Search results for " Atri"
showing 10 items of 304 documents
Effect of intravenous flecainide on atrial vulnerability in man.
1985
Sixteen patients were investigated by means of programmed atrial stimulation at 2 different driving rates: 100/min and 120/min. All patients had an increased atrial vulnerability at both driving rates. After the administration of intravenous flecainide (1 mg/kg bodyweight as a bolus, followed by the same amount infused over a period of 20 minutes), 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 corresponding significant shortening of its relative refractory period. …
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…
Increased prevalence of cardiac arrhythmias and transient episodes of myocardial ischemia in hypertensives with left ventricular hypertrophy but with…
1997
To evaluate the behavior of cardiac arrhythmias (CA) and transient episodes of myocardial ischemia (TEMI), in relation to the circadian pattern of blood pressure in patients suffering from arterial hypertension, with or without echocardiographically ascertained left ventricular hypertrophy (LVH), we studied 128 patients, 87 men (M) and 41 women (F), aging from 21 to 76 years, subdivided into two groups: Group I, including 66 patients with LVH (45 M and 21 F; mean age of 53.7 ± 9.1 years; Group II, including 62 patients without LVH ( 42 M and 20 F; mean age of 49.7 ± 9.5 years). Office blood pressure (OBP) as well as nighttime ambulatory blood pressure (ABP) were higher in patients with LVH …
Gabor frames for classification of paroxysmal and persistent atrial fibrillation episodes
2016
[EN] In this study, we propose a new classification method for early differentiation of paroxysmal and persistent atrial fibrillation episodes, i.e. those which spontaneously or with external intervention will return to sinus rhythm within 7 days of onset from the ones where the arrhythmia is sustained for more than 7 days. Today, clinicians provide patients classification once the course of the arrhythmia has been disclosed. This classification problem is dealt with in this study. We study a sparse representation of surface electrocardiogram signals by means of Gabor frames and afterwards we apply a linear discriminant analysis. Thus, we provide an early discrimination, obtaining promising…
Detection of spontaneous echocardiographic contrast within the left atrium by transesophageal echocardiography: spontaneous echocardiographic contrast
1986
Transesophageal echocardiography was performed in 314 patients over a period of 24 months using a 3.5 MHz phased-array system fitted to the distal end of a conventional 12 mm endoscope. In 12 patients (2.6%) transesophageal echocardiography could not be performed because of adverse reaction to the gastroscopic procedure. Side effects were a transient A-V block in one patient and asthmatic attack in another. Mitral valve lesions were found in 99 of 314 patients. In 9 of these 99 patients (11%), including 1 patient with mitral valve stenosis and sinus rhythm, 2 with atrial fibrillation, 3 with disc, and 3 with porcine mitral prosthesis, spontaneous echocardiographic contrast was found within …
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…
Genetic variants associated with cardiac structure and function: a meta-analysis and replication of genome-wide association data.
2009
Context Echocardiographic measures of left ventricular (LV) structure and function are heritable phenotypes of cardiovascular disease. Objective To identify common genetic variants associated with cardiac structure and function by conducting a meta-analysis of genome-wide association data in 5 population-based cohort studies (stage 1) with replication (stage 2) in 2 other community-based samples. Design, Setting, and Participants Within each of 5 community-based cohorts comprising the EchoGen consortium (stage 1; n = 12 612 individuals of European ancestry; 55% women, aged 26-95 years; examinations between 1978-2008), we estimated the association between approximately 2.5 million single-nuc…
Assessment of atrial diastolic function in patients with hypertrophic cardiomyopathy by cine magnetic resonance imaging
2015
Purpose: This study was conducted to assess the role of atrial function by cardiac magnetic resonance (CMR) for the evaluation of diastolic physiology in patients with hypertrophic cardiomyopathy (HCM) compared to healthy controls. Materials and methods: We enrolled 23 consecutive patients affected by HCM and 43 healthy subjects as age-matched control cases (CC). CMR was performed through acquisition of cine steady-state free precession sequences using a 1.5-T scanner. Image postprocessing was carried out using Tracking Tool software. Results: Atrial volumes were significantly higher in patients with HCM compared to CC: maximum atrial volume (p = 0.007) and minimum atrial volume (p = 0.01).…
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 …
Hypoplasia of the posterior mitral valve leaflet: Don't forget to look beyond the mitral valve.
2020
Hypoplasia of the posterior mitral valve leaflet (PMVL) is a very rare finding in adulthood and can coexist with other congenital heart defects. In this image, a transesophageal echocardiography (TOE) carried out on a 59-year-old woman with a 2-month history of dyspnea revealed a hypoplastic PMVL causing severe mitral regurgitation associated with a secundum-type atrial septal defect (ASD) with left-to-right shunting. This case demonstrates how essential 3-dimensional TOE is for a comprehensive assessment of the mitral valve and to improve the diagnostic accuracy of concomitant congenital heart abnormalities.