Read by QxMD icon Read

Atrial fibrillation and right atria

Yangyang Bao, B Cicero Willis, Chad R Frasier, Luis F Lopez-Santiago, Xianming Lin, Roberto Ramos-Mondragón, David S Auerbach, Chunling Chen, Zhenxun Wang, Justus Anumonwo, Héctor H Valdivia, Mario Delmar, José Jalife, Lori L Isom
BACKGROUND: Mutations in SCN2B, encoding voltage-gated sodium channel β2-subunits, are associated with human cardiac arrhythmias, including atrial fibrillation and Brugada syndrome. Because of this, we propose that β2-subunits play critical roles in the establishment or maintenance of normal cardiac electric activity in vivo. METHODS AND RESULTS: To understand the pathophysiological roles of β2 in the heart, we investigated the cardiac phenotype of Scn2b null mice...
December 2016: Circulation. Arrhythmia and Electrophysiology
Yoshiyuki Watanabe, Matthew R Schill, Toshinobu Kazui, Spencer J Melby, Richard B Schuessler, Ralph J Damiano
OBJECTIVE: Creating transmural linear lesions on the beating heart is an important component of minimally invasive surgical ablation for atrial fibrillation. Animal studies have shown poor efficacy for surface bipolar radiofrequency ablation (RFA). Clinicians have developed strategies including multiple device applications and vena caval occlusion (VCO) to improve ablation efficacy. These techniques were evaluated in an acute porcine model. METHODS: In the first experiment, an RFA device was used to perform two 40-second epicardial ablations on the right atrium of six pigs...
November 2016: Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery
Andrés Ricardo Pérez-Riera, Luiz Carlos de Abreu, Raimundo Barbosa-Barros, José Grindler, Acácio Fernandes-Cardoso, Adrian Baranchuk
P-wave dispersion (PWD, Pd or Pdis) is a noninvasive electrocardiographic (ECG) marker for atrial remodeling and predictor for atrial fibrillation (AF). PWD is defined as the difference between the widest and the narrowest P-wave duration recorded from the 12 ECG leads. Increased P-wave duration and PWD reflect prolongation of intraatrial and interatrial conduction time with lack of a well-coordinated conduction system within the atrial muscles, with inhomogeneous, asynchronic, pro-inflammatory and anti-inflammatory effect mediated by interleukin-6 (IL-6) in patients with the CG + GG genotype IL-6 -634C/G polymorphism [1] and discontinuous propagation of sinus impulses mainly between the left and right atria, interstitial/extracellular fibroblast activation and collagen deposition with fibrosis (via TGF-β) in atrial tissue, insufficient blood supply, significant not isotropic myoelectric activity, and thin wall thickness and consequent expansion tendency all well-known electrophysiological characteristics in patients with atrial arrhythmias and especially paroxysmal atrial fibrillation (PAF) [2]...
July 2016: Indian Pacing and Electrophysiology Journal
Rishi Arora, Gary L Aistrup, Stephen Supple, Caleb Frank, Jasleen Singh, Shannon Tai, Anne Zhao, Laura Chicos, William Marszalec, Ang Guo, Long-Sheng Song, J Andrew Wasserstrom
BACKGROUND: The peculiarities of transverse tubule (T-tubule) morphology and distribution in the atrium-and how they contribute to excitation-contraction coupling-are just beginning to be understood. OBJECTIVES: The objectives of this study were to determine T-tubule density in the intact, live right and left atria in a large animal and to determine intraregional differences in T-tubule organization within each atrium. METHODS: Using confocal microscopy, T-tubules were imaged in both atria in intact, Langendorf-perfused normal dog hearts loaded with di-4-ANEPPS...
September 23, 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Mimount Bourfiss, Anneline S J M Te Riele, Thomas P Mast, Maarten J Cramer, Jeroen F VAN DER Heijden, Toon A B VAN Veen, Peter Loh, Dennis Dooijes, Richard N W Hauer, Birgitta K Velthuis
INTRODUCTION: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is associated with desmosomal mutations. Although desmosomal disruption affects both ventricles and atria, little is known about atrial involvement in ARVD/C. OBJECTIVE: To describe the extent and clinical significance of structural atrial involvement and atrial arrhythmias (AA) in ARVD/C stratified by genotype. METHODS: We included 71 patients who met ARVD/C Task Force Criteria and underwent cardiac magnetic resonance (CMR) imaging and molecular genetic analysis...
December 2016: Journal of Cardiovascular Electrophysiology
Javier Barallobre-Barreiro, Shashi K Gupta, Anna Zoccarato, Rika Kitazume-Taneike, Marika Fava, Xiaoke Yin, Tessa Werner, Marc N Hirt, Anna Zampetaki, Alessandro Viviano, Mei Chong, Marshall Bern, Antonios Kourliouros, Nieves Domenech, Peter Willeit, Ajay M Shah, Marjan Jahangiri, Liliana Schaefer, Jens W Fischer, Renato V Iozzo, Rosa Viner, Thomas Thum, Joerg Heineke, Antoine Kichler, Kinya Otsu, Manuel Mayr
BACKGROUND: Myocardial fibrosis is a feature of many cardiac diseases. We used proteomics to profile glycoproteins in the human cardiac extracellular matrix (ECM). METHODS: Atrial specimens were analyzed by mass spectrometry after extraction of ECM proteins and enrichment for glycoproteins or glycopeptides. RESULTS: ECM-related glycoproteins were identified in left and right atrial appendages from the same patients. Several known glycosylation sites were confirmed...
September 13, 2016: Circulation
Asit Das, Dhiman Kahali
Adverse hemodynamics of right ventricular (RV) pacing is a well-known fact. It was believed to be the result of atrio-ventricular (AV) dyssynchrony and sequential pacing of the atrium and ventricle may solve these problems. However, despite maintenance of AV synchrony, the dual chamber pacemakers in different trials have failed to show its superiority over single chamber RV apical pacing in terms of death, progression of heart failure, and atrial fibrillation (AF). As a consequence, investigators searched for alternate pacing sites with a more physiological activation pattern and better hemodynamics...
July 2016: Indian Heart Journal
Adéla Matějková, Ivo Šteiner
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. For long time it was considered as pure functional disorder, but in recent years, there were identified atrial locations, which are involved in the initiation and maintenance of this arrhythmia. These structural changes, so called remodelation, start at electric level and later they affect contractility and morphology. In this study we attempted to find a possible relation between morphological (scarring, amyloidosis, left atrial (LA) enlargement) and electrophysiological (ECG features) changes in patients with AF...
2016: Acta Medica (Hradec Králové)
Tinen L Iles, Brian Howard, Stephen Howard, Stephen Quallich, Christopher Rolfes, Eric Richardson, Hanna R Iaizzo, Paul A Iaizzo
To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, antiarrhythmic drugs administered intravenously can produce drops in systemic pressure in the already compromised cardiac patient. While performing open-heart procedures, surgeons will often either create a small port or form a pericardial cradle to create suitable fields for operation. This access yields opportunities for target pharmacological delivery (antiarrhythmic or ischemic preconditioning agents) directly to the myocardial tissue without undesired side effects...
2016: Journal of Visualized Experiments: JoVE
Feng-Chun Tsai, Yen-Chen Lin, Shang-Hung Chang, Gwo-Jyh Chang, Yu-Juei Hsu, Yuan-Min Lin, Yun-Shien Lee, Chun-Li Wang, Yung-Hsin Yeh
BACKGROUND: Atrial fibrillation (AF) causes atrial remodeling, and the left atrium (LA) is the favored substrate for maintaining AF. It remains unclear if AF remodels both atria differently and contributes to LA arrhythmogenesis and thrombogenesis. Therefore, we wished to characterize the transcript profiles in the LA and right atrium (RA) in sinus rhythm (SR) and AF respectively. METHODS: Paired LA and RA appendages acquired from patients receiving cardiac surgery were used for ion-channel- and whole-exome-based transcriptome analysis...
November 1, 2016: International Journal of Cardiology
Ning Li, Thomas A Csepe, Brian J Hansen, Lidiya V Sul, Anuradha Kalyanasundaram, Stanislav O Zakharkin, Jichao Zhao, Avirup Guha, David R Van Wagoner, Ahmet Kilic, Peter J Mohler, Paul M L Janssen, Brandon J Biesiadecki, John D Hummel, Raul Weiss, Vadim V Fedorov
BACKGROUND: Adenosine provokes atrial fibrillation (AF) with a higher activation frequency in right atria (RA) versus left atria (LA) in patients, but the underlying molecular and functional substrates are unclear. We tested the hypothesis that adenosine-induced AF is driven by localized reentry in RA areas with highest expression of adenosine A1 receptor and its downstream GIRK (G protein-coupled inwardly rectifying potassium channels) channels (IK,Ado). METHODS: We applied biatrial optical mapping and immunoblot mapping of various atrial regions to reveal the mechanism of adenosine-induced AF in explanted failing and nonfailing human hearts (n=37)...
August 9, 2016: Circulation
Irina A Polejaeva, Ravi Ranjan, Christopher J Davies, Misha Regouski, Justin Hall, Aaron L Olsen, Qinggang Meng, Heloisa M Rutigliano, Derek J Dosdall, Nathan A Angel, Frank B Sachse, Thomas Seidel, Aaron J Thomas, Rusty Stott, Kip E Panter, Pamela M Lee, Arnaud J VAN Wettere, John R Stevens, Zhongde Wang, Rob S Macleod, Nassir F Marrouche, Kenneth L White
INTRODUCTION: Large animal models of progressive atrial fibrosis would provide an attractive platform to study relationship between structural and electrical remodeling in atrial fibrillation (AF). Here we established a new transgenic goat model of AF with cardiac specific overexpression of TGF-β1 and investigated the changes in the cardiac structure and function leading to AF. METHODS AND RESULTS: Transgenic goats with cardiac specific overexpression of constitutively active TGF-β1 were generated by somatic cell nuclear transfer...
October 2016: Journal of Cardiovascular Electrophysiology
Junaid A B Zaman, Leanne Harling, Hutan Ashrafian, Ara Darzi, Nigel Gooderham, Thanos Athanasiou, Nicholas S Peters
BACKGROUND: Post-operative atrial fibrillation (POAF) is a major health economic burden. However, the precise mechanisms in POAF remain unclear. In other forms of AF, sites of high dominant frequency (DF) in sinus rhythm (SR) may harbour 'AF nests'. We studied AF inducibility in relation to substrate changes using epicardial electrograms and cardiomyocyte calcium handling in the atria of AF naïve patients. METHOD: Bipolar electrograms were recorded from the lateral right atrial (RA) wall in 34 patients undergoing coronary surgery using a high-density array in sinus rhythm (NSR)...
October 1, 2016: International Journal of Cardiology
Dionyssios Leftheriotis, Panayota Flevari, Charalampos Kossyvakis, Dimitrios Katsaras, Chrysanthi Batistaki, Chrysa Arvaniti, Georgios Giannopoulos, Spyridon Deftereos, Georgia Kostopanagiotou, Ioannis Lekakis
BACKGROUND: In experimental models, stellate ganglion block (SGB) reduces the induction of atrial fibrillation (AF), while data in humans are limited. OBJECTIVE: The aim of this study was to assess the effect of unilateral SGB on atrial electrophysiological properties and AF induction in patients with paroxysmal AF. METHODS: Thirty-six patients with paroxysmal AF were randomized in a 2:1 order to temporary, transcutaneous, pharmaceutical SGB with lidocaine or placebo before pulmonary vein isolation...
June 21, 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Bor Antolič, Andrej Pernat, Marta Cvijić, David Žižek, Matevž Jan, Matjaž Šinkovec
BACKGROUND: Evidence from animal and human studies suggests that cryoablation might be associated with a lesser inflammatory response and activation of coagulation compared with radiofrequency ablation. The study was aimed at comparing the effect of cryoballoon and radiofrequency catheter ablation of paroxysmal atrial fibrillation on markers of myocardial damage, inflammation, and activation of coagulation. METHODS: Forty-one patients received either cryoballoon (n = 23) or radiofrequency (n = 18) ablation of atrial fibrillation...
July 2016: Wiener Klinische Wochenschrift
Jayaprakash Shenthar, Saligrama Ramegowda Kalpana, Mukund A Prabhu, Maneesh K Rai, Ravikumar Kalyani Nagashetty, Giridhar Kamlapurkar
BACKGROUND: Mitral stenosis (MS) has the highest incidence of atrial fibrillation (AF) in chronic rheumatic valvular disease. There are very few studies in isolated MS comparing histopathological changes in patients with sinus rhythm (SR) and AF. OBJECTIVES: To analyze the histological changes associated with isolated MS and compare between changes in AF and SR. METHODS: This was a prospective study in patients undergoing valve replacement surgery for symptomatic isolated MS who were divided into 2 groups, Group I AF (n = 13) and Group II SR (n = 10)...
September 2016: Journal of Cardiovascular Electrophysiology
Vivienne A Ezzat, Matthew J Ryan, Justin O'Leary, Cono Ariti, John Deanfield, Bejal Pandya, Shay Cullen, Fiona Walker, Fakhar Khan, Dominic J Abrams, Pier D Lambiase, Martin D Lowe
BACKGROUND: Adults with tetralogy of Fallot experience atrial tachyarrhythmias; however, there are a few data on the outcomes of radiofrequency ablation. We examined the characteristics, outcome, and predictors of recurrence of atrial tachyarrhythmias after radiofrequency ablation in tetralogy of Fallot patients. Methods/results Retrospective data were collected from 2004 to 2013. In total, 56 ablations were performed on 37 patients. We identified two matched controls per case: patients with tetralogy of Fallot but no radiofrequency ablation and not known to have atrial tachyarrhythmias...
May 26, 2016: Cardiology in the Young
J Jaspers Focks, S P G van Vugt, M T H Albers-Akkers, E J P Lamfers, L M Bloem-de Vries, F W A Verheugt, M A Brouwer
UNLABELLED: Essentials Under-treatment of oral anticoagulation in the elderly with atrial fibrillation is common. As bleeding prediction is challenging, we compared HAS-BLED, ATRIA and HEMORR2 HAGES. All three were associated with major bleeding in the elderly, but with poor predictive abilities. Future studies with focus on elderly-specific risk factors for bleeding are warranted. SUMMARY: Background Anticipated bleeding complications contribute to underuse of oral anticoagulants, especially in elderly patients with atrial fibrillation (AF)...
September 2016: Journal of Thrombosis and Haemostasis: JTH
Feifei Chen, Yanzong Yang, Rongfeng Zhang, Shulong Zhang, Yingxue Dong, Xiaomeng Yin, Dong Chang, Zhiqiang Yang, Kejing Wang, Lianjun Gao, Yunlong Xia
To test polymorphisms rs2200733 (chromosome 4q25) and rs2106261 (ZFHX3) were associated with AF recurrence after catheter ablation in a Chinese Han cohort. A total of 235 AF patients who underwent catheter ablation were recruited consecutively. Two polymorphisms were amplified by polymerase chain reaction and genotyped using high resolution melting analysis. Primary endpoints for AF recurrence were defined as the time to the first recurrence of atrial tachycardia/flutter/fibrillation (AT/AF). AT/AF recurrence was observed in 76 patients (35%)...
2016: American Journal of Translational Research
Jason D Bayer, Caroline H Roney, Ali Pashaei, Pierre Jaïs, Edward J Vigmond
Pulmonary vein isolation (PVI) with radiofrequency ablation (RFA) is the cornerstone of atrial fibrillation (AF) therapy, but few strategies exist for when it fails. To guide RFA, phase singularity (PS) mapping locates reentrant electrical waves (rotors) that perpetuate AF. The goal of this study was to test existing and develop new RFA strategies for terminating rotors identified with PS mapping. It is unsafe to test experimental RFA strategies in patients, so they were evaluated in silico using a bilayer computer model of the human atria with persistent AF (pAF) electrical (ionic) and structural (fibrosis) remodeling...
2016: Frontiers in Physiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"