scholarly journals Little variation in the morphology of the atria across 13 orders of birds

2018 ◽  
Author(s):  
Jelle G. H. Kroneman ◽  
Jaeike W. Faber ◽  
Claudia F. Wolschrijn ◽  
Vincent M. Christoffels ◽  
Bjarke Jensen
Keyword(s):  
Literature Review ◽  
Left Atrial ◽  
High Performance ◽  
Pulmonary Veins ◽  
Cardiac Performance ◽  
Cardiac Structure ◽  
Passerine Birds ◽  
Multiple Features ◽  
Atrioventricular Junction ◽  
Left And Right

AbstractMammals and birds acquired high performance hearts and endothermy during their independent evolution from amniotes with many reptile characters. A literature review shows that the variation in atrial morphology is greater in mammals than in ectothermic reptiles. We therefore hypothesized that the transition from ectothermy to endothermy associated with greater variation in cardiac structure. We tested the hypothesis in birds, by assessing the variation in 15 characters in hearts from 13 orders of birds. Hearts were assessed by gross morphology and histology, and we focused on the atria as they have multiple features that lend themselves to quantification. We found bird hearts to have multiple features in common with ectothermic reptiles (synapomorphies), for instance the presence of three sinus horns. Convergent features were shared with crocodylians and mammals, such as the cranial offset of the left atrioventricular junction. Other convergent features like the compact organization of the atrial walls were shared with mammals only. Sinus myocardium expressing Isl1 was node-like (Mallard), thickened (chicken), or anatomically indistinct from surrounding myocardium (Lesser redpoll). Some features were distinctively avian (apomorphies), including the presence of a left atrial antechamber, and the ventral merger of the left and right atrium, which was found in parrots and passerine birds. Most features, however, exhibited little variation. For instance, there were always three systemic veins and two pulmonary veins, whereas among mammals there are 2-3 and 1-7, respectively. Our findings suggest that the transition to high cardiac performance does not necessarily lead to greater variation in cardiac structure.

Transoesophageal: Chambers and vessels

2020 ◽  
pp. 493-542
Keyword(s):  
Left Atrial ◽  
Thoracic Aortic Aneurysm ◽  
Pulmonary Veins ◽  
Transoesophageal Echocardiography ◽  
Pleural Space ◽  
Intramural Haematoma ◽  
Left And Right ◽  
Aortic Transection ◽  
And Function ◽  
Right Atria

This chapter covers the chambers and vessels in transoesophageal echocardiography. It includes the left and right ventricles (size, mass, and function); the left and right atria, including the left atrial appendage; the pulmonary veins; the coronary sinus; the interatrial and interventricular septa; the pericardium and pericardial effusion; cardiac tamponade; the aorta (size, atherosclerosis, and dissection); intramural haematoma; aortic transection; thoracic aortic aneurysm; masses; pleural space and lungs; and implanted devices.

Prenatal ultrasound diagnosis of pulmonary atresia in combination with left atrial isomerism

2017 ◽  
Author(s):  
M Medvedev, M.V. Kubrina, O.S. Zarubina et all
Keyword(s):  
Left Atrial ◽  
Reverse Flow ◽  
Ductus Arteriosus ◽  
Pulmonary Atresia ◽  
Prenatal Ultrasound ◽  
Ultrasound Diagnosis ◽  
Right Atrial ◽  
Second Trimester ◽  
Left And Right ◽  
Atrial Isomerism

Two cases of prenatal ultrasound diagnosis of left atrial isomerism in the second trimester of gestation is presented. These two cases were in combination with pulmonary atresia and right aortic arch. Left atrial isomerism was identify by the digit-like shape of the left and right atrial appendages. The pulmonary atresia was identified on the basis of reverse flow in small pulmonary artery. A right aortic was identified by “U”-shaped confluence of aorta and ductus arteriosus in view of three vessels and trachea. The trachea was located between the vessels. The pregnancies were terminated and prenatal diagnosis was conformed at autopsy

scholarly journals Relationship between left atrial strain and left atrial bipolar voltage in patients undergoing catheter ablation for atrial fibrillation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
Y Takahashi ◽  
T Kitai ◽  
T Watanabe ◽  
T Fujita
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrial ◽  
Speckle Tracking ◽  
Longitudinal Strain ◽  
Low Voltage ◽  
Pulmonary Veins ◽  
Global Longitudinal Strain ◽  
Inferior Wall ◽  
Bipolar Voltage ◽  
Global Mean

Abstract Background Low-voltage zone (LVZ) in the left atrium (LA) seems to represent fibrosis. LA longitudinal strain assessed by speckle tracking method is known to correlate with the extent of fibrosis in patients with mitral valve disease. Purpose We sought to identify the relationship between LA longitudinal strain and LA bipolar voltage in patients with atrial fibrillation (AF). We tested the hypothesis that LA strain can predict LA bipolar voltage. Methods A total of 96 consecutive patients undergoing initial AF ablation were analyzed. All patients underwent transthoracic echocardiography including 2D speckle tracking measurement on the day before ablation during sinus rhythm (SR group, N=54) or during AF (AF group, N=42). LA longitudinal strain was measured at basal, mid, and roof level of septal, lateral, anterior, and inferior wall in apical 4- and 2-chamber view. Global longitudinal strain (GLS) was defined as an average value of the 12 segments. LA voltage map was created using EnSite system, and global mean voltage was defined as a mean of bipolar voltage of the whole LA excluding pulmonary veins and left atrial appendage. LVZ was defined as less than 1.0 mV. Results There was a significantly positive correlation between GLS and global mean voltage (r=0.708, p<0.001). Multivariate regression analysis showed that GLS and age were independent predictors of global mean voltage. There was a significant negative correlation between global mean voltage and LVZ areas. Conclusions There was a strong correlation between LA longitudinal strain and LA mean voltage. GLS can independently predict LA mean voltage, subsequently LVZ areas in patients with AF. Funding Acknowledgement Type of funding source: None

scholarly journals Fluid–structure interaction in a fully coupled three-dimensional mitral–atrium–pulmonary model

2021 ◽  
Author(s):  
Liuyang Feng ◽  
Hao Gao ◽  
Nan Qi ◽  
Mark Danton ◽  
Nicholas A. Hill ◽  
...  
Keyword(s):  
Mitral Valve ◽  
Left Atrium ◽  
Left Atrial ◽  
Left Atrial Appendage ◽  
Pulmonary Veins ◽  
Three Dimensional ◽  
Left Heart ◽  
Structure Interaction ◽  
Acute Mitral Regurgitation ◽  
Reversal Flow

AbstractThis paper aims to investigate detailed mechanical interactions between the pulmonary haemodynamics and left heart function in pathophysiological situations (e.g. atrial fibrillation and acute mitral regurgitation). This is achieved by developing a complex computational framework for a coupled pulmonary circulation, left atrium and mitral valve model. The left atrium and mitral valve are modelled with physiologically realistic three-dimensional geometries, fibre-reinforced hyperelastic materials and fluid–structure interaction, and the pulmonary vessels are modelled as one-dimensional network ended with structured trees, with specified vessel geometries and wall material properties. This new coupled model reveals some interesting results which could be of diagnostic values. For example, the wave propagation through the pulmonary vasculature can lead to different arrival times for the second systolic flow wave (S2 wave) among the pulmonary veins, forming vortex rings inside the left atrium. In the case of acute mitral regurgitation, the left atrium experiences an increased energy dissipation and pressure elevation. The pulmonary veins can experience increased wave intensities, reversal flow during systole and increased early-diastolic flow wave (D wave), which in turn causes an additional flow wave across the mitral valve (L wave), as well as a reversal flow at the left atrial appendage orifice. In the case of atrial fibrillation, we show that the loss of active contraction is associated with a slower flow inside the left atrial appendage and disappearances of the late-diastole atrial reversal wave (AR wave) and the first systolic wave (S1 wave) in pulmonary veins. The haemodynamic changes along the pulmonary vessel trees on different scales from microscopic vessels to the main pulmonary artery can all be captured in this model. The work promises a potential in quantifying disease progression and medical treatments of various pulmonary diseases such as the pulmonary hypertension due to a left heart dysfunction.

scholarly journals Persistent Atrial Fibrillation: The Role of Left Atrial Posterior Wall Isolation and Ablation Strategies

2021 ◽  
Vol 10 (14) ◽  
pp. 3129
Author(s):  
Riyaz A. Kaba ◽  
Aziz Momin ◽  
John Camm
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrial ◽  
Pulmonary Veins ◽  
Treatment Strategies ◽  
Persistent Atrial Fibrillation ◽  
Posterior Wall ◽  
Cardiovascular Death ◽  
Good Effect ◽  
Complex Forms

Atrial fibrillation (AF) is a global disease with rapidly rising incidence and prevalence. It is associated with a higher risk of stroke, dementia, cognitive decline, sudden and cardiovascular death, heart failure and impairment in quality of life. The disease is a major burden on the healthcare system. Paroxysmal AF is typically managed with medications or endocardial catheter ablation to good effect. However, a large proportion of patients with AF have persistent or long-standing persistent AF, which are more complex forms of the condition and thus more difficult to treat. This is in part due to the progressive electro-anatomical changes that occur with AF persistence and the spread of arrhythmogenic triggers and substrates outside of the pulmonary veins. The posterior wall of the left atrium is a common site for these changes and has become a target of ablation strategies to treat these more resistant forms of AF. In this review, we discuss the role of the posterior left atrial wall in persistent and long-standing persistent AF, the limitations of current endocardial-focused treatment strategies, and future perspectives on hybrid epicardial–endocardial approaches to posterior wall isolation or ablation.

scholarly journals Supervised Domain Adaptation for Automated Semantic Segmentation of the Atrial Cavity

Entropy ◽  
2021 ◽  
Vol 23 (7) ◽  
pp. 898
Author(s):  
Marta Saiz-Vivó ◽  
Adrián Colomer ◽  
Carles Fonfría ◽  
Luis Martí-Bonmatí ◽  
Valery Naranjo
Keyword(s):  
High Performance ◽  
Computational Models ◽  
Domain Adaptation ◽  
Semantic Segmentation ◽  
Patient Specific ◽  
Mr Images ◽  
Training Samples ◽  
Volumetric Images ◽  
Acquisition Costs ◽  
Left And Right

Atrial fibrillation (AF) is the most common cardiac arrhythmia. At present, cardiac ablation is the main treatment procedure for AF. To guide and plan this procedure, it is essential for clinicians to obtain patient-specific 3D geometrical models of the atria. For this, there is an interest in automatic image segmentation algorithms, such as deep learning (DL) methods, as opposed to manual segmentation, an error-prone and time-consuming method. However, to optimize DL algorithms, many annotated examples are required, increasing acquisition costs. The aim of this work is to develop automatic and high-performance computational models for left and right atrium (LA and RA) segmentation from a few labelled MRI volumetric images with a 3D Dual U-Net algorithm. For this, a supervised domain adaptation (SDA) method is introduced to infer knowledge from late gadolinium enhanced (LGE) MRI volumetric training samples (80 LA annotated samples) to a network trained with balanced steady-state free precession (bSSFP) MR images of limited number of annotations (19 RA and LA annotated samples). The resulting knowledge-transferred model SDA outperformed the same network trained from scratch in both RA (Dice equals 0.9160) and LA (Dice equals 0.8813) segmentation tasks.

scholarly journals Left Circumflex Artery Rupture with Left Atrial Tamponade and Functional Mitral Stenosis

2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
Weiting Huang ◽  
Khaled Mohamed Emadeldin Moheb Hammad ◽  
Victor Tar Toong Chao ◽  
Khung Keong Yeo
Keyword(s):  
Left Atrium ◽  
Coronary Sinus ◽  
Mitral Stenosis ◽  
Left Atrial ◽  
Pulmonary Veins ◽  
Fluid Collection ◽  
Artery Dissection ◽  
Circumflex Artery ◽  
Left Circumflex Artery ◽  
Coronary Syndrome

The growth in percutaneous transluminal devices has enabled operators to tackle more complex, native, and post-bypass surgery anatomy. However, complications such as coronary artery dissection, coronary perforation, retrograde aortic dissection, arrhythmias, and acute coronary syndrome still occur with resulting mortality rates of up to 4.2% in complex interventions. Perforation of the circumflex artery is of particular interest in view of its position and relation to the surrounding cardiac structures. This is a site of potential fluid collection, and as the left atrium is fixed to the parietal pericardium at the entry of the pulmonary veins, fluid in the oblique sinus can accumulate enough pressure to compress the left atrium and the coronary sinus. We present a case of left circumflex artery perforation which demonstrates the physiologic complications of coronary sinus and left atrial compression and the resultant functional mitral stenosis.

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