricular tension in the perfused rabbit heart
1971
1. A simple method of recording right atrial tension from the Langendorff perfused rabbit has been described; it is based on the “transverse” method of recording cardiac contractions described by Beckett (1970). 2. Right atrial and ventricular tensions were recorded by transducers attached to threads stitched into the right atrium and right ventricle, the heart being retained and prevented from rotating by two threads stitched into the intraventricular septum as described by Beckett. 3. Right ventricular diastolic tension was adjusted to 7.5 g. Interference with the atrial record by ventricular systole was overcome by adjustment of diastolic right atrial tension to its optimal value between…
Usefulness of regional right ventricular and right atrial strain for prediction of early and late right ventricular failure following a left ventricu…
2019
Background: Identifying candidates for left ventricular assist device surgery at risk of right ventricular failure remains difficult. The aim was to identify the most accurate predictors of right ventricular failure among clinical, biological, and imaging markers, assessed by agreement of different supervised machine learning algorithms. Methods: Seventy-four patients, referred to HeartWare left ventricular assist device since 2010 in two Italian centers, were recruited. Biomarkers, right ventricular standard, and strain echocardiography, as well as cath-lab measures, were compared among patients who did not develop right ventricular failure (N = 56), those with acute–right ventricular fail…
Depolarization-induced influx of sodium in response to phenylephrine in rat atrial heart muscle.
1991
1. The effects of alpha 1-adrenoceptor stimulation on transmembrane potential, currents and ion fluxes were investigated in multicellular preparations and/or single cells obtained from the left atrium of rat hearts. 2. In multicellular preparations, phenylephrine caused a concentration-dependent positive inotropic effect, an increase in action potential duration, and a decrease in resting potential; the effects were antagonized by phentolamine. 3. In the presence of phenylephrine (100 mumol/1), two levels of resting potential were observed when the preparations were, alternately, electrically stimulated or kept at rest (-74 +/- 1 mV during activity and -62 +/- 4 mV at rest; mean +/- S.E.M.;…