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JACC. Clinical Electrophysiology Mar 2021
Topics: Atrial Fibrillation; Catheter Ablation; Cicatrix; Embolic Stroke; Heart Atria; Humans
PubMed: 33736752
DOI: 10.1016/j.jacep.2020.12.002 -
The Journal of Thoracic and... Feb 2022Surgical ablation of atrial fibrillation (AF) is indicated both in patients with AF undergoing concomitant cardiac surgery and in those who have not responded to medical...
OBJECTIVE
Surgical ablation of atrial fibrillation (AF) is indicated both in patients with AF undergoing concomitant cardiac surgery and in those who have not responded to medical and/or catheter-based ablation therapy. This study examined our long-term outcomes following the Cox-Maze IV procedure (CMP-IV).
METHODS
Between May 2003 and March 2018, 853 patients underwent either biatrial CMP-IV (n = 765) or a left-sided CMP-IV (n = 88) lesion set with complete isolation of the posterior left atrium. Freedom from atrial tachyarrhythmia (ATA) was assessed for up to 10 years. Rhythm outcomes were compared in multiple subgroups. Predictors of recurrence were determined using Fine-Gray regression, allowing for death as the competing risk.
RESULTS
The majority of patients (513/853, 60%) had nonparoxysmal AF. Twenty-four percent of patients (201/853) had not responded to at least 1 catheter-based ablation. Prolonged monitoring was used in 76% (647/853) of patients during their follow-up. Freedom from ATA was 92% (552/598), 84% (213/253), and 77% (67/87) at 1, 5, and 10 years, respectively. By competing risk analysis, incidence of first ATA recurrence was 11%, 23%, and 35% at 1, 5, and 10 years, respectively. On Fine-Gray regression, age, peripheral vascular disease, nonparoxysmal AF, left atrial size, early postoperative ATAs, and absence of sinus rhythm at discharge were the predictors of first ATA recurrence over 10 years of follow-up.
CONCLUSIONS
The CMP-IV had an excellent long-term efficacy at maintaining sinus rhythm. At late follow-up, the results of the CMP-IV remained superior to those reported for catheter ablation and other forms of surgical ablation for AF. Age, left atrial size, and nonparoxysmal AF were the most relevant predictors of late recurrence.
Topics: Action Potentials; Aged; Atrial Fibrillation; Atrial Function, Left; Databases, Factual; Female; Heart Atria; Heart Rate; Humans; Male; Maze Procedure; Middle Aged; Recurrence; Retrospective Studies; Risk Assessment; Risk Factors; Time Factors; Treatment Outcome
PubMed: 32563577
DOI: 10.1016/j.jtcvs.2020.04.100 -
European Heart Journal. Cardiovascular... Dec 2021Atrial arrhythmias, including atrial fibrillation and atrial flutter, may be treated through catheter ablation. The process of atrial arrhythmia catheter ablation, which... (Review)
Review
Atrial arrhythmias, including atrial fibrillation and atrial flutter, may be treated through catheter ablation. The process of atrial arrhythmia catheter ablation, which includes patient selection, pre-procedural planning, intra-procedural guidance, and post-procedural assessment, is typically characterized by the use of several imaging modalities to sequentially inform key clinical decisions. Increasingly, advanced imaging modalities are processed via specialized image analysis techniques and combined with intra-procedural electrical measurements to inform treatment approaches. Here, we review the use of multimodality imaging for left atrial ablation procedures. The article first outlines how imaging modalities are routinely used in the peri-ablation period. We then describe how advanced imaging techniques may inform patient selection for ablation and ablation targets themselves. Ongoing research directions for improving catheter ablation outcomes by using imaging combined with advanced analyses for personalization of ablation targets are discussed, together with approaches for their integration in the standard clinical environment. Finally, we describe future research areas with the potential to improve catheter ablation outcomes.
Topics: Atrial Fibrillation; Atrial Flutter; Catheter Ablation; Heart Atria; Humans; Multimodal Imaging; Treatment Outcome
PubMed: 34747450
DOI: 10.1093/ehjci/jeab205 -
International Journal of Cardiology Jul 2019Atrial fibrillation is the most common arrhythmia in humans and is associated with high morbidity, mortality and health-related expenses. Computational approaches have... (Review)
Review
Atrial fibrillation is the most common arrhythmia in humans and is associated with high morbidity, mortality and health-related expenses. Computational approaches have been increasingly utilized in atrial electrophysiology. In this review we summarize the recent advancements in atrial fibrillation modeling at the organ scale. Multi-scale atrial models now incorporate high level detail of atrial anatomy, tissue ultrastructure and fibrosis distribution. We provide the state-of-the art methodologies in developing personalized atrial fibrillation models with realistic geometry and tissue properties. We then focus on the use of multi-scale atrial models to gain mechanistic insights in AF. Simulations using atrial models have provided important insight in the mechanisms underlying AF, showing the importance of the atrial fibrotic substrate and altered atrial electrophysiology in initiation and maintenance of AF. Last, we summarize the translational evidence that supports incorporation of computational modeling in clinical practice for development of personalized treatment strategies for patients with AF. In early-stages clinical studies, AF models successfully identify patients where pulmonary vein isolation alone is not adequate for treatment of AF and suggest novel targets for ablation. We conclude with a summary of the future developments envisioned for the field of atrial computational electrophysiology.
Topics: Atrial Fibrillation; Catheter Ablation; Computer Simulation; Heart Atria; Humans; Imaging, Three-Dimensional; Magnetic Resonance Imaging, Cine; Models, Cardiovascular; Tomography, X-Ray Computed
PubMed: 30755334
DOI: 10.1016/j.ijcard.2019.01.096 -
JACC. Clinical Electrophysiology Apr 2019This study sought to characterize primary left atrial tachycardia (LAT) mechanisms, electrical properties and substrate using high-density mapping. (Observational Study)
Observational Study
OBJECTIVES
This study sought to characterize primary left atrial tachycardia (LAT) mechanisms, electrical properties and substrate using high-density mapping.
BACKGROUND
Nonfocal LAT can be found in patients without prior substrate modifying interventions.
METHODS
Of 223 catheter ablation procedures for LAT 15 patients (60% male, age 74 ± 6 years) had nonfocal AT and no history of LA ablation or cardiac surgery.
RESULTS
AT (mean cycle length 244 ± 32 ms) were identified as macro-re-entry (12 of 15) or localized re-entry (3 of 15). High-density electroanatomical mapping (EAM, performed in 13 patients) revealed a high proportion of low voltage areas (LVA, <0.45 mV, 41 ± 22%). Anterior LVA regions were predominantly related to the macro-re-entry and directly perpetuating the re-entrant circuit in 8 patients by formation of a conductive channel (width: 14 ± 7 mm, length: 11 ± 3 mm) between the inferior pole of the scar and the mitral valve (MV) annulus with electrophysiological features of diseased tissue. A tailored anterior ablation line successfully terminated AT in 9 patients (6 dominant circuit MV dependent, 3 dominant circuit scar dependent AT), while a lateral isthmus line was performed in 2 patients. Localized re-entries were successfully targeted by local ablation. Acute successful ablation could be achieved in 14 of 15 patients leading to a freedom from any arrhythmias in 9 of 15 patients (60%) after follow-up of 343 ± 203 days.
CONCLUSIONS
Patients with nonfocal left atrial tachycardia without previous iatrogenic interventions show evidence for advanced atrial myopathy. High-density mapping revealed involvement of the anterior LA and allows for an individualized ablation approach beyond strategies usually applied in consecutive AT.
Topics: Aged; Aged, 80 and over; Catheter Ablation; Electrophysiologic Techniques, Cardiac; Female; Heart Atria; Humans; Male; Prospective Studies; Tachycardia
PubMed: 31000095
DOI: 10.1016/j.jacep.2019.02.002 -
Cardiology Journal 2020Catheter ablation (CA) is a well-known treatment option for patients with symptomatic drug-resistant atrial fibrillation (AF). Multiple factors have been identified to... (Review)
Review
BACKGROUND
Catheter ablation (CA) is a well-known treatment option for patients with symptomatic drug-resistant atrial fibrillation (AF). Multiple factors have been identified to determine AF recurrence after CA, however their predictive value is rather small. Identification of novel predictors of CA outcome is therefore of primary importance to reduce health costs and improve long-term results of intervention. The recurrence of AF following CA is related to severity of left ventricular (LV) dysfunction, extent of atrial dilatation and fibrosis. The aim of this paper was to present and discuss the latest studies on the utility of echocardiographic parameters in terms of CA effectiveness in patients with paroxysmal and persistent AF.
METHODS
PubMed, Google Scholar, EBSCO databases were searched for studies reporting echocardiographic preprocedural predictors of AF recurrence after CA. LV systolic and diastolic function, as well as atrial size, strain and dyssynchrony were taken into consideration.
RESULTS
Twenty one full-text articles were analyzed, including three meta-analyses. Several echocardiographic parameters have been reported to determine a risk of AF recurrence after CA. There are conventional methods that measure left atrial size and volume, LV ejection fraction, parameters assessing LV diastolic dysfunction, and methods using more innovative technologies based on speckle tracking echocardiography to determine left atrial synchrony and strain. Each of these parameters has its own predictive value.
CONCLUSIONS
Regarding CA effectiveness, every patient has to be evaluated individually to estimate the risk of AF recurrence, optimally using a combination of several echocardiographic parameters.
Topics: Atrial Fibrillation; Catheter Ablation; Echocardiography; Heart Atria; Humans; Predictive Value of Tests; Recurrence; Treatment Outcome
PubMed: 29924375
DOI: 10.5603/CJ.a2018.0067 -
Journal of the American College of... Jul 2020Atrial flutter (AFL) and atrial fibrillation (AF) are associated with AF-promoting atrial remodeling, but no experimental studies have addressed remodeling with...
BACKGROUND
Atrial flutter (AFL) and atrial fibrillation (AF) are associated with AF-promoting atrial remodeling, but no experimental studies have addressed remodeling with sustained AFL.
OBJECTIVES
This study aimed to define the atrial remodeling caused by sustained atrial flutter (AFL) and/or atrial fibrillation (AF).
METHODS
Intercaval radiofrequency lesions created a substrate for sustained isthmus-dependent AFL, confirmed by endocavity mapping. Four groups (6 dogs per group) were followed for 3 weeks: sustained AFL; sustained AF (600 beats/min atrial tachypacing); AF superimposed on an AFL substrate (AF+AFLs); sinus rhythm (SR) with an AFL substrate (SR+AFLs; control group). All dogs had atrioventricular-node ablation and ventricular pacemakers at 80 beats/min to control ventricular rate.
RESULTS
Monitoring confirmed spontaneous AFL maintenance >99% of the time in dogs with AFL. At terminal open-chest study, left-atrial (LA) effective refractory period was reduced similarly with AFL, AF+AFLs and AF, while AF vulnerability to extrastimuli increased in parallel. Induced AF duration increased significantly in AF+AFLs and AF, but not AFL. Dogs with AF+AFLs had shorter cycle lengths and substantial irregularity versus dogs with AFL. LA volume increased in AF+AFLs and AF, but not dogs with AFL, versus SR+AFLs. Optical mapping showed significant conduction slowing in AF+AFLs and AF but not AFL, paralleling atrial fibrosis and collagen-gene upregulation. Left-ventricular function did not change in any group. Transcriptomic analysis revealed substantial dysregulation of inflammatory and extracellular matrix-signaling pathways with AF and AF+ALs but not AFL.
CONCLUSIONS
Sustained AFL causes atrial repolarization changes like those in AF but, unlike AF or AF+AFLs, does not induce structural remodeling. These results provide novel insights into AFL-induced remodeling and suggest that early intervention may be important to prevent irreversible fibrosis when AF intervenes in a patient with AFL.
Topics: Animals; Atrial Fibrillation; Atrial Flutter; Atrial Remodeling; Catheter Ablation; Dogs; Electrocardiography; Fibrosis; Heart Atria
PubMed: 32703507
DOI: 10.1016/j.jacc.2020.05.062 -
Europace : European Pacing,... Nov 2021Pulsed field ablation (PFA), a non-thermal ablative modality, may show different effects on the myocardial tissue compared to thermal ablation. Thus, this study aimed to...
AIMS
Pulsed field ablation (PFA), a non-thermal ablative modality, may show different effects on the myocardial tissue compared to thermal ablation. Thus, this study aimed to compare the left atrial (LA) structural and mechanical characteristics after PFA vs. thermal ablation.
METHODS AND RESULTS
Cardiac magnetic resonance was performed pre-ablation, acutely (<3 h), and 3 months post-ablation in 41 patients with paroxysmal atrial fibrillation (AF) undergoing pulmonary vein (PV) isolation with PFA (n = 18) or thermal ablation (n = 23, 16 radiofrequency ablations, 7 cryoablations). Late gadolinium enhancement (LGE), T2-weighted, and cine images were analysed. In the acute stage, LGE volume was 60% larger after PFA vs. thermal ablation (P < 0.001), and oedema on T2 imaging was 20% smaller (P = 0.002). Tissue changes were more homogeneous after PFA than after thermal ablation, with no sign of microvascular damage or intramural haemorrhage. In the chronic stage, the majority of acute LGE had disappeared after PFA, whereas most LGE persisted after thermal ablation. The maximum strain on PV antra, the LA expansion index, and LA active emptying fraction declined acutely after both PFA and thermal ablation but recovered at the chronic stage only with PFA.
CONCLUSION
Pulsed field ablation induces large acute LGE without microvascular damage or intramural haemorrhage. Most LGE lesions disappear in the chronic stage, suggesting a specific reparative process involving less chronic fibrosis. This process may contribute to a preserved tissue compliance and LA reservoir and booster pump functions.
Topics: Atrial Fibrillation; Catheter Ablation; Contrast Media; Fibrosis; Gadolinium; Heart Atria; Humans; Magnetic Resonance Imaging
PubMed: 34240134
DOI: 10.1093/europace/euab155 -
Multimedia Manual of Cardiothoracic... Nov 2020Atrial fibrillation is becoming a disease that needs to be addressed with definitive long-term treatment as opposed to medical management options. Ablation or isolation...
Atrial fibrillation is becoming a disease that needs to be addressed with definitive long-term treatment as opposed to medical management options. Ablation or isolation of focal triggers around the pulmonary veins can eliminate arrhythmia substrates for patients with paroxysmal, lone atrial fibrillation. However, limited pulmonary vein isolation strategies do not address reentrant circuits common in persistent and longstanding persistent patients with structural heart disease and enlarged atria. The convergent procedure is a hybrid ablation treatment for atrial fibrillation. It consists of surgical ablation of the posterior left atrium through a minimally invasive closed-chest approach followed by endocardial catheter ablation. The convergent procedure was developed to treat atrial fibrillation by creating a complete and comprehensive pattern of linear lesions on the left atrial backwall under direct endoscopic visualization while avoiding chest incisions and deflation of the lungs. Endocardial ablation follows the epicardial procedure to confirm lesion integrity and supplement the epicardial procedure, which is performed in a staged fashion.
Topics: Atrial Appendage; Atrial Fibrillation; Catheter Ablation; Endocardium; Endoscopy; Heart Atria; Humans; Male; Middle Aged; Organ Size; Pulmonary Veins; Surgery, Computer-Assisted; Treatment Outcome; Xiphoid Bone
PubMed: 33263364
DOI: 10.1510/mmcts.2020.066 -
JACC. Clinical Electrophysiology Apr 2019The goal of this study was to characterize, in detail, focal atrial tachycardia (AT) arising from the crista terminalis to investigate associations with other atrial...
OBJECTIVES
The goal of this study was to characterize, in detail, focal atrial tachycardia (AT) arising from the crista terminalis to investigate associations with other atrial arrhythmia and to define long-term ablation outcomes.
BACKGROUND
The crista terminalis is known to be the most common site of origin for focal AT, but it is not well characterized.
METHODS
This study retrospectively identified a total of 548 ablation procedures for AT performed at a single center over a 16-year period, of which 171 were arising from the crista terminalis.
RESULTS
Compared with patients with other AT sites of origin, crista terminalis AT patients were older (57.3 vs. 47.3 years), more commonly female (72.9% vs. 59.1%), were more commonly associated with coexistent atrioventricular nodal re-entry tachycardia (17.1% vs. 9.7%), and were more likely to be inducible with programmed stimulation (81.5% vs. 58.9%). There was preferential conduction in the superior-inferior axis along the crista terminalis. Acute ablation success rate was high (92.2%) and improved significantly when three-dimensional mapping was used (98.5%). Recurrence in the first 12 months after a successful ablation was 9.7%. Only 2 patients developed atrial fibrillation over the long-term follow-up of >7 years.
CONCLUSIONS
This large series characterized the clinical and electrophysiological features and immediate and long-term ablation outcomes for AT originating from the crista terminalis. Features of the tachycardia suggest that age-related localized remodeling of the crista terminalis causes a superficial endocardial zone of conduction slowing leading to re-entry. Ablation outcomes were good, with long-term freedom from atrial arrhythmia.
Topics: Atrial Fibrillation; Catheter Ablation; Electrocardiography; Female; Heart Atria; Humans; Male; Middle Aged; Postoperative Complications; Retrospective Studies; Tachycardia; Treatment Outcome
PubMed: 31000098
DOI: 10.1016/j.jacep.2019.01.014