Atrial Fibrillation: Is Our Electrophysiological Understanding on the Right Wavelength?

Abstract Background Atrial fibrillation (AF) is the most common cardiac arrhythmia treated in clinical practice. Structural remodeling is characterized by atrial enlargement and contributes to the therapeutic resistance in patients with long-standing AF. Purpose To study the atrial arrhythmogenic and echocardiographic consequences induced by volume overload in the complete chronic atrioventricular block (CAVB) dog. Methods Echocardiographic and electrophysiological data was obtained in 14 anaesthetized Mongrel dogs, in acute AV-block (AAVB), after 6 weeks of CAVB (CAVB6) and CAVB10. Left atrial (LA) volume was determined with 2D echocardiography by using the biplane method. An electrocardiogram and monophasic action potentials (MAP) at the right atrial (RA) free wall were recorded. Atrial effective refractory period (AERP) was determined by continuous programmed electrical stimulation (PES) of 20 beats with a cycle length of 400 ms and an extrastimulus with decremental design until refractoriness was reached. A continuous PES protocol of 20 beats with an extrastimulus 5 ms longer than the AERP was applied for 150 seconds to trigger AF. After 5 min without arrhythmias, autonomic neuromodulation was performed by intravenous infusion (IV) of acetylcholine (1,5μg/kg/min to 6,0μg/kg/min) for 20 min followed by prompt IV infusion of isoprenaline (3μg/min) until the atrial heart rate increased by 20 bpm. PES with an extrastimulus was repeated for 150 seconds to induce AF. Results LA volume increased from 13.7±3.2 ml at AAVB to 20.5±5.9 ml* at CAVB6, and 22.7±6.0 ml* at CAVB10 (Fig. 1A). AERP was similar at AAVB, CAVB6, and CAVB10 (115.8±11.9, 117.3±11.7, and 106.8±12.1 ms respectively). Repetitive AF paroxysms of >10 seconds were induced in 1/14 (7%) dogs at AAVB, 1/11 (9%) at CAVB6, and 5/10 (50%)* at CAVB10 (*p<0.05) upon PES (Fig. 1B). Combined neuromodulation and PES did not increase the AF inducibility rate, but prolonged the longest episode of AF in the inducible dogs from 55±49 seconds to 236±202 seconds* at CAVB10 (Fig. 1C). LA volume was higher in inducible dogs 25.0±4.9 ml compared to 18.4±4.2 ml in non-inducible dogs at CAVB10. Conclusion Sustained atrial dilation forms a substrate for repetitive paroxysms of AF. Neuro-modulation prolongs AF episode duration in susceptible dogs. This animal model can be used to study structural remodeling of the atria and possible therapeutic advances in the management of AF. Figure 1 Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Amgen Research

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Right Atrial Thrombosis and Pulmonary Embolism: A Narrative Review

Seminars in Thrombosis and Hemostasis ◽

10.1055/s-0040-1718399 ◽

2020 ◽

Vol 46 (08) ◽

pp. 895-907

Author(s):

Nina D. Anfinogenova ◽

Oksana Y. Vasiltseva ◽

Alexander V. Vrublevsky ◽

Irina N. Vorozhtsova ◽

Sergey V. Popov ◽

...

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Embolism ◽

High Risk ◽

Transesophageal Echocardiography ◽

Three Dimensional ◽

Right Atrial ◽

Treatment Protocols ◽

High Risk Patients ◽

Risk Patients ◽

The Right

AbstractPrompt diagnosis of pulmonary embolism (PE) remains challenging, which often results in a delayed or inappropriate treatment of this life-threatening condition. Mobile thrombus in the right cardiac chambers is a neglected cause of PE. It poses an immediate risk to life and is associated with an unfavorable outcome and high mortality. Thrombus residing in the right atrial appendage (RAA) is an underestimated cause of PE, especially in patients with atrial fibrillation. This article reviews achievements and challenges of detection and management of the right atrial thrombus with emphasis on RAA thrombus. The capabilities of transthoracic and transesophageal echocardiography and advantages of three-dimensional and two-dimensional echocardiography are reviewed. Strengths of cardiac magnetic resonance imaging (CMR), computed tomography, and cardiac ventriculography are summarized. We suggest that a targeted search for RAA thrombus is necessary in high-risk patients with PE and atrial fibrillation using transesophageal echocardiography and/or CMR when available independently on the duration of the disease. High-risk patients may also benefit from transthoracic echocardiography with right parasternal approach. The examination of high-risk patients should involve compression ultrasonography of lower extremity veins along with the above-mentioned technologies. Algorithms for RAA thrombus risk assessment and protocols aimed at identification of patients with RAA thrombosis, who will potentially benefit from treatment, are warranted. The development of treatment protocols specific for the diverse populations of patients with right cardiac thrombosis is important.

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Anatomical correlation between left atrium pulmonary vein ablation targets of atrial fibrillation and adjacent bronchi and pulmonary arteries by MSCT

BMC Cardiovascular Disorders ◽

10.1186/s12872-021-01881-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yan-Jing Wang ◽

Huan Sun ◽

Xiao-Fei Fan ◽

Meng-Chao Zhang ◽

Ping Yang ◽

...

Keyword(s):

Atrial Fibrillation ◽

Left Atrium ◽

Pulmonary Vein ◽

Pulmonary Arteries ◽

Contact Points ◽

Pulmonary Vein Ablation ◽

Adjacent Structures ◽

Anatomical Correlation ◽

The Right

Abstract Background The ablation targets of atrial fibrillation (AF) are adjacent to bronchi and pulmonary arteries (PAs). We used computed tomography (CT) to evaluate the anatomical correlation between left atrium (LA)-pulmonary vein (PV) and adjacent structures. Methods Data were collected from 126 consecutive patients using coronary artery CT angiography. The LA roof was divided into three layers and nine points. The minimal spatial distances from the nine points and four PV orifices to the adjacent bronchi and PAs were measured. The distances from the PV orifices to the nearest contact points of the PVs, bronchi, and PAs were measured. Results The anterior points of the LA roof were farther to the bronchi than the middle or posterior points. The distances from the nine points to the PAs were shorter than those to the bronchi (5.19 ± 3.33 mm vs 8.62 ± 3.07 mm; P < .001). The bilateral superior PV orifices, especially the right superior PV orifices were closer to the PAs than the inferior PV orifices (left superior PV: 7.59 ± 4.14 mm; right superior PV: 4.43 ± 2.51 mm; left inferior PV: 24.74 ± 5.26 mm; right inferior PV: 22.33 ± 4.75 mm) (P < .001). Conclusions The right superior PV orifices were closer to the bronchi and PAs than other PV orifices. The ablation at the mid-posterior LA roof had a higher possibility to damage bronchi. CT is a feasible method to assess the anatomical adjacency in vivo, which might provide guidance for AF ablation.

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Treating the right patient at the right time: An innovative approach to the management of atrial fibrillation

Canadian Journal of Cardiology ◽

10.1016/s0828-282x(08)70583-x ◽

2008 ◽

Vol 24 (3) ◽

pp. 195-198 ◽

Cited By ~ 21

Author(s):

Anne M. Gillis ◽

Laurie Burland ◽

Beverly Arnburg ◽

Cheryl Kmet ◽

P. Timothy Pollak ◽

...

Keyword(s):

Atrial Fibrillation ◽

Innovative Approach ◽

The Right

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Abstract 15570: Direct Evidence of Endo-Epicardial Dissociation of the Atrial Wall in Patients With Longstanding Persistent Atrial Fibrillation

Circulation ◽

10.1161/circ.132.suppl_3.15570 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Natasja de Groot ◽

Lisette vd Does ◽

Ameeta Yaksh ◽

Paul Knops ◽

Pieter Woestijne ◽

...

Keyword(s):

Atrial Fibrillation ◽

Direct Evidence ◽

Persistent Atrial Fibrillation ◽

Right Atrial ◽

Electrode Arrays ◽

Atrial Wall ◽

Ablative Therapies ◽

Epicardial Layer ◽

Right Atrial Appendage ◽

The Right

Introduction: Transition of paroxysmal to longstanding persistent atrial fibrillation (LsPAF) is associated with progressive longitudinal dissociation in conduction and a higher incidence of focal fibrillation waves. The aim of this study was to provide direct evidence that the substrate of LsPAF consists of an electrical double-layer of dissociated waves, and that focal fibrillation waves are caused by endo-epicardial breakthrough. Hypothesis: LsPAF in humans is caused by electrical dissociation of the endo- and epicardial layer. Methods: Intra-operative mapping of the endo- and epicardial right atrial wall was performed in 9 patients with induced (N=4), paroxysmal (N=1), persistent (N=2) or longstanding-persistent AF (N=2). A clamp of two rectangular electrode-arrays (128 electrodes; inter-electrode distance 2mm) was introduced through an incision in the right atrial appendage. Series of 10 seconds of AF were analyzed and the incidence of endo-epicardial dissociation (≥15ms) was determined for all 128 endo-epicardial recording sites. Results: In patients with LsPAF the averaged degree of endo-epicardial dissociation was highest (24.9% vs. 5.9%). Using strict criteria for breakthrough (presence of an opposite wave within 4mm and <15ms before the origin of the focal wave), the far majority (77%) of all focal fibrillation waves could be attributed to endo-epicardial excitation. Conclusions: During LsPAF considerable differences in activation of the right endo- and epicardial wall exist. Endo-epicardial fibrillation waves that are out of phase, may conduct transmurally and create breakthrough waves in the opposite layer. This may explain the high persistence of AF and the low succes rate of ablative therapies in patients with LsPAF.

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Abstract 18601: Impact of Right and Left Atrial Remodeling on Outcomes From Atrial Fibrillation Rotor Ablation

Circulation ◽

10.1161/circ.132.suppl_3.18601 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Amir Schricker ◽

Tina Baykaner ◽

Junaid Zaman ◽

Gautam Lalani ◽

Kenneth Hopper ◽

...

Keyword(s):

Atrial Fibrillation ◽

Left Atrial ◽

Structural Changes ◽

Unknown Etiology ◽

Atrial Remodeling ◽

Left Atrial Remodeling ◽

Single Procedure ◽

Clinical Indices ◽

The Right

Introduction: Targets for the ablation of atrial fibrillation (AF) are debated. In particular, recent studies questioning fractionated electrograms and lines has increased focus on AF substrates of rotors and focal impulses. These AF sources are seen in both atria, but have unknown etiology. We hypothesized that differential remodeling between the right atrium (RA), whose structural changes are largely undefined, and left atrium (LA) influence the distribution of AF sources and the outcomes from AF source ablation. Methods: In 60 patients at AF ablation (62±10 years, 60% persistent, 5% long-standing persistent), we compared size differences between RA and LA to the number of sources in each chamber and outcomes from AF source-guide ablation. We studied if a 64-pole basket differentially fit the LA or RA, judged by deformation of its splines by the atria (fig. A, B) over multiple cardiac cycles on fluoroscopy. Ablation targeted sources in both atria and was followed by PVI, with follow-up per guidelines. Results: Using baskets in both atria, 205 sources (LA 138; RA 67) were identified and ablated. Notably, the same basket in each patient was dynamically deformed by RA in 51 (85%) of cases but in the LA in only 39 (65%), indicating greater LA remodeling. The number of AF sources was higher in the presence of basket deformation of RA (n=174) than LA (n=130). LA deformation correlated with LVEF (p=0.05). Freedom from AF at 1 year was reduced in patients with no basket deformation (i.e. dilation) in LA (p=0.07) or RA (p=0.06). Notably, single procedure AF freedom was substantially lower in patients with differential remodeling (deformation in only 1 chamber) of 84% vs. 60% (fig C). Conclusions: Structural atrial remodeling influences the number of electrical rotors and focal sources in each chamber. A mismatch between right and left atrial remodeling predicts lower success from rotor ablation. These data also provide novel clinical indices of effective basket positioning.

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659Left atrial wall thickness evaluation during atrial fibrillation redo procedures

EP Europace ◽

10.1093/europace/euaa162.239 ◽

2020 ◽

Vol 22 (Supplement_1) ◽

Author(s):

C Teres ◽

D Soto ◽

B Jauregui ◽

D Penela ◽

A Ordonez ◽

...

Keyword(s):

Atrial Fibrillation ◽

Wall Thickness ◽

Atrial Wall ◽

Ablation Procedure ◽

Left Atrial Wall ◽

Local Distance ◽

The Mean ◽

The Right ◽

The Relationship ◽

Funding Acknowledgements

Abstract Funding Acknowledgements Dr Teres was funded by Swiss Heartrhythm Foundation Introduction pulmonary vein (PV) reconnections due to gaps on circumferential ablation lines are responsible for atrial fibrillation recurrences after catheter ablation. We sought to analyze the local left atrial wall thickness (LAWT) of PV line gaps at AF redo ablation during real-time catheter positioning. LAWT was measured on the MDCT 3D reconstruction and fused with the LA anatomy using CARTO-merge. Objective To analyze the relationship between local reconnection gaps and the LAWT during AF redo procedures. Methods Single-Center cohort study that included 41 consecutive patients referred for AF redo procedure. All patients had a MDCT prior to the ablation procedure. LAWT maps were semi-automatically computed from the MDCT as the local distance between the LA endo and epicardium. Each PV line was subdivided into 8 segments and mean LAWT was computed. During the procedure, the local gap was defined as the earliest activation site at the reconnected segment of the circumferential PV line (Figure 1A & 1B). Results 41 patients [31 (75.6%) male, age 60 ± 10 years] were included. Mean LAWT was 1.36 ± 0.20 mm. Mean PV circumferential line WT was higher in left PVs than in the right PVs 1.68 ± 0.57 vs. 1.31 ± 0.39 mm p < 0.001 respectively. Mean WT of the reconnected points was 44% higher than the mean WT of the segment where the reconnection was located. Mean reconnection point WT was at the 87th percentile of the circumferential line in the LPVs and at the 76th percentile in the RPVs. The reconnected point WT was higher in the LPVs than RPVs 2.13 ± 1.14 vs. 1.47 ± 0.48 mm p < 0.001 respectively. The most frequent location for reconnections was the left anterior carina (71%), with a mean WT of 2.24 ± 0.91mm; and the right anterior carina (56%) with a mean WT of 1.57 ± 0.62mm (Figure 2A & 2B). Conclusions Reconnection points were more frequently present in the thicker segments of the PV circumferential line. The most frequently reconnected segment was the anterior carina in both right and left PVs. Atrial wall thickness maps derived from MDCT are useful to guide AF redo procedures. Abstract Figure. 1) Activation & WT map; 2) Segment WT

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Cardiac Arrhythmia Caused by a Kirschner Wire inside the Heart

Journal of Hand Surgery (European Volume) ◽

10.1016/s0266-7681(97)80412-3 ◽

1997 ◽

Vol 22 (3) ◽

pp. 402-404 ◽

Cited By ~ 29

Author(s):

T. A. T. HAAPANIEMI ◽

U. S. HERMANSSON

Keyword(s):

Atrial Fibrillation ◽

Thoracic Surgery ◽

Cardiac Disease ◽

Kirschner Wire ◽

Previous History ◽

Kirschner Wires ◽

Left Hand ◽

Plain Chest ◽

History Of ◽

The Right

A 45-year-old woman with no previous history of cardiac disease woke up one morning with an irregular heartbeat and fatigue. An electrocardiogram showed atrial fibrillation and plain chest radiographs revealed the presence of a metallic pin at the position of the heart. A 24 mm-long metallic pin was removed by open thoracic surgery from within the right ventricle of the heart. Postoperative examination of the pin showed it to be one of the 0.8 mm Kirschner wires that had been used for finger osteosynthesis in her left hand 31 months previously.

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P3527Echocardiographic assessment of the right ventricle in chronic heart failure with focus on patients with atrial fibrillation

European Heart Journal ◽

10.1093/eurheartj/ehz745.0391 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

E Majos ◽

A Kraska ◽

I Kowalik ◽

E Smolis-Bak ◽

H Szwed ◽

...

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Right Ventricle ◽

Right Ventricular ◽

Systolic Function ◽

Pressure Overload ◽

Ventricular Ejection Fraction ◽

Rv Pacing ◽

The Right ◽

Rv Function

Abstract Background Assessment of the right ventricle (RV) in heart failure (HF) is challenging and requires applicable methods and parameters. Atrial fibrillation (AF) is a common and clinically significant arrhythmia in 30–50% of HF patients. Assessment of the RV function in patients with AF is problematic. Still little is known about RV function in HF and AF patients. The aim of the study was to assess RV function in HF with focus on AF patients. Methods Patients with HF of ischemic etiology, NYHA II-III, LVEF ≤40%, with AF and sinus rhythm (SR), underwent two- and three- dimensional echocardiography (2DE and 3DE) for assessment of the RV with use of multiple parameters. The RV was examined for: linear dimensions, end-diastolic and end-systolic areas adjusted to body surface area (RV EDA and RV ESA/BSA) and end-diastolic and end-systolic volumes adjusted to lean body mass (RV EDV and RV ESV/LBM) to reflect volume overload and in terms of right ventricular pressure (RVSP) as an index of pressure overload. RV systolic function was assessed with 2DE: tricuspid annular plane systolic excursion (TAPSE), right ventricular fractional area change (RV FAC), tricuspid lateral annular systolic velocity (s') and 3DE parameters: right ventricular ejection fraction (RVEF) and free wall right ventricular longitudinal strain (FW RVLS). Also, TAPSE/RVSP parameter was included. Results The study included 126 patients: 94 with AF and 32 with SR. Within the AF group 28 patients were treated medically, 41 had RV pacing (pacemaker or an implantable cardioverter-defibrillator, ICD) and 25 had cardiac resynchronisation therapy (CRT). In comparison with SR group AF patients had: larger RV inflow tract dimension (4.49±0.85 vs. 3.95±0.72 cm; p=0.0017), RV EDA/BSA (12.7±3.9 vs. 11.1±3.0 cm2/m2; p=0.0358) and RV ESA/BSA (8.0±3.0 vs. 6.7±2.4 cm2/m2; p=0.0226). Similarly, patients with AF had greater RV volumes in 3DE than patients with SR: RV EDV/LBM (1.82±0.60 vs. 1.61±0.38ml/kg, p=0.0267) and RV ESV/LBM (1.11±0.40 ml/kg vs. 0.81±0.28, p<0,0001). Also, in patients with AF right ventricular systolic pressure (RVSP) was higher (40.8±10.2 vs. 34.0±8.1 mmHg, p=0,0010). No differences in TAPSE and RVFAC were found but the relation TAPSE/RVSP was higher in AF than in SR group (0.51±0.21 vs. 0.65±0.24 cm/mmHg; p=0.0046). Also, in AF patients in comparison to SR group some parameters had worse values: s' (9.7±2.31 vs. 12.1±3.83, p=0.014), RVEF (37.2±7.3 vs. 48.2±7.5, p<0.0001 and FW RVLS (−18.3±4.6 vs. −23.9±4.23%, p<0,0001). Within the AF group no significant differences in studied variables depending on RV pacing or CRT were found. Conclusions Larger volumes and higher pressure overload of the RV were observed in patients with AF in comparison to SR. Systolic function of the RV seems to be more depressed in AF compared to SR patients with systolic heart failure. Further research in larger groups is required to identify the most applicable and valuable methods of RV evaluation.

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Ischemic stroke with agraphestesia signal focus

10.5327/1516-3180.470 ◽

2021 ◽

Author(s):

Ana Luísa Lopes Espínola da Costa Reis ◽

Leonardo Henrique Gandolfi de Souza ◽

Vitor Roberto Pugliesi Marques

Keyword(s):

Atrial Fibrillation ◽

Ischemic Stroke ◽

Parietal Lobe ◽

Cerebral Arteries ◽

Sudden Onset ◽

Neurological Deficits ◽

Motor Deficits ◽

Ischemic Event ◽

The Right ◽

Sensory Ability

Introduction: The ischemic stroke is one of the main causes of death and disability in Brazil. Among the main risk factors are age, atrial fibrillation (AF), diabetes, dyslipidemia and physical inactivity. The main etiology of stroke is cardioembolic, resulting in obstruction of the cerebral arteries by a thrombus of cardiac origin. The artery most affected in ischemic strokes is the middle cerebral artery. The stroke has main characteristics, with emphasis on the sudden onset of symptoms, involvement of a focal area, ischemia caused by obstruction of a vessel and neurological deficits depending on the affected area. Graphesthesia is defined as a cutaneous sensory ability to recognize letters or numbers traced on the skin. The loss of this sensory ability is known as agraphesthesia. Case Report: M.A.F.O. female, 78a, arrived at the UPA complaining of mental confusion. Patient denies previous stroke. Personal history of systemic arterial hypertension. Upon physical examination, the patient was conscious, self and disoriented and inattentive. He was able to repeat and evoke words, without measurable motor déficits. Left upper limb with agraphestesia. Computed tomography was requested, which showed an extensive hypodense area in the right parietoccipital region, which leads to the erasure of the furrows between the adjacent gyres, which may correspond to a recent ischemic event. Magnetic resonance imaging, diffusion-restricted area with correspondence on the ADC map, located in the right temporoparietal region inferring an acute ischemic event. An electrocardiogram was also requested, which showed an irregular rhythm, characteristic of atrial fibrillation, resulting in a diagnostic hypothesis of cardioembolic ischemic stroke. Discussion: The involvement of post-central ischemic gyrus lesions may correspond to paresthesia, anesthesia, hypoesthesia; the involvement of secondary and terciary areas of sensitivity in the upper parietal lobe, especially in the active movements of the hand and in the modalities of integrated sensitivity, their lesions may be clinically affected by: apraxias, dysgraphias, hemineglect, agraphestesia, stereoagnosia and spacial disorientation.

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